JP2000228398A - Processing apparatus, method for preventing adhesion of attached matter using the same, method for manufacturing semiconductor device, components of semiconductor manufacturing apparatus, and focus ring - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To suppress the adhesion layer of a reaction product and the coating on the device surface from peeling off, reduce particles in a chamber, and maintain the yield of a product, for example, a semiconductor device, or A processing apparatus for mainly manufacturing a semiconductor device, a method for preventing separation of a deposit using the same, a method for manufacturing a semiconductor device, a component of the semiconductor manufacturing apparatus, and a focus ring capable of improving the operation rate of the apparatus while improving the operation rate I will provide a. In one embodiment, at least a part of a component in a processing tank of a processing apparatus that performs processing for manufacturing a semiconductor device on an object mounted in the processing tank is divided by a substantially vertical step. The above-mentioned problem is solved by having a surface composed of the small regions described above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus for performing a process for manufacturing a semiconductor device, which is used in a manufacturing process of a semiconductor integrated circuit or the like, a method for preventing separation of attached matter using the same, and a method for manufacturing a semiconductor device. And a component and a focus ring of a semiconductor manufacturing apparatus. In particular, the present invention relates to a processing apparatus suitable for a plasma processing apparatus such as a dry etching apparatus and a CVD apparatus, a method for preventing adhered substances from being stripped, a method for manufacturing a semiconductor device, a component of the semiconductor manufacturing apparatus, and a focus ring.

[0002]

2. Description of the Related Art Many dry etching techniques, CVD techniques, and the like are applied to semiconductor device manufacturing techniques.
In these techniques, gas is processed by plasma decomposition or thermal decomposition to process a wafer or form a film on the wafer. For this reason, it is inevitable that a part of the reaction product remains, adheres, and accumulates in the chamber irrespective of various application methods. When the amount of the attached matter increases, particles due to the attached matter increase in the chamber, and the particles are injected into a reaction system such as plasma and re-decomposed, so that desired processing characteristics and film forming properties are obtained. No longer available. In addition, peeling off of the deposits may cause apparent defects in processing and film formation.

In order to cope with such a problem, it is necessary for the processing apparatus to always perform mechanical cleaning at a constant frequency. However, mechanical cleaning requires time to work, such as the need to adjust the temperature of the chamber to open to the atmosphere, and sufficient removal of atmospheric components when restarting, and significantly reduces the equipment operation rate. Let it. Therefore, a method for reducing the frequency of mechanical cleaning has been devised.

For example, particles can be reduced by volatilizing and removing attached matter by dry cleaning using various reactive gases. Alternatively, Japanese Patent Application Laid-Open No.
As in the technology disclosed in Japanese Patent No. 3180 and US Pat. No. 5,474,649, the surface of a component inside the chamber is roughened by frost treatment (also called bead blast) to increase the adhesion of the adhered substance. There is a way. U.S. Pat. No. 5,474,649 discloses a method of forming a pattern on a component by engraving, etching, or molding, in addition to bead blasting.

[0005] A processing apparatus applied to the dry etching technique and the CVD technique may use a material obtained by subjecting a base material to a surface treatment and forming a coating layer as a material of components in the chamber including the chamber itself. Many. However, when a treatment apparatus using such a surface treatment material is repeatedly used, the material deterioration of the surface treatment material causes
The coating may fall off. Again,
The same problem as the above-mentioned detachment of the deposit occurs.

As a method for dealing with such a problem, a method of replacing the deteriorated material itself has been proposed. As a processing apparatus for performing this method, the inner wall surface of the processing apparatus has a two-layer structure, and the deterioration is performed. There is proposed a processing device or the like in which a portion in which the occurrence of the phenomenon occurs is detachably arranged.

[0007]

As a countermeasure for particles caused by deposits of reaction products, the above-described method for reducing particles caused by deposits by dry cleaning uses gas excitation by plasma. There are many. In this case, although the cleaning effect is large in a region where plasma can be irradiated, there is a problem that the attached matter cannot be completely removed in a region where plasma cannot be irradiated. In particular, it is hardly effective for a processing apparatus of a type in which plasma is confined in a part of a chamber, such as a parallel plate structure having a narrow gap. Further, even with a conventional method in which gas excitation or reaction is performed by a method other than plasma, a cleaning effect cannot be effectively exerted on the entire inside of the chamber.

[0008] The method of performing frost treatment on the constituent material in the chamber to increase the adhesion of the deposit is effective when the deposit is relatively thin or the internal stress of the deposit is relatively small. is there. However, when the thickness of the attached matter is several tens μm or several hundred μm or more, there is a problem that it is difficult to suppress the detachment of the attached matter with an adhesion force obtained by the frost treatment.

[0009] Regarding the problem that the coated part of the material of the component parts comes off, even if the inner wall surface has a two-layer structure and the deteriorated part can be attached and detached, it is necessary to perform the replacement work at regular intervals. The frequency of opening cannot be reduced. Therefore, there is a problem that the operation rate of the apparatus cannot be improved. Further, for example, when it is necessary to clean the deposits on the surface treatment material by brushing or the like, it is inevitable that the consumption of the coating portion is further accelerated, thereby increasing the running cost of the apparatus.

[0010] In view of the above problems, the present invention suppresses the adhesion layer of the reaction product and the coating on the device surface from peeling off, reduces particles in the chamber, and
For example, while maintaining or improving the yield of semiconductor devices and the like, it is possible to improve the operation rate of the devices, mainly a processing device for manufacturing semiconductor devices, a method for preventing the separation of deposits using the same, and a semiconductor device. It is an object of the present invention to provide a manufacturing method, a component of a semiconductor manufacturing apparatus, and a focus ring.

[0011]

In order to achieve the above object, the present invention provides the following processing apparatus. That is, the present invention is a processing apparatus for performing a process for manufacturing a semiconductor device on an object to be processed mounted in a processing tank, wherein at least some of the components in the processing tank are substantially vertical. An object of the present invention is to provide a processing apparatus having a surface including a plurality of small areas divided by a step.

Here, it is preferable that the plurality of small regions are arranged according to a temperature gradient formed on a surface of the component during operation of the processing apparatus. Further, the present invention can be suitably applied to the case where deposits are deposited on the surface composed of the plurality of small regions by operation of the apparatus. At this time, it is preferable that the step has a height sufficient to prevent the detachment of the deposit, and the plurality of small areas restrict the size of the deposit to remove the deposit. It is preferable to have an appropriate area in order to prevent the above. Preferably, the object to be processed is a wafer, and the processing tank is a tank for performing a dry etching process on a silicon oxide film on the surface of the wafer using a fluorine-based gas. Further, it is preferable that the surface is an aluminum surface having an alumite treatment layer. The plurality of small regions are preferably substantially flat, and the plurality of small regions are preferably arranged in a regular pattern.

Further, the present invention is directed to a processing apparatus for performing processing for manufacturing a semiconductor device, wherein when processing an object to be processed mounted in the processing tank, the components of the processing tank are processed by the processing apparatus. A processing apparatus is used in which at least a part of a surface on which deposits are deposited by operation is divided into small areas by substantially vertical steps having a height sufficient to prevent the detachment of the deposits. An object of the present invention is to provide a method for preventing kimono peeling.

Further, according to the present invention, when a semiconductor device substrate mounted in a processing bath is processed in order to manufacture a semiconductor device, the surface of the component in the processing bath on which deposits are deposited by the processing is deposited. It is an object of the present invention to provide a method of manufacturing a semiconductor device, characterized in that at least a part of the film is divided into a plurality of small regions by a step for limiting the size by dividing the film of the attached matter. Here, the plurality of small regions have a plurality of convex small regions and concave small regions divided by the step, and adjacent convex small regions are separated by a distance that divides the film of the attached matter. Is preferred. It is preferable that the step has an angle at which the film of the deposit is divided. It is preferable that the step has a height that divides the film of the deposit. Further, the step divides the adhesion film deposited during a required cumulative processing time,
It is preferable to prevent peeling.

Further, according to the present invention, when a semiconductor device substrate mounted in a processing bath is processed to manufacture a semiconductor device, the surface of the component in the processing bath on which deposits are deposited by the processing is deposited. It is an object of the present invention to provide a method of manufacturing a semiconductor device, wherein at least a part is divided into a plurality of small regions by a substantially vertical step. Furthermore, in order to manufacture a semiconductor device, at the time of processing a semiconductor device substrate mounted in a processing bath, at least a part of a surface of a component in the processing bath on which deposits are deposited by the processing is one-dimensionally processed. The present invention provides a method for manufacturing a semiconductor device, characterized in that a plurality of small convex regions are divided by a specific groove. Here, it is preferable that the deposition of the deposit occurs in a ring-shaped region on the surface of the component, and the groove is disposed substantially perpendicular to a circumferential direction of the ring-shaped region. Further, the component has an inner edge surrounding the semiconductor device substrate mounted in the processing bath, and the groove has
Preferably, it is arranged near the inner edge and substantially perpendicular to the inner edge. Preferably, the groove is arranged substantially along a temperature gradient formed on the surface of the component during operation of the apparatus.

