TWI581302B - Plasma processing device - Google Patents

Description

Plasma processing device

The invention relates to a plasma processing device for performing plasma treatment on a large substrate by using plasma.

In the manufacturing process of the FPD (Flat Panel Display), various kinds of plasma treatments such as plasma etching, plasma ashing, and plasma film formation are applied to the glass substrate for FPD. As an apparatus for performing plasma processing thereof, there is known an inductively coupled plasma (ICP) processing apparatus which produces a high-density plasma and performs a desired plasma treatment on a glass substrate by the plasma.

In general, the inductively coupled plasma processing apparatus includes a processing chamber in which a glass substrate is internally sealed and airtight, and a coil-shaped high frequency antenna disposed outside the processing chamber. The processing chamber has a dielectric window formed by a dielectric body that also serves as a top plate portion, and the high frequency antenna is disposed above the dielectric window. The inductively coupled plasma processing apparatus generates an induced electric field in a processing chamber through a dielectric window by applying high-frequency electric power to a high-frequency antenna, and excites a processing gas introduced into the processing chamber by the induced electric field to generate a plasma, and uses the same. The plasma is subjected to a desired plasma treatment of the glass substrate.

Here, if the bottom surface of the dielectric window is exposed to the processing chamber, the bottom surface of the dielectric window is exposed to the plasma and is damaged. For example, it is scratched due to sputtering caused by cations. Since the dielectric window is not easy to handle, it is not easy to replace or clean when damaged. In response to this, the bottom surface of the dielectric window is covered with a dielectric cover made of a dielectric body that can be easily attached and detached (see, for example, Patent Document 1). Thereby, the bottom surface of the dielectric window can be protected from damage to the dielectric window.

However, in recent years, the glass substrate for FPD has been enlarged, and accordingly, the processing chamber has also been enlarged. Therefore, the top portion of the processing chamber, that is, the dielectric window is also enlarged, and the dielectric cover covering the dielectric window is covered. The cover is also enlarged. When the dielectric cover is enlarged, it is difficult to form the dielectric cover by a single component. Therefore, for example, in the inductively coupled plasma processing apparatus for processing the FPD glass substrate after the fourth generation, as shown in FIG. It is to be noted that the dielectric cover 100 is configured by combining a plurality of divided pieces 101. Further, each of the divided pieces 101 supports the bottom surface by the dielectric cover fixtures 102a and 102b, and the dielectric cover fixtures 102a and 102b are fixed to the beam formed of aluminum disposed in the top plate portion of the processing chamber.

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2001-28299

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2010-251708

However, each of the divided pieces 101 receives heat from the plasma to cause thermal expansion. For example, there is a crack at the boundary between the adjacent divided pieces 101, but the dielectric cover holders 102a, 102b are not adjacent to the divided pieces 101. The junction is covered entirely, so when there is a crack at the junction, there will be problems with the dielectric window and the beam being exposed to the plasma and being damaged.

Further, at the boundary between the two divided pieces 101, the reaction product infiltrates and accumulates. When there is a crack at the boundary between the divided pieces 101, the reaction product is peeled off and the particles float in the processing chamber as a deposit. The problem of attaching to a glass substrate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a plasma processing apparatus which can prevent damage to other constituent components covered with a dielectric cover and prevent deposits from adhering to the substrate.

In order to achieve the above object, the plasma processing apparatus according to claim 1 includes a processing chamber that is a processing space for generating plasma, and is disposed opposite to the substrate exposed to the plasma in the processing chamber. Dielectric cover, characterized in that: the dielectric cover is combined with a plurality of points The cutting piece is configured; the boundary between the two adjacent divided pieces is covered by a cover plate; and each of the divided pieces is supported by the cover plate.

The plasma processing apparatus according to claim 2, wherein the plasma processing apparatus according to the first aspect of the invention is characterized in that the gap between the two adjacent divided pieces is a gap having a predetermined width.

The plasma processing apparatus according to claim 3, wherein the cover plate covers 90% of the entire boundary of the adjacent two divided pieces. the above.

The plasma processing apparatus according to any one of claims 1 to 3, further comprising a gas supply unit that supplies a processing gas, the cover plate The gas supply unit and the processing chamber are interposed between the gas supply unit and the processing chamber, and include a gas introduction hole that communicates with the gas supply unit and the processing chamber.

