JP2000347386A - Method for correcting defect of mask for exposure, mask for exposure, exposure method, semiconductor device and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the influence of lowering of light transmittance caused in the removal of a black defect with a focused ion beam. SOLUTION: In this method for correcting a black defect 21 of a mask for exposure comprising a substrate 10 transparent to light for exposure, having a 1st group 320 of light transmission regions formed on the substrate 10 and a 2nd group 330 of other light transmission regions formed on the substrate 10 and causing a prescribed phase contrast between light for exposure which passed through the 1st group 320 and light for exposure which passed through the 2nd group 330, the black defect 21 remaining in a light transmission region is removed with a focused ion beam and the group of light transmission regions including the light transmission region freed of the black defect are etched to a prescribed depth.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for correcting a defect of an exposure mask, an exposure mask, an exposure method using the exposure mask, a semiconductor device manufactured by applying the exposure method, and a semiconductor device using the same. The present invention relates to a method for manufacturing a semiconductor device to which an exposure method is applied.

[0002]

2. Description of the Related Art A photolithography technique used in the field of microfabrication such as the manufacture of a semiconductor device uses an exposure apparatus and an exposure mask (also referred to as a photomask or a reticle). This is a technique for transferring the above circuit pattern to a photoresist layer on a substrate. In recent years, in the manufacture of semiconductor devices in which miniaturization and high integration have been remarkably advanced, a reduced projection exposure apparatus is used as an exposure apparatus, and exposure is repeated while changing a relative position between a substrate and an exposure light source, so that photolithography is performed. Many identical patterns are transferred to the resist layer. If a defect exists in the exposure mask, the defect is reflected in all the patterns transferred to the photoresist layer and becomes a fixed defect, which significantly impairs the performance and manufacturing yield of the semiconductor device. Defect-free is strongly desired.

Until the generation in which the minimum processing size of a semiconductor device is a half-micron level (around 0.5 μm), a metal light-shielding layer according to a predetermined pattern is formed on a transparent substrate made of quartz or the like as an exposure mask. So-called metal light-shielding layer masks have been widely used. Since a chrome layer is generally used as the metal light-shielding layer, such an exposure mask is sometimes called a chrome mask. The metal light-shielding layer mask is an exposure mask that controls only the transmission and shielding of exposure light.
Therefore, typical defects that can occur in the metal light-shielding layer mask include a white defect in which a part of the light-shielding layer is missing, and a black defect in which an extra light-shielding layer remains in a light transmission region where exposure light should originally pass. is there. The removal of black defects is generally performed by focused ion beam (FIB) irradiation or laser irradiation. In FIB irradiation, a black defect is sputter-etched using an ion beam, and a gallium (Ga) ion beam is widely used as the ion beam. Laser irradiation is a method of irradiating a black defect with a laser beam and instantaneously heating and evaporating the laser beam. A YAG laser is widely used as a laser light source.

On the other hand, in a generation in which the minimum processing size of a semiconductor device is reduced to a submicron level (about 0.3 μm), a phase shift mask has been put into practical use as an exposure mask. A phase shift mask is provided with two or more types of light transmission areas having different optical characteristics on a substrate transparent to exposure light, and applies exposure light transmitted through each light transmission area (hereinafter sometimes referred to as transmitted light). By providing a phase difference, this is an exposure mask that improves the resolution of a pattern by utilizing the mutual interference of transmitted light, and enables the resolution of a pattern having a size smaller than the wavelength of the exposure light to be used. A member that generates a phase difference (hereinafter, sometimes referred to as a shifter)
As silicon oxide (Si
O ₂₎ transparent layer or the like layer, a molybdenum silicide formed to a predetermined thickness (MoSi _x) layer or chromium oxide (Cr
O) layer and the like. When a groove is engraved at a predetermined depth in the substrate, a portion of the substrate corresponding to the depth of the groove serves as a shifter. The predetermined thickness or the predetermined depth is basically a thickness or a depth capable of producing a phase difference of 180 °. When the phase difference of the transmitted light between adjacent light transmitting regions is 180 °, the light intensity becomes zero at the boundary between the light transmitting regions, and the pattern is separated (that is, resolved).

Various mask structures have been proposed for the phase shift mask depending on the type of the shifter and the presence or absence of the light shielding layer. For example, an exposure mask having a light-shielding layer formed according to a line-and-space pattern and a transparent layer that alternately covers a space between adjacent light-shielding layers (lines) is a so-called Levenson. Also known as a mold mask. Levenson-type masks include a type in which such a transparent layer is provided on a substrate including on a light-shielding layer (upper shifter type) and a type in which the transparent layer is provided between the substrate and the light-shielding layer (lower shifter type). Instead of using such a transparent layer, there is also known a so-called substrate engraving type Levenson-type mask in which a substrate is alternately engraved in a space between adjacent light shielding layers to form a groove.
Alternatively, there is also a Levenson-type mask in which a shallow groove portion and a deep groove portion are alternately formed in all spaces between adjacent light-shielding layers. Further, a so-called halftone mask having only a semi-light-shielding layer without a light-shielding layer is also known.

[0006] The types of defects that can occur in the phase shift mask vary depending on the mask structure described above. Upper shifter
In the type Levenson-type mask, there is a possibility that a processing residue of the transparent layer remains on the substrate as a shifter defect. In the lower shifter type Levenson-type mask, the processing residue of the light-shielding layer may remain as a black defect on the transparent layer, and the processing residue of the transparent layer may remain as the shifter defect on the substrate.
In the Levenson-type mask of the substrate engraving type, the processing residue of the light-shielding layer may remain as a black defect on the substrate, and the processing residue of the substrate may remain as a shifter defect in the groove.
Further, in the halftone mask, a processing residue of the semi-light-shielding layer may remain on the substrate as a shifter defect. These defects are also the same as the black defects of the metal light shielding layer mask,
It is removed by B irradiation or laser irradiation.

[0007]

However, the conventional method of removing defects has a problem. First, in the method using laser irradiation, precise removal is difficult at present due to the non-uniformity of the light intensity distribution in the beam spot of the laser light and the lack of positioning accuracy of the irradiation area. this is,
This is due to the configuration of the laser mask repair device. That is,
In a normal apparatus configuration, a laser beam emitted from a laser light source is enlarged by a beam expander, passes through a variable slit, and is shaped (generally, into a rectangle). Although the light is condensed, there is a limit in the accuracy of adjustment of the variable slit, the focus, and the optical axis, and the light intensity decreases at the end of the beam spot. For this reason, the edge of the correction portion is not linear, and for example, there is a problem in removing a black defect formed outside the linear edge portion of the light shielding layer. Further, at the same time as the removal of the defect, the lower substrate is evaporated by about 1 to 5 nm in depth, and the surface of the substrate is roughened by the evaporation. Such surface roughness is caused by KrF excimer laser (wavelength 254 nm) or ArF
When short-wavelength exposure light of an excimer laser (wavelength 193 nm) is used, there is a possibility that the light transmittance may be seriously reduced due to irregular reflection. Further, such a decrease in the light transmittance of the substrate significantly impairs the throughput of exposure using the exposure apparatus. Further, since the exposure time for obtaining the required exposure amount is prolonged, the risk that the exposure mask is deformed due to an increase in temperature is increased. In addition, the beam spot size of the laser beam is about 0.5 μm due to the limit of light condensing property due to diffraction, and it is difficult to cope with finer correction. Transparent shifter defects have problems such as poor photothermal energy conversion efficiency and difficulty in heating and evaporating.

On the other hand, FIB irradiation can cope with finer correction, but it is difficult to remove only the defect precisely when removing an irregular defect, and the ion beam is also applied to the substrate near the defect. Is irradiated to form a deteriorated portion. Specifically, the deteriorated portion is a region where the light transmittance is reduced due to the remaining gallium atoms. S
For the processing residue of the transparent layer made of iO _2, selective removal by FIB assisted etching using xenon fluoride (XeF ₂ ) gas has been proposed. However, in this technique, gallium ions are used. Therefore, the problem of formation of a deteriorated portion cannot be avoided.

Accordingly, the present invention provides a method of correcting a defect of an exposure mask which can eliminate the influence of a deteriorated portion which can be formed in correcting a defect of the exposure mask, a high-performance exposure mask obtained by this method, An exposure method capable of avoiding a fixed defect using an exposure mask, a highly reliable semiconductor device manufactured by applying the exposure method, and a method of manufacturing a semiconductor device capable of manufacturing such a semiconductor device with high yield. The purpose is to do.

[0010]

Means for Solving the Problems In order to achieve the above object, a method for correcting a defect of an exposure mask according to a first aspect of the present invention (hereinafter, referred to as a defect correcting method according to the first aspect).
Is a defect correction method for an exposure mask, which comprises a substrate transparent to exposure light, and corrects a defect of the exposure mask having a light transmitting region and a light shielding region formed on the substrate.
(A) removing a defect remaining in the light transmitting region;
(B) etching the light transmitting region where the defect remains to a predetermined depth. In the present specification, any invention classified as the first aspect relates to a so-called metal light-shielding layer mask, and the defect to be removed is a black defect which is a processing residue of the light-shielding layer.

In the defect repairing method according to the first aspect of the present invention, in the step (a), a focused ion beam (FIB)
In the step (b), etching can be performed to a depth at which a deteriorated portion generated in the light transmission region due to the irradiation of the focused ion beam can be removed. Defect removal may be performed based on the direct sputter etching action of FIB, or in FIB assisted etching in which the chemical reaction between the etching species generated from the etching gas and the defect is promoted using the incident energy of FIB. It may be performed based on this. This is the same in the following description in this specification.

The etching in the step (b) may be performed only on the light transmitting region where the defect remains,
The process may be performed on all the light transmitting regions including the light transmitting region where no defect remains. When the etching is performed only on the light transmission region where the defect remains, the thickness of the substrate is partially reduced. I do not have it, so I do not mind anything. However, if the etching conditions that can secure the selectivity with respect to the light shielding layer are adopted,
Since all the light transmitting regions can be simultaneously etched without forming an etching mask, it is easier in process to etch all the light transmitting regions. According to such a manufacturing method, it is possible to manufacture an exposure mask having no defect and having a high light transmittance in a light transmitting region.

An exposure mask according to a first aspect of the present invention comprises a substrate transparent to exposure light, includes a light transmitting region and a light shielding region formed on the substrate, and remains in the light transmitting region. The light transmission region where the defect is removed and the defect remains is etched to a predetermined depth.