According to the present invention, there is provided a component in a processing tank for mounting a semiconductor device substrate for manufacturing a semiconductor device, wherein at least a part of the surface has a plurality of substantially vertical steps. The present invention provides a component of a semiconductor manufacturing apparatus characterized by being divided into small areas. The present invention also provides a plasma processing apparatus for manufacturing a semiconductor device, a focus ring surrounding a semiconductor device substrate to be processed, a surface near the inner edge thereof, a plurality of arranged substantially perpendicular to the inner edge. Characterized by having an area divided into a plurality of convex small areas by the groove,
A focus ring is provided.

According to the present invention, there is provided a processing apparatus for performing processing for manufacturing a semiconductor device, comprising:
A surface formed of a plurality of small regions divided by a step, for example, a portion divided into a concave portion or a convex portion separated by a step is provided at a location where the reaction product is attached. Thereby, even if the adhesion film of the reaction product in the treatment tank of the treatment apparatus becomes thick, it is possible to suppress the detachment of the adhesion layer. Therefore, the operation rate of the device can be improved.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A processing apparatus according to the present invention, a method for preventing the detachment of attached matter using the same, a method for manufacturing a semiconductor device, and components and a focus ring of the semiconductor manufacturing apparatus based on a preferred embodiment shown in the accompanying drawings. This will be described in detail below. FIG. 1 is a schematic cross-sectional view showing a schematic configuration of an embodiment of a plasma processing apparatus that performs a dry etching process using the processing apparatus according to the present invention.

As shown in FIG.
Is a dry etching apparatus for manufacturing a semiconductor device, in which an oxide film such as a silicon oxide film is etched by high frequency (RF) plasma, and has a parallel plate structure with a narrow gap. Various constituent parts are provided in a processing tank (chamber) 12 in which a workpiece (semiconductor wafer) is mounted. An upper electrode 14 connected to a gas inlet 13 through which an etching gas can be introduced is installed at the upper center of the chamber 12. At the lower center of the chamber 12, a lower electrode 16 having an electrostatic chuck 17 for fixing a wafer 26 to be dry-etched is provided. Upper electrode 1
An upper quartz jig 18 is provided around the periphery of the lower electrode 16 so as to cover it, and a lower quartz jig 2 is provided around the lower electrode 16 so as to cover the lower electrode 16.
0 is placed. Further, outside the chamber 12, an RF power splitter 22 for applying a high frequency power (RF power) to both the upper electrode 14 and the lower electrode 16;
An RF power supply 24 connected to the power splitter 22 is provided. As a result, RF plasma is generated in the chamber 12, and dry etching is performed. Here, in the illustrated plasma processing apparatus 10, at least one of the upper quartz jig 18 and the lower quartz jig 20 has a surface formed of a plurality of small regions divided by a step, which is a feature of the present invention, for example, A portion (see FIG. 2) divided into a concave portion or a convex portion separated by a substantially vertical step is provided near the upper and lower electrodes 14 and 16.

Here, the chamber 12 of the plasma processing apparatus 10 can be evacuated to a predetermined degree of vacuum, for example, about 10 −6 Torr. The lower electrode 1
The fixing method of the wafer 26 on 6 is not particularly limited,
Any method may be used. For example, a mechanical clamp method may be used. The plasma processing apparatus using the mechanical clamp system will be described later. The RF application method of the illustrated plasma processing apparatus 10 employs a split method in which RF power is applied to both the upper and lower electrodes 14 and 16 by the RF power splitter 22, but the present invention is not limited thereto. For example, an anode coupling method and a cathode coupling method including this split method can be alternatively selected.

The periphery of the upper electrode 14 and the lower electrode 16 are covered by upper and lower quartz jigs 18 and 20, respectively. These quartz jigs 18 and 20 have a so-called focus ring function of concentrating plasma between the parallel plate electrodes. The upper and lower quartz jigs 18 and 20 are detachable during mechanical cleaning. Deposits of reaction products are deposited on portions of the upper and lower quartz jigs 18 and 20 near the upper and lower electrodes. In particular, deposits are conspicuous in a region having a width of about 12 mm from the inside (inner edge) of the lower quartz jig 20 near the lower electrode 16. Therefore, this portion is particularly valuable in providing a stepped portion.

For this reason, in the present invention, the upper and lower quartz jigs 18 and 20 have a surface composed of a plurality of small areas divided by steps at portions where deposits of reaction products are deposited, that is, substantially vertical surfaces. It has a surface (hereinafter, collectively referred to as a step-processed portion) divided into concave portions or convex portions separated by various steps. In particular, since deposits are remarkably deposited on the lower quartz jig 20 near the lower electrode 16, the lower electrode 1
In the vicinity of 6, a stepped portion is preferably provided. Further, in a processing apparatus using an electrostatic chuck, when the deposit deposited on the jig located near the wafer is peeled, the peeled deposit is drawn to the electrostatic chuck. As a result, there arises a problem that the wafer cannot be fixed. In this sense, in a processing apparatus using an electrostatic chuck, it is particularly effective to provide a stepped portion.

Here, FIG. 2A is a top view of an example of a stepped portion formed on the lower quartz jig 20, and FIG. 2B is a partially enlarged view of a portion α in FIG. 2A. , D− in FIG.
FIG. 2C shows a partial cross-sectional view taken along the line d ′. FIG.
The stepped portion 30 formed on the surface of the lower quartz jig 20 shown in (a), (b), and (c) is entirely radial, that is, the inner edge along the inner edge of the annular lower quartz jig 20. In the illustrated example, a 1 mm width × 12 mm length × 0.3 mm (3 mm) having a predetermined width, a predetermined length, and a predetermined depth (step) formed at a predetermined pitch substantially perpendicularly to
00 μm) is a rectangular groove (recess) 30 a having a depth (step). The bottom of these rectangular grooves 30a and the rectangular grooves 30
The surfaces between (a) (the surfaces of the convex portions) are substantially flat. Although not shown, the upper quartz jig 18 provided around the upper electrode 14 is also similarly processed as a stepped portion so that the entire inner edge of the surface of the upper quartz jig 18 has a width of 1 mm × 1.
2 mm length x 300 μm depth (step) rectangular groove of 2 mm
They are arranged radially at a pitch.

Here, in order to clarify the operation and effect of the present invention, an experiment was conducted using the plasma processing apparatus 10 shown in FIG. The plasma concentrates between the parallel plate electrodes by the upper quartz jig 18 and the lower quartz jig 20 that cover the periphery of the upper electrode 14 and the lower electrode 16, respectively, and the reaction is generated in the upper and lower quartz jigs 18 and 20. Deposits are deposited on the lower quartz jig 20 in the vicinity of the lower electrode 16, and the deposits of reaction products are remarkable, and this is shown in FIG. Thus, only the surface region 28 near the lower electrode 16 of the lower quartz jig 20 has various patterns as shown in FIGS. 3B to 3E which are partially enlarged views of the α portion in FIG. Was given.

The pattern A shown in FIG. 3F, which is a partial cross-sectional view taken along the line aa ′ in FIG. 3B and FIG.
This is the lower quartz jig 20 immediately after being formed by mechanical processing, and its surface region 28 remains an untreated surface untreated surface. In this case, the surface roughness of the lower quartz jig 20 is 1.57 μm in center line average roughness (Ra), 9.25 μm in ten-point average roughness (Rz), and maximum height (Rma).
x) is 10.5 μm. FIG. 3G is a partial cross-sectional view taken along line bb ′ of FIGS. 3C and 3C.
Is a lower quartz jig 20 having its surface region 28 subjected to a frost treatment 28b, and the surface roughness of the finished portion 28a is represented by a center line average roughness (Ra) of 3.
The average height was 92 μm, the ten-point average roughness (Rz) was 23.0 μm, and the maximum height (Rmax) was 27.5 μm.
The frosting process 28b was performed within the 15 mm width of the inner edge portion of the surface of the lower quartz jig 20.

