TWI840450B - Shower heads and gas handling devices - Google Patents

Abstract

[Topic] Provide a shower head and gas treatment device that can suppress corrosion even when using highly corrosive process gases. [Solution] A shower head supplies a corrosive treatment gas to a chamber in which a substrate is arranged in a gas treatment device for applying gas treatment to a substrate. The shower head comprises: a base member; a spray plate having a plurality of gas discharge holes for discharging the treatment gas; a gas diffusion space which is a portion disposed between the base member and the spray plate, into which the treatment gas is introduced and which is connected to the plurality of gas discharge holes. The base member and the spray plate are substrates made of metal, and a portion of the base member facing the gas diffusion space and a portion of the spray plate facing the gas diffusion space and the gas discharge holes are covered with a corrosion-resistant metal material or a corrosion-resistant film.

Description

Shower heads and gas handling devices

The present disclosure relates to showerheads and gas handling devices.

In the manufacturing process of flat panel displays (FPD) such as liquid crystal display devices (LCD), there is a process of plasma processing such as plasma etching of a specific film on a rectangular glass substrate. As such a plasma processing device, an inductively coupled plasma (ICP) processing device has attracted attention because of its great advantages such as being able to obtain high vacuum and high density plasma.

In the past, an inductively coupled plasma processing device had a rectangular dielectric window corresponding to the substrate to be processed between the high-frequency antenna and the processing chamber. However, as the size of the substrate increases, an inductively coupled plasma processing device using a metal window has recently been proposed (Patent Document 1). In Patent Document 1, the rectangular metal window is divided and insulated from each other to form the ceiling of the processing chamber. The multiple divided pieces constituting the metal window function as a showerhead for discharging gas, and the processing gas is introduced into the chamber. When such a device is used for plasma etching, a highly corrosive gas such as _Cl2 gas is used. [Prior Technical Document] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2016-225018

[The problem the invention is trying to solve]

The present disclosure provides a shower head and a gas treatment device that can suppress corrosion even when using highly corrosive treatment gas. [Technical means to solve the problem]

A shower head related to one aspect of the present disclosure is a gas treatment device for applying gas treatment to a substrate, and supplies a corrosive treatment gas to a chamber in which the substrate is arranged. The shower head comprises: a base member; a shower plate having a plurality of gas discharge holes for discharging the treatment gas; and a gas diffusion space, which is a portion disposed between the base member and the shower plate, into which the treatment gas is introduced and which is connected to the plurality of gas discharge holes. The base member and the shower plate are substrates made of metal, and a portion of the base member facing the gas diffusion space and a portion of the shower plate facing the gas diffusion space and the gas discharge holes are covered with a corrosion-resistant metal material or a corrosion-resistant film. [Effect of the invention]

According to the present disclosure, a shower head and a gas treatment device are provided which can suppress corrosion even when using highly corrosive treatment gas.

The following is a description of the embodiment with reference to the attached drawings. [Plasma treatment device] First, a plasma treatment device for a shower head applicable to an embodiment is described. FIG1 is a cross-sectional view showing an example of a plasma treatment device for a shower head applicable to an embodiment.

The plasma processing apparatus shown in FIG. 1 is constructed as an inductively coupled plasma processing apparatus and can be suitably used for etching a metal film when forming a thin film transistor on a rectangular substrate, for example, a glass substrate for FPD.

The inductively coupled plasma processing device has an airtight main body container 1 made of a conductive material, such as aluminum whose inner wall surface is anodized and has a square tube shape. The main body container 1 is assembled to be decomposable and is electrically grounded via a grounding wire 1a.

The main body container 1 is divided into upper and lower parts by a rectangular shower head 2 insulated from the main body container 1. The upper part becomes an antenna container 3 for dividing the antenna room, and the lower part becomes a chamber (processing container) 4 for dividing the processing room. The shower head 2 functions as a metal window and constitutes the ceiling of the chamber 4.

A support frame 5 and a support beam 6 protruding toward the inner side of the main body container 1 are provided between the side wall 3a of the antenna container 3 and the side wall 4a of the chamber 4. The support frame 5 and the support beam 6 are made of a conductive material, preferably a metal such as aluminum. The shower head 2 is divided into a plurality of parts via an insulating member 7. Moreover, the divided parts of the shower head 2 are supported by the support frame 5 and the support beam 6 via the insulating member 7. The support beam 6 is suspended from the ceiling of the main body container 1 by a plurality of hanging rods (not shown). In addition, the shower head 2 may be suspended from the ceiling of the main body container 1 by a plurality of hanging rods (not shown) instead of providing the support beam 6.