An exposure method according to a first aspect of the present invention is an exposure method for irradiating an exposure mask with exposure light and transferring a pattern formed on the exposure mask to a photoresist layer on a substrate, The exposure mask is formed of a substrate that is transparent to exposure light, includes a light transmitting region and a light blocking region formed on the substrate, and removes defects remaining in the light transmitting region and removes defects. The light transmitting region is etched to a predetermined depth.

The semiconductor device according to the first aspect of the present invention comprises:
The exposure mask is irradiated with exposure light, the pattern formed on the exposure mask is transferred to a photoresist layer on the substrate, and the substrate is processed using a resist mask obtained by developing the photoresist layer. Wherein the exposure mask comprises a substrate transparent to the exposure light, includes a light transmitting region and a light shielding region formed on the substrate, and has a defect remaining in the light transmitting region. Is removed, and
The light transmitting region where the defect remains is etched to a predetermined depth.

In a method of manufacturing a semiconductor device according to a first aspect of the present invention, an exposure mask is irradiated with exposure light, and a pattern formed on the exposure mask is transferred to a photoresist layer on a substrate. A method for manufacturing a semiconductor device, comprising a step of performing a treatment on a substrate using a resist mask obtained by developing a resist layer, wherein the exposure mask comprises a substrate transparent to exposure light, and A light transmitting region and a light shielding region are formed, defects remaining in the light transmitting region are removed, and the light transmitting region where the defect remains is etched to a predetermined depth. .

A defect repair method according to a first aspect of the present invention,
In the exposure mask, the exposure method, the semiconductor device, and the method for manufacturing a semiconductor device, a predetermined depth is used to remove a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect. The depth can be obtained. As a result, in the exposure mask, the light transmittance of the light transmission region becomes higher than before, the occurrence of fixed defects is prevented in the exposure method, and the accuracy and reliability of the circuit pattern are improved in the semiconductor device, In the semiconductor device manufacturing method, the throughput and the manufacturing yield of the semiconductor device are improved.

A defect repair method for an exposure mask according to a second aspect of the present invention (hereinafter referred to as a defect repair method according to a second aspect of the present invention) comprises a substrate transparent to exposure light. A first light-transmitting region formed on the substrate;
A light transmitting area group, a second light transmitting area group formed of another plurality of light transmitting areas formed on the substrate, and an exposure light passing through the first light transmitting area group and a second light transmitting area group a defect correction method for an exposure mask to modify a given defect exposure mask phase difference theta ₁ is generated between the exposure light passed through the,
(A) removing a defect remaining in the light transmitting region;
(B) etching the light transmitting region group including the light transmitting region where the defect remains to a predetermined depth. The specific object to be etched in the above step (b) is a shifter, a substrate, or both.
The shifter is a member that generates a phase difference, and specifically, silicon oxide (SiO ₂ ) formed to a predetermined thickness.
Transparent layer such as a layer, or a molybdenum silicide (MoSi _x) layer formed to a predetermined thickness, molybdenum silicide nitride (MoSi _x N _y) layer, chromium oxide (C
rO) layer, a semi-light-shielding layer made of zirconium oxide (ZrO) based material or the like. When a groove is formed at a predetermined depth in the substrate, a portion of the substrate corresponding to the depth of the groove is also a shifter.

It should be noted that all inventions classified as the second embodiment in this specification relate to a phase shift mask, and the defects to be removed include a black defect which is a processing residue of a light shielding layer and a shifter. These are shifter defects that are processing residues. In the lower shifter type Levenson-type mask to be described later, the shifter has not yet been patterned at the stage of removing the defect in the step (a), so that the first light transmitting region group and the second light transmitting region group are not patterned. However, in the present invention, for the sake of convenience, the “first light transmission region group” and the “second light transmission region group”
The term "light transmission region group" will be used. Further, the phase difference described in this specification means a phase difference between exposure light passing through the first light transmission region group and exposure light passing through the second light transmission region group, unless otherwise specified. And Also, the first
Exposure light that has passed through the light transmission region group or exposure light that has passed through the second light transmission region group may be collectively referred to as “transmitted light”.

In the defect repairing method according to the second aspect of the present invention, specifically, in step (a), defects are removed using a focused ion beam, and in the subsequent step (b), irradiation of the focused ion beam is performed. The etching is performed to such a depth that the deteriorated portion generated in the light transmitting region due to the above can be removed. According to such a manufacturing method, it is possible to manufacture an exposure mask having no defect and having a high light transmittance in a light transmitting region.

Although the defect does not always remain in all the light transmitting regions, after removing the defect, the light transmitting region group including the light transmitting region where the defect remains is etched. Therefore, for example, even if a defect remains in only one of the light transmitting regions included in the first light transmitting region group, after removing the defect, the light transmitting region including no defect remains, All the light transmitting regions included in the first light transmitting region group are etched. The same applies to the second light transmission region group. Of course, a case may occur in which both the first light transmission region group and the second light transmission region group are etched. Thus, the reason that all the light transmitting regions having the same optical characteristics are similarly etched is that the phase shift mask has a function of controlling the phase of the transmitted light, unlike a metal light shielding layer mask that simply controls transmission / shielding. This is because, in order to realize good pattern resolution, in each light transmission region group, the exposure light passing through any light transmission region needs to have the same phase.

By the way, when the light transmitting region group of the phase shift mask is etched to a certain depth, the phase of the exposure light passing through the etched light transmitting region group clearly changes from that before the etching. However, the first light transmission region group and the second light transmission region group
After etching one or both of the light transmitting region groups, the phase difference of the transmitted light between the first light transmitting region group and the second light transmitting region group finally becomes equal to the predetermined phase difference θ _1. The original function of the phase shift mask is maintained as long as it is performed. From this viewpoint, the defect repair method for the exposure mask according to the second aspect of the present invention can be further roughly classified into the following four types of modes 2A to 2D.

In the method of repairing a defect of an exposure mask according to the second aspect, in the step (b), a light transmission region group including a light transmission region in which a defect remains is etched to obtain a predetermined phase difference θ. it is a method to achieve the _1. The etching that is performed to remove the deteriorated portion generated in the light transmission region where the defect remains will be referred to as “removal etching” below. Therefore, the defect repair method according to the second embodiment is a method capable of achieving the predetermined phase difference θ ₁ by only one removal etching. In some cases, in the removal etching in the step (b), the light transmission region group including the light transmission region where the defect has remained is simultaneously etched, and the light transmission region group including the light transmission region where the defect has not remained remains. May be simultaneously etched.

Here, if the phase difference before the removal etching is referred to as “initial phase difference θ ₀ ”, the defect repairing method according to the second embodiment 2A has an initial phase difference θ ₀ and a predetermined phase difference θ _1. And (2A-1) θ ₀ > θ ₁ , (2A-2) θ ₀ = θ ₁ , and (2A-3) θ ₀ <θ _1. , There is. The case (2A-1) is applied when a defect remains only in one of the first light transmission region group and the second light transmission region group, and the phase difference after the removal etching becomes smaller than the initial phase difference θ _0. Is done. Case (2A-2) is applied when the defect remains in both the first light transmission region group and the second light transmission region group, and the phase difference after removal etching is equal to the initial phase difference θ _1. . Further, the case (2A-3)
This is applied when a defect remains in only one of the first light transmission region group and the second light transmission region group, and the phase difference after the removal etching becomes larger than the initial phase difference θ ₁ .

In the defect repairing method according to the 2B aspect, in the step (b), a light transmitting area group including a light transmitting area where a defect remains and a light transmitting area including a light transmitting area where a defect does not remain. A step of achieving a predetermined phase difference by etching the light-transmitting region group and further etching the light-transmitting region group including the light-transmitting region in which the defect remains after the step (b). , Is included. As etching performed in step (c), the etching is performed in order to offset the deviation Δθ from a predetermined phase difference theta ₁ caused by the removal etching, hereinafter, it will be referred to as "adjustment etching". In the defect repair method according to the second B aspect, the following two types of cases are provided according to the magnitude relationship between the initial phase difference and the predetermined phase difference: (2B-1) θ ₀ > θ ₁ , and 2B-2) θ ₀ <θ ₁ .

In the defect repairing method according to the 2C aspect, after the step (b), (c) etching the light transmitting region group including the light transmitting region in which no defect remains, the predetermined Achieving a phase difference. In the step (b), not only the light transmitting region group including the light transmitting region where the defect remains but also the light transmitting region group including the light transmitting region where the defect does not remain may be etched. In the defect repair method according to the 2C aspect, the following three types of cases are performed according to the magnitude relationship between the initial phase difference and the predetermined phase difference, that is, (2C-1) θ ₀ > θ ₁ , (2C− 2) θ ₀ = θ ₁ , and (2C-3) θ ₀ <θ ₁ .

Further, in the defect repairing method according to the 2D aspect, the defect is included in the first light transmitting area and the second light transmitting area.
It remains in both of the light transmitting regions included in the light transmitting region group. In the step (b), both light transmitting region groups are etched. After the step (b), (c) Etching the light transmitting region group again to achieve a predetermined phase difference. The defect repair method according to the 2D aspect includes the following two types of cases according to the magnitude relation between the initial phase difference and the predetermined phase difference: (2D-1) θ ₀ > θ ₁ , and ( 2D-2) θ ₀ <θ ₁ .

It should be noted that which of the light-transmitting regions included in the light-transmitting regions is defective depends on the mask structure.
It depends on the type of process for obtaining the mask structure, and also on the apparatus and process conditions applied to the process.

In any of the exposure mask defect correction methods according to the 2A to 2D modes, the difference between the initial phase difference θ ₀ and the predetermined phase difference θ ₁ (| θ ₀ −θ ₁ |) Is desirably within approximately 10 °, preferably approximately within 5 °.

An exposure mask according to a second aspect of the present invention comprises a first light transmitting area group comprising a plurality of light transmitting areas formed on a substrate transparent to exposure light.
A second plurality of light transmission areas formed on the substrate;
A predetermined phase difference is generated between the exposure light passing through the first light transmission region group and the exposure light passing through the second light transmission region group, and remains in the light transmission region. The defect is removed, and the light transmitting region group where the defect remains is etched to a predetermined depth.

