KR101652339B1 - Patterning method using mold treated by self assembled monolayer - Google Patents

Abstract

The present invention relates to a method of pattern formation using a mold treated by a self-assembled monolayer, comprising: applying a photoresist to a substrate; Forming a self-assembled monolayer on the patterned mold; Pressing the mold with the self-assembled monolayer and the substrate coated with the photoresist; And curing the photoresist.

Description

TECHNICAL FIELD [0001] The present invention relates to a pattern forming method using a self-assembled monolayer,

The present invention relates to a pattern forming method using a mold treated by a self-assembled monolayer.

Generally, the key to semiconductor pattern transfer technology is to form a pattern using photolithography technology. The accuracy of the pattern formed by the photolithography technique is determined according to the wavelength of light used. Therefore, although visible light (visible light) was used initially, ultraviolet light was soon used, and recently, a fine pattern of about 1 μm or less is handled using an electron beam if necessary.

However, in the photolithography technique, as the circuits are miniaturized, the initial investment cost of the exposure equipment is increased, and the cost of the mask having a resolution similar to the wavelength of the light used is increased.

Accordingly, an imprinting method for forming a fine pattern using a mold has attracted attention as an alternative to high-cost photographic developing technology. The imprinting method is a technique for forming an organic layer pattern on a substrate, and it is possible to realize a fine pattern of about 100 nm or less, a process is quick and simple, and an easy-to-large-area technique.

Such techniques are divided into ultraviolet and thermal methods depending on the curing method of the polymer material. In the thermal imprinting process, the stamp is pressed onto the organic layer at a relatively high pressure in a state where the temperature is increased to be higher than the glass transition temperature, and then the temperature is lowered to the glass transition temperature to cure the organic layer to maintain the shape . The ultraviolet imprinting process is a method of curing a patterned organic layer by forming a network between molecules by exposing ultraviolet rays while the stamp and the organic layer are pressed using a transparent stamp. Korean Patent No. 10-0843342 relates to a process and apparatus for performing a UV nanoimprinting lithography. The uniform pressure application method reduces the defects due to air trap, and uniform pattern transfer property to a large area. RTI ID = 0.0 > imprinting < / RTI > However, since the imprinting method requires an oxygen plasma ashing process for the polymer residual layer between the pattern and the pattern, the height of the pattern is reduced in the process of removing the residual layer, and the damage of the pattern edge and the pattern shape change There is a problem that it can be induced.

In order to solve such a problem, development of a method for preventing the formation of a residual layer in a non-pattern forming portion of a photoresist layer in an imprinting process for forming a pattern is required.

The present application intends to provide a pattern forming method for preventing the formation of a residual layer in a non-pattern forming portion of a photoresist layer in an imprinting process for pattern formation.

According to a first aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: applying a photoresist to a substrate; Forming a self-assembled monolayer on the patterned mold; Pressing the mold with the self-assembled monolayer and the substrate coated with the photoresist; And a step of curing the photoresist.

According to one embodiment of the present disclosure, the substrate may be selected from the group consisting of silicon wafers, glass, ceramics, glass-ceramics, metals, metal oxides, polymers, and combinations thereof, .

According to one embodiment of the present invention, the photoresist may include, but is not limited to, a positive photoresist or a negative photoresist.

According to one embodiment of the present invention, the photoresist may include, but is not limited to, curing by heating or ultraviolet irradiation.

According to one embodiment of the present application, the step of applying the photoresist may be performed by a method selected from the group consisting of spin coating, dipping coating, roll to roll coating, flow coating, and spray coating, .

According to one embodiment of the present invention, the contact may be, but not limited to, simultaneous photoresist imprinting and self-assembled monolayer and surface-to-substrate micro contact printing.

According to one embodiment of the invention, the volume of the photoresist applied to the substrate may be less than the volume of the recessed portion of the pattern formed in the mold, but may not be limited thereto.

According to one embodiment of the present invention, the mold may include, but is not limited to, a polymer mold or a mold coated with a flexible polymer material on a rigid substrate.