As described later, each division part 50 of the shower head 2 serving as a metal window has a base member 52, a shower plate 53 having a plurality of gas ejection holes 54, and a box-shaped gas diffusion space 51 in a portion between the base member 52 and the shower plate 53. A concave portion is provided in the center of the base member 52, and the outer side portion of the concave portion of the base member 52 and the shower plate 53 are fixed by screws, and the area surrounded by the concave portion of the base member 52 and the shower plate 53 serves as the gas diffusion space 51. In the gas diffusion space 51, the process gas is introduced from the process gas supply mechanism 20 through the gas supply pipe 21. The gas diffusion space 51 is communicated with a plurality of gas discharge holes 54 , and the processing gas is discharged from the gas diffusion space 51 through the plurality of gas discharge holes 54 .

A high frequency antenna 13 is arranged in the antenna container 3 above the shower head 2 so as to face the surface of the shower head 2 opposite to the chamber 4. The high frequency antenna 13 is made of a conductive material such as copper, and is arranged to be separated from the shower head 2 by a spacer (not shown) made of an insulating member, and is formed into, for example, a spiral shape in the surface corresponding to the rectangular shower head 2. Furthermore, it may be formed into a ring shape, and the antenna may be one or more.

Each high frequency antenna 13 is connected to a first high frequency power source 18 via a power supply line 16 and a matching unit 17. During plasma processing, for example, high frequency power of 13.56 MHz is supplied to the high frequency antenna 13 via the power supply line 16 extending from the first high frequency power source 18. Accordingly, as described later, a circulating current excited by the shower head 2 functioning as a metal window forms an induced electric field in the chamber 4. Furthermore, by the induced electric field, the processing gas supplied from the shower head 2 is plasmatized in the plasma generating space S directly below the shower head 2 in the chamber 4, generating inductively coupled plasma. That is, the high frequency antenna 13 and the first high frequency power source 18 function as a plasma generating mechanism.

At the bottom of the chamber 4, a mounting table 23 for mounting a rectangular FPD glass substrate (hereinafter simply referred to as a substrate) G as a substrate to be processed is fixed via an insulating member 24 in a manner that sandwiches the shower head 2 and faces the high-frequency antenna 13. The mounting table 23 is made of a conductive material, such as aluminum with an anodized surface. The substrate G mounted on the mounting table 23 is held by adsorption by an electrostatic fixture (not shown).

An insulating shielding ring 25a is provided on the upper peripheral portion of the mounting table 23, and an insulating ring 25b is provided on the peripheral surface of the mounting table 23. In the mounting table 23, a lifting pin 26 for carrying in and out the substrate G is inserted through the bottom wall of the main container 1 and the insulating member 24. The lifting pin 26 is lifted and driven by a lifting mechanism (not shown) provided outside the main container 1 to carry in and out the substrate G.

A matching device 28 and a second high-frequency power source 29 are provided outside the main body container 1. The second high-frequency power source 29 is connected to the mounting table 23 through the matching device 28 via a power supply line 28a. The second high-frequency power source 29 applies a high-frequency power for biasing the mounting table 23 during plasma processing, for example, a high-frequency power with a frequency of 3.2 MHz. The ions in the plasma in the chamber 4 are effectively introduced into the substrate G by the self-bias generated by the high-frequency power for biasing.

Furthermore, a temperature control mechanism composed of a heating means such as a heater or a cooling medium flow path, and a temperature sensor (neither of which is shown in the figure) are provided in the mounting table 23 to control the temperature of the substrate G. The pipes or wiring corresponding to these mechanisms or components are all led out of the main body container 1 through the opening 1b provided on the bottom surface of the main body container 1 and the insulating member 24.

The side wall 4a of the chamber 4 is provided with a loading and unloading port 27a for loading and unloading the substrate G, and a gate valve 27 for opening and closing the port. Furthermore, an exhaust device 30 including a vacuum pump is connected to the bottom of the chamber 4 through an exhaust pipe 31. The chamber 4 is exhausted by the exhaust device 30, and during the plasma treatment, the chamber 4 is set and maintained in a specific vacuum environment (e.g., 1.33 Pa).

A cooling space (not shown) is formed on the back side of the substrate G placed on the mounting table 23, and a He gas flow path 41 is provided for supplying He gas as a heat transfer gas at a certain pressure. In this way, by supplying the heat transfer gas to the back side of the substrate G, the temperature rise or temperature change caused by the plasma treatment of the substrate G can be suppressed under vacuum.

The inductively coupled plasma processing device further has a control unit 100. The control unit 100 is composed of a computer, and has a main control unit composed of a CPU that controls each component of the plasma processing device, an input device, an output device, a display device, and a memory device. The memory device stores parameters of various processes performed in the plasma processing device, and further, a memory medium is set to store a program for controlling the processes performed in the plasma processing device, that is, a process recipe. The main control unit controls the plasma processing device by calling out a specific process recipe stored in the memory medium and causing the plasma processing device to perform a specific process according to the process recipe.