The plasma processing apparatus according to any one of claims 1 to 4, wherein the cover supporting device for supporting the cover plate and the cover plate are the same. Set separately.

The plasma processing apparatus according to any one of claims 1 to 5, wherein each of the divided sheets is a square or rectangular dielectric member. The one side of the dielectric component is at least 500 mm or more.

The plasma processing apparatus according to claim 6, wherein the one of the dielectric members is at least 900 mm or more.

The plasma processing apparatus according to any one of claims 1 to 7, further comprising: a high frequency antenna, wherein the dielectric processing device is related to the dielectric material a cover is disposed on the opposite side of the substrate and high frequency electric power is applied; a dielectric window is disposed between the dielectric cover and the high frequency antenna; and a beam supports the dielectric window; the cover The plate is mounted on the aforementioned beam.

According to the invention, the boundary between two adjacent segments is covered by a cover plate The cover, therefore, even if each of the divided pieces is thermally expanded, so that the boundary between the adjacent two divided pieces is cracked, the other constituent members covered with the dielectric cover are not exposed to the plasma. Thereby, damage to other constituent components can be prevented. Further, the reaction product deposited in the vertical direction or at the boundary between the adjacent two divided pieces is peeled off, and the cover material prevents the reaction product from peeling off from the boundary from scattering, so that deposits due to the reaction product can be prevented from adhering to the substrate. .

Further, since each of the divided pieces is supported by the cover plate, it is not necessary to fix each of the divided pieces by bolts, and even if the divided pieces are thermally expanded, they are not restrained by bolts or the like, so that compression of each divided piece can be prevented. Stress or tensile stress.

Further, since the divided pieces are not fixed to the support beam supporting the dielectric window but supported by the cover plate, the number of divisions and the divided shape can be determined without considering the shape of the support beam.

S‧‧‧Substrate

1‧‧‧ container

2‧‧‧Antenna room

3‧‧‧Processing room

4‧‧‧ dielectric window

5‧‧‧Divided dielectric components

6‧‧‧Support beam

7‧‧‧ hanging parts

8‧‧‧Antenna

9‧‧‧matcher

10‧‧‧ Plasma processing unit

11‧‧‧High frequency power supply

12‧‧‧ Dielectric cover

13‧‧‧Segmentation

14‧‧‧ gas supply device

15‧‧‧ gas introduction path

16‧‧‧ gas flow path

17‧‧‧ Cover

17a‧‧‧Flange

17b‧‧‧Axis

18‧‧‧ gas introduction hole

19‧‧‧ Pedestal

20‧‧‧Insulator frame

21‧‧‧Electrical insulator

22‧‧‧Loading surface

23‧‧‧matcher

23a‧‧‧Electric Rod

24‧‧‧High frequency power supply

25‧‧‧Exhaust device

26‧‧‧Exhaust pipe

27‧‧‧ gap

28‧‧‧ support

28a‧‧‧Flange

28b‧‧‧Axis

29‧‧‧Gas Supply Department

30‧‧‧ gas flow path

31‧‧‧ Hollow

32‧‧‧Bolts

33‧‧‧ head

34‧‧‧ gas supply path

35‧‧‧ gap

36‧‧‧ gap

37‧‧‧ components

38‧‧‧ bolt

39‧‧‧Bolt seat surface

40‧‧‧ gate valve/cover

41‧‧‧Ontology

42‧‧‧Protruding

100‧‧‧ dielectric cover

101‧‧‧Segmentation

102a, 102b‧‧‧ dielectric cover fixture

103‧‧‧ gas introduction hole

104‧‧‧ gas flow path

Fig. 1 is a cross-sectional view schematically showing the configuration of a plasma display device according to an embodiment of the present invention.

Figure 2 is a bottom plan view showing the split pattern of the dielectric window of Figure 1.

Figure 3 is a view showing the dielectric cover of Figure 1 as viewed in the direction of the white arrow.

4A is a cross-sectional view of each portion of the cover plate of FIG. 3, FIG. 4(A) is a cross-sectional view taken along line AA of FIG. 3, and FIG. 4(B) is a cross-sectional view taken along line BB of FIG. 4(C) is a cross-sectional view taken along line CC of FIG. 3, and FIG. 4(D) is a cross-sectional view taken along line DD of FIG.