An exposure method according to a second aspect of the present invention is an exposure method for irradiating an exposure mask with exposure light and transferring a pattern formed on the exposure mask to a photoresist layer on a substrate, The exposure mask comprises a substrate transparent to exposure light, a first light transmission region group including a plurality of light transmission regions formed on the substrate, and another plurality of light transmission regions formed on the substrate. A predetermined phase difference is generated between the exposure light passing through the first light transmission area group and the exposure light passing through the second light transmission area group, and the light transmission It is characterized in that a defect remaining in the region is removed, and a light transmitting region group including the light transmitting region in which the defect remains has been etched to a predetermined depth.

The semiconductor device according to the second aspect of the present invention comprises:
The exposure mask is irradiated with exposure light, the pattern formed on the exposure mask is transferred to a photoresist layer on the substrate, and the substrate is processed using a resist mask obtained by developing the photoresist layer. Wherein the exposure mask comprises a substrate transparent to the exposure light, and a first light transmission region group including a plurality of light transmission regions formed on the substrate; A second light transmission area group formed of another plurality of light transmission areas formed between the exposure light passing through the first light transmission area group and the exposure light passing through the second light transmission area group. Has a predetermined phase difference, a defect remaining in the light transmitting region is removed, and a light transmitting region group including the light transmitting region where the defect remains is etched to a predetermined depth. And

In a method of manufacturing a semiconductor device according to a second aspect of the present invention, an exposure mask is irradiated with exposure light, and a pattern formed on the exposure mask is transferred to a photoresist layer on a substrate. A method for manufacturing a semiconductor device, comprising a step of performing a treatment on a substrate using a resist mask obtained by developing a resist layer, wherein the exposure mask comprises a substrate transparent to exposure light, and A first light transmitting region group including a plurality of light transmitting regions formed and a second light transmitting region group including another plurality of light transmitting regions formed on the substrate; A predetermined phase difference is generated between the exposure light that has passed through the second light transmission area group and the exposure light that has passed through the second light transmission area group. The light transmitting area group including the area is etched to a predetermined depth. And wherein the are.

A method for correcting a defect of an exposure mask, an exposure mask, an exposure method, a semiconductor device,
In the method for manufacturing a semiconductor device, the "predetermined depth"
Can be set to a depth at which a deteriorated portion generated in a light transmitting region due to irradiation with a focused ion beam for removing a defect can be removed. As a result, in the exposure mask, the light transmittance of the light transmission region is higher than before the removal, and the occurrence of fixed defects is prevented in the exposure method, and the accuracy and reliability of the circuit pattern are improved in the semiconductor device. In the semiconductor device manufacturing method, the throughput and the manufacturing yield of the semiconductor device are improved. Further, the exposure mask, the exposure method, the semiconductor device, and the semiconductor device manufacturing method according to the second aspect of the present invention include the second A described in relation to the defect repairing method according to the second aspect of the present invention. Modes 2 to 2D can all be applied.

By the way, in the phase shift mask,
In the simplest case, when the phase difference between the exposure lights passing through the adjacent light transmission areas is 180 °, the light intensity becomes zero at the boundary between the two areas, and the effect of improving the resolution is maximized. In any of the inventions according to the aspect, the “predetermined phase difference θ ₁ ” is defined as 180 ° ± 10 °. The reason why the tolerance of ± 10 ° is added is to allow a deviation that does not impair the practical performance of the exposure mask.

In any of the inventions according to the second aspect of the present invention, the phase difference of the transmitted light between the first light transmitting area group and the second light transmitting area group is generated by the shifter in a practical mask structure. are doing. The phase difference of the transmitted light between the first light transmitting area group and the second light transmitting area group is determined by the optical path length of the exposure light passing through the shifter. Therefore, for example, when the predetermined phase difference is 180 °, the thickness of the shifter such that the optical path length becomes equal to １ ／ of the wavelength λ of the exposure light is achieved by the shifter removal etching or the adjustment etching. do it. The shifter thickness d when the phase difference of the transmitted light is 180 ° can be obtained from the following equation. n · d−n ₀ · d = (n−n ₀ ) · d = λ / 2 where n is the refractive index of the shifter, n ₀ is the refractive index of the atmosphere, and n ₀ = 1.

The predetermined phase difference θ ₁ is 180 °
Besides, 60 ° and 90 ° can also be adopted. A phase difference of 60 ° is employed when achieving a phase difference of 180 ° in three stages, and a phase difference of 90 ° is employed when achieving a phase difference of 180 ° in two stages. On the actual exposure mask, for example, along the whole or a part of the edge of the first shifter that achieves a phase difference of 180 °, the angle between the first shifter and the first shifter is 60 ° (120 ° with the region where no shifter exists). A second shifter is provided which achieves a phase difference of 60 ° along all or part of the edge of the second shifter (60 ° with a region where no shifter is present). A third shifter is provided. These series of shifters are called multi-stage shifters (three-stage shifters in the above example), and have the same effect as reducing the edge thickness of a single shifter as a whole. By reducing the thickness of the edge, abrupt phase inversion at the edge portion can be mitigated, and generation of an unnecessary pattern can be prevented. The defect removal method according to the second aspect of the present invention can also be applied to defect correction of an exposure mask having such a multi-stage shifter. For example, in an exposure mask having the above-described three-stage shifter, four types of light transmission are preferably performed in an area where no shifter exists, an area where the first shifter exists, an area where the second shifter exists, and an area where the third shifter exists. An area group will be present. In such a case, adjacent light transmitting region groups are always regarded as a first light transmitting region group and a second light transmitting region group, and the phase difference between these two light transmitting region groups is set to 60 °. Removal etching or adjustment etching may be performed. The same applies when the phase difference is 90 °. However, a predetermined phase difference in the multi-stage shifter can be provided with a tolerance of approximately ± 10 °.

In the method for correcting a defect of an exposure mask, the exposure mask, the exposure method, and the semiconductor device and the method for manufacturing the same according to all aspects of the present invention, the exposure mask may be a master mask, It may be a working mask copied from a master mask.

In the semiconductor device and the method of manufacturing the same according to all aspects of the present invention, examples of the substrate include a semiconductor substrate, a semi-insulating substrate, an insulating substrate, and a layer to be processed formed on these substrates. be able to. As the layer to be processed, specifically, an impurity-containing polysilicon layer; a metal layer made of aluminum, copper, silver, tungsten, or the like; or an alloy layer or compound containing these metal elements; tungsten silicide, titanium silicide, molybdenum silicide A metal silicide layer comprising a metal silicide layer formed on an impurity-containing polysilicon layer;
Polymetal film in which a metal layer is laminated on an impurity-containing polysilicon layer; Insulating layer made of silicon oxide-based material, silicon nitride, silicon oxynitride, silicon oxyfluoride, polyimide, etc .; Ferroelectric made of barium titanate, PZT, etc. Body layer: Examples of any material layer to be processed in manufacturing a normal semiconductor device, such as an oxide layer such as ITO. The structural part formed by the processing may be any structural part that constitutes a normal semiconductor device, such as wiring, electrodes, resistors, capacitors, and openings.

In the semiconductor device and the method of manufacturing the same according to all aspects of the present invention, examples of the processing performed on the substrate include wet etching, dry etching, ion milling, and ion implantation. The semiconductor device manufactured by the method for manufacturing a semiconductor device according to all aspects of the present invention includes a component of an integrated circuit such as a memory element and a logic element, a MIS element, and the like.
Transistor elements such as a transistor and a bipolar transistor; cold cathode field emission devices incorporated in a flat display device (so-called field emission display); You.

[0041]

Embodiments of the present invention (hereinafter, abbreviated as embodiments) will be described below with reference to the drawings.

(Embodiment 1) In Embodiment 1, a method for correcting a defect of an exposure mask according to the first aspect of the present invention, an exposure mask manufactured by the method, and an exposure mask The present invention relates to an exposure method used, a semiconductor device manufactured by applying the exposure method, and a method of manufacturing the same. FIG. 1 shows a conceptual process diagram of the defect repair method according to the first embodiment.

FIG. 1A shows that a light shielding layer 11 made of, for example, chromium is formed on a substrate 10 made of, for example, quartz by 0.35 mm.
It shows a state formed in a line-and-space shape having a width of μm. The area where the light shielding layer 11 is formed is the light shielding area 31, and the area other than the light shielding area 31 is the light transmitting area 30. A processing residue of the light-shielding layer 11 remains as a black defect 20 in a part of the light transmission region 30.

FIG. 1B shows a state in which the black defect 20 has been removed by FIB assisted etching using a focused ion beam (FIB) of gallium. Table 1 below shows an example of FIB assisted etching conditions. Gallium atoms are implanted into the portion of the light transmission region 30 where the black defect 20 remains, and a deteriorated portion 10A is formed. The deteriorated portion 10A is formed over a depth of about 0.01 μm from the surface of the substrate 10 in the light transmission region 30 when the ion acceleration energy of FIB irradiation is set to 20 keV, for example, and the i-line (λ = 365 nm) is reduced by about 10%.

[Table 1] Ion current: 50 pA Ion acceleration energy: 20 keV

Next, as shown in FIG. 1C, the light transmitting region group 300 is etched to a predetermined depth to form a substrate removing portion 10B. An example of the etching conditions is shown in Table 2 below. Here, the predetermined depth is set to 0.05 μm in order to sufficiently remove the deteriorated portion 10A. In the exposure mask PM1 thus obtained, the light transmittance of the light transmission region 30 is restored to a level substantially equal to the original light transmittance of the substrate 10.

[Table 2] Etching apparatus: Parallel plate type RIE (Reactive Ion Etching) apparatus CF ₄ flow rate: 20 SCCM Pressure: 10 Pa RF power: 200 W (13.56 MHz) Etching temperature: 0 ° C.

Next, an exposure method using the exposure mask PM1, a semiconductor device manufactured by applying the exposure method, and a method of manufacturing the semiconductor device will be described with reference to FIG. The base used was a metal layer 42 formed on a semiconductor substrate 40 via an insulating layer 41, as shown in FIG. On the metal layer 42, a photoresist layer 43 is formed. The substrate and the exposure mask PM1 are arranged to face each other, the exposure mask PM1 is irradiated with exposure light, and the line-and-space pattern formed on the exposure mask PM1 is transferred to the photoresist layer 43 on the substrate. I do. In FIG. 2A, the expression is used as if the dimensions of the substrate and the exposure mask PM1 are the same size and the proximity exposure is performed.
This is a convenient expression for simplification, and the exposure method may be contact exposure or reduced projection exposure. In the case of performing the reduced projection exposure, a projection optical system (not shown) is provided between the exposure mask PM1 and the substrate, and the pattern on the exposure mask PM1 is usually reduced at a reduction rate of 1/5 or 1/4. Transferred to upper photoresist layer. In the first embodiment, since the light transmittance of the light transmitting region of the exposure mask PM1 is improved, no fixed defect occurs, and the manufacturing yield of the semiconductor device can be significantly improved.