According to one embodiment of the present invention, the polymer mold may include, but is not limited to, selected from the group consisting of polydimethylsiloxane, polyurethane, polyimide, and combinations thereof.

According to one embodiment of the invention, the pattern of the mold may include, but is not limited to, selected from the group consisting of polygonal, hemispherical, and combinations thereof.

According to one embodiment of the invention, the mold may additionally include, but is not limited to, a surface treatment to increase the strength of the surface.

According to one embodiment of the disclosure, the mold may additionally include, but is not limited to, a surface treatment to increase wettability before forming the self-assembled monolayer on its surface.

According to one embodiment of the present invention, the surface treatment may be performed by ultraviolet irradiation or an atmospheric plasma treatment, but the present invention is not limited thereto.

According to one embodiment of the present invention, the step of forming the self-assembled monolayer may be performed by a method selected from the group consisting of dipping coating, spin coating, roll-to-roll coating or vapor deposition, have.

According to one embodiment of the present invention, the self-assembled monolayer may have a terminal end opposite to that of the photoresist applied to the substrate, but may not be limited thereto.

According to an embodiment of the present invention, the self-assembled monolayer may include APS [(3-aminopropyl) trimethoxysilane], MUA (11-mercaptoundecanoic acid), DET [(3-trimethoxysilylpropyl) diethylenetriamine] 3-aminopropyltrimethoxysilane), PTS (perfluorodecyltrichlorosilane), OTS (octadecyltrichlorosilane), OTMS (octadecyltrimethoxysilane), HDT (1-hexadecanethiol), FDTS [(heptadecafluoro-1,1,2,2 -tetrahydrodecyl) trichlorosilane], FOTS 1H, 2H, 2H-perfluorodecyltrichlorosilane-perfluorodecyltrichlorosilane, PFBT, dichloromethylsilane (DDMS), and combinations thereof.

According to the present invention, by forming a pattern using the imprinting method, the process can be simplified and the patterning time can be shortened as compared with the conventional photolithography process. By using the self-assembled monolayer processed mold , An adhesion preventive film between the mold and the photoresist is formed to form a pattern more clearly and the lifetime of the mold can be extended. Further, by preventing the formation of the residual layer in the non-patterned portion of the photoresist layer, the etching or the ashing process, which was essentially involved in the existing pattern formation method, is not performed, Minimizing damage, and simplifying the process.

FIGS. 1A and 1B are diagrams showing a process of obtaining a mold having a self-assembled monolayer according to an embodiment of the present invention.
FIGS. 2A to 2D are diagrams illustrating a pattern formation method using a mold processed by a self-assembled monolayer according to an embodiment of the present invention.
3A is a cross-sectional scanning electron micrograph of a substrate on which a photoresist pattern formed using a conventional mold is formed, and FIG. 3B is a cross-sectional scanning electron micrograph of a substrate using a self-assembled monomolecular film-treated mold according to an embodiment of the present invention Sectional scanning electron microscope (SEM) photograph of a substrate on which pattern formation of a photoresist is completed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It should be understood, however, that the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, the same reference numbers are used throughout the specification to refer to the same or like parts.

Throughout this specification, when a part is referred to as being "connected" to another part, it is not limited to a case where it is "directly connected" but also includes the case where it is "electrically connected" do.

Throughout this specification, when a member is " on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as "including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms "about "," substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) "or" step "used to the extent that it is used throughout the specification does not mean" step for.

Throughout this specification, the term " combination thereof " included in the expression of the machine form means one or more combinations or combinations selected from the group consisting of the constituents described in the expression of the machine form, And the like.

Hereinafter, a pattern forming method using the self-assembled monomolecular film-treated mold of the present invention will be described in detail with reference to the accompanying drawings.

FIGS. 1A and 1B are diagrams showing a process of obtaining a mold having a self-assembled monolayer according to an embodiment of the present invention.

As shown in Fig. 1A, a patterned mold 120 is prepared.