Fig. 4B: Fig. 4(E) is a cross-sectional view showing a modification of the cover plate of Fig. 4(C).

Fig. 5 is a view showing a positional relationship between a gas flow path and a gas introduction hole in a conventional plasma processing apparatus, Fig. 5(A) shows a case where the split piece does not thermally expand, and Fig. 5(B) shows a case where the split piece is thermally expanded. .

Fig. 6 is a view showing the expansion of each of the cover plates of Fig. 3.

Fig. 7 is a view showing a first modification of each of the cover plates of Fig. 3.

Fig. 8 is a view showing a modification of the method of attaching the support base in Fig. 4(B) to the support beam.

Fig. 9 is a view showing a second modification of each of the cover plates of Fig. 3.

Fig. 10 is a view showing a third modification of each of the cover plates of Fig. 3.

Fig. 11 is a view showing a configuration of a divided piece and a dielectric cover fixture in a conventional plasma processing apparatus.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the plasma processing apparatus of the present embodiment, a plasma processing such as plasma etching, plasma ashing, or plasma film formation is performed on a glass substrate (hereinafter referred to as "substrate") S for FPD. The FPD using the substrate to which the plasma treatment is applied includes a liquid crystal display (LCD), an electroluminescence (EL) display, a plasma display (PDP), and the like.

Fig. 1 is a cross-sectional view schematically showing the configuration of a plasma processing apparatus of the present embodiment.

In FIG. 1, the plasma processing apparatus 10 includes a container 1 and a dielectric window 4 disposed in the container 1 and forming an antenna chamber 2 in the upper space in the container 1 and forming the same The inside of the container 1 is drawn in the processing chamber 3 area of the lower space. In the plasma processing apparatus 10, the dielectric window 4 constitutes the bottom of the antenna chamber 2, and constitutes the top plate portion of the processing chamber 3. The processing chamber 3 is kept airtight and produces an inductively coupled plasma, and the substrate S is subjected to a desired plasma treatment by the inductively coupled plasma.

The container 1 has a rectangular tube shape having an upper portion, a bottom portion, and four side walls joined thereto. Further, the number of the side walls of the container 1 is not limited to four, and may be three or more depending on the constitution of the plasma processing apparatus 10 and the contents of the plasma treatment performed. Further, the container 1 may be a cylindrical container having an upper portion, a bottom portion, and a cylindrical portion connecting the same. The material of the container 1 is an electrical conductor such as aluminum or aluminum alloy, and the container 1 is connected. Ground. When aluminum is used as the material of the container 1, an alumite treatment may be applied to the inner wall surface of the container 1 in order to avoid abnormal discharge from the inner wall surface of the container 1.

The dielectric window 4 is composed of a plate-like member of a dielectric body disposed in parallel with the upper portion or the bottom portion of the container 1, and is divided into a plurality of divided components, such as eight divided dielectric members 5 (see FIG. 2). The thickness of the dielectric window 4 is, for example, 40 mm, and the dielectric system constituting the dielectric window 4 is made of ceramic or quartz such as Al ₂ O ₃ . Moreover, the division type of the dielectric window 4 is not limited to the eight divisions shown in FIG. 2, and the number of divisions and the shape of the division may be determined according to the size of the substrate subjected to the plasma treatment and the content of the plasma treatment, and dielectric The window 4 may also not be divided.

The plasma processing apparatus 10 further includes a support beam 6 as a support assembly for supporting the dielectric window 4. The support beam 6 is, for example, a flat-shaped component made of aluminum, and supports the divided dielectric components 5 from below. The support beam 6 is suspended and supported by a cylindrical suspension member 7 extending from the top plate portion of the container 1 toward the lower side in the drawing, and is disposed, for example, at a slightly central position in the upper and lower directions of the interior of the container 1. Maintain a horizontal state.