[Shower head] Next, a detailed description is given of the shower head 2 involved in one embodiment. Inductively coupled plasma generates plasma by passing a high-frequency current through a high-frequency antenna, generating a magnetic field around it, and generating high-frequency discharge using the induced electric field excited by the magnetic field. In the case of using a metal window as the wall of the chamber 4, in the high-frequency antenna 13 that is arranged to be surrounded in a circumferential direction within a plane, the eddy current and the magnetic field do not reach the back side of the metal window, that is, the side of the chamber 4, so plasma is not generated. Therefore, in this embodiment, the shower head 2 functioning as a metal window is divided into a plurality of parts by the insulating member 7 in such a manner that the magnetic field and eddy current generated by the high-frequency current flowing through the high-frequency antenna 13 reach the chamber 4 side.

The partition 50 of the shower head 2 is composed of a base member 52 and a base member of a shower plate 53 made of non-magnetic metal, and at least the base member 52 is made of, for example, aluminum (or an aluminum alloy). The base member 52 and the shower plate 53 are sealed by a sealing member (not shown in FIG. 1 ).

The portion of the shower head 2 that contacts the processing gas, that is, the portion of the base member 52 of the partition 50 facing the gas diffusion space 51, and the portion of the shower plate 53 facing the gas diffusion space 51 and the gas discharge hole 54, is covered with a corrosion-resistant metal material or a corrosion-resistant film having a degree of corrosion resistance that does not corrode even when in contact with the processing gas introduced into the gas diffusion space 51. Furthermore, the sealing member is arranged so that the processing gas does not directly contact the base material of the base member 52 and the base material of the shower plate 53. Below, several specific examples of the shower head 2 (partition 50) are described.

[First Example] Figure 2 is a cross-sectional view showing the first example of the shower head 2 (dividing portion 50). In this example, the base material 61 of the base member 52 and the base material 71 of the shower plate 53 are both made of aluminum. It is preferable to use an aluminum material whose surface is anodized.

The base member 52 has a cover member 62 made of a corrosion-resistant metal and arranged to cover the base member 61 at a portion facing the gas diffusion space 51. The cover member 62 is formed into a box shape along the gas diffusion space 51. As the corrosion-resistant metal constituting the cover member 62, stainless steel or nickel-based alloys such as Hoechst or nickel-containing metals are preferred. Other corrosion-resistant metals such as titanium can also be used.

The spray plate 53 has a plurality of sleeves 72 provided at a portion facing the gas discharge hole 54, a corrosion-resistant film 73 provided at a portion facing the gas diffusion space 51, and a plasma-resistant film 74 provided at a portion facing the plasma generation space S.

The sleeve 72 is embedded in the base material 71 to define the gas discharge hole 54. The sleeve 72 is made of corrosion-resistant metal or ceramic. As the corrosion-resistant metal, stainless steel or nickel-based alloys such as Hoechst or nickel-containing metals are preferred. Other corrosion-resistant metals such as titanium can also be used. As ceramics, alumina, quartz, etc. can be used.

The gas discharge hole 54 has a large diameter portion on the gas diffusion space 51 side and a small diameter portion on the plasma generation space S side. The small diameter portion on the plasma generation space S side is used to prevent plasma from entering the plasma generation space S into the depth of the gas discharge hole 54.

The corrosion-resistant film 73 is made of a material that is corrosion-resistant to the process gas. A ceramic spray film or Teflon (registered trademark) coating is preferred as the corrosion-resistant film 73, and an alumina (Al ₂ O ₃ ) spray film is particularly preferred. As the spray film, a film impregnated with an impregnating material is more preferred, and as the impregnating material, a synthetic resin such as acrylic resin, epoxy resin or silicone resin is used.

The plasma-resistant film 74 is made of a material that is durable against the plasma of the processing gas generated in the plasma space S. As the plasma-resistant film 74, a ceramic spray film is preferred, and a _yttrium oxide spray film such as a yttrium oxide ( _Y2O3 ) spray film or a Y-Al-Si-O system mixed spray film (a mixed spray film of yttrium oxide, aluminum oxide and silicon dioxide (or silicon nitride)) having high plasma resistance is more preferred. As a spray film, one that is impregnated with an impregnating material is more preferred, and as an impregnating material, a synthetic resin such as an acrylic resin, an epoxy resin or a silicone resin is used.

