Piping, semiconductor manufacturing equipment, and semiconductor manufacturing method

Abstract

To provide a piping capable of suppressing the blocking of an exhaust tube of a process gas, a semiconductor manufacturing device, and a method for manufacturing a semiconductor device.SOLUTION: A piping according to an embodiment exhausts a process gas from a processing chamber of a semiconductor manufacturing device. A first end part of a first tube part is connected to the processing chamber, and a second end part is connected to another piping. A second tube part is connected to the first tube part between the first end part and the second end part, and supplies a hydrogen gas or a hydrogen radical into the first tube part. A valve is provided between the second tube part and the second end part, and can open and close the inside of the first tube part. A metal film is coated on an inner wall of the first tube part.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This embodiment relates to piping, semiconductor manufacturing equipment, and a method for manufacturing semiconductor devices. [Background technology]

[0002] In semiconductor manufacturing equipment such as plasma CVD (Chemical Vapor Deposition) systems, there was a problem with the exhaust pipes of process gases becoming blocked. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2003-324096 [Patent Document 2] Japanese Patent Publication No. 2022-050230 [Patent Document 3] Japanese Patent Publication No. 2019-057530 [Patent Document 4] Japanese Patent Publication No. 2017-088916 [Patent Document 5] Japanese Patent Publication No. 2015-214746 [Overview of the Initiative] [Problems that the invention aims to solve]

[0004] The present invention provides piping, semiconductor manufacturing equipment, and a method for manufacturing semiconductor devices that can suppress blockage of process gas exhaust pipes. [Means for solving the problem]

[0005] The pipe according to this embodiment exhausts the process gas from the processing chamber of the semiconductor manufacturing apparatus. The first end of the first pipe portion is connected to the processing chamber, and the second end is connected to another pipe. The second pipe portion is connected to the first pipe portion between the first end and the second end, and supplies hydrogen gas or hydrogen radicals into the first pipe portion. The valve is provided between the second pipe portion and the second end, and can open and close the inside of the first pipe portion. A metal film is coated on the inner wall of the first pipe portion.

Brief Description of Drawings

[0006] [Figure 1] Schematic diagram showing a configuration example of a semiconductor manufacturing apparatus according to the first embodiment. [Figure 2] Schematic cross-sectional view showing an example of the configuration and function of a pipe. [Figure 3] Schematic cross-sectional view showing an example of the configuration and function of a pipe. [Figure 4] Schematic cross-sectional view showing an example of the configuration of a semiconductor manufacturing apparatus according to the second embodiment.

Mode for Carrying Out the Invention

[0007] Hereinafter, embodiments of the present invention will be described with reference to the drawings. This embodiment does not limit the present invention. The drawings are schematic or conceptual, and the ratios of each part are not necessarily the same as the actual ones. In the specification and drawings, the same reference numerals are given to the same elements as those described above with respect to the previous drawings, and the detailed description will be omitted as appropriate.

[0008] (First Embodiment) FIG. 1 is a schematic diagram showing a configuration example of a semiconductor manufacturing apparatus 1 according to the first embodiment. The semiconductor manufacturing apparatus 1 may be a film forming apparatus that processes a semiconductor substrate by plasmaizing and ionizing a process gas, such as plasma CVD (Chemical Vapor Deposition). Note that the semiconductor manufacturing apparatus 1 is also applicable to semiconductor manufacturing apparatuses other than plasma CVD apparatuses.

[0009] The semiconductor manufacturing apparatus 1 comprises a processing chamber 10, a stage 20, and piping 30.

[0010] The processing chamber 10 houses a semiconductor substrate (hereinafter also simply referred to as a wafer) W, and is used to deposit a material film on the wafer W by plasmaizing the process gas introduced inside. The stage 20 is provided inside the processing chamber 10 and can be used to place the wafer W on it. Although not shown in the figure, the processing chamber 10 is connected to piping for introducing gases such as process gas and purge gas.

[0011] The piping 30 is connected to the processing chamber 10 and is provided to exhaust the process gas used for processing the wafer W inside the processing chamber 10 to the outside. One end of the piping 30 is connected to the processing chamber 10, and the other end is connected to another piping 31. The configuration and function of the piping 30 will be described later.

[0012] The piping 30 is provided with a hydrogen supply pipe 40 and a valve 50. The hydrogen supply pipe 40 is connected between one end and the other end of the piping 30. One end of the hydrogen supply pipe 40 is connected to the piping 30 and is provided to supply hydrogen gas into the piping 30. The other end of the hydrogen supply pipe 40 is connected to a hydrogen supply unit 90 and introduces hydrogen gas from the hydrogen supply unit 90 into the piping 30. The hydrogen supply pipe 40 is connected to the piping 30 between the chamber 10 and the valve 50. The piping 30 converts the hydrogen gas from the hydrogen supply pipe 40 into hydrogen radicals and hydrogenates the process gas exhausted from the processing chamber 10.