The position of the support beam 6 in the up-and-down direction is not limited to a slightly centered portion depending on the structure of the antenna 8 and the structure inside the processing chamber, and may be higher above the center or lower than the center. Further, the shape and arrangement of the suspension member 7 can be appropriately determined depending on the shape and size of the support beam 6 supported by the suspension member 7. The material of the support beam 6 is made of a conductor, such as a metal material such as aluminum. When aluminum is used as the material of the support beam 6, in order to avoid generation of contaminants from the surface, the surface of the support beam 6 is subjected to an alumite treatment. Further, as will be described later, a gas flow path 16 through which the processing gas flows is formed in one portion of the support beam 6.

The plasma processing apparatus 10 further includes a high frequency antenna (hereinafter simply referred to as "antenna") 8 disposed inside the antenna room 2. The antenna 8 is configured such that its outer contour is a substantially square or substantially rectangular planar square spiral shape and is disposed on the top surface of the dielectric window 4. A matching unit 9 and a high-frequency power source 11 are provided outside the container 1, and one end of the antenna 8 is connected to the high-frequency power source 11 via a matching unit 9. The other end of the antenna 8 is attached to the inner wall of the container 1 and is grounded via the container 1.

The plasma processing apparatus 10 further includes a dielectric cover 12 as a "cover" covering the bottom surface of the dielectric window 4. The dielectric cover 12 is composed of a square-shaped or rectangular-shaped plate-like assembly formed of a dielectric material.

The shape of the dielectric cover 12 is preferably square or rectangular. However, due to the structural limitations of the plasma processing apparatus 10 and the like, for example, to avoid interference with the structures and to avoid the structure, the system is partially The outer shape has irregularities, and therefore, the present embodiment is substantially square or substantially rectangular. However, even if it is a substantially square or a substantially rectangular shape, the effect of the present invention is not affected, and therefore, the shape thereof is included, and the present embodiment is called a square or a rectangle. The same applies to the divided piece 13 and the divided dielectric unit 5 which will be described later. Further, the material of the dielectric cover 12 is, for example, ceramic or quartz using Al ₂ O ₃ or the like.

In the present embodiment, the dielectric cover 12 is divided into nine divided pieces 13 differently from the dielectric window 4. Specifically, as shown in FIG. 3, the dielectric cover 12 is configured by a combination of nine divided pieces 13 of 3 × 3 .

In order to minimize the effect of the present invention, the size of the divided piece 13 is not limited. However, the larger the divided piece 13 is, the larger the opening amount of the boundary between the adjacent divided pieces 13 is due to thermal expansion, and the above-mentioned problems are caused. The point will be more obvious. Therefore, the effect of the present invention, such as the effect of preventing damage of other constituent components and the effect of preventing scattering of particles, is significant, if the length of one side of the divided piece 13 is at least 500 mm or more, preferably 800 mm to More than 900mm, it can play a greater role. In the present embodiment, the shape of the divided piece 13 is a square or a rectangle, but the shape of the divided piece 13 is not limited thereto, and may be a triangle or a pentagon according to requirements, or may be formed by combining different shapes. .

Returning to Fig. 1, the plasma processing apparatus 10 includes a gas supply device 14 disposed outside the container 1. The gas supply device 14 is connected to the gas flow path 16 of the support beam 6 via a gas introduction path 15 which is a hollow portion formed inside a part of the suspension member 7. The gas supply device 14 supplies the processing gas for the plasma processing, and when the substrate S is subjected to the plasma treatment, the processing gas passes through the gas introduction path 15, the gas flow path 16 in the support beam 6, and the cover plate 17 which will be described later. The gas introduction hole 18 is supplied into the processing chamber 3. The treatment gas system uses, for example, CF ₄ gas, C ₂ F ₆ gas, SF ₆ gas.

Further, the plasma processing apparatus 10 includes a susceptor 19 that faces the dielectric window 4 in the processing chamber 3 and is disposed on the bottom surface of the processing chamber 3 via the electrical insulator 21, and a housing accommodating the susceptor 19 a body-shaped insulator frame 20; and a gate valve disposed on the side wall of the container 1 so as to face the inside of the processing chamber 3, and to seal and open the opening through which the substrate S is carried into the processing chamber 3 and carried out by the processing chamber 3 40.