The base member 61 of the base member 52 and the base member 71 of the spray plate 53 are fixed by screws in a manner of contacting each other outside the gas diffusion space 51, and a sealing member 81 is provided inside the contact portion in a manner of sealing the two. The cover member 62 has a bent portion 62a that is bent in a state where the end portion does not contact the surface of the spray plate 53, and the bent portion 62a is provided in a state of contacting the annular sealing member 81 in a manner of pressing. The front end portion of the bent portion 62a contacts the surface of the base member 52. The sealing member 81 is retained by the bent portion 62a. Furthermore, the sealing member 81 contacts the corrosion-resistant film 73. Accordingly, the corrosive process gas is prevented from reaching the outer side portion of the gas diffusion space 51 of the substrate 61 and the substrate 71. The cover member 62 is mounted on the substrate 61 by the mounting member 82. A sealing member 89 is provided between the mounting member 82 and the cover member 62, and the corrosive process gas is prevented from reaching the substrate 61. Furthermore, the cover member 62 is bent in a state where a gap is provided without contacting the surface of the spray plate 53. Therefore, it is possible to suppress the occurrence of local discharge between the cover member 62 and the substrate 71 when the circulating current is excited by the spray head 2. In addition, the generation of particles caused by the friction between the cover member 62 and the spray plate 53 due to the difference in thermal expansion is suppressed.

In this way, the gas contacting parts facing the gas diffusion space 51 and the gas discharge hole 54 can be covered with corrosion-resistant materials with a relatively simple structure, without greatly changing the structure of the existing shower head 2, and can effectively suppress the corrosion of the shower head 2 to the relatively corrosive process gas. Furthermore, since the sealing member 81 is sealed, the corrosive process gas can be effectively suppressed from reaching the base material 61 of the base member 52 and the base material 71 of the shower plate 53. In addition, since the sealing member 81 uses fluororubber or the like that is corrosion-resistant to the relatively corrosive process gas, the corrosion of the sealing member 81 is also suppressed.

[Second Example] Figure 3 is a cross-sectional view showing the second example of the shower head 2 (dividing portion 50). In this example, the basic structure is the same as that of the first example. In this example, the sealing member 81 is not the cover member 62, but is held and fixed by the corrosion-resistant fixing member 83 forming a ring, which is different from the first example. The corrosion-resistant fixing member 83 is made of an insulating corrosion-resistant resin such as PTFE (polytetrafluoroethylene) and is fixed by the fixing member 84. The fixing member 84 is installed on the substrate 61 together with the cover member 62 through the mounting member 82. A sealing member 89 is provided between the mounting member 82 and the cover member 62 to prevent the corrosive process gas from reaching the substrate 61. Furthermore, in this example, the sealing member 81 is in contact with the cover member 62 and the corrosion-resistant film 73. Therefore, this example can also obtain the same effect as the first example. Furthermore, since the sealing member 81 disposed between the base member 52 and the spray plate 53 is held by the corrosion-resistant fixing member 83 made of an insulating corrosion-resistant resin, it is possible to prevent discharge from occurring between the corrosion-resistant fixing member 83 and the spray plate 53.

[Third Example] Figure 4 is a cross-sectional view showing the third example of the shower head 2 (dividing portion 50). In this example, the shower plate 53 is the same as the first example, and has a base material 71, a plurality of sleeves 72, an corrosion-resistant film 73, and a plasma-resistant film 74.

In addition, the base member 52 has a corrosion-resistant film 63 formed to cover the upper surface side of the gas diffusion space 51 of the substrate 61, and a ring-shaped member 64 made of a corrosion-resistant metal provided to cover the side surface side of the gas diffusion space 51 of the substrate 61.

As the corrosion-resistant film 63, similar to the corrosion-resistant film 73, a ceramic spray film or Teflon (registered trademark) coating is preferred, and an alumina spray film is particularly preferred. As the spray film, it is more preferred to use a film impregnated with an impregnating material, and as the impregnating material, a synthetic resin such as acrylic resin, epoxy resin or silicone resin is used.

The ring member 64 is made of a corrosion-resistant metal. Stainless steel, nickel-based alloys such as Hoechst, and nickel-containing metals are preferred as the corrosion-resistant metal. Other corrosion-resistant metals such as titanium may also be used.

Annular grooves are formed on the upper and lower surfaces of the annular member 64, and sealing members 85 and 86 are respectively embedded in these grooves. The sealing members 85 and 86 are respectively formed to be closely attached to the surface of the base member 52 formed with the corrosion-resistant film 63 and the surface of the spray plate 53 formed with the corrosion-resistant film 73. The base member 61 of the base member 52 and the base member 71 of the spray plate 53 are fixed by screw fixing, and the base member 52 and the annular member 64, and the annular member 64 and the spray plate 53 are sealed by the sealing members 85 and 86.

Thus, even in this example, the gas contacting parts facing the gas diffusion space 51 and the gas discharge hole 54 can be covered with corrosion-resistant materials with a relatively simple structure, without greatly changing the structure of the existing shower head 2, and can effectively suppress the corrosion of the shower head 2 relative to the corrosive process gas. Furthermore, since the sealing members 85 and 86 are in close contact with the annular member 64 formed of the corrosion-resistant metal and the corrosion-resistant films 63 and 73, the corrosive process gas is prevented from reaching the substrates 61 and 71 from the gap between the sealing members 85 and 86 and the annular member 64. Furthermore, since the sealing members 85 and 86 are made of fluororubber or the like which is resistant to the corrosive process gas, corrosion caused by the process gas is also suppressed.

