TWI637660B - Plasma processing device - Google Patents

Abstract

In the plasma processing device, the penetration of the processing container is prevented Local plasma generation at the mouth.

The bottom surface of the opening of the through opening of the processing container is An insulating member (45) is provided as an impedance adjusting member. The insulating member (45) is made of a material having a dielectric constant of 10 or less, more preferably 4 or less. With the insulating member (45), the electrical impedance of the through-opening portion viewed from the plasma can be greater than The sleeve (60) of the body container (2A) prevents the generation of localized plasma in the gate opening (41). The insulating member (45) is provided with a cover member (47) to cover the surface of the insulating member (45) to protect the insulating member (45) from damage caused by plasma.

Description

Plasma processing device

The present invention relates to a plasma processing apparatus for performing substrate processing using a plasma.

In the manufacturing process of a flat panel display typified by a liquid crystal display (LCD), various processes such as a film forming process and an etching process are performed on a substrate. As a substrate processing apparatus which performs these processes, a plasma processing apparatus is known.

The plasma processing apparatus generates a plasma of a processing gas in a processing container and performs substrate processing. At this time, there is a possibility that the inner surface of a processing container made of metal such as aluminum is consumed due to the action of plasma or corrosive gas. Therefore, an anodizing treatment (acid-resistant aluminum treatment) is applied to a processing container made of aluminum, for example.

In addition, in order to prevent damage to the processing container body or generation of localized plasma, a method of providing a protective member inside the processing container is also performed. For example, in Patent Document 1, it is proposed that a gate wall for loading and unloading a substrate be provided with a quartz wall to suppress the occurrence of localized plasma or the deviation of the plasma in the gate opening, and realize in-plane substrate Dealt with Uniformity. Patent Document 1 increases the electrical impedance of the gate opening as viewed from the plasma by increasing the thickness of the quartz-made wall provided at the gate opening compared to other parts in the processing vessel. .

On the other hand, Patent Document 2 proposes that a porous or mesh-shaped conductive electromagnetic wave shield is provided in a pressure detecting opening in a processing container to suppress electromagnetic wave noise superimposed on a pressure signal.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2007-103697 (Scope of patent application, etc.)

[Patent Document 2] Japanese Patent Laid-Open No. 6-29247 (Figure 6 and the like)

In recent years, there has been a strong demand for an increase in the size of a substrate for FPD, and a large substrate having a side of more than 2 m is sometimes used as a processing object. Corresponding to the increase in the size of the substrate, the processing container is also increased in size, and the gate opening is also enlarged. As proposed in Patent Document 1, in a method of increasing the thickness of a quartz wall provided at a gate opening portion to ensure insulation, it is necessary to increase the gate opening in order to secure a sufficient clearance for the substrate to pass safely The height of the portion is only a thickness portion of the quartz wall. However, when the gate opening is enlarged, the gate valve used to open and close the gate opening must be enlarged. Again, when increasing When the gate is opened, the compressive strength of the processing container also decreases. Therefore, it is required to reliably prevent the occurrence of localized plasma in the gate opening while suppressing the size (height) of the gate opening as much as possible.

In addition, the generation of localized plasma in the gate openings tends to be particularly likely to occur when a large bias voltage is applied to a mounting table on which a substrate is placed. Therefore, it is required to prevent the generation of localized plasma in the gate opening in a plasma processing apparatus that applies a large bias voltage to the mounting table.

The object of the present invention is to prevent the generation of a localized plasma in a through-opening portion of a processing container in a plasma processing apparatus.

The plasma processing apparatus of the present invention is a plasma processing apparatus that generates a plasma inside a processing container and processes a substrate. In the plasma processing apparatus of the present invention, the processing container includes a wall forming a through-opening portion, and the through-opening portion has an opening bottom surface, an opening ceiling surface, and two opening side surfaces facing each other. Moreover, the plasma processing apparatus of the present invention is provided with an impedance adjusting member that adjusts the electrical impedance of the through-opening portion at least on the bottom surface of the opening.

In the plasma processing apparatus of the present invention, the through-opening portion may be a gate opening portion for carrying in and out the substrate.

In the plasma processing apparatus of the present invention, the impedance adjusting member may be made of a material having a dielectric constant of 10 or less.

In the plasma processing apparatus of the present invention, the aforementioned impedance adjustment The member may be made of a material having a dielectric constant of 4 or less.

In the plasma processing apparatus of the present invention, the impedance adjusting member may be formed in a sheet shape from a resin material having a dielectric constant of 4 or less.