The top surface of the susceptor 19 is not covered with the insulator frame 20, but an electrostatic chuck is formed. The electrostatic chuck constitutes a mounting surface 22 on which the substrate S is placed and adsorbed and fixed. The mounting surface 22 is opposed to the dielectric cover 12. The material of the susceptor 19 is a conductor such as aluminum, and the electrostatic chuck is composed of a conductor layer that is an electrostatic electrode that generates electrostatic electricity, and a dielectric layer that is formed on the upper and lower portions by sandwiching the conductor layer.

Further, a matching unit 23 and a high-frequency power source 24 are provided outside the container 1. The susceptor 19 is connected to the matching unit 23 via a current-carrying rod 23a that is inserted into a hole (not shown) on the bottom surface of the processing chamber 3, and is further connected to the high-frequency power source 24 via the matching unit 23. When the substrate S is subjected to plasma processing, the high-frequency power source 24 supplies the high-frequency electric power (for example, high-frequency electric power of 380 kHz) for biasing to the susceptor 19, thereby effectively attracting the ions in the plasma to the carrier. The substrate S on which the surface 22 is placed.

Further, an exhaust device 25 is provided outside the container 1. The exhaust unit 25 is connected to the processing chamber 3 via an exhaust pipe 26 connected to the bottom of the container 1. When the substrate S is subjected to plasma treatment, the exhaust device 25 exhausts the air in the processing chamber 3 to maintain the inside of the processing chamber 3 in a vacuum environment.

In the plasma processing apparatus 10, when the substrate S is subjected to plasma processing, the high frequency power source 11 supplies the antenna 8 with high frequency electric power for generating an induced electric field (for example, high frequency electric power of 13.56 MHz). Thereby, the antenna 8 forms an induced electric field in the processing chamber 3. This induced electric field excites the process gas to produce a plasma.

Figure 3 is a view showing the dielectric cover of Figure 1 as viewed in the direction of the white arrow.

In Fig. 3, as described above, each of the divided pieces 13 is arranged in a ratio of 3 × 3, and at a boundary between the adjacent two divided pieces 13, a predetermined width, for example, a gap of 2 mm to 3 mm in width at room temperature is provided. . Further, on the surface of the dielectric cover 12 on the side of the substrate S (hereinafter referred to as "bottom surface"), a rectangular member having a long side, that is, a plurality of cover plates 17 are disposed corresponding to the respective gaps 27 to cover each Clearance 27. The length of the cover plate 17 is set to be at least 500 mm or more, preferably 800 mm or more, more desirably 900 mm or more, and the width is set to be larger than the width of the gap 27, and is not opposed to the gap 27 in the cover plate 17. The portion of the two divided pieces 13 adjacent to each other by the lower side supporting the gap 27 is the edge portion. That is, each of the cover plates 17 supports the divided pieces 13.

Further, each of the cover plates 17 is attached to the support beam 6 by two support seats 28 (cover support members), and includes a gas flow path 16 provided in the support beam 6 and a gas supply portion 29 to be described later. The gas flow path 30 corresponds to a plurality of gas introduction holes 18.

4(A) to 4(D) are cross-sectional views of portions of the cover plate of Fig. 3, Fig. 4(A) is a cross-sectional view taken along line AA of Fig. 3, and Fig. 4(B) is taken along line 3 A cross-sectional view of the line BB, FIG. 4(C) is a cross-sectional view taken along line CC of FIG. 3, and FIG. 4(D) is a cross-sectional view taken along line DD of FIG.

As shown in FIG. 4(A), the cover plate 17 covers the gap 27 and supports the edge portions of the adjacent two divided pieces 13 from below.

As shown in FIG. 4(B), the support base 28 includes a cover member having a flange T-shaped portion of the flange 28a and the shaft portion 28b, and the cover plate 17 is supported by the flange 28a, and includes a hollow portion. a female threaded portion (not shown) formed on the inner side surface of the shaft portion 28b of the shaft 31, and a screw portion 32 of the bolt 32 of the bottom surface of the support beam 6 formed by the male thread portion (not shown) formed on the side surface of the head portion 33, The cover plate 17 is attached to the support beam 6.

Further, a gap 35 having a predetermined width, for example, a width of 2 mm to 3 mm at room temperature, is provided between the shaft portion 28b and each of the divided pieces 13. Thereby, even if each point Since the cut piece 13 is thermally expanded and does not come into contact with the shaft portion 28b, it is possible to reliably prevent the compressive stress from being generated in each of the divided pieces 13 or the shaft portion 28b.