The pattern portion of the mold 120 may include, but is not limited to, a polygonal, hemispherical, and combinations thereof. For example, the pattern portion of the mold may be hemispherical in the convex shape of the convex portion of the mold. For example, the pattern portion of the mold may be a trapezoidal polygonal shape having a narrow edge portion of the mold. For example, if the embossed portion of the mold has a wider trapezoidal shape at the end portion, the embossed portion of the mold may be torn when the mold is separated from the substrate, but may not be limited thereto.

The patterned mold 120 may include, but is not limited to, a polymer mold or a mold coated with a rigid substrate using a flexible polymer material. As a method of forming a pattern on the mold 120, for example, a photoresist is applied to a substrate, and then a pattern is formed by a photolithography method. Next, the patterned substrate may be prepared by applying a polymer mixture to the patterned substrate, followed by curing, but the present invention is not limited thereto. The polymer blend according to one embodiment of the present invention may be manufactured by stirring Silgur A and Silgur B at a ratio of about 10: 1, but the present invention is not limited thereto.

The polymer mold 120 may include, but is not limited to, selected from the group consisting of polydimethylsiloxane (PDMS), polyurethane, polyimide, and combinations thereof. have. For example, the polymer mold may use a PDMS mold, but the present invention is not limited thereto. The PDMS can be stably adhered to a wide area of the substrate, uniformly applied to a non-planar surface, and durable, so that it can be used for a long time in the production of a mold and its surface tension is low. When the polymer is molded, adhesion is not generated well, and thus good molding processability is obtained.

Then, the patterned mold 120 may further include a surface treatment for increasing the strength of the surface, but may not be limited thereto. The surface treatment may be performed, for example, by a MINs coating of a polyurethane series, but may not be limited thereto. Since the surface of the PDMS is hydrophobic, it is difficult to align the self-assembled monolayer having hydrophilicity on the surface. Therefore, the types of the self-assembled monolayer membranes that can be used are limited. The types of self-assembled monolayer membranes aligned by surface modification using materials such as MINs can be variously changed. In addition, since the PDMS has a very high ductility, the pattern must be physically pressed during the imprinting process, so that the pattern may be easily damaged. Therefore, by coating the portion of the mold where the contact with the photoresist occurs using MINs, the strength of the mold can be increased and the life of the mold can be extended. The coating of the MINs may be performed, for example, by spin coating, but is not limited thereto.

May further include a surface treatment to increase the wettability of the self-assembled monolayer 130 prior to forming the self-assembled monolayer 130 in the mold 120 with improved surface strength characteristics, . The surface treatment may be performed by ultraviolet irradiation or an atmospheric plasma treatment, but the present invention is not limited thereto. When the surface treatment is performed, OH-groups are formed on the surface of the mold 120 to hydrophilize the surface, thereby increasing the adsorption amount of the self-assembled monolayer 130.

Subsequently, a self-assembled monolayer 130 is formed on the mold 120, as shown in FIG. 1B. A self-assembled monolayer (SAM) is a regularly aligned organic molecule spontaneously deposited on the surface of a given substrate and consists of three parts. First, it is divided into a reactor of the head part which binds to the substrate, a long alkalic chain of the body part which enables regular molecular film formation, and a functional part of the tail part which controls the function of the molecular membrane. Self-assembled monolayer films often have direct chemical bonds between the surface of the substrate and the molecules forming the membrane, which can form a very robust film. In addition, it is not affected by the shape and size of the substrate, and thus it is possible to manufacture the substrate even on complicated shaped substrates, and it is easy to maximize the size.