3 (d) and c- in FIG. 3 (d).
The pattern C shown in FIG. 3H, which is a partial cross-sectional view taken along the line c ′, is obtained by machining a groove pattern in the surface region 28 of the lower quartz jig 20 and is formed as the stepped portion 30 of the present invention. A substantially concentric groove 30c (the portion of the orientation flat is not circular, but in the present invention, this portion is substantially circular). This substantially concentric groove 30c is
The surface region 28 of the lower stone Eiji tool 20 away 2mm from the inner edge of the surface of the lower stone Eiji tool 20, a groove pattern having a width 3mm and a depth which is arranged substantially concentrically (step) 50 [mu] m. 3 (e) and FIG. 3 (i), which is a partial cross-sectional view taken along line dd 'of FIG. This is a rectangular groove (recess) 30d radially formed as the stepped portion 30 of the present invention as the stepped portion 30 of the present invention. The rectangular grooves 30d formed radially are formed on the inner edge of the surface of the lower quartz jig 20 in the rectangular grooves 30a shown in FIGS.
A rectangular groove pattern having a width of 1 mm × 12 mm long and a depth (step) of 50 μm radially formed at a pitch of 2 mm and having the same groove pattern except for the depth and the depth (step). Specifically, the formation of the groove patterns of the patterns C and D was performed by mechanical grinding using a diamond jig. The bottom surface of the ground groove has the same roughness as the surface of the quartz jig before processing.

The lower quartz jig 20 was mounted in the plasma processing apparatus 10 shown in FIG. 1 to generate reactive plasma, and the wafer 26 was dry-etched. In this experiment, reactive plasma was used for dry etching. As shown in FIG. 4, the structure of the wafer 26 is such that a silicon dioxide film 34 is formed on a Si substrate 32 at a thickness of 1.0 μm, and a mask pattern of a photoresist 36 is formed thereon at a thickness of 1.2 μm. did. As the mask, a mask having a hole shape 38 having a diameter of 0.30 μm was used. CF ₄ as a dry etching gas,
A mixed gas of an etchant gas of CHF ₃ and Ar was used. Table 1 shows the plasma generation conditions used.

[0028]

Table 2 shows the results. Table 2 shows how much the detachment of the adhered substance progressed when a large number of wafers were continuously dry-etched. Here, the discharge time is a time obtained by integrating the plasma discharge time required for processing each wafer. For pattern A, 2
With about 5 hours of discharge, the deposits were peeled off in all areas.
In pattern B, the peeled area was 10% in 20 hours, and 3%
In 5 hours, the deposits in all areas were peeled off.

[0030]

As can be seen from the comparison with the pattern A, the adhesion between the adhered substance and the base material is improved even with the minute unevenness due to the frost processing of the pattern B. But,
Considering that the generation of particles starts from the point at which the adhering matter is separated, a significant improvement in the operation rate of the apparatus cannot be expected.

On the other hand, the stepped portion 30 which is a feature of the present invention
Pattern C and pattern D having (30c, 30d)
In each case, the reaction product was not peeled off at all for a discharge time of 40 hours. From this, pattern C and pattern D
It was found that the peeling off of the adhered substance was much more effective than the improvement of the adhesive force due to the minute unevenness by the frost treatment obtained in the pattern B.

Table 3 shows a comparison of the adhesion of the reaction product measured by a peeling method in a 20-hour discharge. As a result, the pattern A was 3 × 10 ⁵ dyne / cm.
² or less, pattern B is 3-7 × 10 ⁵ dyne / c
m ² , pattern C is 20 to 30 × 10 ⁵ dyne / cm
^2. Pattern D was found to exhibit an adhesive force of 30 × 10 ⁵ dyne / cm ² or more. From these results, it was found that the patterns C and D were able to maintain a large adhesive force as compared with the prior art. In particular, when the pattern D is compared with the untreated area, the adhesive force is improved by at least about 10 times.

[0034]

Regarding the mechanism of the detachment of the adhered substance, when the internal stress of the adhered substance is increased, the adherence to the underlying substrate is exceeded, and the adhered substance cannot be resisted. Are known. But,
From the above experimental results, the following findings can be further found.

One of the findings is that the easiness of detachment of the attached matter is related to the absolute amount of displacement limited according to the internal stress of the attached matter. The amount of displacement generated according to the internal stress of the attached matter can be expressed by the following equation when the attached matter is captured one-dimensionally. (Displacement of attached matter) = (internal stress of attached matter × length of attached matter) / (Young's modulus of attached matter) That is, the larger the internal stress of the attached matter and the larger the size of the attached matter, the more the attached matter Is easily peeled off. Further, the present experimental results show that it is effective to provide an appropriate step to limit the size of the deposit. It is considered that the reason why the pattern D has a larger adhesive force than the pattern C is an effect that the size of the attached matter of the pattern D is divided into smaller portions by the step. As described above, a deposit is deposited in a ring shape on the quartz jig surface near the electrode. In order to divide this deposit into smaller pieces,
The radial pattern D is more effective than the concentric pattern C.

In the case of the pattern A, when deposits were visually observed after depositing for 20 hours, deposits were conspicuous in a band-like region having a width of about 12 mm from the inside (inner edge) of the lower quartz jig 20. there were. Then, cracks were generated radially, and peeling occurred. It can be understood that such radial cracks are generated because thermal expansion and thermal contraction occur due to a temperature change accompanying ON / OFF of plasma, and circumferential stress is generated inside the adhered film. Thus, at least at the time of the discharge time of 20 hours,
Since circumferential stress is the main cause of peeling, (length of the attached matter) in the above equation can be considered to be the circumferential length. The pattern D divides the belt-like adhered film into small regions in the circumferential direction, so that (the length of the adhered substance) is reduced, (the amount of displacement of the adhered substance) is limited, and peeling can be effectively prevented. It can be understood.

Data supporting the effect of such division are shown in FIGS. FIG. 5 shows the relationship between the discharge time and the thickness of the deposit. For example, a deposit of about 300 μm is deposited by discharge for 20 hours, and thereafter, the deposited film thickness increases in proportion to the discharge time. As described above, a large internal stress is generated in the adhesion layer having a thickness of several hundred μm. Therefore, when the film thickness exceeds a certain value, the adhesive force cannot fully withstand the internal stress of the adhered substance, and the adhered substance peels off. However, as shown in FIG. 6, the detachment of the attached matter depends not only on the thickness of the attached matter but also on the attached surface area.

That is, the smaller the area of the divided small area is, the more it is possible to prevent the detachment of a thicker deposit. Specifically, the area is 400 mm ² , 39.5 mm ² ,
At 0.02 mm ² , about 300 μm, 6
The effect of preventing detachment of the attached matter having a thickness of 00 μm and 1200 μm was confirmed. Here, the height of the step dividing the small area is 50 μm. The results in FIG. 6 show that, in addition to the conventional knowledge that peeling is more likely to occur as the stress of the attached matter increases, peeling can be suppressed by restricting the size of the attached matter by small areas divided by steps. The new findings obtained by the present invention are nothing less than correct. The area of the small region is determined in consideration of requirements such as ease of processing and the like within an appropriate range in order to obtain an effect of preventing separation of deposits deposited in each apparatus by limiting the size. For example, if the thickness of the deposit is 3
If it is about 00 μm, it is about 400 mm ² or less, and if it is about 600 μm, it is about 40 mm ² or less. The lower limit is not limited to 0.02 mm ² experimentally confirmed in FIG. For example, it can be set to about 1 × 10 ⁻³ mm ² . However, in consideration of the easiness of processing, it is usually preferable that the thickness be about 0.5 mm ² or more.

The thickness of the adhered film is about 300 μm at a discharge time of 20 hours, and thereafter increases almost in proportion to the time. 5 which is the height of the step between the patterns C and D
0 μm is much smaller for the thickness of this deposited film.
Since a high separation preventing effect can be obtained with such a small step, it can be understood that whether or not the adhered film is separated depends on the displacement of a portion having a certain thickness near the interface with the quartz jig. This "certain thickness" is considered to vary depending on the composition of the deposits and the like, but it is about 50 μm or less under the etching conditions shown in Table 1, and it is possible to divide the deposited film of that thickness at a step of 50 μm. I understand that there was. Further, even if the height of the step is as small as 50 μm, the width of the groove, that is, the distance between the small projecting regions divided by the step is large. For example, in the case of pattern D, it is 1 mm, which is about 3.3 times the deposited film thickness in a discharge time of 20 hours,
It is about 1.7 times the deposited film thickness in 40 hours. The film thickness is about 1.3 times as large as the film thickness assumed to increase in proportion to the discharge time up to the discharge time of 50 hours. Further, the film thickness shown in FIG. 5 is a value at the inner edge portion of the lower quartz jig having the largest deposited film thickness, and the film thickness decreases as the distance from the inner edge increases. Further, the deposition of the deposits generated by the plasma does not necessarily proceed conformally (in the same direction), and generally becomes thin on the side wall of the step. Therefore, it is considered that the step that divides the small convex region and the small concave region does not disappear even after a long-time discharge, at least in most of the step processed portion. That is, even after a long-time discharge, the deposit is deposited on the substrate having a step, and is effectively divided by the step. And separation is prevented by being divided by the step.

On the other hand, a nailing effect is known in which the irregularities on the adhered surface improve the adherence of the adhered substance. However, in the pattern B having minute irregularities, the pattern C and the pattern D separated by a step are peeled off. What is easy is
This indicates that the nailing effect depends on the height of the step.