[Example 4] Figure 5 is a cross-sectional view showing the fourth example of the shower head 2 (dividing portion 50). In this example, although the basic structure is the same as that of the third example, a cover member 65 made of a corrosion-resistant metal similar to the cover member 62 is provided on the upper side of the gas diffusion space 51 of the substrate 61, replacing the corrosion-resistant film 63 of the third example. The cover member 65 is mounted on the substrate 61 by the mounting member 82. A sealing member 89 is provided between the mounting member 82 and the cover member 65, and the corrosive process gas is prevented from reaching the substrate 61.

In this example, similar to the third example, the gas diffusion space 51 and the gas outlet hole 54 that are in contact with the gas are all covered with corrosion-resistant materials, so that the same effect as the third example can be achieved.

[Fifth Example] Figure 6 is a cross-sectional view showing the fifth example of the shower head 2 (dividing portion 50). In this example, an integrated member 66 is provided in which the cover member 65 and the annular member 64 of the fourth example are integrated, and the rest is the same as the fourth example. The integrated member 66 is the same as the example of Figure 4 and is mounted on the substrate 61 by the mounting member 82. A sealing member 89 is provided between the mounting member 82 and the integrated member 66 to prevent the corrosive process gas from reaching the substrate 61.

Therefore, in addition to achieving the same effect as in the fourth example, the risk of the process gas leaking from the gap between the cover member 65 and the ring member 64 to the substrate 61 side of the base member 52, which exists in the fourth example, can be eliminated.

[Sixth Example] Figure 7 is a cross-sectional view showing the sixth example of the shower head 2 (dividing portion 50). In this example, the shower plate 53 is the same as the first example, and has a base material 71, a plurality of sleeves 72, an corrosion-resistant film 73, and a plasma-resistant film 74.

In addition, the base member 52 has a corrosion-resistant film 67 on the entire surface of the portion of the gas diffusion space 51 facing the substrate 61. As the corrosion-resistant film 67, similar to the corrosion-resistant film 73, a ceramic spray film or a Teflon (registered trademark) coating is preferred, and an alumina spray film is particularly preferred. As the spray film, it is more preferred to use an impregnation material, and as the impregnation material, a synthetic resin such as an acrylic resin, an epoxy resin, or a silicone resin is used.

Furthermore, an annular groove 52a is formed on the outer side of the gas diffusion space 51 on the lower surface of the substrate 61 of the base member 52. The corrosion-resistant film 67 extends along the lower surface of the substrate 61 to the outside of the gas diffusion space 51 and is also formed in the annular groove 52a. Furthermore, the corrosion-resistant film 73 of the spray plate 53 extends along the upper surface of the substrate 71 to the portion corresponding to the annular groove 52a outside the gas diffusion space.

The base member 61 of the base member 52 and the base member 71 of the spray plate 53 are screwed and fixed in a state where the annular sealing member 87 is inserted into the annular groove 52a. As the sealing member 87, fluororubber or the like which is corrosive to the corrosive process gas can be used.

Thus, even in this example, the gas contacting parts facing the gas diffusion space 51 and the gas discharge hole 54 can be covered with the corrosion-resistant material with a relatively simple structure, without greatly changing the structure of the existing shower head 2, and can effectively suppress the corrosion of the shower head 2 relative to the corrosive process gas. Furthermore, the joint between the base member 52 and the shower plate 53 can more effectively suppress the corrosion caused by the corrosive process gas because the sealing member 87 is interposed between the corrosion-resistant films 67 and 73.

[Seventh Example] Figure 8 is a cross-sectional view of the seventh example of the shower head 2 (dividing portion 50). In this example, the base member 52 is the same as the sixth example, and the entire portion of the base member 61 facing the gas diffusion space 51 has a corrosion-resistant film 67. The corrosion-resistant film 67 extends along the bottom surface of the base member 61 to the outside of the gas diffusion space 51. However, the points where the peripheral portion of the gas diffusion space 51 is inclined and the points where the annular groove is not formed are different from the sixth example.

In addition, the spray plate 53 has a substrate 75 made of a corrosion-resistant metal, and a plasma-resistant film 74 is formed on a portion of the plasma generating space S facing the substrate 75. The gas discharge hole 54 is directly formed on the substrate 75. The substrate 75 is exposed to the gas diffusion space 51 and the gas discharge hole 54. As the corrosion-resistant metal constituting the substrate 75, stainless steel or nickel-based alloys such as Herschel and nickel-containing metals are preferred. Other corrosion-resistant metals such as titanium can also be used. An annular groove 53a is formed on the outer side of the gas diffusion space 51 on the upper side of the spray plate 53. In addition, the corrosion-resistant film 67 of the base member 52 extends to the outer side of the annular groove 53a.