The self-assembled monolayer 130 may have a terminal end opposite to the photoresist applied to the substrate, but may not be limited thereto. For example, when the photoresist exhibits hydrophilicity, the self-assembled monolayer has a hydrophobic end group, and when the photoresist exhibits hydrophobicity, the self-assembled monolayer has a hydrophilic end group. The self-assembled monolayer having the hydrophilic end group may be selected from the group consisting of APS [(3-aminopropyl) trimethoxysilane], MUA (11-mercaptoundecanoic acid), DET [(3-trimethoxysilylpropyl) diethylenetriamine] -aminoethyl) -3-aminopropyl trimethoxysilane, and combinations thereof. The self-assembled monolayer 130 having the hydrophobic end group may be formed of a perfluorodecyltrichlorosilane (PFS), an octadecyltrichlorosilane (OTS), an octadecyltrimethoxysilane (OTMS), a 1-hexadecanethiol (HDTS), a heptadecafluoro-1,1,2 2, -tetrahydrodecyl) trichlorosilane], FOTS (1H, 1H, 2H, 2H-perfluorodecyltrichlorosilane-perfluorodecyltrichlorosilane), PFBT (pentafluorobenzenethiol), DDMS (dichlorodimethylsilane), and combinations thereof , But may not be limited thereto.

The method for forming the self-assembled monolayer 130 may be performed by a method selected from the group consisting of dipping coating, spin coating, roll-to-roll coating, and vapor deposition. According to one embodiment of the present application, about 1 mL of a perfluorodecyltrichlorosilane (PFS) self-assembled monolayer is diluted in about 50 mL of a hexane solution to form a self-assembled monolayer solution. When the self-assembled monolayer 130 is formed by a spin coating method, for example, the self-assembled monolayer solution is dropped on the patterned mold and then spin-coated at about 3,000 rpm for about 30 seconds, The self-assembled monolayer may be formed to have a predetermined thickness on the substrate. However, the present invention is not limited thereto. When the self-assembling monolayer 130 is formed by a vapor deposition method, for example, a mold is placed in a vacuum oven preheated to about 150 ° C., and the self-assembled monolayer solution is introduced into a vacuum oven while the vacuum is maintained. And the vacuum oven is made into a PFS self-assembled monolayer atmosphere. The self-assembled monolayer 130 may be formed on the mold 120 by applying the self-assembled monolayer 130 sufficiently to the mold, lowering the temperature to room temperature, and forming a normal pressure state. However, .

FIGS. 2A to 2D are diagrams illustrating a pattern formation method using a mold processed by a self-assembled monolayer according to an embodiment of the present invention.

As shown in FIG. 2A, a substrate 100 to which a photoresist 110 is applied is prepared.

The substrate 100 may include, but is not limited to, selected from the group consisting of silicon wafers, glass, ceramics, glass-ceramics, metals, metal oxides, polymers, and combinations thereof. First, the substrate 100 is prepared by washing according to a conventional method. Cleaning the substrate 100 in this manner is for removing organic matter present on the substrate 100. When the organic material is present on the substrate 100, there is a problem that the photoresist 110 can not be uniformly applied during the subsequent application of the photoresist 110. After immersing the base material 100 in the detergent for a predetermined period of time, the base material 100 is rinsed to remove the organic material. For example, the substrate may be cleaned using, but not limited to, piranha solution. The piranha solution may be prepared by mixing sulfuric acid (H ₂ SO ₄ ) and hydrogen peroxide (H ₂ O ₂ ) at a ratio of about 4: 1, but is not limited thereto. In the step of rinsing the substrate, rinsing may be performed using deionized water to prevent re-contamination of the substrate, but the present invention is not limited thereto.

A photoresist (hereinafter also referred to as 'PR') 110 is applied to the cleaned substrate 100. For example, the PR 110 may include, but is not limited to, a positive PR or a negative PR. The step of applying the PR 110 may be performed by, for example, a method selected from the group consisting of spin coating, dipping coating, roll to roll coating, flow coating, and spray coating, . When the spin coating method is used instead of the spray coating in the application of the PR 110, the PR 110 can be more uniformly coated on the substrate 100.

Subsequently, as shown in FIG. 2B, the self-assembled monolayer 130 is contacted with the coated mold 120 and the substrate 100 to which the PR 110 is applied.