In the plasma processing apparatus of the present invention, the impedance adjusting member may be a sheet made of polytetrafluoroethylene.

The plasma processing apparatus of the present invention may be further provided with a cover member made of a dielectric on the impedance adjusting member.

The plasma processing apparatus of the present invention is that the impedance adjusting member is the same as the cover member, or may be composed of a material having a dielectric constant smaller than that of the cover member.

The plasma processing apparatus of the present invention is also a cover member made of ceramic.

The plasma processing apparatus of the present invention may further include an insulating protective member that protects the inner wall surface from the plasma along the inner wall surface of the processing container. In this case, the electrical impedance of the through-opening portion viewed from the plasma may be higher than the protective member by the impedance adjusting member. Specifically, with respect to the electrical impedance of the protective member, the electrical impedance of the impedance adjusting member may also be greater than 8Ω.

The plasma processing apparatus of the present invention can also form an insulating protective film on the inner wall surface of the processing container to protect the inner wall surface from the plasma. In this case, the electrical impedance of the through-opening portion viewed from the plasma may be higher than the protective film by the impedance adjusting member. Specifically, with respect to the electrical impedance of the insulating protective film, The impedance of the impedance adjusting member may be greater than 8Ω.

In the plasma processing apparatus of the present invention, the processing container is made of aluminum, and the insulating protective film may be made of an acid-resistant aluminum film.

The plasma processing apparatus of the present invention may further include an observation opening as the through opening for observing the inside of the processing container from the outside. In this case, an end portion on the inner side of the processing container of the observation opening portion may be provided with an electromagnetic wave shielding plate. The electromagnetic wave shielding plate includes a plurality of shielding plates for shielding electromagnetic waves from entering the observation opening portion. Each hole is made of conductive material.

According to the plasma processing apparatus of the present invention, it is possible to effectively prevent the generation of localized plasma in the gate opening portion by the impedance adjusting member.

1‧‧‧ Inductively coupled plasma processing device

2A‧‧‧Body Container

2B‧‧‧ Upper container

4‧‧‧ Antenna Room

5‧‧‧ treatment room

6‧‧‧ Dielectric Wall

7‧‧‧ cover member

8‧‧‧ boom

13‧‧‧ Antenna

14‧‧‧ Matcher

15‧‧‧High-frequency power

16‧‧‧ support beam

20‧‧‧Gas supply device

21‧‧‧Gas supply pipe

22‧‧‧ base

22A‧‧‧mounting surface

24‧‧‧ insulator frame

25‧‧‧ Pillar

26‧‧‧ Bellows

28‧‧‧ Matcher

29‧‧‧High Frequency Power

30‧‧‧Exhaust

31‧‧‧Exhaust pipe

41‧‧‧Gate opening

43‧‧‧observation opening

45‧‧‧Insulating member

47‧‧‧ cover member

50‧‧‧Gate Valve

60‧‧‧ Bushing

S‧‧‧ substrate

[FIG. 1] A cross-sectional view schematically showing a configuration of an inductively coupled plasma processing apparatus according to an embodiment of the present invention.

[Fig. 2] A perspective view showing the structure of two side walls of the body container viewed from the inside of the inductively coupled plasma processing apparatus of Fig. 1. [Fig.

3 is an enlarged cross-sectional view showing the periphery of a gate opening on a side wall of the main body container.

[Fig. 4] In a first modified example, a cross-sectional view around a gate opening of a side wall of a main body container is enlarged.

[Fig. 5] An enlarged front view showing the periphery of the observation opening on the side wall of the main body container.

[Fig. 6] An enlarged cross-sectional view showing the periphery of the observation opening on the side wall of the main body container.

[FIG. 7] In a second modified example, a cross-sectional view around an opening for observation of a side wall of a main body container is enlarged.

Hereinafter, a plasma processing apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing a configuration of an inductively coupled plasma processing apparatus 1 according to an embodiment of the present invention. In the following description, the induction coupling plasma processing apparatus is used as an example, but the present invention is similarly applicable to any plasma processing apparatus.

The inductively coupled plasma processing apparatus 1 shown in FIG. 1 is a plasma etching process for a glass substrate for FPD (hereinafter referred to as "substrate") S, for example. Examples of the FPD include a liquid crystal display (LCD: Liquid Crystal Display), an electroluminescence (EL: Electro Luminescence) display, and a plasma display panel (PDP: Plasma Display Panel).

The inductively coupled plasma processing apparatus 1 includes a processing container 2 including a main container 2A and an upper container 2B.