[0013] Valve 50 is located between the hydrogen supply pipe 40 and the other end of the pipe 30, that is, downstream of the hydrogen supply pipe 40, and can open and close the inside of the pipe 30. For example, when valve 50 is open, the pipe 30 is open, and gas from the processing chamber 10 flows downstream from valve 50. Therefore, gas from the processing chamber 10 can be exhausted through pipe 30. When valve 50 is closed, pipe 30 is closed, and gas from the processing chamber 10 does not flow downstream from valve 50. Therefore, gas from the processing chamber 10 is not exhausted through pipe 30. Valve 50 is connected to valve control unit 51, and opens and closes the inside of pipe 30 under the control of valve control unit 51. Downstream indicates the direction of gas flow, and upstream indicates the opposite direction of gas flow.

[0014] The valve 50 can adjust the pressure inside the processing chamber 10 depending on the degree to which it is open or closed (the degree to which the piping 30 is opened). For example, when the valve 50 is slightly open (the degree to which the piping 30 is opened is small), the pressure inside the processing chamber 10 increases. On the other hand, when the valve 50 is wide open (the degree to which the piping 30 is opened is large), the pressure inside the processing chamber 10 decreases.

[0015] Piping 30 is connected between the processing chamber 10 and piping 31. Piping 31 is connected between piping 30 and the process gas recovery unit 60. Piping 32 is connected between the process gas recovery unit 60 and the vacuum pump 70. Piping 33 is connected between the vacuum pump 70 and the abatement device 80.

[0016] The process gas exhausted from the processing chamber 10 is hydrogenated by hydrogen radicals in the piping 30, and then cooled in the process gas recovery unit 60 via piping 31. The process gas recovery unit 60 cools and liquefies the hydrogenated process gas using, for example, liquid nitrogen. The liquefied process gas is recovered for reuse in the processing of the wafer W.

[0017] The gas that has passed through the process gas recovery unit 60 is sent to the abatement unit 80 via the piping 32 and the vacuum pump 70. The vacuum pump 70 is connected to the processing chamber 10 via the piping 30-32 and reduces the pressure inside the processing chamber 10.

[0018] The gas that has passed through the vacuum pump 70 is heated and rendered harmless in the abatement device 80 and then discharged to the outside.

[0019] The hydrogen supply unit 90 stores hydrogen and supplies hydrogen gas into the piping 30 via the hydrogen supply pipe 40.

[0020] The semiconductor manufacturing apparatus 1 includes a processing chamber 10 and piping 30, but the piping 30 is removable from the processing chamber 10 and can be replaced. Therefore, although the semiconductor manufacturing apparatus 1 includes at least a processing chamber 10, the components downstream of the piping 30, such as piping 30-33, process gas recovery unit 60, vacuum pump 70, abatement unit 80, and hydrogen supply unit 90, may be attached externally to the semiconductor manufacturing apparatus 1 as separate components.

[0021] Figures 2 and 3 are schematic cross-sectional views showing an example of the configuration and function of piping 30. Figure 2 shows hydrogen gas being supplied into piping 30. Figure 3 shows process gas being hydrogenated.

[0022] The piping 30 comprises a pipe section 30a, a hydrogen supply pipe 40, a valve 50, and a metal membrane 30b. The pipe section 30a has end E1 connected to the processing chamber 10 and end E2 connected to another pipe 31. The pipe section 30a is made of a corrosion-resistant material such as stainless steel (SUS) containing Fe, Ni, etc.

[0023] The hydrogen supply pipe 40 is connected in the middle of the piping 30 between end E1 and end E2, and can supply hydrogen gas into the piping 30. Similar to the pipe section 30a, the hydrogen supply pipe 40 is made of a corrosion-resistant material such as stainless steel (SUS) containing Fe, Ni, etc.

[0024] The valve 50 is provided between the hydrogen supply pipe 40 and the end E2, and is configured to be able to open or close the pipe 30. The valve 50 closes the pipe 30 by moving in the direction of arrow A1, and opens the pipe 30 by moving in the direction opposite to arrow A1. In FIG. 2, the valve 50 shows the state where the pipe 30 is open. For the valve 50 as well, similar to the pipe portion 30a, a corrosion-resistant material such as stainless steel (SUS) containing, for example, Fe, Ni, etc. is used.

[0025] The metal film 30b covers the inner wall of the pipe portion 30a. The metal film 30b is made of, for example, a material that hydrogenates hydrocarbon radicals to convert them into hydrogen carbonate gas. For the metal film 30b, for example, a single layer or a laminated film of any one of ruthenium (Rh), palladium (Pd), platinum (Pt), nickel (Ni), and iron (Fe) is used. The metal film 30b functions as a metal catalyst for hydrogenating the process gas.