As shown in FIG. 4(C), the support beam 6 is formed at a portion where the gas flow path 16 is formed inside, and the cover 17 is provided through the cover 17 and communicates with the gas flow path 16 and the processing chamber 3. A plurality of gas introduction holes 18 are provided. Further, as shown in FIG. 4(D), at a portion where the support beam 6 does not exist, the gas supply portion 29 is provided by the divided dielectric member 5, and the gas flow path 30 is formed inside the gas supply portion 29. A gas supply path 34 branched from the hanger 7 including the gas introduction path 15 is connected to the gas supply unit 29.

In Fig. 4(C) and Fig. 4(D), the cover plate 17 is composed of a member having a T-shaped cross section including a flange 17a and a shaft portion 17b, and the flange 17a supports the divided pieces 13 from below. In the edge portion, the shaft portion 17b penetrates between the two divided pieces 13 and reaches the support beam 6 and the gas supply portion 29. Since each of the gas introduction holes 18 penetrates the shaft portion 17b, the gas flow path 30 and the inside of the processing chamber 3 communicate with each other.

Further, a gap 36 having a predetermined width, for example, a width of 2 mm to 3 mm at room temperature, is provided between the shaft portion 17b and each of the divided pieces 13. Thereby, even if each of the divided pieces 13 is thermally expanded, it does not come into contact with the shaft portion 17b. Therefore, it is possible to reliably prevent the compressive stress from being generated in each of the divided pieces 13 or the shaft portion 17b.

Further, the cross-sectional shape of the cover plate 17 is not limited to a T-shape, and as shown in FIG. 4(E), the top surface may be flat. At this time, the support beam 6 protrudes downward and comes into contact with the top surface of the cover plate 17.

However, in the conventional plasma processing apparatus shown in FIG. 11, since there is no cover plate 17, it is necessary to cover the gas flow path of the support beam or the gas supply portion with the divided piece of the dielectric cover, as shown in FIG. 5(A). The separator 101 is provided with a gas introduction hole 103 that allows the gas flow path 104 to communicate with the processing chamber.

However, since the divided piece 101 is a square-shaped or rectangular plate-like member having a length of at least 500 mm on one side, when the divided piece 101 receives heat from the plasma and thermally expands, it spreads over the entire circumference. Usually, since the gas introduction hole 103 is provided at the peripheral portion of the divided piece 101, the gas introduction hole The position of 103 is greatly shifted. As shown in Fig. 5(B), a part of the gas introduction holes 103 are not opposed to the gas flow path 104, and as a result, the communication between the gas flow path 104 and the processing chamber is hindered. Further, since the diameter of the gas introduction hole 103 is at most φ 0.5 mm to 1 mm, the gas introduction hole 103 is not easily cut by the divided piece 101 made of ceramics or the like, and even if there is only one, the gas introduction hole 103 is processed. In the case of a bad situation, the split piece 101 becomes a defective product. Further, since the divided piece 101 has a length of at least 500 mm as described above, when the divided piece 101 becomes a defective product, the efficiency is extremely poor from the viewpoint of material saving. Further, in FIG. 11, the dielectric cover 100 is divided into four, but even if the size of the divided piece 101 is reduced by, for example, dividing the dielectric cover 100 into nine parts, the gas introduction hole 103 is difficult to be opened. It has not changed, so the frequency of defects has hardly changed, and the material savings have not been expected to be greatly improved.

On the other hand, in the plasma processing apparatus 10 of the present embodiment, the gas introduction hole 18 is provided not in the split piece 13 but on the cover plate 17. The width of the cover plate 17 is much smaller than the length of one side of the split piece 101, and even if the cover plate 17 is thermally expanded, the cover plate 17 does not stretch as much as in the width direction, as shown in Figs. 4(C) and 4(D). In the cross section, only the gas introduction hole 18 moves in the width direction. Therefore, in the plasma processing apparatus 10, the communication between the gas flow paths 16, 30 and the processing chamber 3 is not hindered by the fixed position of the cover plate 17. Further, the vertical or gas introduction hole 18 causes a machining failure, and the cover plate 17 becomes a defective product. Since the cover plate 17 is smaller than the divided piece 101, there is no problem in terms of material saving.