<Body container>

The main body container 2A is a rectangular container having a bottom wall 2b and four side walls 2c. The main body container 2A may be a cylindrical container. As a material of the main body container 2A, a conductive material such as aluminum or an aluminum alloy is used. When aluminum is used as the material of the main body container 2A, an acid-resistant aluminum treatment (anodic oxidation treatment) is applied to the inner wall surface of the main body container 2A in order to avoid generation of contaminants from the inner wall surface of the main body container 2A. The main body container 2A is in a grounded state. A plurality of through openings are formed in the main body container 2A. The structure of these through openings will be described later.

<Upper container>

The upper container 2B is provided with: a top plate portion 2a; a dielectric wall 6 disposed on the upper portion of the main body container 2A, and partitioning the space in the processing container 2 into two spaces above and below; As a support member that supports the dielectric wall 6.

An antenna chamber 4 is formed in the upper container 2B, and a processing chamber 5 is formed in the main body container 2A. These two spaces are separated by a dielectric wall 6. That is, the antenna chamber 4 is a space formed above the dielectric wall 6 in the processing container 2, and the processing chamber 5 is a space formed below the dielectric wall 6 in the processing container 2. Therefore, the dielectric wall 6 constitutes the bottom of the antenna chamber 4 and constitutes the top plate portion of the processing chamber 5. The processing chamber 5 is held air-tightly, and the substrate S is subjected to plasma processing.

The dielectric wall 6 is formed in a plate shape having a substantially square shape or a substantially rectangular upper and lower surfaces and four side surfaces. The thickness of the dielectric wall 6 is, for example, 30 mm. The dielectric wall 6 is formed of a dielectric material. As the material of the dielectric wall 6, ceramics such as Al ₂ O ₃ or quartz are used. The dielectric wall 6 may be divided into a plurality of parts, for example, four parts.

The lid member 7 is provided at a lower portion of the upper container 2B. The lid member 7 is disposed so as to face the upper end of the main body container 2A. The cover member 7 closes the processing container 2 so as to be disposed on the main body container 2A, and opens the processing container 2 by being separated from the main body container 2A. The lid member 7 may be integrated with the upper container 2B.

The support beam 16 is formed in, for example, a cross shape, and the dielectric wall 6 is supported by the cover member 7 and the support beam 16.

The inductively coupled plasma processing apparatus 1 further includes a plurality of cylindrical suspension rods 8, and the plurality of cylindrical suspension rods 8 each have an upper end portion connected to the top plate portion 2 a of the upper container 2B. . Although three booms 8 are shown in FIG. 1, the number of the booms 8 is arbitrary. The support beam 16 is connected to the lower end of the boom 8. In this way, the support beam 16 is configured to be suspended by a plurality of booms 8 from the top plate portion 2a of the upper container 2B, while maintaining a horizontal state at a substantially central position in the up-down direction inside the processing container 2.

The support beam 16 is formed with a gas flow path (not shown) and a process gas is supplied from a gas supply device 20 described later; and a plurality of openings (not shown) are used to discharge the processing supplied to the gas flow path. gas. As a material of the support beam 16, a conductive material is used. As the The conductive material is preferably a metal material such as aluminum. When aluminum is used as the material of the support beam 16, an acid-resistant aluminum treatment (anodic oxidation treatment) is applied to the inside and outside surfaces of the support beam 16 to avoid generation of contaminants from the surface.

<Gas supply device>

A gas supply device 20 is further provided outside the main body container 2A. The gas supply device 20 is, for example, connected to a gas flow path (not shown) of the support beam 16 via a gas supply pipe 21 inserted into a hollow portion of the central boom 8. The gas supply device 20 is used to supply a processing gas used for plasma processing. During the plasma processing, the processing gas is supplied into the processing chamber 5 through the gas flow path and the openings in the gas supply pipe 21 and the support beam 16. As the processing gas, for example, SF ₆ gas is used.

<First high-frequency supply unit>

The inductively coupled plasma processing device 1 further includes a high-frequency antenna (hereinafter referred to as "antenna") 13 which is disposed inside the antenna chamber 4, that is, disposed outside the processing chamber 5 and having a dielectric wall 6. Up. The antenna 13 has, for example, a substantially square planar square vortex shape. The antenna 13 is disposed above the dielectric wall 6.