Next, as shown in FIG. 2B, the photoresist layer 43 is developed to form a resist mask 43A. In the figure, since the positive type photoresist layer 43 is illustrated, the exposed area is dissolved and removed in the developing solution, but the opposite is true for the negative type photoresist layer. Next, as shown in FIG. 2C, the metal layer 42 is etched through the resist mask 43A to form a wiring layer 42A. Further, the resist mask 43A is removed using ashing or a stripping solution to obtain a semiconductor device S1 as shown in FIG. The semiconductor device S1 obtained in this manner includes the wiring layer 42A according to an accurate line-and-space pattern having a width of 0.4 μm.

(Embodiment 2) Embodiment 2 is an example in which the defect correction method for an exposure mask according to the second embodiment A of the present invention is applied to defect correction of a halftone mask, and is manufactured by this method. The present invention relates to an exposure mask, an exposure method using the exposure mask, a semiconductor device manufactured by applying the exposure method, and a method of manufacturing the same.
FIG. 3 shows a conceptual process chart of the defect repair method according to the second embodiment. Note that reference numerals used in FIG. 3 are partially common to those in FIG. 1, and detailed description of common parts is omitted. In all the embodiments after the third embodiment,
In order to distinguish each light transmission region having different optical characteristics, the first
A light transmitting area included in the light transmitting area group is a first light transmitting area,
The light transmitting area included in the second light transmitting area group will be referred to as a second light transmitting area. Furthermore, Embodiment 2 below, in all of the embodiments described herein, the predetermined phase difference theta ₁ and 180 °.

FIG. 3A shows, for example, quartz (refractive index n _1).
= 1.5) on the substrate 10 having a thickness of 0.11
The semi-light-shielding layer 12 made of chromium oxide having a thickness of μm (refractive index n ₂ =
2.5) shows the state formed. Semi-shielding layer 12
Has a square opening having a side length of about 1.75 μm. The inside of the opening, that is, the region where the semi-light-shielding layer 12 is not formed is the first light transmission region 32. First
There are a plurality of light transmitting regions 32, which collectively constitute a first light transmitting region group 320. The area where the semi-light-shielding layer 12 is formed is the second light transmission area 33. There are a plurality of second light transmitting regions 33, which collectively constitute a second light transmitting region group 330. A processing residue of the semi-light-shielding layer 12 remains as a shifter defect 21 in a part of the first light transmission region 32. The thickness of the semi-light-shielding layer 12 is the i-line (λ =
365 nm), the phase difference between the transmitted light of the first light transmitting region group 320 and the transmitted light of the second light transmitting region group 330 is
For example, the thickness is 165 °. That is, the state shown in FIG. 3A corresponds to the case (2A-3) θ ₀ <θ ₁ where the initial phase difference θ ₀ is smaller than the predetermined phase difference θ ₁ .

FIG. 3B shows a state in which the shifter defect 21 has been removed by FIB assisted etching using a focused ion beam (FIB) of gallium. The conditions for this etching are as shown in Table 1 above. In the portion of the first light transmission region 32 where the shifter defect 21 remains,
Gallium atoms are implanted, and a deteriorated portion 10A is formed. The degraded portion 10A is formed over a depth of about 0.01 μm from the surface of the substrate 10 in the first light transmission region 32 when the ion acceleration energy at the time of FIB irradiation is set to 20 keV, for example. Is reduced by about 10%.

Next, as shown in FIG. 3C, the first light transmitting region group 320, specifically, the substrate 10 is etched to a predetermined depth (removal etching) to form a substrate removing portion 10B. I do. The etching conditions are as shown in Table 2 above. Here, the deteriorated portion 10A is sufficiently removed, and
The transmitted light of the first light transmitting area group 320 and the second light transmitting area group 3
30 and a predetermined phase difference θ ₁ (= 1
80 °), a predetermined depth of 0.03μ
m. Exposure mask PM2 thus obtained
In, the light transmittance of the first light transmitting region group 320 is restored to a level substantially equal to the original light transmittance of the substrate 10.

Next, an exposure method using the exposure mask PM2, a semiconductor device manufactured by applying the exposure method, and a method of manufacturing the semiconductor device will be described with reference to FIG. Note that reference numerals used in FIG. 4 are partially common to those in FIG. 2, and detailed description of common portions is omitted. The base used here is an insulating layer 41 formed on a semiconductor substrate 40 as shown in FIG.
On the insulating layer 41, a photoresist 43 is formed. The substrate and the exposure mask PM2 are arranged to face each other, the exposure mask PM2 is irradiated with exposure light, and the pattern of the opening formed in the exposure mask PM2 is transferred to the photoresist layer 43 on the substrate. The exposure method is reduced projection exposure. First light transmission region group 32 of exposure mask PM2
Since the light transmittance of 0 is improved, no fixing defect occurs, and the production yield of the semiconductor device can be greatly improved.

Next, as shown in FIG. 4B, the photoresist layer 43 is developed to form a resist mask 43A. In the figure, since the positive type photoresist layer 43 is illustrated, the exposed area is dissolved and removed in the developing solution, but the opposite is true for the negative type photoresist layer. Next, as shown in FIG. 4C, the insulating layer 41 is etched through the resist mask 43A to form an opening 41A. Further, the resist mask 43A is removed by using ashing or a stripping solution to obtain a semiconductor device S2 as shown in FIG. In the semiconductor device S2 thus obtained, a substantially circular opening 41A having a diameter of 0.35 μm is accurately formed.

(Embodiment 3) Embodiment 3 is an example in which the defect correction method for an exposure mask according to the second aspect of the present invention is applied to defect correction for a halftone mask. First, an example of a combination of removal etching and adjustment etching in the halftone mask defect repair method is shown in Table 3 below.
Shown in However, the target of the adjustment etching is the semi-light-shielding layer. Table 3 also shows a method for correcting a defect of the exposure mask according to the second embodiment of the present invention.

[Table 3]

In the table, “↑” indicates that the initial thickness of the semi-light-shielding layer 12 is larger than the thickness that achieves the predetermined phase difference θ ₁ , or that the phase difference θ _E after the removal etching has the predetermined phase difference θ _E. It indicates that greater than theta _1. “↑↑” indicates that the phase difference θ _E after the removal etching is further increased when the initial thickness of the semi-light-shielding layer 12 is larger than the thickness that achieves the predetermined phase difference θ ₁ . “↓” indicates that the initial thickness of the semi-light-shielding layer 12 is smaller than the thickness that achieves the predetermined phase difference θ ₁ , or that the phase difference θ _E after etching is smaller than the predetermined phase difference θ _1. . The “aspect” refers to the aspect of the present invention described in the section of “Means for Solving the Problems” in this specification. Note that these items described in Table 3 are common to Table 4 described later.

The case (2C-1) and the case (2C-
FIG. 5 shows a process chart of the halftone mask defect repair method according to 2). The reference numerals used in FIG. 5 are the same as those in FIG.
The second embodiment is almost the same as the second embodiment except that the initial thickness is different. In FIG. 5A, the case where the initial thickness of the semi-light-shielding layer 12 is a thickness that achieves a predetermined phase difference θ ₁ corresponds to the case (2C-2), and the initial thickness of the semi-light-shielding layer 12 Is larger than the thickness that achieves the predetermined phase difference θ ₁ , corresponds to case (2C-1). In these cases, the shifter defect 21 is removed in the first light transmission region 32 (see FIG. 5B), and the first light transmission region group 320 (more specifically, the substrate 10) is removed and etched. Therefore, the phase difference θ _E after the removal etching necessarily increases (see FIG. 5C).

Then, as a process not performed in the second embodiment, the semi-light-shielding layer 12 is adjusted and etched to adjust the phase difference to a predetermined phase difference θ ₁ (FIG. 5).
(D)). The exposure mask obtained in this manner can be applied to the exposure method similarly to the exposure mask PM2 obtained in the second embodiment, and can be suitably used for a method of manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

The initial thickness of the semi-light-shielding layer 12 has a predetermined phase difference θ.
_The case (2C-3) that is thinner than the thickness that achieves ₁ is not shown, but, in brief, in the process shown in FIG.
Deep etching to make the phase difference a predetermined phase difference θ
_When it becomes larger than _{1, this corresponds} to a case where the half-shielding layer 12 is adjusted and etched to adjust the phase difference to a predetermined phase difference θ ₁ .

It should be noted that the above-described defect repair methods for the halftone mask all relate to the removal of the shifter defect 21 remaining in the first light transmitting region 32, but the second light transmitting region 33
(More specifically, removal of a defect remaining on the semi-light-shielding layer 12) is not particularly assumed. The reason is that the semi-shielding layer 12
This is because a defect that can remain on the mask is generally a residual film of a resist mask (not shown) used when patterning the semi-light-shielding layer 12. It is usually difficult to remove the remaining film of the resist mask using the FIB. Therefore, a deteriorated portion is formed in the semi-light-shielding layer 12, and it is not necessary to remove the deteriorated portion.

(Embodiment 4) Embodiment 4 is an example in which the defect correction method for an exposure mask according to the embodiment 2A of the present invention is applied to defect correction for an upper shifter type Levenson-type mask. FIG. 6 shows a conceptual process chart of the defect repair method according to the fourth embodiment. The reference numerals used in FIG. 6 are partially common to those in FIG.

FIG. 6A shows, for example, quartz (refractive index n _1).
= 1.5), a light-shielding layer 11 made of chromium is formed in a line-and-space shape having a width of, for example, 1.25 μm, and a space between the adjacent light-shielding layers 11 is made of, for example, spin-on glass ( SOG) (refractive index n ₂ =
This shows a state in which the transparent layers 13 of 1.5) having a thickness of 0.228 μm are alternately formed. The area where the transparent layer 13 is not formed is the first light transmission area 34. There are a plurality of first light transmitting regions 34, which collectively constitute a first light transmitting region group 340. The area where the transparent layer 13 is formed is the second light transmission area 35. There are a plurality of second light transmitting regions 35, which collectively constitute a second light transmitting region group 350. Between the first light transmitting region 34 and the second light transmitting region 35, there is a light shielding region caused by the light shielding layer 11. A processing residue of the transparent layer 13 remains as a shifter defect 21 in a part of the first light transmission region 34. The thickness of the transparent layer 13 is such that the initial phase difference θ ₀ is smaller than a predetermined phase difference θ ₁ , for example, the first light when using KrF excimer laser exposure light (λ = 248 nm). The thickness is such that the phase difference between the transmitted light of the transmission region group 340 and the transmission light of the second light transmission region group 350 is, for example, 170 °. That is, the state shown in FIG.
₀ predetermined case to be smaller than the phase difference theta ₁ (2A-
3) It corresponds to θ ₀ <θ ₁ .