FIG. 7 shows data supporting this. FIG.
Shows the relationship between the height of the step in the pattern D in which the area of the divided small area is 12 mm ² and the adhesive force of the deposit when plasma discharge is performed for 20 hours. FIG.
According to this, as the film thickness of the deposits increases, that is, as the stress of the deposits increases, the detachment of the deposits is more likely to occur.
However, if the step is increased accordingly, the detachment of the adhered substance is less likely to occur. In this experimental result, the adhesion was 3
At ７7 × 10 ⁵ dyne / cm ² or less, peeling of the deposits was liable to occur, but 15 × 10 ⁵ dyne / cm ² can be reliably prevented.
^{The step at which 5} dyne / cm ² or more was obtained was 30 μm. Further, at a step of 50 μm, 30 × 10
Adhesive force exceeding ⁵ dyne / cm ² was obtained.

The step of 30 μm is considered to be very small for the deposit having a thickness of 300 μm. However, it can be understood that a certain degree of nailing effect is obtained even with such a small step. The thickness of 300 μm is 12 μm.
It is much smaller than a pattern with dimensions of mm ² .
Therefore, it is not essential that unevenness is present at a high density in order to obtain a nailing effect.
It can be understood that it suffices if there is at least one in a specific area. Thus, it can be understood that the step has an effect of pinning the film of the attached matter (hereinafter, referred to as a “pinning effect”).

The phenomenon that the remarkable separation preventing effect was not obtained by the frost treatment of the pattern B can be understood as follows. First, only the fine irregularities are formed on the surface of the quartz jig subjected to the frost treatment, and the maximum height (Rmax) is only 27.5 μm. Since the height of the unevenness is small as described above, the effect of dividing the adhesion film and the effect of nailing are small. Further, the concave portion and the convex portion are continuously connected by an inclined portion, and a small region divided by a clear step is not formed. Therefore, the effect of dividing the adhesion film and limiting the displacement is small. Even if the height can be further increased, since the distance between the adjacent convex portions is small, the deposits deposited on the adjacent convex portions are connected to each other, and the adhesive film is effectively divided. Can not do. In other words, the frosting process does not form a recess having a certain width, which is necessary for dividing the adhered film and is separated by a distinct step. On the other hand, pattern C
The surface of the quartz jig having D and D is divided into a plurality of small regions by distinct steps having a height of 50 μm. First, the step has an effect of pinning the film of the deposit. Further, the concave small area formed at the bottom of the groove has a width of 1 mm. Therefore, the films attached to the small convex regions adjacent to each other with the groove interposed therebetween, and the film attached to the small convex regions and the film attached to the small concave regions are effectively divided.

Therefore, in the present invention, it is preferable that the steps forming the irregularities have a height sufficient to prevent the separation of the deposits. Specifically, as shown in FIG. 7, 30 μm or more, or more preferably 50 μm
Above. Each of these steps is about 1 μm compared to about 300 μm, which is the thickness of the deposit on 20 hours of discharge time.
0% and 17%. Note that the higher the step, the higher the adhesive force. Therefore, it is preferable to further increase the step. For example, as will be described later, the increase in the number of particles due to peeling was not observed even with a 50-hour discharge at a step of 300 μm. In this case, the height of the step is about 40% of the film thickness. As a matter of course, the deposition rate of the deposit differs depending on the type of the processing apparatus and the operating conditions. Further, the continuous processing time required to obtain a required apparatus operation rate or the time obtained by integrating the processing time for each wafer differs for each apparatus. A step required to prevent peeling is set in accordance with the film thickness deposited during the required continuous processing time. From the viewpoint of preventing peeling, it is preferable to increase the step. However, if the height of the step is equal to or greater than the thickness of the deposited film, no remarkable effect can be obtained even if the height is further increased. In addition, it is not preferable to increase the step more than necessary even in consideration of a decrease in the strength of the jig and an increase in processing difficulty. Further, if the step is too large, the characteristics of the processing apparatus may be adversely affected. For example, in a processing apparatus using a gas, the flow of the gas is disturbed by the steps, and as a result, the processing characteristics are adversely affected. Therefore, it is preferable that the height of the step is in a range that does not disturb the gas flow.

In this experiment, a parallel plate type plasma processing apparatus 10 as shown in FIG. 1 was used. In the case of such a plasma processing apparatus, the upper electrode 14 and the lower electrode 16 were used.
This is a structure in which the plasma is efficiently confined between them.
In the case of such a structure, a large amount of reaction products are redeposited in the vicinity of the region where the plasma terminates, forming an adhesion layer. Therefore, by providing the stepped portion on the surface of the apparatus where the reaction product is remarkably adhered, such as the surface position near the wafer 26 or the vicinity of the electrodes 14 and 16, the deposited layer of the deposit is formed. Acts more effectively on the prevention of peeling, and a greater effect can be obtained.

Next, the operation and effect of the pattern shape of the unevenness formed by the steps will be described. In this experiment, a parallel plate type plasma processing apparatus was used. In such a plasma processing apparatus, a temperature gradient centered on plasma is generated in the processing bath. Alternatively, when there is a heat source or a cooling unit in the processing tank, a temperature gradient is generated in which the effects of the heat source and the cooling unit are combined. Accordingly, a component in a direction along such a temperature gradient is generated in the internal stress of the deposit. Also, the deposit is
The film thickness often changes due to the temperature gradient, and a stress component due to the film thickness difference also occurs. In such a case, it is more effective to arrange the concave portions or the convex portions along the isothermal curve generated by the temperature gradient as in the pattern C described above.

In a single-wafer type plasma processing apparatus, periodic thermal fluctuations often occur due to plasma on / off. In this case, the internal stress of the deposit increases in a region where the amplitude of the thermal fluctuation is maximum. In this case, an internal stress is generated along the isothermal curve generated by the temperature gradient.
Therefore, it is more effective to arrange the concave portions or the convex portions along the normal direction to the isothermal curve, that is, along the temperature gradient as in the pattern D.

For example, in the etching of a low dielectric constant insulator, so-called low-temperature etching is performed in which the temperature of the lower electrode on which the wafer is mounted is set to room temperature and cooled to a much lower temperature, for example, about -50 ° C. In such a case, a large temperature gradient occurs. In general, the deposition rate of the deposit increases as the temperature decreases, so that the thickness of the deposit also increases. As a result, detachment of the attached matter is likely to occur. In such a case, if the stepped portion of the present invention is provided to prevent the detachment of the adhered substance, it is particularly effective to arrange the uneven pattern according to the temperature gradient. Further, in the case of a component using a material having a high thermal conductivity such as metal or silicon, for example, the width and speed of a temperature change generated by turning on and off the plasma are large. For this reason, detachment of the attached matter is likely to occur. In such a case, it is effective to provide the stepped portion of the present invention to prevent the detachment of the attached matter, and particularly to arrange the pattern according to the temperature gradient.

Further, the present invention can be applied not only to prevention of the detachment of the adhered substance on the surface of the component in the processing tank such as the plasma processing apparatus, but also the coating of the surface of the component in the apparatus tank can be peeled off by the same principle. It is also effective to prevent In particular, aluminum alumite may be used as a material for components inside the chamber, including the chamber itself. However, when the alumite is heated to 130 ° C. or higher, it rapidly separates due to the difference in thermal expansion coefficient from the aluminum base material. It has characteristics that make it easy to do. For this reason, in a conventional apparatus, particularly a single-wafer processing apparatus, the surface of such a component becomes hot due to the heating effect of the continuous processing, and the alumite is easily peeled off. Therefore, also in this case, by dividing the surface of the aluminum alumite into small regions by steps as in the present invention,
It is effective to maintain the adhesion between the aluminum base material and the alumite and prevent peeling.

[0051]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The processing apparatus of the present invention, a method for preventing the detachment of attached matter using the same, a method for manufacturing a semiconductor device, and components and a focus ring of the semiconductor manufacturing apparatus will be described in more detail with reference to examples. (Embodiment 1) Embodiment 1 in which the processing apparatus of the present invention is applied to a plasma processing apparatus used as a dry etching apparatus
And its modifications will be described. Using the plasma processing apparatus 10 shown in FIG. 1 as a dry etching apparatus and using the lower quartz jig 20 shown in FIGS. 2A, 2B and 2C, a semiconductor device substrate (wafer) having the structure shown in FIG. 26)
The silicon dioxide film 34 was subjected to dry etching. As described above, a rectangular groove 30a having a width of 1 mm × 12 mm and a depth (step) of 300 μm is radially arranged at a pitch of 2 mm as the stepped portion 30 on the inner edge of the surface of the lower quartz jig 20 (pattern D: FIG. 3 (e) and (i)). Similarly, for the upper quartz jig 18 installed around the upper electrode 14, the step processing portion 30 on the inner edge of the surface of the upper quartz jig 18 is 1 mm wide × 12 mm.
Rectangular grooves 30a having a length and a depth (step) of 300 μm were radially arranged at a pitch of 2 mm.