[0026] For example, when hydrocarbon gas C m H n is used as the process gas, the hydrocarbon gas CmHn ionizes and radicalizes to generate a radical gas C m H n-p (hereinafter, also denoted as C m H n * ). Here, m and n are positive integers, and p is a positive integer less than or equal to n. Also, the radical gas C m H n * may sometimes be hereinafter also referred to as the process gas.

[0027] The radical gas C m H n * is used for the treatment of the wafer W, but there are also cases where it is exhausted without being used. In this case, the radical gas C m H n * flows into the pipe 30.

[0028] If the metal film 30b is not provided on the inner wall of the pipe section 30a, radical gas C m H n * It is adsorbed onto the inner wall of pipe section 30a and stabilized. When this is repeated, radical gas C m H n * Sediments (hydrocarbons) originating from this may clog pipe section 30a.

[0029] In particular, near valve 50, the flow of process gas changes, and the flow velocity of the process gas is prone to change. For example, when valve 50 is slightly open, the flow velocity of the process gas that has passed through valve 50 increases rapidly at the immediate downstream position of valve 50. In this case, deposits originating from the process gas are likely to adhere to the inner wall of pipe section 30a at the immediate downstream position of valve 50, making it prone to blockage.

[0030] In contrast, according to this embodiment, radical gas C m H n * A metal film 30b, which functions as a catalyst for hydrogenation, is provided on the inner wall of the pipe section 30a. The metal film 30b radicalizes the hydrogen gas from the hydrogen supply pipe 40 to generate hydrogen radicals. Radical gas C m H n * It reacts with hydrogen radicals to form hydrocarbon gas C m H n It is hydrogenated. The hydrocarbon gas is relatively stable and does not accumulate in the piping 30, but flows downstream. For example, as shown in Figure 3, radical gas C2H * When the radical gas C2H flows into the pipe 30, the metal film 30b acts as a catalyst, and the radical gas C2H * This is hydrogenated with hydrogen radicals. This produces the radical gas C2H * It becomes hydrocarbon gas C2H2 and flows downstream in a gaseous state without accumulating in the pipe 30.

[0031] A catalyst that hydrogenates hydrocarbon radicals is used in the metal film 30b. For example, the metal film 30b may be a single layer or a multilayer film of two or more of the following materials: ruthenium (Rh), palladium (Pd), platinum (Pt), nickel (Ni), or iron (Fe).

[0032] Furthermore, as an example of a process gas, hydrocarbon gas C m H n While the above examples were given, any material that can be hydrogenated into a gas can be used as a process gas. For example, the main component of the process gas may be any of boron (B), carbon (C), silicon (Si), phosphorus (P), sulfur (S), germanium (Ge), or arsenic (As).

[0033] For example, if the process gas is a gas containing boron (B) (such as B2H6, BF3, or BCl3), boron nitride (BN), boron carbide (BC), and boron-containing B-doped SiO2 tend to accumulate as by-products. However, according to this embodiment, the metal film 30b hydrogenates these process gases and by-products, causing them to be discharged as process gas B2H6 or the like.

[0034] The process gas is a gas containing carbon (C) (CH4, C2H6, C3H8, C4H 10 If it is C2H4, C3H6, C4H8, C2H2, C3H4, C4H6, CF4, C4F6, C4F8), then carbon, C x F y (x, y are positive integers), etc., tend to deposit as by-products. However, according to this embodiment, the metal film 30b hydrogenates these process gases and by-products, thereby reducing the amount of process gases CH4, C2H6, C3H8, C4H 10 These are emitted as C2H4, C3H6, C4H8, C2H2, C3H4, C4H6, etc.

[0035] When the process gas is a silicon (Si)-containing gas such as SiH4, Si2H6, or SiF4, silicon, silicon oxides, silicon nitrides, etc. tend to deposit as byproducts. However, according to this embodiment, the metal film 30b hydrogenates these process gases and byproducts, thereby reducing the process gas SiH 4、 It is emitted as Si2H6, etc.

[0036] When the process gas is a phosphorus (P)-containing gas (PH3), P-doped Si or P-doped SiO2, etc., tend to accumulate as by-products. However, according to this embodiment, the metal film 30b hydrogenates these process gases and by-products, so that they are discharged as process gas (PH3, etc.).

[0037] When the process gas is arsenic-containing gas AsH3, As-doped Si or As-doped SiO2, etc., tend to accumulate as by-products. However, according to this embodiment, the metal film 30b hydrogenates these process gases and by-products, so that they are discharged as process gas AsH3, etc.