FIG. 6B shows a state in which the shifter defect 21 has been removed by FIB-assisted etching using a focused ion beam (FIB) of gallium. The conditions for this etching are as shown in Table 1 above. In the portion of the first light transmission region 34 where the shifter defect 21 remains,
Gallium atoms are implanted, and a deteriorated portion 10A is formed.

Next, as shown in FIG. 6C, a resist mask 16 covering the transparent layer 13 is formed, and the first light transmitting region group 340, specifically, the substrate 10 is brought to a predetermined depth. Etching (removal etching) is performed to form a substrate removal portion 10B. The etching conditions are as shown in Table 2 above. Here, in order to sufficiently remove the deteriorated portion 10A and to adjust the phase difference between the first light transmission region group 340 and the second light transmission region group 350 to a predetermined phase difference θ ₁ , The depth is set to 0.02 μm. Finally, resist mask 1
6 is obtained, an exposure mask as shown in FIG. 6D is obtained. In the exposure mask thus obtained, the light transmittance of the first light transmitting region group 340 is restored to a level substantially equal to the original light transmittance of the substrate 10. Such an exposure mask can be applied to the exposure method similarly to the exposure mask PM2 obtained in the second embodiment, and can be suitably used for a method of manufacturing a semiconductor device. In a semiconductor device obtained by such a manufacturing method, 0.1.
A line-and-space pattern having a width of 25 μm is accurately formed, and high reliability is achieved.

In the above-described upper shifter-type Levenson-type defect repair method, the removal of defects remaining in the second light transmission region 35 (more specifically, on the transparent layer 13) is particularly assumed. Absent. The reason for this is that defects that may remain on the transparent layer 13 are generally residual films of a resist mask (not shown) used when patterning the transparent layer 13. It is usually difficult to remove the remaining film of the resist mask using the FIB. Therefore, a deteriorated portion is not formed in the transparent layer 13, and it is not necessary to remove the deteriorated portion.

(Fifth Embodiment) A fifth embodiment is an example in which the defect correction method for an exposure mask according to the second aspect of the present invention is applied to the defect correction of an upper shifter type Levenson-type mask. The combination pattern of the removal etching and the adjustment etching in the halftone mask defect correction method is as shown in Table 3 above. However, the target of the adjustment etching is the transparent layer.

The case (2C-1) and the case (2C-
FIG. 7 shows a process chart of the defect correction method for the upper shifter type Levenson-type mask according to 2). The reference numerals used in FIG. 7 are the same as those in FIG. 6, and the procedure of the process is also substantially the same as that of the fourth embodiment except that the initial thickness of the transparent layer 13 is different and the adjustment etching is performed last. It is. In FIG. 7A, the case where the initial thickness of the transparent layer 13 is a thickness that achieves a predetermined retardation θ ₁ is the case (2C).
Case (2C- 2), in which the initial thickness of the transparent layer 13 is larger than the thickness that achieves the predetermined retardation θ _1.
This corresponds to 1). In these cases, the shifter defect 21 is removed in the first light transmission region 34 (see FIG. 7B), and then the first light transmission region group 340 (more specifically, the substrate 10) is removed and etched. Is performed, the phase difference θ _E after the removal etching is inevitably increased (see FIG. 7C).

Then, as a process not performed in the fourth embodiment, the transparent layer 13 is subjected to adjustment etching to adjust the phase difference to a predetermined phase difference θ ₁ (= 180 °) (FIG. 7). (D)). The exposure mask thus obtained is also the exposure mask P obtained in the second embodiment.
It can be applied to an exposure method similarly to M2, and can be suitably used for a method of manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

The initial thickness of the transparent layer 13 has a predetermined retardation θ ₁
Although the case (2C-3) thinner than the thickness that achieves the above is not shown, the fourth embodiment is simply described.
In the process shown in FIG. 6, the removal etching of the substrate 10 is performed deeply so that the phase difference becomes a predetermined phase difference θ _1.
If it becomes larger than this, it corresponds to the case where the adjustment of the transparent layer 13 is performed to adjust the phase difference to the predetermined phase difference θ ₁ . In the adjustment etching in this case, it is not particularly necessary to cover the first light transmitting region 34 (specifically, the substrate 10) with a resist mask. Because the transparent layer 13
Is generally faster than the constituent material of the substrate 10. Adjustment etching is
It can also be performed by wet etching using a hydrofluoric acid aqueous solution.

Embodiment 6 Embodiment 6 is an example in which the defect correction method for an exposure mask according to the second embodiment of the present invention is applied to defect correction for a lower shifter type Levenson-type mask. 8 and 9 show conceptual process diagrams of the defect repair method according to the sixth embodiment. The reference numerals used in FIG. 8 and FIG. 9 are partially the same as those in FIG.

FIG. 8A shows, for example, quartz (refractive index n _1).
= 1.5) on a substrate 10 made of, for example, SOG (refractive index n ₂ = 1.5).
A 28 μm line-shaped transparent layer 14 is formed with a space of 1.25 μm, and a light-shielding layer 11 made of, for example, chrome is formed on each transparent layer 14 by a line having a width of, for example, 1.25 μm.
This shows a state formed in an and space shape. The region where the transparent layer 14 is not formed is the first light transmitting region 3
4, the first light transmitting regions 34 collectively constitute a first light transmitting region group 340. The region where the transparent layer 14 is formed is the second light transmitting region 35, and the second light transmitting region 35 collectively constitutes a second light transmitting region group 350. Between the first light transmitting region 34 and the second light transmitting region 35, there is a light shielding region caused by the light shielding layer 11. In a part of the first light transmitting region 34, the processing residue of the transparent layer 14 is
It remains as 1. The thickness of the transparent layer 14 is, for example, KrF excimer laser exposure light (λ = 248 nm).
Is used, the transmitted light of the first light transmitting region group 340 and the second
The phase difference of the transmitted light of the light transmitting region group 350 is, for example, 170
°. That is, the state shown in FIG. 8A corresponds to the case (2A-3) θ _E <θ ₁ where the initial phase difference θ ₀ is smaller than the predetermined phase difference θ ₁ .

FIG. 8B shows a state in which the shifter defect 21 has been removed by FIB assisted etching using a focused ion beam (FIB) of gallium and a fluorine-based gas. First light transmission region 34 in which shifter defect 21 remains
Gallium atoms are implanted into
Is formed.

Next, as shown in FIG. 8C, a resist mask 16 for covering the transparent layer 13 is formed, and the first light transmitting region group 340, more specifically, the substrate 10 is formed at a predetermined depth. (Removal etching), the substrate removing portion 10B
To form The etching conditions are as shown in Table 2 above. Here, the predetermined depth is set to 0.02 μm in order to sufficiently remove the deteriorated portion 10A and adjust the phase difference to a predetermined phase difference θ ₁ (= 180 °). Finally, when the resist mask 16 is removed, an exposure mask as shown in FIG. 8D is obtained. In the exposure mask thus obtained, the light transmittance of the first light transmitting region group 340 is restored to a level substantially equal to the original light transmittance of the substrate 10. Such an exposure mask is also described in Embodiment 2.
It can be applied to an exposure method in the same manner as the exposure mask PM2 obtained in the above, and can be suitably used for a method of manufacturing a semiconductor device. In a semiconductor device obtained by such a manufacturing method, a line-and-space pattern having a width of 0.25 μm is accurately formed, and high reliability is achieved.

By the way, in the lower shifter type Levenson-type mask, before patterning the transparent layer 14, the black defect 20 which is a processing residue of the light shielding layer 11 may be removed on the transparent layer 14 in some cases. . However, it is usually difficult to imagine removing the black defect 20 in the same step as the shifter defect 21 described above. A typical process in such a case is shown in FIG. FIG. 9A shows a state in which a transparent layer 14 having a thickness that achieves a predetermined phase difference θ ₁ (= 180 °) is formed on the substrate 10, and the light shielding film 11 is patterned on the transparent layer 14. Is shown. The first light transmitting region 34 and the second light transmitting region 35 are adjacent to each other in the light shielding layer 1.
Alternately occupies one space. At the stage shown in FIG. 9A, since the transparent layer 14 has not been patterned yet, there is no phase difference between the first light transmitting region group 340 and the second light transmitting region group 350. However, even at such a stage, for convenience, the names of both light transmission region groups will be distinguished as described above. Here, a processing residue of the light shielding film 11 remains as a black defect 20 in a part of the second light transmission region 35.

Then, the black defect 20 is removed by FIB assisted etching (see FIG. 9B), and then the etching of the degraded portion 14A caused by the removal of the black defect 20 is performed to remove the transparent layer. The portion 14B is formed (see FIG. 9C). The thickness of the transparent layer 14 at the stage when the removal etching is completed is smaller than the thickness that achieves the predetermined retardation θ ₁ . That is, the phase difference θ _E after the removal etching is necessarily smaller than θ ₁ . Next, using a not-shown resist mask, the transparent layer 14 is removed at every other space between the adjacent light-shielding layers 11 (see FIG. 9D). At this stage, a phase difference occurs between the first light transmission region group 340 and the second light transmission region group 350 for the first time. FIG. 9D shows a state in which the processing residue of the transparent layer 14 remains in the first light transmitting region 34 as the shifter defect 21 with the etching at this time. The state shown in FIG. 9D can be obtained by focusing only on the phase difference between the light transmission region groups, as shown in FIG.
This is the same as the state shown in FIG. Therefore, thereafter, the shifter defect 2 is performed in the same manner as described above with reference to FIG.
9 and removal etching of the deteriorated portion (not shown), and finally the phase difference may be adjusted to a predetermined phase difference θ ₁ (= 180 °) as shown in FIG. .

(Embodiment 7) Embodiment 7 is an example in which the defect correction method for an exposure mask according to Embodiment 2C of the present invention is applied to defect correction for a lower shifter type Levenson-type mask. First, the combination pattern of the removal etching and the adjustment etching in the defect correction method for the lower shifter type Levenson-type mask is as shown in Table 3 above. However, the target of the adjustment etching is the transparent layer.
In the case of the seventh embodiment, the “initial thickness of the shifter” may be the thickness of the shifter that has not been etched at all as shown in FIG. As shown, the thickness may be the thickness of the shifter remaining after the etching.