For the pattern, D, the effect of which was confirmed most in Table 3, was selected. The length is the width at which deposition was observed at pattern A in Table 2, i.e., 20 hours of discharge time, when significant (50%) delamination was observed for the flat quartz jigs (20, 18). I chose 12mm. That is, the entire length of the 12-mm-thick adhered film was set so that it could be divided in the circumferential direction. As shown in Table 3, the effect was confirmed even when the height of the step was 50 μm.
It was set to 00 μm. This height is a height corresponding to the deposited film thickness of the deposits during the above-described discharge time of 20 hours. The shape of the actually processed groove 30d has a cross-sectional shape as shown in FIG. The entire cross section has a substantially rectangular shape. The side wall is not completely perpendicular to the surface of the quartz jig 20, (18). Although not clearly shown, it has a slight unevenness and its lower end is rounded. However, the average inclination angle excluding the lower end is as large as about 80 ° or more, and can be said to be substantially vertical. As a comparative example, dry etching of the silicon dioxide film 34 using the machined flat upper and lower quartz jigs 18 and 20 as shown in FIGS. 3B and 3F was similarly performed. .

The chamber 12 was evacuated to a vacuum of about 10 ⁻⁶ Torr, and the wafer 26 was fixed on the lower electrode 14 using the electrostatic chuck 17. A mixed gas of CF ₄ , CHF ₃ etchant gas, and Ar was used as a dry etching gas introduced into the chamber 12 from the gas inlet 13 above the chamber 12. As the RF application method of the plasma processing apparatus 10, a split method of applying RF to upper and lower electrodes was adopted. The conditions shown in Table 1 above were used as the plasma generation conditions. As described above, in the present plasma processing apparatus 10, the upper and lower quartz jigs 18 and 20 surround the upper electrode 14 and the lower electrode 16.
, And the plasma is concentrated between the parallel plate electrodes, so that deposits of reaction products are deposited on the upper and lower quartz jigs 18 and 20 near the electrodes. .

Table 4 shows the case where flat upper and lower quartz jigs 18 and 20 were used as they were machined, and the case where radial regular uneven patterns (rectangular grooves 30a) were formed on the upper and lower quartz jigs 18 and 20. The result of having compared the dry etching performance with the case where the stepped part 30 which has it is installed is shown. There was no difference between the etching rate and the etching uniformity of the silicon dioxide film 34. Since there is no difference in the etching rate of polysilicon at this time, it is defined as (silicon dioxide etching rate) / (polysilicon etching rate) which is often regarded as important in a silicon dioxide dry etching process for a semiconductor integrated circuit or the like. There was no difference in the base selectivity. Also, there was no difference in the processing conversion difference with the mask or the taper angle of the etched shape. In particular, it was confirmed that there was no difference in the fine shape processing at the level of 0.30 μm in diameter and 1.0 μm in depth with respect to the etched shape. Thus, the upper and lower quartz jigs 18 and 2 are different from the basic performance of dry etching.
0 shows a rectangular groove 30 as shown in FIGS. 3 (e) and 3 (i).
It was confirmed that the provision of the stepped portion 30 having the radial uneven pattern made of “a” had no adverse effect. The gap between the upper and lower quartz jigs 18, 20 of the apparatus of FIG. 1 is about 2 mm. With respect to this gap, a step of 300 μm provided on the quartz jig corresponds to about 15%. It has been confirmed that such a step does not disturb the gas flow or change the plasma characteristics and the etching characteristics.

[0055]

However, when the step of the step processed portion is further increased, the etching characteristics, particularly the uniformity, are adversely affected. FIG. 9 shows a step of the step-processed portion and a silicon dioxide when the lower quartz jig having the step-processed portion (pattern D) shown in FIGS. 3 (e) and 3 (i) is used in the etching apparatus shown in FIG. 4 is a graph showing a relationship with etching rate uniformity. As can be seen from FIG.
In the case of 00 μm, the uniformity deteriorated to 4.9%,
In the case of μm (1.2 mm) or more, it exceeded 5%. This can be understood that the flow of the gas was disturbed by the stepped portion and the plasma and etching characteristics were changed.
Therefore, the height of the step is about 1.5 mm or less, preferably 1
mm or less. The apparatus shown in FIG. 1 is a narrow gap type etching apparatus, and the interval between the upper and lower quartz jigs 18 and 20 is as small as about 2 mm. With respect to this gap, the above-mentioned step of 1 mm corresponds to about 50%. Due to the application to the component forming such a narrow gap, the above-described limitation has been found in the height of the step processing. In other devices and other parts, it is preferable to suppress the height of the step processing to a range that does not disturb the gas flow. However, the specific upper limit of the height of the step differs for each device and component.

FIG. 10 shows the plasma discharge time and the number of particles generated in the chamber 12 in the first embodiment.
That is, it is a graph showing a relationship with the number of particles adhering to the wafer processed in the chamber 12. From FIG. 10, it can be seen that, when radial irregular patterns are formed by the rectangular grooves 30a on the upper and lower quartz jigs 18 and 20, the number of particles having a diameter of 0.25 μm or more falls within 30 even when the plasma discharge time is 50 hours.
For comparison, the case where the flat upper and lower quartz jigs 18 and 20 as they are machined are used is shown at the same time. In this case, if the plasma discharge time exceeds 20 hours, the discharge time is set to 0.1.
Particles having a diameter of 25 μm or more increased.

The product yield of the semiconductor integrated circuit was also at the conventional level, and it was confirmed that the radial uneven pattern of the stepped portion 30 of the upper and lower quartz jigs 18 and 20 had no adverse effect. In addition, no decrease in the yield was observed even in the vicinity of the plasma discharge time of 40 hours. Furthermore, even if the conventional cleaning method is used for the mechanical cleaning, the upper and lower quartz jigs 18 and 20 can be used.
Since the uneven pattern step of the stepped portion 30 is large, the problem that the uneven pattern disappears due to wear does not occur. As is clear from the above, the continuous operation time of the plasma processing apparatus 10 to which the present invention is applied can be more than doubled by applying the step processing section 30 which is a feature of the present invention. As a result, the frequency of mechanical cleaning was reduced, and the operation rate of the apparatus was improved.

The quartz jig in which the radial groove pattern is formed as described above can be used for about 1 to 1 in actual semiconductor device production.
Used continuously over the years. During that time, a high operation rate is continuously recorded without any trouble caused by the groove pattern. Further, the continuous operation has been achieved for more than 50 hours and up to 70 hours shown in FIG.
Actually, no increase in the number of particles is observed even after the continuous operation for 70 hours, and it is considered that continuous operation for a longer time is also possible. In addition, it has been confirmed that even if the pitch of the grooves is increased to 4 mm while keeping the width of the grooves at 1 mm, the problem of adhering matter peeling does not occur in 70 hours of continuous operation. However, when the pitch was widened to 6 mm, cracking of the deposits was observed. Furthermore, the groove depth of the upper quartz jig 18 is 200 μm for the upper quartz jig 18 in which the deposited film thickness of the deposit is only about １ ／ as compared with the lower quartz jig 20.
It has been confirmed that even if it is reduced to m, the adhered substance does not peel off.

The quartz jigs (18, 20) on which deposits are deposited by continuous operation for 70 hours can be used repeatedly by removing the deposited film by a cleaning treatment.
The removal of the adhered film can be performed without damaging the quartz jig. That is, the deposited film adhering to the protrusions between the grooves is peeled off by being immersed in an organic solvent. And
The deposited film in the groove can be removed by brushing. Since the part inside the groove and the part between the grooves are separated and removed,
It can be seen that the deposited film adhered during the discharge time of 70 hours is divided by the groove of 1 mm width and 300 μm depth provided in the lower quartz jig 20. There is no shortening of the life of the quartz jig due to the formation of the groove pattern and the continuous operation for 70 hours. After continuous operation for 70 hours, it is observed that the range in which deposits on the lower quartz jig 20 can be visually confirmed is further expanded outwardly after 20 hours. Therefore, it is effective to further increase the length of the radial groove and to completely divide the adhered film in the circumferential direction even at this point in order to further extend the continuous operation time.