A matching device 14 and a high-frequency power source 15 are provided outside the processing container 2. One end of the antenna 13 is connected to a high-frequency power source 15 via a matching device 14. The other end of the antenna 13 is connected to the inner wall of the upper container 2B, and is grounded via the main body container 2A. When the substrate S is subjected to a plasma treatment, a high frequency for forming an induced electric field is supplied to the antenna 13 from the high-frequency power source 15. High frequency power (such as high frequency power at 13.56MHz). Thereby, an induced electric field is formed in the processing chamber 5 by the antenna 13. This induced electric field converts the processing gas into a plasma.

<Mounting table>

The inductively coupled plasma processing apparatus 1 further includes a base (mounting table) 22 on which a substrate S is mounted, an insulator frame 24, a pillar 25, and a corrugated tube 26. The pillar 25 is connected to a lifting device (not shown) provided below the main body container 2A, and protrudes into the processing chamber 5 through an opening 2b1 formed in the bottom wall 2b of the main body container 2A. The pillar 25 has a hollow portion. The insulator frame 24 is provided on the pillar 25. The insulator frame 24 is formed in a box shape with an opened upper portion. An opening is formed on the bottom of the insulator frame 24 to be continued to the hollow portion of the pillar 25. The bellows 26 surrounds the pillar 25 and is air-tightly connected to the insulator frame 24 and the inner wall of the bottom wall 2b of the main body container 2A. Thereby, the airtightness of the processing chamber 5 is maintained.

The base 22 is housed in an insulator frame 24. The base 22 has a mounting surface 22A for mounting the substrate S. As the material of the base 22, a conductive material such as aluminum is used. When aluminum is used as the material of the susceptor 22, an acid-resistant aluminum treatment (anodic oxidation treatment) is applied to the surface of the susceptor 22 to avoid generation of contaminants from the surface.

<Second high-frequency supply unit>

A matching unit 28 and a high-frequency power source 29 are further provided outside the processing container 2. The base 22 is inserted through the opening of the insulator frame 24 and The energizing rod in the hollow portion of the pillar 25 is connected to the matching device 28, and further connected to the high-frequency power source 29 via the matching device 28. When plasma processing is performed on the substrate S, high-frequency power for bias (for example, high-frequency power of 380 kHz) is supplied from the high-frequency power source 29 to the base 22. This high-frequency power is used by the user to effectively pull ions in the plasma into the substrate S placed on the base 22.

<Exhaust device>

A plurality of exhaust devices 30 are further provided outside the processing container 2. The exhaust device 30 is connected to the processing chamber 5 through an exhaust pipe 31 connected to an exhaust port 2b2. The exhaust port 2b2 is formed at a plurality of locations on the bottom wall 2b of the main body container 2A. When plasma processing is performed on the substrate S, the exhaust device 30 exhausts the air in the processing chamber 5 and maintains the inside of the processing chamber 5 in a vacuum or reduced pressure environment.

<Through openings>

FIG. 2 is a perspective view showing the structure of two side walls 2c of the main body container 2A as viewed from the inside of the inductively coupled plasma processing apparatus 1 of FIG. 1. FIG. In addition, for convenience of explanation, in FIG. 2, illustrations of the insulating member 45, the cover member 47, and the electromagnetic wave shielding plate 49 described later are omitted. A gate opening 41 is formed on one side wall 2c of the main body container 2A as a through opening. The gate opening portion 41 is formed in a horizontally long shape and has a width that is larger than the width of the substrate S so that it can pass through the substrate S. The gate electrode opening portion 41 has an opening bottom surface 41a and an opening ceiling surface 41b facing each other. The two opening side surfaces 41c serve as a wall surface for separating the through opening.

The other side wall 2 c of the main body container 2A is formed with an observation opening portion 43 as a through-opening portion different from the gate opening portion 41. The observation opening portion 43 has an opening bottom surface 43a, an opening ceiling surface 43b, and two opening side surfaces 43c which face each other, as a wall surface for partitioning the opening.

<Gate valve>

The gate valve 50 is provided outside the side wall 2c of the main body container 2A. The gate valve 50 has a function of opening and closing the gate electrode opening portion 41 by a driving portion (not shown). The gate valve 50 hermetically seals the gate opening 41 in a closed state. Therefore, the gate valve 50 can maintain the airtightness of the processing chamber 5 in the closed state, and transfer the substrate S between the processing chamber 5 and the outside in the open state.

<Bushing>

Inside the four side walls 2c of the main body container 2A, a bushing 60 is provided along the inner wall surface of each side wall 2c as an insulating protective member covering the inner wall surface and protecting it from the plasma. The bushing 60 is formed of a material such as quartz, aluminum that has been treated with acid-resistant aluminum, and the like. The bushing 60 provided on the side wall 2 c where the gate opening portion 41 is formed has an opening corresponding to the gate opening portion 41. The bushing 60 provided on the side wall 2 c where the observation opening portion 43 is formed has an opening corresponding to the observation opening portion 43.