The case (2C-1) and the case (2C-
FIG. 10 shows a process chart of the method for correcting a defect of the lower shifter type Levenson-type mask according to 2). The reference numerals used in FIG. 10 are the same as those in FIG. 8, and the procedure of the process is also substantially the same as in the sixth embodiment except that the thickness of the transparent layer 14 is different and the final adjustment etching is performed. is there. In FIG. 10A, the case where the initial thickness of the transparent layer 14 is a thickness that achieves the predetermined retardation θ ₁ is the case (2).
Case (2C-2), which corresponds to C-2) and the case where the initial thickness of the transparent layer 14 is thicker than the thickness that achieves the predetermined retardation θ _1.
This corresponds to 1). In these cases, the shifter defect 21 is removed in the first light transmission region 34 (FIG. 10B).
After that, since the first light transmitting region group 340 (more specifically, the substrate 10) is subjected to the removal etching, the phase difference θ _E after the removal etching is necessarily larger than θ ₀ (see FIG. 10). (C)).

Then, as a process not performed in the sixth embodiment, the transparent layer 14 is adjusted and etched to adjust the phase difference to a predetermined phase difference θ ₁ (= 180 °) (FIG. 10). (D)). In the adjustment etching in this case, the first light transmitting region 34 (specifically, the substrate 1
It is not particularly necessary to cover 0) with a resist mask. This is because the etching rate of the SOG that forms the transparent layer 14 is generally faster than the constituent material of the substrate 10.
Adjustment etching can also be performed by wet etching using a hydrofluoric acid aqueous solution. The exposure mask obtained in this manner can be applied to the exposure method similarly to the exposure mask PM2 obtained in the second embodiment, and can be suitably used for a method of manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

The initial thickness of the transparent layer 14 has a predetermined retardation θ ₁
The case (2C-3) that is thinner than the thickness that achieves the above condition is not shown in the drawings.
In the process shown in FIG. 8, the substrate 10 is subjected to deep etching for removal, and the phase difference is reduced to a predetermined phase difference θ _1.
If it is larger than this, it corresponds to the case where the transparent layer 14 is adjusted and etched to adjust the phase difference to a predetermined phase difference θ ₁ .

(Eighth Embodiment) An eighth embodiment is an example in which the defect repair method for an exposure mask according to the second aspect of the present invention is applied to the defect repair of a substrate-engraving type Levenson-type mask. FIG. 11 shows a conceptual process chart of the defect repair method according to the eighth embodiment. The reference numerals used in FIG. 11 are partially the same as those in FIG.

FIG. 11A shows, for example, quartz (refractive index n
₁ = 1.5), a light-shielding layer 11 made of, for example, chromium is formed in a line-and-space shape having a width of, for example, 1.25 μm, and every other space between the adjacent light-shielding layers 11 is formed. The figure shows a state in which the substrate 10 is carved and a groove 15 having a depth of 0.228 μm is formed. The area where the groove 15 is formed is the first light transmitting area 3
6, the first light transmitting regions 36 collectively constitute a first light transmitting region group 360. The area where the groove 15 is not formed is the second light transmission area 37, and the second light transmission area 3
7 collectively constitute a second light transmission region group 370. First
Between the light transmitting region 36 and the second light transmitting region 37, there is a light shielding region caused by the light shielding layer 11. Second light transmission area 3
7, the processing residue of the light shielding layer 11 remains as a black defect 20. When the KrF excimer laser exposure light (λ = 248 nm) is used, the depth of the groove 15 is determined by the transmission light of the first light transmission region group 360 and the second light transmission region group 37.
The thickness is such that the phase difference of the transmitted light of 0 is, for example, 190 °. That is, the state shown in FIG. 11A corresponds to the case (2A-1) θ ₀ > θ ₁ where the initial phase difference θ ₀ is set to be larger than the predetermined phase difference θ ₁ .

FIG. 11B shows a state in which the black defect 20 has been removed by FIB assisted etching using a focused ion beam (FIB) of gallium and a fluorine-based gas. Gallium atoms are implanted into the portion of the second light transmission region 37 where the black defect 20 remains, thereby forming the deteriorated portion 10A.

Therefore, as shown in FIG.
A resist mask 16 covering the light transmitting region group 360 is formed, and the second light transmitting region group 370, specifically, the substrate 10 is etched to a depth of 0.02 μm (removal etching). By this removal etching, the deteriorated portion 10A is removed, and the phase difference between the transmitted light of the first light transmitting region group 360 and the transmitted light of the second light transmitting region group 370 becomes a predetermined phase difference θ ₁ (= 180 °). ). Finally, when the resist mask 16 is removed, an exposure mask as shown in FIG. 11D is obtained. In the exposure mask thus obtained, the light transmittance of the second light transmission region group 370 is
The light transmittance is restored to a level substantially equal to the original light transmittance of the substrate 10. This exposure mask is applied to the exposure method similarly to the exposure mask PM2 obtained in the second embodiment.
It can be suitably used for a method for manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

Ninth Embodiment A ninth embodiment is a modification of the eighth embodiment. The difference between the ninth embodiment and the eighth embodiment is that the initial depth of the groove 15 is a predetermined phase difference θ _1.
[Corresponding to the case (2A-2)], and in addition to the remaining of the black defect 20 in a part of the second light transmitting area 37, a part of the first light transmitting area 36 is formed. This is also the point where the shifter defect 21 remains. The defect repair method according to the ninth embodiment will be described with reference to FIG.
The following description focuses on the differences.

In FIG. 12A, a predetermined phase difference θ
It grooves 15 of depth 0.248μm to achieve ₁ substrate 10
In the first light transmitting region 36 (more specifically, in the groove 15), the shifter defect 2 which is a processing residue of the substrate 10 is formed.
1 remains, and the black defect 20 which is a processing residue of the light shielding layer 11 is formed in the second light transmitting region 37 (more specifically, on the substrate 10).
Remains.

Therefore, as shown in FIG.
The black defect 20 and the shifter defect 21 are removed by IB assisted etching. Gallium atoms are implanted into the portion of the first light transmitting region 36 where the shifter defect 21 remains and the portion of the second light transmitting region 37 where the black defect 20 remains, thereby forming the deteriorated portion 10A. You.

Next, as shown in FIG.
The light transmitting region group 360 and the second light transmitting region group 370 are etched to such an extent that the deteriorated portion 10A can be sufficiently removed (removal etching). At this time, the first light transmission area group 36
0, a deeper groove 15B is formed, and a substrate removing portion 10B is formed in the second light transmitting region group 370. In any of the light transmitting region groups 360, 370, the object to be etched is made of a common material. Therefore, the removal depths are equal, and thus the phase difference remains unchanged at the depth that achieves the predetermined phase difference θ ₁ (= 180 °). Therefore, the state shown in FIG. 12C is a completed state of the exposure mask of the ninth embodiment. Such an exposure mask can be applied to the exposure method similarly to the exposure mask PM2 obtained in the second embodiment, and can be suitably used for a method of manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

Since the defect removing method according to the second aspect of the present invention achieves a predetermined phase difference by only one removing etching, as in the eleventh embodiment,
If the initial phase difference θ ₀ is equal to the predetermined phase difference θ ₁ , all places (here, the substrate 10)
And the groove 15) is subjected to removal etching. Therefore, in the above-described example, the black defect 20 and the shifter defect 21 remain on both the substrate 10 and the groove 15.
When the black defect 20 remains only on the upper part,
The same process is performed when the shifter defect 21 remains only in the region 5.

(Embodiment 10) The embodiment 10 is still another modification of the embodiment 8. The tenth embodiment is different from the eighth embodiment in that the depth of the groove 15 is smaller than the depth at which the predetermined phase difference θ ₁ is achieved (the initial phase difference θ ₀ is, for example, 160 °) [case ( 2A-3)], and the shifter defect 21 remains in the first light transmission region 36. The defect repair method according to the tenth embodiment will be described with reference to FIG. 13 focusing on the differences from the eighth embodiment.

In FIG. 13A, a predetermined phase difference θ
0.228 μm groove 15 shallower than the depth to achieve _1.
Is formed on the substrate 10, and a shifter defect 21 which is a processing residue of the substrate 10 remains in a part of the first light transmission region 36. Next, when the shifter defect 21 is removed by FIB assisted etching, as shown in FIG. 13B, a deteriorated portion 10A is formed in the first light transmission region 36 where the shifter defect 21 remains. Next, as shown in FIG. 13C, the second light transmitting region group 37 is
6 and the second light transmission area group 370 is set to 0.02 μm.
Etch to a depth of m (removal etching). By this removal etching, the deteriorated portion 10A is removed, and the phase difference between the transmitted light of the second light transmitting region group 370 and the transmitted light of the first light transmitting region group 360 becomes a predetermined phase difference θ ₁ (= 1).
80 °). Finally, when the resist mask 16 is removed, an exposure mask as shown in FIG. 13D is obtained. Such an exposure mask can be applied to the exposure method similarly to the exposure mask PM2 obtained in the second embodiment, and can be suitably used for a method of manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

(Embodiment 11) Embodiment 11 is an example in which the defect repair method for an exposure mask according to the mode 2B of the present invention is applied to the defect repair of a substrate-engraved type Levenson-type mask. First, Table 4 below shows an example of a combination of removal etching and adjustment etching in the method of repairing a defect in a Levenson-type mask of a substrate engraving type.
Table 4 also shows a method for correcting a defect of the exposure mask according to the second embodiment of the present invention. In Table 4, regarding the remaining location of the defect, “○” indicates that the defect remains, and “−”
Indicates that no residue remains. In addition, regarding the target of the removal etching, “」 ”indicates that the removal etching is performed,
"-" Indicates that removal etching is not performed. Further, regarding the target of the adjustment etching, “○” indicates that the adjustment etching is performed, and “−” indicates that the adjustment etching is not performed.