It should be noted that the deposited film formed by continuous operation for a long time has a large thickness distribution in the diameter direction.
Such a film thickness distribution generates an internal stress in the diameter direction. In order to prevent the separation due to the internal stress, it is conceivable that, in addition to the radial grooves such as the pattern D, concentric grooves such as the pattern C are formed, and the adhesive film is divided in the diameter direction. . In this case, the deposited film is not only divided one-dimensionally by a one-dimensional pattern such as the pattern C or D, but is also divided by a two-dimensional pattern such as a combination of the patterns C and D. It will be dimensionally divided. However, two-dimensional groove pattern formation leads to an increase in pattern formation cost.
Further, there is a possibility that a problem of a decrease in the strength of the quartz jig may occur. Furthermore, in cleaning jigs on which deposits have accumulated,
The difficulty of removing the deposits attached to the recesses increases. If a cleaning solution having a high etching action capable of removing the deposit only by the chemical action is used, the removal may be possible. However, the jig is damaged and the life of the jig is shortened. Considering such requirements comprehensively, the quartz jigs 20 and 1 of the etching apparatus targeted in this embodiment are considered.
In No. 8, it can be determined that it is preferable to provide only a radial one-dimensional pattern.

It is preferable that the step (the step processing portion 30) for dividing the small area is substantially vertical as shown in the example of FIG. 8 in order to effectively divide the deposited film. . Specifically, the average inclination angle of the side wall is about 75 ° or more, and more preferably about 80 ° or more. However, it need not be completely vertical. Further, the angle of inclination required for effective division varies depending on the composition of the deposits, the deposition mechanism, and the like. Therefore, the angle of the step is sufficiently large,
As long as the deposited film can be effectively divided, an appropriate step shape may be determined according to each device and component and operating conditions. Also, not only the tilt angle itself,
It is also important that a clear bend point exists between the small region to be divided and the step, and the small region is divided by the clear step.

In this embodiment, the width of the groove was 1 mm. It is possible to change this width within a certain range. However, it is not preferable to make the groove width too large in order to obtain the necessary effect of preventing the attached matter from peeling. In the case of the lower quartz jig 20 of the etching apparatus of the present embodiment, as described above, it is considered that a crack was generated in the adhered film at a groove pitch of 1 mm and a groove pitch of 6 mm, that is, a width of a convex portion between grooves of 5 mm. Then, it is preferable that the width of the groove is also less than 5 mm. On the other hand, if the groove width is too small, as described above, the films attached to the adjacent small convex portions are connected to each other, and the attached film cannot be effectively divided. In this example, it was confirmed that the groove having a width of 1 mm provided in the lower quartz jig 20 was sufficient to divide the deposited film formed during the discharge time of 70 hours. As mentioned above, this width is large compared to the deposited film thickness measured during the 40 hour discharge time. The minimum value of the groove width required to divide the deposited film varies depending on the apparatus and its operating conditions. However, in general, it is preferable that the thickness is greater than, or at least equal to or greater than, the thickness of the deposited film formed during the discharge time between cleanings required to obtain the required operation rate. On the other hand, in consideration of ease of processing, when the grooves are formed by mechanical grinding, the groove width is preferably set to about 0.5 mm or more.

As described above, in order to prevent the separation by the action of dividing the deposited film, it is necessary to divide the deposited film formed during the cumulative processing time determined to obtain the required operation rate. It is necessary to provide a groove so that a suitable step is formed. That is, the depth of the groove (the height of the step) is sufficiently large, the angle of the side wall of the groove (the angle of the step) is sufficiently large, and the width of the groove (divided by the step) is set so that the deposited film is effectively divided. It is necessary that the pitch of the grooves (the width of the small convex region) is not too large, so long as the distance between the adjacent small convex regions is sufficiently large and not too large. The deposited film does not necessarily have to be completely separated, but it limits the length of the deposit and limits its displacement,
It is necessary to divide so as to have an effect of preventing peeling.

The small area divided by the step of the step processing section 30 in the present invention is not necessarily limited to an area whose periphery is divided by a surface. What is important is that, as described above, the surface area of the deposit where the deposit adheres by operation of the apparatus, that is, where the adhesion of the deposit is desired to be maintained, is divided into small areas by steps. Therefore, if there is a step that divides the step processing section 30 into a plurality of small areas,
Preferably, if the step has a height sufficient to prevent sediment separation, specifically, for example, if it includes a portion having a size of 30 μm or more, the step processed portion of the present invention is particularly limited. Not a target but various modifications are possible. For example, the lower quartz jig 20 shown in FIGS.
The small area like the step processing part 30 of the rectangular sloped groove 30
e, or a small area such as the stepped portion 30 of the lower quartz jig 20 shown in FIGS. 12A and 12B, the V-shaped inclined groove 30f.
And the like that is divided into a slab shape by the

As in the apparatus of this embodiment, the chamber 12
Is simple and has a good symmetry, FIG.
(B), (c) and steps formed by the rectangular grooves 30a, 30d radially arranged as shown in FIGS. 3 (e), (i),
Alternatively, it is particularly effective to use a repetitive pattern having good symmetry, such as a step formed by concentric grooves 30c arranged concentrically as shown in FIGS. 3D and 3H. As described above, the plurality of divided small areas of the stepped portion 30 are preferably arranged in a regular pattern, but the present invention is not limited to this.

It is preferable that each of the plurality of divided small areas of the stepped portion 30 is substantially flat. However, it need not be perfectly flat. In fact, as mentioned above, the machined surface has some surface roughness. If the surface roughness is much smaller than the step, it can be said that each of the small regions divided by the step is substantially flat. Further, even when a part or all of the small area is roughened by using the conventional frost processing, the degree of the roughening is not large, and the area is remarkably small as compared with the step dividing the small area. Then, it can be said that each of the small regions is substantially flat. Even if the boundary region between the step portion and the small region has a rounded shape, if the ratio of the boundary region to each of the small regions is sufficiently small, each of the small regions is still substantially flat. It can be said that In addition, it is also allowed that each of the small regions becomes a curved surface as a whole. If a stepped portion is formed on the surface of the curved surface of the device component, a small area of the curved surface is inevitably formed. Also, depending on the shape of the jig used for the mechanical grinding, the bottom surface of the groove, that is, the small concave area may be curved. Even in such a case, if the radius of curvature is large and the change in height in each small area is in a range that is sufficiently small as compared with the height of the step dividing the small area, again, , Each of the small areas can be said to be substantially flat.

In this embodiment, the plasma processing apparatus 10 of the type in which the wafer 26 is fixed to the lower electrode 16 by the electrostatic chuck is used. However, the plasma processing apparatus 40 shown in FIG. A similar application is possible. Plasma processing apparatus 40 shown in FIG.
Is a method of fixing the plasma processing apparatus 10 and the wafer 26 to the lower electrode 16 shown in FIG.
6 has basically the same configuration except for the configuration of the jig that covers the periphery of 6, the same components are denoted by the same reference numerals, and description thereof will be omitted.

The plasma processing apparatus 40 is a dry etching apparatus having a parallel plate structure with a narrow gap, and includes a chamber 12, an upper electrode 14 having a gas inlet 13, a lower electrode 16, and a An alumite jig 42 is arranged to cover the lower electrode 16, and is arranged to cover the lower electrode 16, facing the aluminum alumite jig 42 and under the aluminum alumite jig 42, and placed on the lower electrode 16. An aluminum alumite clamp ring (mechanical clamp) 44 for mechanically clamping the outer peripheral portion of the wafer 26 from above, an RF power splitter 22, and an RF power supply 24 are provided. Here, in the illustrated plasma processing apparatus 40, at least one of the aluminum alumite jig 42 and the aluminum alumite clamp ring 44
A surface composed of a plurality of small areas divided by a step, for example, a portion divided into a concave or a convex section divided by a step (see FIGS. 2 and 3) which is a feature of the present invention.
Are provided near the upper and lower electrodes 14 and 16.

As described above, it was confirmed that even when the mechanical clamp was provided with the stepped portion of the present invention, it did not cause abnormal discharge or the like and did not adversely affect the processing performance. That is, as in the illustrated plasma processing apparatus 40, a mechanical clamp 44 made of alumite is used, and the mechanical clamp 44 is attached to the mechanical clamp 44, for example, as described above with reference to FIGS. 2 (a) to 2 (c) and 3 ( e) Rectangular grooves 30a and 30 like pattern D shown in (i).
Degradation of the processing performance due to the provision of the stepped portion 30 by applying a radially concave and convex pattern made of concentric circular grooves 30c such as a radial concave and convex pattern composed of d and a pattern C shown in FIGS. 3 (d) and 3 (h). I couldn't see it. In addition, the detachment of the deposits was suppressed, and the continuous operation time of the apparatus could be extended.

Although the embodiment in which the present invention is applied to the plasma processing apparatus used as a dry etching apparatus has been described above, the present invention is not limited to these embodiments, and may be variously modified. It is applicable to a processing device. For example, the present invention can be suitably applied to a device such as a CVD device in which a deposit containing a reaction product is formed on the surface of a component in a chamber. In particular, it is more effective to apply the present invention to a processing device used in a manufacturing process of a semiconductor device such as a semiconductor integrated circuit and a very fine semiconductor integrated circuit.