The base material 61 of the base member 52 and the base material 75 of the spray plate 53 are screwed and fixed in a state where the annular sealing member 88 is inserted into the annular groove 53a. As the sealing member 88, fluororubber or the like which is corrosive to the corrosive process gas can be used.

Since the base member 52 is large in size, it is difficult to use corrosion-resistant metals such as stainless steel due to weight restrictions, etc. However, the spray plate 53 is small in size, so as in this example, the entire body except for the plasma-resistant film 74 can be made of corrosion-resistant metals such as stainless steel.

Thus, even in this example, the gas contacting parts facing the gas diffusion space 51 and the gas discharge hole 54 can be covered with corrosion-resistant materials with a relatively simple structure, without greatly changing the structure of the existing shower head 2, and can effectively suppress the corrosion of the shower head 2 relative to the corrosive process gas. Furthermore, the joint between the base member 52 and the shower plate 53 is sealed by the base material 75 composed of the corrosion-resistant film 67 and the corrosion-resistant metal, and further, because the sealing member 88 is interposed therebetween, the corrosion caused by the corrosive process gas can be more effectively suppressed.

Furthermore, by being inclined at the periphery of the gas diffusion space 51, the side surface of the gas diffusion chamber 51 becomes gentle (blunt when viewed in cross section), so that when the corrosion-resistant film 67 is formed by spraying, for example, a dense film with a high adhesion density of the sprayed material particles can be formed.

[Example 8] Figure 9 is a cross-sectional view of the shower head 2 (dividing portion 50) of Example 8. In this example, the basic structure is the same as that of Example 7. In this example, in the base member 52, a cover member 68 made of corrosion-resistant metal is provided on the entire portion of the gas diffusion space 51 facing the substrate 61, which is different from Example 7 in that the corrosion-resistant film 67 is replaced by a cover member 68. As the corrosion-resistant metal, nickel-containing metals such as stainless steel or nickel-based alloys such as Herschel are preferred. Other corrosion-resistant metals such as titanium can also be used. In addition, the cover member 68 is mounted on the substrate 61 by the mounting member 82. A sealing member 89 is provided between the mounting member 82 and the cover member 68, and corrosive process gases are prevented from reaching the substrate 61.

In this example, since the corrosive film 67 of the seventh example is merely replaced by a cover member 68 made of a corrosion-resistant metal, the same effect as that of the seventh example can be obtained.

(Operation of plasma processing device) Next, the processing operation when the substrate G is subjected to plasma processing, such as plasma etching processing, using the inductively coupled plasma processing device constructed as described above will be described.

First, the substrate G formed with a specific film is carried into the chamber 4 from the loading and unloading port 27a by the transport mechanism (not shown) with the gate valve 27 opened, and is placed on the mounting surface of the mounting table 23. Then, the substrate G is fixed on the mounting table 23 by an electrostatic clamp (not shown). Moreover, while the chamber 4 is vacuum-exhausted by the exhaust device 30, the pressure atmosphere in the chamber 4 is maintained at, for example, 0.66 to 26.6 Pa by the pressure control valve (not shown). In this state, the processing gas is supplied from the processing gas supply mechanism 20 through the gas supply pipe 21 to the shower head 2 having the function of a metal window, so that the processing gas is ejected from the shower head 2 into the chamber 4 in a spraying manner.

Furthermore, at this time, in the cooling space on the back side of the substrate G, in order to avoid the temperature rise or temperature change of the substrate G, He gas serving as heat transfer gas is supplied through the He gas flow path 41.

Next, a high frequency of, for example, 1 MHz to 27 MHz is applied to the high frequency antenna 13 from the first high frequency power source 18, thereby generating a uniform induced electric field in the chamber 4 through the shower head 2 functioning as a metal window. The induced electric field generated in this way plasmatizes the processing gas in the chamber 4, generating a high-density inductively coupled plasma. The plasma is used to perform plasma etching on the substrate G.

As a processing gas, fluorine or chlorine corrosive gases have been used in the past, but recently, the corrosiveness of the processing gas has increased due to the high temperature of the processing equipment. It is judged that when using such a highly corrosive processing gas, even for the contact part before plasma formation, especially in the upstream part of the plasma space S, sufficient corrosion countermeasures must be taken.

Patent Document 1 does not describe any measures to prevent corrosion inside the shower head 2 to which the process gas is supplied.

Therefore, in this embodiment, the portion of the shower head 2 (dividing portion 50) that contacts the processing gas, that is, the portion of the base member 52 facing the gas diffusion space 51, and the portion of the shower plate 53 facing the gas diffusion space 51 and the gas discharge hole 54 are covered with a corrosion-resistant metal material or a corrosion-resistant film. In this way, the corrosion of the portion of the metal shower head that contacts the gas can be suppressed with a relatively simple structure.