In addition, in the inductively coupled plasma processing apparatus 1 of the present embodiment, a bushing 60 is also installed on the opening ceiling surface 41b of the gate opening 41 so as to cover the opening ceiling surface 41b.

<Impedance adjustment member>

Next, the impedance adjustment member provided in the gate opening portion 41 will be described in detail with reference to FIG. 3. FIG. 3 is a cross-sectional view of a main part of the side wall 2 c including the gate valve 50 and the gate opening 41. An insulating member 45 serving as an impedance adjusting member is disposed on the opening bottom surface 41 a of the gate opening 41. The insulating member 45 can be provided in a plate-like or sheet-like form, for example.

The insulating member 45 is made of a material having a dielectric constant of 10 or less, preferably 4 or less. Here, examples of the material constituting the insulating member 45 include ceramics such as alumina (dielectric constant 10), quartz (dielectric constant 4), polytetrafluoroethylene (dielectric constant 2), and polycarbonate. (Dielectric constant 3) and the like. Among these materials, it is preferable to use a resin sheet having a heat-resistant material such as polytetrafluoroethylene as the insulating member 45.

By providing an insulating member 45 in the gate opening portion 41, the electrical impedance of the gate opening portion 41 as viewed from the plasma can be increased (to be precise, the gate opening portion 41 is provided with insulation). The electrical impedance of the wall surface of the member 45 is the same below), so as to prevent the occurrence of abnormal discharge or localized plasma. That is, since the electrical impedance of the gate opening portion 41 viewed from the plasma can be made larger than the bushing 60 of the main body container 2A by the insulating member 45, it becomes difficult for the plasma current to flow to the gate opening portion 41 ,From It can prevent the occurrence of abnormal discharge or local plasma.

The insulating member 45 only needs to be provided on at least the opening bottom surface 41 a of the gate opening 41. Although the insulating member 45 may be provided on the opening side surface 41c and / or the opening ceiling surface 41b, it is provided only on the opening bottom surface of the gate opening portion 41 from the viewpoint of ensuring a gap when the substrate S passes through the gate opening portion 41. 41a is preferred. From the viewpoint of preventing particles from adhering to the substrate S, it is also preferable that the insulating member 45 is provided only on the opening bottom surface 41 a of the gate opening 41. When the insulating member 45 is also provided on the opening side surface 41c and / or the opening ceiling surface 41b, the electrical impedance of the gate opening portion 41 becomes too high, and it is difficult for these portions to have a bias voltage to be supplied to the base 22 The function of the counter electrode of electricity. As a result, the sputtering force toward the opening side surface 41c and / or the opening ceiling surface 41b may be weakened, which may cause deposits to be easily deposited during the plasma treatment, and the deposited deposits may be peeled off and become a cause of particles. Therefore, from the viewpoint of suppressing particles, it is preferable that the insulating member 45 is also provided only on the opening bottom surface 41 a of the gate opening portion 41.

The insulating member 45 is not limited to a single member, and may be divided into a plurality of sections. In addition, the insulating member 45 is not limited to a single layer, and a plurality of layers may be arranged in an overlapping manner. In this case, a different material may be used as the insulating member 45 of each layer.

The thickness of the insulating member 45 is to sufficiently secure the gap with the substrate S passing through the gate opening 41 while increasing the electrical impedance of the gate opening 41 as viewed from the plasma and preventing the generation of localized plasma. For example, it is preferably set to 10 mm or less, and set to 2 mm or more. A range of 10 mm or less is more preferable. As an example, when using a polytetrafluoroethylene resin sheet with a dielectric constant of 2 as the insulating member 45, as long as the thickness is 2 mm or more, the insulating member 45 in the gate opening 41 viewed from the plasma can be made. The electrical impedance is more than 8Ω larger than the bushing 60 of the main body container 2A. Furthermore, it has been confirmed that if the difference in electrical impedance between the insulating member 45 in the gate opening portion 41 observed from the plasma and the bushing 60 of the main body container 2A is 8 Ω or more, the gate opening portion 41 can be reliably prevented Abnormal discharge or local plasma generation. When the insulating member 45 is provided in a plurality of layers, it is preferable that the total thickness of the plurality of layers is within the above range.