(Embodiment 2) Another embodiment 2 in which the processing apparatus of the present invention is applied to a plasma processing apparatus used as a dry etching apparatus and its modification will be described below. FIG. 14 is a schematic cross-sectional view illustrating a schematic configuration of a plasma processing apparatus 50 according to the second embodiment. The plasma processing apparatus 50 shown in FIG.
And the upper electrode 52 and the method of applying RF power to the upper electrode 52 are basically the same except that the anode coupling method is used. And a description thereof will be omitted.

Similarly, a plasma processing apparatus 50 shown in FIG. 14 is a dry etching apparatus having a parallel plate structure with a narrow gap, and is disposed at the center of the chamber 12 and at the upper part of the chamber 12 so that an etching gas can be introduced. An aluminum alumite upper electrode 52 in which a gas inlet 53 and a plurality of gas blowing holes 55 for blowing the introduced etching gas into the chamber 12, the lower electrode 16, and the upper electrode 14 are covered so as to cover the same. Aluminum alumite jig 42 which is arranged in
The wafer 2 placed on the lower electrode 16 so as to cover the lower electrode 16 so as to cover the lower electrode 16 and to face the lower electrode 16
An aluminum alumite clamp ring (mechanical clamp) 44 for mechanically clamping the outer peripheral portion of 6 from above,
And an RF power supply 24 for applying (supplying) RF power to the upper electrode 52.

Here, in the illustrated plasma processing apparatus 50, the chamber 12 can be evacuated to a degree of vacuum of about 10 ⁻⁶ Torr, and a lower electrode 16 is supported inside the chamber. Upper electrode 5 facing
2 form a parallel plate electrode. The wafer 26 is fixed on the lower electrode 16 by using an aluminum alumite clamp 44. The upper electrode 52 is provided with a gas inlet through which an etching gas can be introduced, so that the etching gas can be introduced into the chamber. The present plasma processing apparatus 5
As the RF application method of 0, an anode coupling method of applying RF power to the upper electrode 52 is adopted, but the cathode coupling method and the split method can be alternatively selected. Upper electrode 52 and lower electrode 1
The periphery of 6 is covered with an aluminum anodized jig 42 and an aluminum anodized clamp 44. In this embodiment, the upper electrode 52 itself is also made of aluminum alumite.

Here, the upper electrode 52 made of aluminum anodized
Was processed so as to have a constant surface shape to form a stepped portion 30 which is a feature of the present invention. At this time, the upper electrode 52 was formed by subjecting the aluminum base material to a stepping process, and then forming an alumite treatment to about 20 μm. The surface shape of the aluminum base material is, as shown in FIG.
6 is 1 mm wide and 10 mm deep on the surface of
The rectangular grooves 30 g of 0 μm were arranged in a grid pattern at a pitch of 2 mm within a range not overlapping the gas blowing holes 55.
The hole diameter of the gas blowing hole 55 is 0.5 mm.

According to the present embodiment, dry etching of the polysilicon film 35 was performed using the plasma processing apparatus 50 of the present invention. As a comparative example, dry etching of the polysilicon film 35 was performed in the same manner using a flat upper electrode in which no grid-like rectangular grooves were formed. FIG. 16 shows the structure of the wafer 26 used in this embodiment. In the wafer 26 used in this embodiment, a silicon dioxide film 34 having a thickness of 10 nm is formed on a Si substrate 32, a polysilicon film 35 having a thickness of 0.25 μm is formed thereon, A 1 μm-thick mask pattern is formed. A mask having a 0.35 μm level line and space shape was used as the mask. As a gas for dry etching, a mixed gas of chlorine gas and oxygen was used. Table 5 shows the plasma generation conditions.
Shown in

[0077]

Table 6 shows dry etching between the case of using the conventional flat upper electrode and the case of using the upper electrode 52 provided with the stepped portion 30 having a grid-like uneven pattern composed of rectangular grooves 30g. The results of comparing the performance are shown. There was no difference between the etching rate and the etching uniformity of the polysilicon film 35. In addition, since there is no difference in the etching rate of silicon dioxide at this time, it is defined as (polysilicon etch rate) / (silicon dioxide etch rate) which is often regarded as important in a polysilicon dry etching process for a semiconductor integrated circuit or the like. There is no difference in the base selection ratio. There is no difference in the processing conversion difference from the mask. As a result, it was confirmed that even if the upper electrode 52 was provided with a grid-like uneven pattern formed by the rectangular grooves 30g on the basic performance of the dry etching, there was no adverse effect. Upper electrode 52
In general, the components such as are formed by a relatively smooth plane to avoid electric field concentration and abnormal discharge in a discontinuous shape part. There was no effect, and it was shown that the processing performance was not affected.

[0079]

FIG. 17 shows a plasma processing apparatus 50 shown in FIG. 14 in which an upper electrode 52 provided with a stepped portion 30 having a grid-like uneven pattern formed by rectangular grooves 30g to which the present invention is applied and a conventional upper electrode. 7 is a graph showing the relationship between the plasma discharge time and the number of anodized alumite on the wafer 26 in the case of using. In the case of the present invention in which a checkerboard-like uneven pattern formed by the rectangular grooves 30g is provided on the upper electrode 52, the number of alumite having a diameter of 0.30 μm or more falls within 30 even if the discharge time is 200 hours. On the other hand, for comparison, a case where a flat conventional upper electrode is used is also shown. In this case, when the discharge time exceeds 100 hours, the number of dropped alumite increases. In other words, it can be seen that 100 hours of discharge time is the limit time of use of the conventional upper electrode.

The product yield of the semiconductor integrated circuit is also at the conventional level, and the rectangular groove 3 of the upper electrode 52 is formed.
It was confirmed that the grid pattern of 0 g had no adverse effect. No decrease in product yield was observed even near the plasma discharge time of 200 hours. As described above, by applying the present invention, the continuous operation of the plasma processing apparatus can be improved about twice as compared with the conventional one, the operation rate of the apparatus can be improved, and the running cost can be reduced.

As described above, various embodiments in which the processing apparatus of the present invention is applied to a dry etching apparatus will be described, and the reaction products generated when dry etching a wafer for manufacturing a semiconductor device such as a semiconductor integrated circuit will be described. The effect of preventing the adhered material and peeling of the coating on the surface of the component part has been described. However, the present invention is not limited to this, and at least a part of the components in the processing tank of the processing apparatus is formed on a surface composed of a plurality of small areas divided by a step, for example, a concave or convex section separated by the step. As long as it is provided with a divided portion, that is, a step processing portion referred to in the present invention, any processing device, any processing device, and any known processing device can be used. Of course, it is applicable.

Although the embodiment shows an example in which a stepped portion is provided on a quartz jig, for example, it is also effective to provide a similar processed portion on a ceramic jig. Further, the present invention can be applied not only to the focus ring and the clamp shown in the embodiment but also to various components. For example,
It is also effective to provide the stepped portion of the present invention in a bell jar of an ECR type etching apparatus or an ICP type etching apparatus. Further, the present invention can be suitably applied to a CVD apparatus, a sputtering apparatus, and the like. Further, in the embodiments, the case where the present invention is applied to a narrow gap type apparatus in which it is difficult to perform dry cleaning effectively is described. However, even in an apparatus for performing dry cleaning, if the stepped portion of the present invention is provided, the frequency of dry cleaning can be reduced, and the operation rate can be further improved.

The processing apparatus according to the present invention, the method for preventing the separation of deposits using the same, the method for manufacturing a semiconductor device, and the components and focus ring of the semiconductor manufacturing apparatus have been described in detail with reference to various embodiments. The present invention is not limited to the above embodiments, and various improvements and modifications may be made without departing from the spirit of the present invention.

[0085]

As described in detail above, according to the present invention,
Suppresses the adhesion of reaction products and the coating on the surface of the equipment, and reduces the number of particles in the chamber.This improves the equipment operation rate and reduces running costs while maintaining the conventional performance and product yield. It has an excellent effect. Therefore, the processing apparatus of the present invention, the method for preventing the detachment of attached matter using the same, the method for manufacturing a semiconductor device, and the components and focus ring of the semiconductor manufacturing apparatus are extremely useful in industry.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view illustrating a configuration of an embodiment of a plasma processing apparatus for performing a dry etching process using a processing apparatus according to the present invention.

2 (a), (b) and (c) are top views of an embodiment of a lower quartz jig used in the plasma processing apparatus shown in FIG. 1, respectively. It is a figure and its dd 'line cutting | disconnection partial sectional view.

3A is a top view of an embodiment of a lower quartz jig used in the plasma processing apparatus shown in FIG. 1 and a wafer disposed at the center thereof, and FIGS.
(D) and (e) are partial enlarged views showing details of the α portion of the lower quartz jig shown in (a), respectively.
(G), (h) and (i) are the a-
FIG. 3 is a partial cross-sectional view taken along line a ′, line bb ′ in FIG. 3C, line cc ′ in line (d), and line dd ′ in line (e).