[Table 4]

FIG. 14 shows a process chart of the defect correcting method according to the eleventh embodiment. In FIG. 14A, the groove 15
Is greater than the depth at which the predetermined phase difference θ ₁ is achieved. That is, in the state shown in FIG. 14A, the case where the initial phase difference θ ₀ is larger than the predetermined phase difference θ ₁ (2B
-1) It corresponds to θ ₀ > θ ₁ . The black defect 20 is
Remains on top. Therefore, the black defect 20 is removed in the second light transmission region 37 (see FIG. 14B), and then the first light transmission region group 360 and the second light transmission region group 370
(More specifically, the removal etching of both the groove 15 and the substrate 10) is performed. The phase difference θ _E after the removal etching is not different from the initial phase difference θ ₀ (see FIG. 14C). The groove 15 becomes a deeper groove 15B. Next, as shown in FIG. 14D, the first light transmitting region group 360 is covered with a resist mask 16, and further the second light transmitting region group 370 is formed.
More specifically, the substrate 10 is etched (adjusted etching), and the phase difference is adjusted to a predetermined phase difference θ ₁ (= 180 °). Finally, the resist mask 16 is removed to obtain an exposure mask shown in FIG. Such an exposure mask is also the same as the exposure mask PM2 obtained in the second embodiment.
It can be applied to an exposure method in the same manner as described above, and can be suitably used for a method of manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

The defect repairing method according to the embodiment 2B of the present invention is a method of removing a defect after performing removal etching on all locations (here, the substrate 10 and the groove 15) regardless of the remaining defect. This is a method of performing adjustment etching for the remaining location. Therefore, contrary to the example described in the eleventh embodiment, when the initial phase difference θ ₀ is smaller than the predetermined phase difference θ ₁ and the shifter defect 21 remains only in the groove 15, the substrate 10 and the groove 15 The method of performing the adjustment etching on the groove 15B after performing the removal etching on both of them is also the defect correction method according to the embodiment 2B of the present invention.

(Twelfth Embodiment) A twelfth embodiment is an example in which the defect correction method for an exposure mask according to the 2C aspect of the present invention is applied to the defect correction of a Levenson-type mask of a substrate engraving type. FIG. 15 shows a process chart of the defect repairing method according to the twelfth embodiment. In FIG. 15A, the case where the depth of the groove 15 is deeper than the depth that achieves the predetermined phase difference θ ₁ corresponds to the case (2C-1), and the depth of the groove 15 is the predetermined phase difference θ. _The case where the depth is equal to ₁ corresponds to the case (2C-2). In these cases, the shifter defect 21 is removed in the first light transmission region 36 (see FIG. 15B), and then the first light transmission region group 360
And the second light transmission region group 370 (more specifically, the groove 15 and the substrate 10) are subjected to removal etching, so that the phase difference θ _E after the removal etching remains the initial phase difference θ ₀ (FIG. 15). (C)). The groove 15 is a deeper groove 1
5B. Next, as shown in FIG.
The light transmitting region group 360 is covered with the resist mask 16, and further the second light transmitting region group 360 (more specifically, the substrate 1
0) is etched (adjustment etching), and the phase difference is adjusted to a predetermined phase difference θ ₁ (= 180 °). Finally, the resist mask 16 is removed to obtain an exposure mask shown in FIG. Such an exposure mask is also described in Embodiment 2.
It can be applied to an exposure method in the same manner as the exposure mask PM2 obtained in the above, and can be suitably used for a method of manufacturing a semiconductor device. The semiconductor device obtained by such a manufacturing method includes:
It has an accurate circuit pattern and has excellent reliability.

In the twelfth embodiment, the removal etching may be performed only on the groove 15. However, groove 1
When performing the removal etching of only 5, the second light transmission region group 360 needs to be covered with a resist mask.
In addition, the defect repair method for an exposure mask according to the 2C aspect of the present invention is, so to speak, after performing removal etching on at least the remaining portion of the black defect, performing adjustment etching on the portion where the black defect did not remain. There are several other patterns. For example, if the initial phase difference theta ₀ is greater than a predetermined phase difference theta _1, or a predetermined phase difference theta ₁ equally, if black defect 20 was left only on the substrate 10, and covers only the substrate 10 After performing the removed etching, the adjustment etching for the groove 15 can be performed. Also, if the initial phase difference theta ₀ is equal to a predetermined phase difference theta _1, or a predetermined smaller than the phase difference theta _1,
If the shifter defect 21 remains in the groove 15, the groove 1
After performing removal etching only on the substrate 5, the substrate 1
Adjustment etching for 0 can be performed. Further, when the initial phase difference θ ₀ is smaller than the predetermined phase difference θ ₁ and the black defect 20 remains only on the substrate 10,
After the removal etching is performed on both of the substrate 10 and the groove 15 or only the substrate 10, the groove 15 (or 15B) is removed.
Adjustment etching can be performed for the target.

(Thirteenth Embodiment) A thirteenth embodiment is an example in which the defect correction method for an exposure mask according to the second aspect of the present invention is applied to the defect correction of a substrate-engraving type Levenson-type mask. FIG. 16 shows a process chart of the defect correcting method according to the thirteenth embodiment. In FIG. 16A, the depth of the groove 15 is smaller than the depth at which the predetermined phase difference θ ₁ is achieved. That is, the initial phase difference θ ₀ is, for example, 170 °. In the state shown in FIG. 16A, the case where the initial phase difference θ ₀ is smaller than the predetermined phase difference θ ₁ (2D-
This corresponds to 3). The black defect 20 remains on the substrate 10, and the shifter defect 21 remains in the groove 15. Therefore, the second
The black defect 20 is removed in the light transmission region 37, and the shifter defect 21 is removed in the first light transmission region 36 (see FIG. 16B). Thereafter, the first light transmission region group 360 and the second light transmission region
The light transmitting region group 370 (more specifically, the groove 15 and the substrate 1
0) Both removal etchings are performed. The phase difference θ _E after the removal etching remains the initial phase difference θ ₀ (see FIG. 16C). The groove 15 becomes a deeper groove 15B. Next, as shown in FIG. 16D, the second light transmission region group 370 is covered with the resist mask 16, and the first light transmission region group 360 (more specifically, the groove 15) is etched ( Adjustment etching), the phase difference is set to a predetermined phase difference θ ₁
(= 180 °). The groove 15B becomes even deeper. Finally, the resist mask 16 is removed, and FIG.
6 (E) is obtained. Such an exposure mask can be applied to the exposure method similarly to the exposure mask PM2 obtained in the second embodiment, and can be suitably used for a method of manufacturing a semiconductor device. A semiconductor device obtained by such a manufacturing method has an accurate circuit pattern and is excellent in reliability.

The defect repair method according to the 2D aspect of the present invention is different from the defect repair method according to the second embodiment in that the initial phase difference θ ₀ is different from the predetermined phase difference θ ₁ and both locations (here, on the substrate 10 and the groove 1).
In the case where a defect remains in (5), after performing removal etching on both locations, adjustment etching is performed on one location. Therefore, contrary to the example described in the thirteenth embodiment, the initial phase difference θ ₀ is larger than the predetermined phase difference θ ₁ , and the black defect 20 and the shifter defect 21 remain on the substrate 10 and in the groove 15, respectively. In this case, the method of performing the removal etching on both the substrate 10 and the groove 15 and then performing the adjustment etching on the substrate 10 is also the defect repairing method according to the 2D aspect of the present invention. .

The present invention has been described based on the embodiments of the present invention, but the present invention is not limited to these embodiments. For example,
When the exposure mask is a phase shift mask, the present invention is not limited to the above-described halftone mask and various Levenson masks, and basically covers any mask structure as long as it has a substrate and a shifter. can do. For example, a transparent layer for phase inversion not directly contributing to the pattern formation is provided around the opening of the light-shielding layer, and a so-called auxiliary pattern type mask that sharply changes the light area intensity at the opening end, or without using the light-shielding layer A so-called shifter light-shielding mask that forms a light intensity distribution only by devising the arrangement of the phase inversion transparent layer may be used. In addition, the dimensions and constituent materials of each part of the above-described exposure mask, the conditions for removing defects used for defect correction, the conditions for removing etching, the conditions for adjusting etching, and the like are merely examples, and can be appropriately changed, selected, and combined. is there. The exposure method described in the embodiment of the invention, the semiconductor device manufactured by applying the exposure method, and the manufacturing method thereof are also examples, and can be appropriately changed.

[0102]

As is clear from the above description, according to the defect correcting method for the exposure mask (metal light shielding layer mask) according to the first aspect of the present invention, the first aspect of the present invention In the exposure mask according to the present invention, the light transmittance of the light transmission region becomes higher than before, no fixed defect occurs in the exposure method, and the accuracy and reliability of the circuit pattern in the semiconductor device are improved. In the device manufacturing method, the throughput and the manufacturing yield of the semiconductor device are improved.

According to the defect correcting method for the exposure mask (phase shift mask) according to the second aspect of the present invention, there is no defect, the light transmittance of the light transmitting area is high, and the phase control information is It becomes possible to manufacture a well-maintained exposure mask. In an exposure mask, an exposure method, a semiconductor device, and a method of manufacturing a semiconductor device according to a second aspect of the present invention,
The light transmittance of the light transmitting region is higher than before, no fixed defects occur in the exposure method, the accuracy and reliability of the circuit pattern are improved in the semiconductor device, and the throughput and the efficiency are improved in the method of manufacturing the semiconductor device. The manufacturing yield of the semiconductor device is improved.

[Brief description of the drawings]

FIG. 1 is a process chart showing a method for correcting a defect of an exposure mask according to a first embodiment.

FIG. 2 is a schematic view illustrating an exposure method using a mask for exposure, a method for manufacturing a semiconductor device, and a semiconductor device according to Embodiment 1.

FIG. 3 is a process chart showing a method for correcting a defect of an exposure mask (halftone mask) according to a second embodiment.

FIG. 4 is a schematic diagram showing an exposure method using an exposure mask, a method for manufacturing a semiconductor device, and a semiconductor device according to a second embodiment.

FIG. 5 is a process chart showing a defect correction method for an exposure mask (halftone type mask) according to a third embodiment.

FIG. 6 is a process chart showing a defect correction method for an exposure mask (upper shifter type Levenson type mask) according to a fourth embodiment.

FIG. 7 is a process chart showing another defect correction method of the exposure mask (upper shifter type Levenson type mask) of the fifth embodiment.

FIG. 8 is a process chart showing a defect correcting method of an exposure mask (lower shifter type Levenson type mask) according to a sixth embodiment.

FIG. 9 is a process chart showing another defect correction method of the exposure mask (lower shifter type Levenson type mask) of the sixth embodiment.

FIG. 10 is a process diagram showing still another defect correction method for the exposure mask (lower shifter type Levenson type mask) of the seventh embodiment.