<Cover member>

As shown in FIG. 3, the inductively coupled plasma processing apparatus 1 of this embodiment is preferably provided with a cover member 47 on the insulating member 45 as an impedance adjusting member. By laminating the insulating member 45 and providing a cover member 47 to cover the surface of the insulating member 45, the insulating member 45 can be protected from damage caused by plasma.

The cover member 47 is preferably formed of a material having plasma resistance. Examples of the material of the cover member 47 include ceramics such as alumina (Al ₂ O ₃ ; dielectric constant 10), aluminum (dielectric constant 10) treated with acid-resistant aluminum, and quartz (dielectric constant 4). A yttrium trioxide sprayed film covers a coating on the surface of the aluminum substrate (dielectric coefficient 11) and the like. Even among these materials, the cover member 47 is preferably formed of a plate material such as an alumina plate or the like having a dielectric constant of about 10.

The thickness of the cover member 47 is to ensure a sufficient gap between the cover member 47 and the substrate S passing through the gate opening 41 while protecting the insulating member 45 from the plasma. For example, the thickness of the cover member 47 is preferably 20 mm or less and 10 mm or more and 20 mm or less. The range below is more preferable.

In the inductively coupled plasma processing apparatus 1 of this embodiment, the insulating member 45 is preferably the same as the cover member 47 or is made of a material having a smaller dielectric constant than the cover member 47. Therefore, when the dielectric constant of the cover member 47 is 10 or more, it is preferable to use a material having a dielectric constant of 10 or less of the insulating member 45. When the dielectric constant of the cover member 47 is 4 or more, It is preferable that the insulating member 45 be formed of a material having a dielectric constant of 4 or less. As an example of a preferable combination of the insulating member 45 and the cover member 47, a case where the insulating member 45 is a resin sheet made of polytetrafluoroethylene or the like, and the cover member 47 is a ceramic plate material such as alumina or the like is mentioned. In this case, the thickness of the resin sheet is made of ceramics in order to increase the electrical impedance of the gate opening 41 as viewed from the plasma and prevent the generation of local plasma, for example, in a range of 2 mm to 10 mm. The thickness of the plate material can be set within a range of, for example, 10 mm or more and 18 mm or less from the viewpoint of reliably protecting the insulating member 45 from the plasma. However, in order to sufficiently secure the clearance with the substrate S passing through the gate opening 41, the total thickness of the thickness of the resin sheet and the thickness of the ceramic plate material is preferably set to, for example, 20 mm or less.

The inductively coupled plasma processing apparatus 1 of this embodiment is provided with a cover member 47 and an insulating member 45 having the same dielectric constant as the cover member 47 or a material smaller than the cover member 47 in combination with the gate opening 41. As a result, the total thickness of the insulating member 45 and the cover member 47 required to prevent the generation of localized plasma can be reduced compared to the case where the cover member 47 is separately provided. As a result, without expanding the gate opening portion 41 itself, it is possible to sufficiently secure a gap required for passing the substrate S through the gate opening portion 41. In addition, even if a large bias voltage is applied to the base 22 from the high-frequency power source 29, the generation of localized plasma in the gate opening 41 can be prevented.

<First Modification>

As described above, the inner wall surface of the main body container 2A may be treated with an acid-resistant aluminum (anodic oxidation treatment) to form an acid-resistant aluminum film as an insulating protective film, and the bushing 60 may be omitted. FIG. 4 shows a modified example of forming an acid-resistant aluminum film 61 as an insulating protective film on the inner wall surface of the main body container 2A without providing the liner 60 in the inductively coupled plasma processing apparatus 1. When the acid-resistant aluminum film 61 is formed on the inner wall surface of the main body container 2A, the electrical impedance of the gate opening 41 viewed from the plasma can be made larger than the acid-resistant aluminum film 61 of the main body container 2A by the insulating member 45, so that it can be prevented An abnormal discharge of the gate opening portion 41 or generation of a local plasma.

<Electromagnetic wave shielding member>

Next, referring to FIG. 5 and FIG. 6, an electromagnetic wave shielding member provided in the observation opening portion 43 as a through opening portion will be described. FIG. 5 is a front view of the side wall 2c including the observation opening 43 in a state where the electromagnetic wave shielding member is installed. FIG. 6 is a cross-sectional view taken along a line VI-VI of FIG. 5 and includes an observation opening including a state in which an electromagnetic wave shielding member is installed; 43 is a sectional view of a main part of the side wall 2c. A bushing 60 is attached to the opening bottom surface 43a, the opening ceiling surface 43b, and the two opening side surfaces 43c of the observation opening portion 43 so as to cover these.