Specifically, as shown in the first to eighth examples, the portion of the base member 52 facing the gas diffusion space 51 uses a cover member 62 made of a corrosion-resistant metal such as stainless steel, corrosion-resistant films 63 and 67 such as ceramic spray films, and a ring member 64 made of a corrosion-resistant metal. Furthermore, a corrosion-resistant film 73 is provided on the portion of the spray plate 53 facing the gas diffusion space 51, and a sleeve 72 made of a corrosion-resistant metal or ceramics, or a base material 71 of the spray plate 53 itself made of a corrosion-resistant metal, is provided on the portion facing the gas discharge hole 54. In this way, corrosion caused by the highly corrosive process gas of the spray head 2 can be effectively suppressed.

Furthermore, since the base member 52 substrate 61 and the spray plate 53 substrate 71 are sealed by corrosion-resistant metal or corrosion-resistant film and sealed by sealing members 81, 85, 86, 87, 88, the process gas is prevented from reaching the potentially corrosive metal parts.

As the corrosion-resistant film, ceramic spray film or Teflon (registered trademark) coating is preferred. In particular, when using a halogen-based highly corrosive processing gas such as _Cl2 gas, an alumina spray film is preferred. Furthermore, the spray film is preferably one in which the impregnated material is impregnated. By impregnating the impregnated material, the pores of the spray film are sealed, and the corrosion caused by the highly corrosive processing gas can be more effectively suppressed. As the impregnated material, a synthetic resin such as acrylic resin, epoxy resin or silicone resin can be used. These resins can improve the filling property or corrosion resistance by selecting the material of the hardener as the main agent, and can further enhance the corrosion inhibition effect caused by sealing.

Furthermore, since the surface of the spray plate 53 facing the plasma space S is covered with a plasma-resistant film 74 having plasma resistance to the plasma of the process gas, the process gas has high resistance to the plasma. As the plasma-resistant film 74, a ceramic spray film is preferred, and a yttrium oxide spray film such as a _yttrium oxide ( _Y2O3 ) spray film or a Y-Al-Si-O system mixed spray film (a mixed spray film of yttrium oxide, aluminum oxide and silicon dioxide (or silicon nitride)) is more preferred, which can obtain higher plasma resistance. Furthermore, from the viewpoint of obtaining higher plasma resistance, a spray film that is sealed by impregnation with an impregnating material is more preferred. Even in this case, as the impregnation material, a synthetic resin such as acrylic resin, epoxy resin or silicone resin can be used to improve the filling property and plasma resistance. (Other applicable)

Although the above is a description of the embodiments, it should be understood that the embodiments disclosed this time are all illustrative and not limiting. The above embodiments may be omitted, replaced or modified in various forms without departing from the scope of the attached patent application and its gist.

For example, in the above-mentioned embodiment, although an inductively coupled plasma processing apparatus is used, it is not limited to this. If the substrate is a metal shower head, other plasma processing apparatuses such as a capacitively coupled plasma processing apparatus may be used, and gas processing without using plasma may also be used. Furthermore, although the substrate of the base member and the substrate of the shower plate are made of non-magnetic metal, if it is other than an inductively coupled plasma processing apparatus, it is not limited to non-magnetic metal.

Furthermore, in the above-mentioned embodiment, although the etching apparatus is described as an example, the present invention is not limited thereto and can be applied to any gas processing apparatus using a highly corrosive gas such as ashing or CVD.

1: Main body container 2: Sprinkler head 3: Antenna container 4: Chamber 5: Support frame 6: Support beam 7: Insulation member 13: High frequency antenna 18: First high frequency power source 20: Processing gas supply mechanism 50: Divider 51: Gas diffusion space 52: Base member 53: Sprinkler plate 54: Gas outlet hole 61: Base material 62,65,68: Cover member 66: Integrated member 63,67: Corrosion-resistant film 64: Ring member 71,75: Base material 72: Sleeve 73: Corrosion-resistant film 74: Plasma-resistant film 81,85,86,87,88,89: Sealing member G: Substrate

[FIG. 1] is a cross-sectional view showing an example of a plasma treatment device using a shower head according to an embodiment. [FIG. 2] is a cross-sectional view showing the first example of a shower head. [FIG. 3] is a cross-sectional view showing the second example of a shower head. [FIG. 4] is a cross-sectional view showing the third example of a shower head. [FIG. 5] is a cross-sectional view showing the fourth example of a shower head. [FIG. 6] is a cross-sectional view showing the fifth example of a shower head. [FIG. 7] is a cross-sectional view showing the sixth example of a shower head. [FIG. 8] is a cross-sectional view showing the seventh example of a shower head. [FIG. 9] is a cross-sectional view showing the eighth example of a shower head.