When the mold 120 in which the self-assembling monolayer 130 is formed is brought into contact with the substrate 100 to which the PR 110 is applied, the contact is performed by PR (110) imprinting, But the present invention is not limited thereto. The reason why the imprinting method and the micro contact printing method are simultaneously performed when the mold 120 and the substrate 100 are in contact with each other is that when the PR imprinting process is performed only, There is a further need for a remaining PR film removal process in the pattern. In addition, when PR curing is performed, there is a problem that the shape can not be maintained due to the flowability of the PR, and a problem of flowing down may occur, and the exposed portion of the substrate may be narrowed so that a desired shape can not be obtained. For example, when PR is applied after performing only the micro-contact printing method between the self-assembled monolayer film and the substrate, the PR can not be aligned on the substrate over a predetermined height. Due to the low height, A problem may occur in which all are etched. In order to solve such a problem, in one embodiment of the present invention, the imprinting method of the PR and the surface fine contact printing method of the self-assembled monolayer can be simultaneously performed, The pattern is formed in a predetermined shape.

The volume of the PR 110 applied to the substrate 100 may be less than the volume of the recessed portion of the pattern formed on the mold 120, but may not be limited thereto. 2C, when the volume of the PR 110 is smaller than the volume of the depressed portion of the pattern formed on the mold 120, when the substrate 100 and the mold 120 are in contact with each other, The mold 110 may be changed into a shape that is formed in the recessed portion of the pattern formed on the mold 120 in a uniformly coated form on the substrate 100. In order to form the PR 110 in the recessed portion of the pattern formed on the mold 120, the mold 120 may be formed in a special shape that widens the recessed portion of the pattern formed on the mold 120 But may not be limited thereto. The PR may include, but is not limited to, curing by heating or ultraviolet irradiation. When the PR is cured by heating for a predetermined time, a pattern is formed as shown in FIG. 2D, and no PR is left in the non-patterned region on the substrate 100, so that a separate etching process is not required.

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited thereto.

< Example >

PDMS in a liquid state in which sylgard A and yarn guard B were mixed at a ratio of 10: 1 was applied on the pattern mask, and then cured in an oven at 80 ° C for 1 hour. When the PDMS is cured and becomes a flexible solid state, the mold is separated from the mask.

The self-assembled monolayer solution was prepared by diluting 1 mL of perfluorodecyltrichlorosilane (PFS) self-assembled monolayer in 50 mL of hexane solution for self-assembled monolayer treatment. When the self-assembled monolayer film was formed through a spin coating method, the self-assembled monolayer film was dropped and then spin-coated at 3,000 rpm for 30 seconds to form the self-assembled monolayer film with a predetermined thickness on the mold. When the self-assembled monolayer film was formed by the vapor deposition method, the mold was placed in a vacuum oven preheated to 150 ° C, and then the self-assembled monolayer solution was injected into the vacuum oven while the vacuum was maintained, Assembled monolayer atmosphere. After one hour, the self-assembled monolayer was sufficiently applied to the mold, the temperature was lowered to room temperature, and the self-assembled monolayer was formed in the mold.

On the other hand, a Si substrate was used as a lower substrate, and the substrate was dipped in a piranha solution (H ₂ SO ₄ : H ₂ O ₂ = 4: 1) for 10 minutes to prepare the substrate. On the cleaned substrate, AZ1512, a positive PR of AZ electronic materials, was applied by spin coating at 2,000 rpm for 60 seconds as a PR.

 The PR base coated Si substrate and the self-assembled monolayer treated mold were brought into contact with each other. The contact was cured at 80 DEG C for 2 minutes by heating. At this time, when negative PR is used, it can be further cured by exposure to ultraviolet rays.

The substrate and the mold were separated to form a pattern.

3A is a scanning electron microscope (SEM) image of a cross-section of a substrate formed with a PR pattern formed using a conventional general mold, FIG. 3B is a cross-sectional view of a PR transfer process using a self-assembled monolayer- Is a scanning electron microscope (SEM) image of a cross-section of a substrate having a PR pattern formed thereon.