FIG. 11 is a process diagram showing another defect correction method for an exposure mask (substrate engraving type Levenson-type mask) according to the eighth embodiment.

FIG. 12 is a process chart showing another defect correction method for an exposure mask (substrate engraving type Levenson-type mask) according to the ninth embodiment.

FIG. 13 is a process chart showing a defect correcting method for an exposure mask (a substrate engraving type Levenson-type mask) according to the tenth embodiment.

FIG. 14 is a process chart showing a defect correcting method for an exposure mask (a substrate engraving type Levenson-type mask) according to an eleventh embodiment.

FIG. 15 is a process chart showing a defect correcting method for an exposure mask (a substrate engraving type Levenson-type mask) according to a twelfth embodiment.

FIG. 16 is a process chart showing a defect correcting method of an exposure mask (a substrate engraving type Levenson-type mask) according to a thirteenth embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... board | substrate, 10A ... deterioration part, 10B ... substrate removal part, 11 ... light shielding layer, 12 ... semi-light shielding layer, 1
3, 14: transparent layer, 14B: transparent layer removing part, 1
5, 15B: groove, 16: resist mask, 2
0: black defect (processing residue of light shielding layer), 21: shifter defect (processing residue of semi-light shielding layer or transparent layer), 30: light transmitting area, 300: light transmitting area group, 31 ... light shielding area, 32, 34, 36 ... first light transmission area, 32
0, 340, 360 ... first light transmission area group, 33, 3
5, 37... Second light transmission area, 330, 350, 37
0: second light transmitting region group, 40: semiconductor substrate, 4
DESCRIPTION OF SYMBOLS 1 ... Insulating layer, 41A ... Opening part, 42 ... Metal layer, 42A ... Wiring layer, 43 ... Photoresist layer, 43A ... Resist mask, PM1, PM2 ...
.Exposure masks, S1, S2... Semiconductor devices

Claims (27)

[Claims] An exposure mask defect correcting method for correcting a defect of an exposure mask comprising a substrate transparent to exposure light and having a light transmitting area and a light shielding area formed on the substrate, (B) a step of removing a defect remaining in the light transmitting region; and (b) a step of etching the light transmitting region in which the defect remains to a predetermined depth. How to fix. In the step (a), defects are removed by using a focused ion beam, and in the step (b), a depth capable of removing a deteriorated portion generated in a light transmitting region due to irradiation of the focused ion beam. 2. The method according to claim 1, wherein etching is performed. 3. A first light transmission region group comprising a plurality of light transmission regions formed on a substrate, the first light transmission region group comprising a plurality of light transmission regions formed on the substrate, and another plurality of light transmission regions formed on the substrate. And a second light transmitting region group comprising: a first light transmitting region group, and a predetermined phase difference between the exposure light passing through the first light transmitting region group and the exposure light passing through the second light transmitting region group. A method for correcting a defect of an exposure mask for correcting a defect, comprising: (a) a step of removing a defect remaining in the light transmitting region; and (b) a light transmitting region group including the light transmitting region in which the defect remains. Etching the mask to a predetermined depth. In the step (a), defects are removed by using a focused ion beam, and in the step (b), a depth capable of removing a deteriorated portion generated in a light transmitting region due to irradiation of the focused ion beam. 4. The method according to claim 3, wherein the light transmitting region group is etched. 5. The method according to claim 3, wherein in the step (b), a predetermined phase difference is achieved by etching a light transmitting region group including the light transmitting region where the defect remains.
3. The method for correcting a defect of an exposure mask according to item 1. 6. In the step (b), the light transmitting region group including the light transmitting region where the defect remains and the light transmitting region group including the light transmitting region where the defect does not remain are etched. The method for correcting a defect of an exposure mask according to claim 5. 7. In the step (b), the light transmitting region group including the light transmitting region where the defect remains and the light transmitting region group including the light transmitting region where the defect does not remain are etched. After the step (b), (c) a step of achieving a predetermined phase difference by re-etching the light transmission region group including the light transmission region where the defect remains. Item 3. The method for correcting a defect of an exposure mask according to Item 3. 8. The method according to claim 8, further comprising: after the step (b), (c) etching the light transmitting region group including the light transmitting region where no defect remains to achieve a predetermined phase difference. 4. The method according to claim 3, wherein the exposure mask has a defect. 9. In the step (b), the light transmitting region group including the light transmitting region where the defect remains and the light transmitting region group including the light transmitting region where the defect does not remain are etched. The method for correcting a defect of an exposure mask according to claim 8. 10. A defect remains in both the light transmitting region included in the first light transmitting region and the light transmitting region included in the second light transmitting region group. Etching the group, and after the step (b), (c) re-etching any one of the light transmitting region groups to achieve a predetermined phase difference. 3. The method for correcting a defect of an exposure mask according to item 3. 11. The method according to claim 3, wherein the predetermined phase difference is 180 ° ± 10 °. 12. A light-transmitting region comprising a substrate transparent to exposure light, a light-transmitting region and a light-shielding region formed on the substrate, wherein defects remaining in the light-transmitting region are removed and defects remain. An exposure mask, wherein the light transmitting region is etched to a predetermined depth. 13. The apparatus according to claim 1, wherein the predetermined depth is a depth at which a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect can be removed.
3. The exposure mask according to 2. 14. A first light transmitting area group comprising a plurality of light transmitting areas formed on the substrate, the first light transmitting area group comprising a plurality of light transmitting areas formed on the substrate, and another plurality of light transmitting areas formed on the substrate. A predetermined phase difference is generated between the exposure light passing through the first light transmission region group and the exposure light passing through the second light transmission region group. An exposure mask, wherein a defect remaining in a region is removed, and a light transmitting region group including a light transmitting region in which the defect remains is etched to a predetermined depth. 15. The method according to claim 1, wherein the predetermined depth is a depth at which a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect can be removed.
5. The exposure mask according to 4. 16. An exposure method for irradiating an exposure mask with exposure light and transferring a pattern formed on the exposure mask to a photoresist layer on a substrate, wherein the exposure mask is transparent to the exposure light. Substrate
A light-transmitting region and a light-shielding region formed on the substrate are provided. Defects remaining in the light-transmitting region are removed, and the light-transmitting region where the defect remains is etched to a predetermined depth. Characteristic exposure method. 17. The apparatus according to claim 1, wherein the predetermined depth is a depth capable of removing a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect.
7. The exposure method according to 6. 18. An exposure method for irradiating an exposure mask with exposure light and transferring a pattern formed on the exposure mask to a photoresist layer on a substrate, wherein the exposure mask is transparent to the exposure light. Substrate
A first light transmission region group formed of a plurality of light transmission regions formed on the substrate, and a second light transmission region group formed of another plurality of light transmission regions formed on the substrate; A predetermined phase difference occurs between the exposure light that has passed through the transmission region group and the exposure light that has passed through the second light transmission region group, so that the defect remaining in the light transmission region is removed, and the defect remains. An exposure method, wherein a light transmission area group including the light transmission area is etched to a predetermined depth. 19. The apparatus according to claim 1, wherein the predetermined depth is a depth at which a deteriorated portion generated in a light transmitting region due to irradiation with a focused ion beam for removing a defect can be removed.
9. The exposure method according to 8. 20. An exposure mask is irradiated with exposure light, a pattern formed on the exposure mask is transferred to a photoresist layer on a substrate, and the photoresist layer is developed using a resist mask obtained by developing the photoresist layer. A semiconductor device obtained by performing a treatment on a substrate, wherein the exposure mask is formed of a substrate transparent to exposure light,
A light-transmitting region and a light-shielding region formed on the substrate are provided. Defects remaining in the light-transmitting region are removed, and the light-transmitting region where the defect remains is etched to a predetermined depth. Characteristic semiconductor device. 21. A method according to claim 2, wherein the predetermined depth is a depth at which a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect can be removed.
0. The semiconductor device according to 0. 22. An exposure mask is irradiated with exposure light, a pattern formed on the exposure mask is transferred to a photoresist layer on a substrate, and the photoresist layer is developed using a resist mask obtained by developing the photoresist layer. A semiconductor device obtained by performing a treatment on a substrate, wherein the exposure mask is formed of a substrate transparent to exposure light,
A first light transmission region group formed of a plurality of light transmission regions formed on the substrate, and a second light transmission region group formed of another plurality of light transmission regions formed on the substrate; A predetermined phase difference occurs between the exposure light that has passed through the transmission region group and the exposure light that has passed through the second light transmission region group, so that the defect remaining in the light transmission region is removed, and the defect remains. A semiconductor device, wherein a light transmitting region group including the light transmitting region is etched to a predetermined depth. 23. The method according to claim 2, wherein the predetermined depth is a depth at which a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect can be removed.
3. The semiconductor device according to 2. 24. An exposure mask is irradiated with exposure light, a pattern formed on the exposure mask is transferred to a photoresist layer on a substrate, and the photoresist layer is developed using a resist mask obtained by developing the photoresist layer. A method of manufacturing a semiconductor device including a step of performing a treatment on a substrate, wherein the exposure mask comprises a substrate transparent to exposure light,
A light-transmitting region and a light-shielding region formed on the substrate are provided. Defects remaining in the light-transmitting region are removed, and the light-transmitting region where the defect remains is etched to a predetermined depth. A method for manufacturing a semiconductor device. 25. The apparatus according to claim 2, wherein the predetermined depth is a depth at which a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect can be removed.
5. The method for manufacturing a semiconductor device according to item 4. 26. An exposure mask is irradiated with exposure light, a pattern formed on the exposure mask is transferred to a photoresist layer on a substrate, and the photoresist layer is developed using a resist mask obtained by developing the photoresist layer. A method of manufacturing a semiconductor device including a step of performing a treatment on a substrate, wherein the exposure mask comprises a substrate transparent to exposure light,
A first light transmission region group formed of a plurality of light transmission regions formed on the substrate, and a second light transmission region group formed of another plurality of light transmission regions formed on the substrate; A predetermined phase difference occurs between the exposure light that has passed through the transmission region group and the exposure light that has passed through the second light transmission region group, so that the defect remaining in the light transmission region is removed, and the defect remains. A method of manufacturing a semiconductor device, wherein a group of light transmitting regions including a light transmitting region is etched to a predetermined depth. 27. A method according to claim 2, wherein the predetermined depth is a depth capable of removing a deteriorated portion generated in a light transmitting region due to irradiation of a focused ion beam for removing a defect.
7. The method for manufacturing a semiconductor device according to item 6.