2: Shower head

50: Division

51: Gas diffusion space

52: Base components

53:Spray board

54: Gas outlet hole

61: Base material

62: Cover component

62a: bend

71: Base material

72: Sleeve

73: Corrosion-resistant film

74: Plasma-resistant film

81,89: Sealing components

82: Installation components

S: Plasma generation space

Claims (16)

A shower head is used in a gas treatment device for applying gas treatment to a substrate, and supplies a corrosive treatment gas to a chamber in which the substrate is arranged. The shower head comprises: a base member; a shower plate having a plurality of gas discharge holes for discharging the treatment gas; a gas diffusion space, which is a portion disposed between the base member and the shower plate, into which the treatment gas is introduced and which is connected to the plurality of gas discharge holes. The base member and the shower plate are made of a metal substrate, and a portion of the base member facing the gas diffusion space and a portion of the shower plate facing the gas diffusion space and the gas discharge holes are made of a corrosion-resistant The base member is covered with a corrosion-resistant metal material or a corrosion-resistant film, the base member has a substrate made of aluminum or an aluminum-containing alloy, and a cover member made of the corrosion-resistant metal material and arranged in a manner covering the substrate at a portion facing the gas diffusion space, the base member is in contact with a portion of the spray plate that is further outside the gas diffusion space, and is fixed in a sealed state by a sealing member, and a bent portion that is bent in a state of not contacting the surface of the spray plate is formed at the end of the cover member, the sealing member contacts the corrosion-resistant film or corrosion-resistant material of the spray plate, and is maintained in a state of being pressed by the bent portion. The shower head as described in claim 1, wherein the corrosion-resistant metal material is composed of nickel-containing metal. For the sprinkler head described in claim 2, the nickel-containing metal is stainless steel or a nickel-based alloy. A shower head as described in claim 1 or 2, wherein the corrosion-resistant coating is a ceramic spray coating. The shower head described in claim 4, wherein the ceramic spray coating is an aluminum oxide spray coating. As described in claim 4, the above-mentioned ceramic spray coating is sealed with a sealing material composed of a synthetic resin. A shower head as described in any one of claims 1 to 3, wherein the base member comprises: a substrate made of aluminum or an aluminum-containing alloy and having a recess corresponding to the gas diffusion space, a corrosion-resistant film formed to cover the upper surface of the gas diffusion space of the substrate, and an annular member made of corrosion-resistant metal arranged to cover the side surface of the gas diffusion space of the substrate. A shower head as described in any one of claims 1 to 3, wherein the base member comprises: a substrate made of aluminum or an aluminum-containing alloy and having a recess corresponding to the gas diffusion space, a cover member made of the corrosion-resistant metal material and formed to cover the upper surface side of the gas diffusion space of the substrate, and an annular member made of corrosion-resistant metal and arranged to cover the side surface side of the gas diffusion space of the substrate. A shower head as described in claim 8, wherein the cover member and the annular member are formed as one body. The shower head as described in claim 7 further comprises a sealing member disposed between the annular member and the base member, and between the annular member and the shower plate. A shower head as recited in any one of claims 1 to 3, wherein the portion of the base member facing the gas diffusion space is covered with a corrosion-resistant film, the portion of the spray plate facing the gas diffusion space is covered with a corrosion-resistant film, the corrosion-resistant film on the side of the base member and the corrosion-resistant film on the side of the spray plate extend to a portion further outward from the gas diffusion space, and are in a state where they do not contact each other, and a sealing member is formed between the corrosion-resistant film on the side of the base member and the corrosion-resistant film on the side of the spray plate at a portion further outward from the gas diffusion space. A shower head as described in any one of claims 1 to 3, wherein the shower plate has a substrate made of aluminum or an aluminum-containing alloy, a corrosion-resistant film arranged to cover the substrate in a portion facing the gas diffusion space, and a plurality of sleeves embedded in the substrate and arranged to cover the plurality of gas discharge holes. A shower head as described in any one of claim items 1 to 3, wherein the shower plate has a substrate made of a corrosion-resistant metal material, and the substrate is exposed to the gas diffusion space and the gas discharge hole. The shower head as described in claim 13, wherein the base member has a substrate made of aluminum or an aluminum-containing alloy, and a cover member or a corrosion-resistant film made of the corrosion-resistant metal material arranged to cover the substrate at a portion facing the gas diffusion space, the cover member or the corrosion-resistant film extending to the outside of the gas diffusion space, and the sealing member is between the substrate of the shower plate and the cover member or the corrosion-resistant film at the outside of the gas diffusion space. A shower head as recited in any one of claims 1 to 3, wherein the gas treatment device is a plasma treatment device that generates plasma of the treatment gas in the chamber to perform plasma treatment, and the shower plate has a plasma-resistant film formed on the surface contacted by the plasma. A gas treatment device is used to perform gas treatment on a substrate, and the gas treatment device is characterized by comprising: a chamber for accommodating the substrate; a mounting table for mounting the substrate in the chamber; and a shower head as described in any one of claim 1 to claim 15, which is arranged in the chamber to face the mounting table and supply a corrosive treatment gas for generating plasma into the chamber.

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