As shown in FIG. 3A, in the conventional pattern forming method using a general mold, a PR of 200 nm is left on the base of the patterned portion by imprinting. However, as shown in FIG. 3B, It was confirmed that when the PR imprinting method and the micro-contact printing between the self-assembled monolayer film and the substrate surface were simultaneously performed using the monomolecular film-processed mold, the substrate surface was exposed without the residual layer of PR.

This makes it possible to simplify the pattern formation process by not performing additional etching or an ashing process due to the residual PR formed on the substrate.

It will be understood by those of ordinary skill in the art that the foregoing description of the embodiments is for illustrative purposes and that those skilled in the art can easily modify the invention without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

100: substrate
110: photoresist
120: mold
130: self-assembled monolayer

Claims (16)

Applying a photoresist to the substrate;
Forming a self-assembled monolayer on the patterned mold;
Pressing the mold with the self-assembled monolayer and the substrate coated with the photoresist; And
And curing the photoresist,
The contact is caused by a photoresist imprinting method, a surface micro-contact printing method between the self-assembled monolayer and the substrate,
The volume of the photoresist applied to the substrate is less than the volume of the recessed portion of the pattern formed in the mold,
Further comprising the step of performing a surface treatment to increase the strength of the surface before forming the self-assembled monolayer in the patterned mold.
Pattern formation method.
The method according to claim 1,
Wherein the substrate comprises a material selected from the group consisting of silicon wafers, glass, ceramics, glass-ceramics, metals, metal oxides, polymers, and combinations thereof.
The method according to claim 1,
Wherein the photoresist comprises a positive photoresist or a negative photoresist.

The method according to claim 1,
Wherein the photoresist is cured by heating or ultraviolet radiation.
The method according to claim 1,
Wherein the step of applying the photoresist is carried out by a method selected from the group consisting of spin coating, dipping coating, roll to roll coating, flow coating, or spray coating.
delete delete The method according to claim 1,
Wherein the mold comprises a polymer mold or a mold coated with a rigid base material using a flexible polymeric material.
9. The method of claim 8,
Wherein the polymeric mold comprises a material selected from the group consisting of polydimethylsiloxane, polyurethane, polyimide, and combinations thereof.
The method according to claim 1,
Wherein the pattern of the mold comprises a cross-section selected from the group consisting of polygonal, hemispherical, and combinations thereof.
delete The method according to claim 1,
Performing a surface treatment to increase the strength of the surface of the patterned mold before the step of forming the self-assembled monolayer, and then performing a surface treatment for increasing wettability Gt;
13. The method of claim 12,
Wherein the surface treatment for increasing the wettability is performed by ultraviolet irradiation or atmospheric plasma treatment.
The method according to claim 1,
Wherein the step of forming the self-assembled monolayer is performed by a method selected from the group consisting of dipping coating, spin coating, roll-to-roll coating, or vapor deposition.
The method according to claim 1,
Wherein the self-assembled monolayer is a self-assembled monolayer having a hydrophobic end group when the photoresist is a hydrophilic photoresist and the self-assembled monolayer having a hydrophilic end group when the photoresist is a hydrophobic photoresist, Way.
16. The method of claim 15,
The self-assembled monolayer having the hydrophilic end group may be selected from the group consisting of APS [(3-aminopropyl) trimethoxysilane], MUA (11-mercaptoundecanoic acid), DET [(3-trimethoxysilylpropyl) diethylenetriamine] -aminopropyl trimethoxysilane, and combinations thereof. The self-assembled monolayer having the hydrophobic end group may be at least one selected from the group consisting of PFS (perfluorodecyltrichlorosilane), OTS (octadecyltrichlorosilane), OTMS (octadecyltrimethoxysilane), HDT -hexadecanethiol, FDTS [heptadecafluoro-1,1,2,2 -tetrahydrodecyl) trichlorosilane], FOTS (1H, 1H, 2H, 2H- perfluorodecyltrichlorosilane-perfluorodecyltrichlorosilane), PFBT (pentafluorobenzenethiol) &Lt; / RTI &gt; and combinations thereof.

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