The electromagnetic wave shielding plate 49 is formed in a plate shape and is made of a conductive material such as a metal such as stainless steel or aluminum in order to shield electromagnetic waves. The electromagnetic wave shielding plate 49 has a plurality of cavities 49a so that the inside of the processing chamber 5 can be visually confirmed from the outside of the processing container 2. The electromagnetic wave shielding plate 49 is an end portion provided on the inner side of the main body container 2A in the observation opening portion 43. The electromagnetic wave shielding plate 49 is attached to the side wall 2c of the main body container 2A through a bushing 60 by a fixing means such as a metal screw 80 or the like. The electromagnetic wave shielding plate 49 is electrically connected to the grounded main body container 2A by, for example, a screw 80.

The electromagnetic wave shielding plate 49 is provided so as to cover an end portion on the processing chamber 5 side of the observation opening portion 43. A transmission window 70 made of a material such as quartz is arranged on the other end side of the observation opening 43. Through the transmission window 70, the observation opening 43, and the electromagnetic wave shielding plate 49, the state in the processing chamber 5 such as the emission of plasma can be observed. By disposing the electromagnetic wave shielding plate 49 in the observation opening portion 43, it is possible to prevent electromagnetic waves from entering the observation opening portion 43, and to prevent abnormal discharge or localized plasma generation in the observation opening portion 43. In addition, by providing the electromagnetic wave shielding plate 49, it is possible to suppress adhesion or deposition in the observation opening 43.

Next, a processing operation when the substrate S is subjected to plasma processing using the inductively coupled plasma processing apparatus 1 configured as described above will be described.

First, in a state where the gate valve 50 is opened, the substrate S is transferred into the processing chamber 5 by a transfer mechanism (not shown), and placed on the mounting surface 22A of the susceptor 22, and then the electrostatic chuck or the like The substrate S is fixed on the base 22.

Next, the processing gas is discharged from the gas supply device 20 through the gas supply pipe 21 and a gas flow path (not shown) and a plurality of openings in the support beam 16 into the processing chamber 5. The exhaust pipe 31 is configured to evacuate the inside of the processing chamber 5 to maintain the inside of the processing container at a pressure environment of, for example, about 1.33 Pa.

Next, a high-frequency power of 13.56 MHz is applied from the high-frequency power source 15 to the antenna 13, thereby forming a uniform induced electric field in the processing chamber 5 through the dielectric wall 6. The processing gas is plasmatized in the processing chamber 5 by the induced electric field formed as described above, thereby generating a high-density inductively coupled plasma. The ions in the plasma generated in this way are effectively pulled into the substrate S by the high-frequency power applied to the base 22 from the high-frequency power source 29, and the substrate S is subjected to a uniform plasma treatment.

During the plasma treatment, since the electrical impedance of the gate opening portion 41 viewed from the plasma is maintained higher than the bushing 60 (or the acid-resistant aluminum film 61) by the insulating member 45 as an impedance adjustment member, it is possible to The occurrence of localized plasma in the gate opening 41 is suppressed. In addition, the electromagnetic wave shielding plate 49 can prevent electromagnetic waves from entering the observation opening portion 43 and suppress the generation of localized plasma of the observation opening portion 43. Therefore, in the inductively coupled plasma processing apparatus 1, the plasma can be stably generated in the processing chamber 5, and the processing in the plane of the substrates S and between the substrates S can be made uniform.

<Second Modification>

Next, referring to FIG. 7, a second modification example in which the impedance adjustment member is disposed in the observation opening portion 43 will be described. As described above, by installing the electromagnetic wave shielding plate 49 in the observation opening 43 (see FIG. 6), it is possible to prevent the occurrence of abnormal discharge or localized plasma in the observation opening 43. However, as shown in FIG. 7, an observation member 43 may be provided with an insulating member 46 as an impedance adjusting member instead of the electromagnetic wave shielding plate 49.

FIG. 7 is a cross-sectional view of a main part of the side wall 2c including the observation opening 43 of the second modification. The opening bottom surface 43 a of the observation opening portion 43 is provided with an insulating member 46 as an impedance adjusting member. In addition, the insulating member 46 may be provided not only on the opening bottom surface 43a but also on the opening side surface 43c and / or the opening ceiling surface 43b. Further, it is preferable to provide the cover member 48 on the insulating member 46 as the impedance adjusting member.