The thickness of each of the cover plates 17 is preferably small, and is preferably set to be 5 mm or less. Thereby, since the cover plate 17 does not protrude into the processing chamber 3, there is no case where the cover plate 17 becomes the starting point of abnormal discharge. Further, for the same reason, the edge portion of the cover plate 17 is chamfered and does not become a ridge portion or is formed in a circular shape. Furthermore, the cover plate 17 can also be made entirely round.

Further, the divided piece 13 constituting the dielectric cover 12 is made of a dielectric material such as ceramic such as Al ₂ O ₃ or ZrO ₂ or quartz, or a dielectric material such as Y ₂ O ₃ flame-sprayed on a predetermined core material. Or an electrical conductor (such as an aluminized surface treated with an aluminum surface).

According to the plasma processing apparatus 10 of the present embodiment, the gap 27 provided at the boundary between the adjacent two divided pieces 13 is covered by the cover plate 17, and therefore, even if the divided pieces 13 are thermally expanded, the gap 27 is opened. The cover plate 17 will still cover the gap 27, and the dielectric window 4 and the support beam 6 will not be exposed to the plasma. Thereby, it is possible to prevent the dielectric window 4 or the support beam 6 from being damaged by the plasma. Further, since the cover product 17 is covered with the cover plate, the reaction product which is a cause of the deposit is less likely to accumulate in the gap 27, and further, for example, even if the reaction product is deposited in the gap 27, the cover plate 17 covers the gap 27. Since the reaction product which is peeled off by the gap 27 is prevented from scattering, it is possible to prevent the deposit due to the reaction product from adhering to the substrate S.

In the above-described plasma processing apparatus 10, since the gap 27 has a predetermined width, even if the adjacent two divided pieces 13 are thermally expanded, they do not touch each other, whereby the compression of each divided piece 13 can be surely prevented. stress.

Further, since each of the divided pieces 13 is supported by the cover plate 17, it is not necessary to fix the divided pieces 13 by bolts or the like, and even if the divided pieces 13 are thermally expanded, they are not restrained by bolts or the like, and can be prevented. Compressive stress and tensile stress are generated in each of the divided pieces 13.

Further, the support base 28 for mounting the cover plate 17 is provided separately from the cover plate 17, and since the flange of the support base 28 supports the cover plate 17, the cover plate 17 does not need to be fixed by bolts or the like, and can be prevented from being applied to the cover plate 17. Compressive stress and tensile stress are generated.

Although the present invention has been described above using the above embodiments, the present invention is not limited to the foregoing embodiments.

As shown in FIG. 6, each of the cover plates 17 is formed of a rectangular component having a long side, but the shape of the cover plate is not limited thereto, and each of the cover plates 17 may be constituted by a well-shaped component joined to each other. Alternatively, as shown in Fig. 7, each of the cover plates is formed by a substantially cross-shaped assembly 37, and each of the components 37 may be used in combination.

The support base 28 is attached to the support beam 6 by fitting with the head 33 of the bolt 32 screwed to the bottom surface of the support beam 6, but the method of attaching the support base 28 to the support beam 6 is not limited thereto. As shown in FIG. 8, the bolt seat surface 39 can also be disposed in the support beam 6 by the reaming process above the support beam 6, and the support beam 6 and the support base 28 can be simultaneously locked by the bolts 38. 28 is mounted to the support beam 6.

Further, in the above-described embodiment, the case where each of the divided pieces 13 is square or rectangular is described. However, since the position of the gap 27 between the divided pieces 13 is not limited to the position of the support beam 6, the shape of each divided piece 13 is It may also be a triangle or a pentagon, or more polygons, and may also be an irregular shape in response to the setting environment of each of the divided pieces.