FIG. 4 is a partial cross-sectional view showing one example of a structure of a wafer to be dry-etched by the plasma processing apparatus shown in FIG. 1;

5 is a graph showing a relationship between a discharge time and a film thickness of a deposit deposited during operation of the apparatus when dry etching is performed by the plasma processing apparatus shown in FIG.

FIG. 6 is a graph showing the relationship between the thickness of an adhered substance, the area of a divided small region of the present invention, and the presence or absence of peeling in the plasma processing apparatus shown in FIG.

FIG. 7 shows a plasma processing apparatus shown in FIG.
It is a graph which shows the relationship between the height of the level | step difference of a level | step difference processing part, and the adhesive force of a deposit when using the lower quartz jig which has the level | step difference processing part (pattern D) shown to (e) and (i).

8 is a schematic diagram showing a cross-sectional shape of a groove formed in a lower quartz jig in the plasma processing apparatus shown in FIG.

FIG. 9 shows the plasma processing apparatus shown in FIG.
It is a graph which shows the relationship between the height of the step of the step processing part, and silicon dioxide etching uniformity when the lower quartz jig which has the step processing part (pattern D) shown in (e) and (i) is used.

FIG. 10 shows the discharge time and the discharge time in the chamber when a lower quartz jig having a stepped portion (pattern D) to which the present invention is applied and a conventional lower quartz jig are used in the plasma processing apparatus shown in FIG. 6 is a graph showing a relationship with the number of particles.

11A is a front view of another embodiment of the lower quartz jig used in the plasma processing apparatus shown in FIG. 1, and FIG. 11B is a sectional view taken along line ee ′ of FIG. It is sectional drawing.

12 (a) is a front view of another embodiment of the lower quartz jig used in the plasma processing apparatus shown in FIG. 1, and FIG. 12 (b) is a section taken along line ff ′ of FIG. It is sectional drawing.

FIG. 13 is a schematic cross-sectional view illustrating a configuration of another embodiment of a plasma processing apparatus that performs a dry etching process using the processing apparatus according to the present invention.

FIG. 14 is a schematic cross-sectional view illustrating a configuration of another embodiment of a plasma processing apparatus that performs a dry etching process using the processing apparatus according to the present invention.

15 (a) is a front view of an embodiment of an aluminum alumite upper electrode used in the plasma processing apparatus shown in FIG. 14, and FIG. 15 (b) is a section taken along line GG ′ of FIG. 15 (a). It is sectional drawing.

16 is a partial cross-sectional view showing one example of a structure of a wafer to be dry-etched by the plasma processing apparatus shown in FIG.

FIG. 17 shows a plasma processing apparatus shown in FIG. 14 in which an upper electrode having a stepped portion (a grid-like uneven pattern formed by rectangular grooves) to which the present invention is applied and a conventional upper electrode are used. 5 is a graph showing a relationship between time and the number of alumites dropped on a wafer.

[Explanation of symbols]

 10, 40, 50 Plasma processing apparatus 12 Chamber 13, 53 Gas inlet 14 Upper electrode 16 Lower electrode 17 Electrostatic chuck 18 Upper quartz jig 20 Lower quartz jig 22 RF power splitter 24 RF power supply 26 Wafer 28 Surface area 28b Frost Processing (part) 30 Step processing parts 30a, 30d, 30g Rectangular grooves 30c Concentric grooves 30e Rectangular inclined grooves 30f V-shaped inclined grooves 32 Si substrate 34 Silicon dioxide film 35 Polysilicon film 36 Photoresist film 38 Hole shape 39 Line・ And space shape 42 Aluminum alumite jig 44 Aluminum alumite clamp 52 Aluminum alumite upper electrode 55 Gas blowing hole

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hitoshi Yokokawa 2-3-2 Uchisaiwai-cho, Chiyoda-ku, Tokyo Kawasaki Steel Corporation Tokyo Main Office (72) Ryoichi Kubo 2-2-2 Uchisaiwai-cho, Chiyoda-ku, Tokyo No. Kawasaki Steel Corporation Tokyo Head Office (72) Koji Wakabayashi Inventor 2-3-2 Uchisaiwaicho, Chiyoda-ku, Tokyo Kawasaki Steel Corporation Tokyo Headquarters (72) Inventor Hidetaka Horiuchi 2-2-2 Uchisaiwaicho, Chiyoda-ku, Tokyo No. 3 Kawasaki Steel Corporation Tokyo Head Office

Claims (19)

[Claims] 1. A processing apparatus for performing a process for manufacturing a semiconductor device on an object to be processed mounted in a processing tank, wherein at least a part of components in the processing tank has a substantially vertical step. A processing device having a surface made up of a plurality of small regions divided by a sub-region. 2. The processing apparatus according to claim 1, wherein the plurality of small areas are arranged according to a temperature gradient formed on a surface of the component during operation of the apparatus. 3. The apparatus according to claim 1, wherein an adhering substance is deposited on the surface composed of the plurality of small areas by operation of the apparatus, and the step has a height sufficient to prevent the adhering substance from peeling off. Item 3. The processing device according to item 1 or 2. 4. A deposit is deposited on the surface composed of the plurality of small areas by operation of the apparatus, and the plurality of small areas limits the size of the deposit to prevent the detachment of the deposit. The processing apparatus according to claim 1, wherein the processing apparatus has an appropriate area for the processing. 5. The method according to claim 1, wherein the object to be processed is a wafer, and the processing tank is a tank for performing a dry etching process on a silicon oxide film on the surface of the wafer using a fluorine-based gas. A processing device according to any one of the above. 6. The processing apparatus according to claim 1, wherein said surface is an aluminum surface having an alumite treatment layer. 7. In a processing apparatus for performing processing for manufacturing a semiconductor device, when processing an object to be processed mounted in a processing tank, a deposit on a component in the processing tank is generated by operation of the processing apparatus. Using a processing device in which at least a part of the surface on which is deposited is divided into small areas by a substantially vertical step having a height sufficient to prevent the detachment of the deposits. Method. 8. When a semiconductor device substrate mounted in a processing bath is processed for manufacturing a semiconductor device, at least a part of a surface of a component in the processing bath on which deposits are deposited by the processing is removed. A method of manufacturing a semiconductor device, comprising dividing a film of the attached matter into a plurality of small regions by a step for limiting the size. 9. The plurality of small regions include a plurality of small convex regions and small concave regions divided by the step, and a distance between adjacent small convex regions dividing the film of the attached matter. The method for manufacturing a semiconductor device according to claim 8, wherein the semiconductor device is separated by a distance. 10. The method for manufacturing a semiconductor device according to claim 8, wherein the step has an angle at which the film of the deposit is divided. 11. The method for manufacturing a semiconductor device according to claim 8, wherein said step has a height at which said film of the deposit is divided. 12. The semiconductor device according to claim 8, wherein the step separates the adhesion film deposited during a required cumulative processing time to prevent peeling. Manufacturing method. 13. When a semiconductor device substrate mounted in a processing bath is processed to manufacture a semiconductor device, at least a part of a surface of a component in the processing bath on which deposits are deposited by the processing is removed. A method of manufacturing a semiconductor device, comprising dividing into a plurality of small regions by a substantially vertical step. 14. When a semiconductor device substrate mounted in a processing bath is processed to manufacture a semiconductor device, at least a part of a surface of a component in the processing bath on which deposits are deposited by the processing is removed. A method of manufacturing a semiconductor device, comprising dividing into a plurality of small convex portions by one-dimensional grooves. 15. The deposit is generated in a ring-shaped region on the surface of the component, and the groove is disposed substantially perpendicular to a circumferential direction of the ring-shaped region. A method for manufacturing a semiconductor device according to claim 14. 16. The semiconductor device according to claim 16, wherein the component has an inner edge surrounding the semiconductor device substrate mounted in the processing tank, and the groove is disposed near the inner edge and substantially perpendicular to the inner edge. The method for manufacturing a semiconductor device according to claim 14, wherein: 17. The semiconductor device according to claim 14, wherein said groove is arranged substantially along a temperature gradient formed on a surface of said component during operation of said device. Production method. 18. A component in a processing tank for mounting a semiconductor device substrate to be processed in order to manufacture a semiconductor device, wherein at least a part of the surface is formed into a plurality of small regions by a substantially vertical step. Characterized by being divided,
Components of semiconductor manufacturing equipment. 19. A focus ring for surrounding a semiconductor device substrate to be processed in a plasma processing apparatus for manufacturing a semiconductor device, wherein a plurality of grooves are disposed on a surface near an inner edge of the focus ring so as to be substantially perpendicular to the inner edge. Wherein the focus ring has a region divided into a plurality of small convex regions.