The configuration of the insulating member 46 and the cover member 48 provided in the observation opening portion 43 is the same as that of the insulating member 45 and the cover member 47 in the gate opening portion 41 except that there is less restriction on thickness. In this modification, the thickness of the insulating member 46 provided in the observation opening portion 43 is to increase the electrical impedance of the observation opening portion 43 observed from the plasma (to be precise, the observation opening portion 43 It is equipped with the electrical impedance of the wall surface of the insulating member 46) and prevents abnormal discharge or localized plasma, and can be set to a sufficient arbitrary thickness, for example, within a range of 10 mm to 20 mm. In addition, the thickness of the cover member 48 provided in the observation opening portion 43 is to securely protect the insulating member 46 from the plasma. The thickness can be set to a sufficient arbitrary thickness, for example, within a range of 10 mm to 20 mm.

As described above, according to the inductively coupled plasma processing apparatus 1 of this embodiment, it is possible to effectively prevent the generation of localized plasma of the gate opening 41 by the insulating member 45 as an impedance adjusting member.

As mentioned above, although the embodiment of this invention was described in detail for the purpose of illustration, this invention is not limited to the said embodiment, Various deformation | transformation is possible. For example, in the above embodiment, although an inductively coupled plasma device is used as an example, as long as it is a plasma processing device having an opening in a processing container, the present invention can be applied without limitation. Plasma devices, surface wave plasma devices, ECR (Electron Cyclotron Resonance) plasma devices, spiral wave plasma devices and other types of plasma devices. In addition, the present invention is not limited to a dry etching apparatus, and is equally applicable to a film forming apparatus, an ashing apparatus, and the like.

In addition, the present invention is not limited to a case where the substrate for FPD is used as the object to be processed, and it can also be applied to a case where a substrate for semiconductor wafer or a solar cell is used as the object to be processed.

Claims (13)

A plasma processing device generates a plasma inside a processing container, and a plasma processing device for processing a substrate is characterized in that the processing container includes a wall formed with a through opening, and the through opening includes Corresponding opening bottom surfaces, opening ceiling surfaces, and two opening side surfaces, at least the opening bottom surface is provided with an impedance adjusting member for adjusting the electrical impedance passing through the opening portion, and the impedance adjusting member is provided with a laminated layer A cover member made of a dielectric material, the cover member protects the impedance adjustment member from a plasma, and the impedance adjustment member is made of a material having a smaller dielectric constant than the cover member. For example, the plasma processing apparatus according to item 1 of the patent application scope, wherein the through-opening portion is a gate opening portion that carries in and out the substrate. For example, the plasma processing device according to item 1 or 2 of the patent application range, wherein the impedance adjusting member is made of a material having a dielectric constant of 10 or less. For example, the plasma processing apparatus according to item 1 or 2 of the patent application range, wherein the impedance adjusting member is made of a material having a dielectric constant of 4 or less. For example, the plasma processing apparatus according to item 1 or 2 of the patent application range, wherein the impedance adjusting member is formed in a sheet shape from a resin material having a dielectric constant of 4 or less. For example, the plasma processing device according to item 1 or 2 of the patent application scope, wherein the impedance adjusting member is a sheet made of polytetrafluoroethylene. For example, the plasma processing apparatus according to item 1 of the application, wherein the cover member is made of ceramics. For example, the plasma processing apparatus according to item 1 or 2 of the patent application scope includes an insulating protective member that protects the inner wall surface from the plasma along the inner wall surface of the processing container, and through the impedance adjusting member. So that the electrical impedance of the through-opening portion viewed from the plasma is higher than the protective member. For example, the plasma processing apparatus according to item 8 of the scope of patent application, wherein the electrical impedance of the impedance adjusting member is greater than 8Ω with respect to the electrical impedance of the protective member. For example, the plasma processing device of the scope of application for patents 1 or 2, wherein the inner wall surface of the processing container is formed with an insulating protective film for protecting the inner wall surface from the plasma, and the impedance adjusting member is used to make The electrical impedance of the through opening as viewed from the plasma is higher than the protective film. For example, the plasma processing apparatus according to item 10 of the application, wherein the electrical impedance of the impedance adjusting member is greater than or equal to 8Ω relative to the electrical impedance of the insulating protective film. For example, the plasma processing apparatus of claim 10, wherein the processing container is composed of aluminum, and the insulating protective film is composed of an acid-resistant aluminum film. For example, the plasma processing apparatus according to item 1 or 2 of the patent application scope includes an observation opening as the penetrating opening for observing the inside of the processing container from the outside. An end portion on the inner side of the processing container is provided with an electromagnetic wave shielding plate made of a conductive material having a plurality of cavities for shielding electromagnetic waves from entering the observation opening portion.