Further, in the above-described embodiment, each of the cover plates 17 covers all the gaps 27. However, if it is not easy to completely cover all the gaps 27 depending on processing accuracy and structural reasons, it is not substantially covered. The part which causes a problem, as shown in Fig. 9, is also in the vicinity of the side wall of the container 1, and the gap 27 may be exposed. Since a part of the gap 27 near the side wall of the container 1 is opposed only to the bottom of the container 1 in which the susceptor 19 is not present, the reaction product is generated when a part of the gap 27 is scattered by the gap 27 and falls by gravity. The object will only fall to the bottom of the container 1 without reaching the substrate S placed on the mounting surface 22 of the susceptor 19. Further, since one of the gaps 27 is separated from the mounting surface 22 of the susceptor 19, even if the scattered reaction product is transported by gas, it is difficult to reach the substrate S. Further, when each of the cover plates 17 covers at least 90% of all the gaps 27, the amount of scattering of the reaction product from the gaps 27 can be reduced, and the deposits generated by the reaction products hardly adhere to the substrate. Therefore, each of the cover plates 17 should cover at least 90% of all the gaps 27.

In the above-described Patent Document 2, since the dielectric cover fixtures 102a and 102b fixed to the beam are supported by the respective divided pieces 101 to support the divided pieces 101, the position of the boundary between the divided pieces 101 needs to be The arrangement of the beams is the same, but in the foregoing plasma processing apparatus 10, the support is installed on the support beam 6. The support 28 does not directly support the split piece 13 , and the split piece 13 is supported by the cover plate 17 , and the cover plate 17 is disposed at the boundary between the split pieces 13 , so that the split pieces 13 are not necessarily required. The location of the junction needs to coincide with the configuration of the support beam 6.

In the above-described embodiment, the case where the dielectric window 4 is divided into 8 parts and the dielectric cover 12 divided into 9 parts is described, that is, the division of the dielectric window 4 and the dielectric cover 12 is described. The number is different, but for example, the number of divisions of the dielectric window 4 and the dielectric cover 12 is also 9. In this case, the boundary between the divided pieces 13 and the arrangement of the support beams 6 can be made uniform. On the other hand, as shown in Fig. 10, the position of the gap 27 provided at the boundary between the divided pieces 13 may be offset from the arrangement of the support beams 6 (shown by broken lines in the figure). At this time, in each of the cover plates 40, a protruding portion 42 protruding from the main body 41 is provided along the bottom surface of the dielectric cover 12, and by supporting the protruding portion 42 with the support base 28, the cover plate can be made The body 41 of the 40 is offset from the position of the support base 28 (the arrangement of the support beams 6), whereby the body 41 of the cover 40 can cover the gaps 27 and support the divided pieces 13.

Further, it is needless to say that the number of divisions of the dielectric cover 12 and the shape of the divided piece 13 are not limited to the number of divisions and shapes in the above-described embodiment, and the number of divisions and the shape of the divided piece can be changed as needed.

12‧‧‧ Dielectric cover

13‧‧‧Segmentation

17‧‧‧ Cover

18‧‧‧ gas introduction hole

27‧‧‧ gap

28‧‧‧ support

Claims (5)

A plasma processing apparatus includes a processing chamber that is a processing space for generating plasma, and a dielectric cover that is disposed opposite to a substrate exposed to the plasma in the processing chamber, wherein the dielectric is The cover is composed of a plurality of divided pieces; the boundary between the two adjacent divided pieces is covered by a cover plate; and each of the divided pieces is supported by the lower cover by the lower side; The boundary of the sheet is provided with a gap of a predetermined width; the cover plate covers more than 90% of the entire boundary of the adjacent two divided sheets; and the cover support for supporting the cover is separately provided from the cover. The plasma processing apparatus according to claim 1, further comprising a gas supply unit that supplies a processing gas; the cover plate is interposed between the gas supply unit and the processing chamber, and includes a gas that communicates with the gas a gas introduction hole of the supply unit and the processing chamber. The plasma processing apparatus according to claim 1, wherein each of the divided sheets is composed of a square or rectangular dielectric member, and one of the dielectric members is at least 500 mm or more. The plasma processing apparatus according to claim 3, wherein one of the dielectric members is at least 900 mm or more. The plasma processing apparatus according to claim 1, further comprising: a high frequency antenna disposed on a side opposite to the substrate and having high frequency electric power applied to the dielectric cover; The window is disposed between the dielectric cover and the high frequency antenna; and the beam supports the dielectric window; the cover is mounted on the beam.