[0038] Thus, even if the main component of the process gas is any of boron (B), carbon (C), silicon (Si), phosphorus (P), sulfur (S), germanium (Ge), or arsenic (As), the metal film 30b can hydrogenate the process gas and discharge it as a gas.

[0039] As a result, in this embodiment, the process gas does not accumulate on the inner wall of the piping 30, and flows downstream through the piping 30 and valve 50 while remaining in a gaseous state. For example, even near valve 50, no deposits originating from the process gas adhere, making blockage unlikely.

[0040] Preferably, the flow rate of hydrogen gas supplied from the hydrogen supply pipe 40 is greater than the flow rate of process gas supplied to the chamber 10. This ensures that the exhausted process gas is sufficiently hydrogenated.

[0041] Furthermore, in the process gas recovery unit 60, liquid nitrogen cools and liquefies the hydrogenated process gas. For example, process gases such as CH4, C3H6, C2H2, B2H6, SiH4, PH3, and AsH4 have higher boiling points than nitrogen, so they can be liquefied and recovered in the process gas recovery unit 60. The recovered process gas can be reused for processing the wafer W.

[0042] The gas that has passed through the process gas recovery unit 60 and the vacuum pump 70 is burned and rendered harmless in the abatement unit 80 and then discharged to the outside. In this embodiment, the metal film 30b covers the inner wall of pipe 30. However, the metal film 30b may also cover the inner walls of other pipes 31 to 33. This also suppresses blockage of pipes 31 to 33. Furthermore, by providing the metal film 30b on the inner wall of pipe 31, more process gas is hydrogenated. Consequently, the process gas recovery unit 60 can recover more process gas.

[0043] (Method of manufacturing semiconductor devices) In the semiconductor device manufacturing method using the semiconductor manufacturing apparatus 1 according to this embodiment, first, a wafer W is brought into the processing chamber 10 and placed on the stage 20.

[0044] Next, a process gas is introduced into the processing chamber 10 to process the wafer W. This allows, for example, a desired material film to be formed on the surface of the wafer W.

[0045] After processing the wafer W, the used process gas is exhausted from the processing chamber 10 into the piping 30. At this time, the hydrogen adsorbed on the metal film 30b becomes hydrogen radicals and hydrogenates the process gas. Preferably, the flow rate of hydrogen gas supplied from the hydrogen supply pipe 40 is greater than the flow rate of process gas supplied to the chamber 10. This ensures that the exhausted process gas is sufficiently hydrogenated.

[0046] Subsequently, this hydrogenated process gas is either recovered by the process gas recovery unit 60 or detoxified by the pollution control unit 80 and discharged to the outside.

[0047] As a result, the process gas does not accumulate on the inner wall of the pipe 30, but is hydrogenated and flows downstream through the pipe 30 and valve 50 in a gaseous state. Consequently, deposits originating from the process gas do not adhere to the pipe 30, and blockage of the pipe 30 can be suppressed.

[0048] (Second Embodiment) Figure 4 is a schematic cross-sectional view showing an example of the configuration of a semiconductor manufacturing apparatus according to the second embodiment. In the second embodiment, the metal film 30b is not provided, and instead, a hydrogen radical generator 95 is connected to the piping 40. The hydrogen radical generator 95 receives hydrogen gas H2 from the hydrogen supply unit 90 and ionizes it with plasma to produce hydrogen radicals 30c (for example, H2). * This device generates hydrogen radicals. The hydrogen radicals 30c generated in the hydrogen supply unit 90 are supplied into the pipe 30 from the pipe 40. Since the hydrogen radical generator 95 supplies hydrogen radicals into the pipe 30, the metal film 30b, which functions as a catalyst, is not required.

[0049] Other configurations of the second embodiment may be the same as the corresponding configurations of the first embodiment. As in the second embodiment, hydrogen radicals 30c may be generated outside the piping 30 and supplied into the piping 30. Even in this case, the process gas exhausted into the piping 30 is hydrogenated and flows downstream through the piping 30 in a gaseous state. As a result, deposits originating from the process gas do not adhere to the piping 30, and blockage of the piping 30 can be suppressed.

[0050] The method for manufacturing a semiconductor device according to the second embodiment differs from the first embodiment in that a hydrogen radical generator 95 generates hydrogen radicals 30c outside the piping 30 and supplies them into the piping 30. However, the other steps in the second embodiment may be the same as those in the first embodiment. Therefore, the second embodiment can obtain the same effects as the first embodiment.

[0051] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]

[0052] 1 Semiconductor manufacturing equipment, 10 Processing chamber, 20 Stage, 30 Piping, 30a Pipe section, 30b Metal film, 40 Hydrogen supply pipe, 50 Valve, 95 Hydrogen radical generator

Claims

1. A processing chamber for processing substrates with process gas, A first pipe section, the first end of which is connected to the processing chamber and the second end of which is connected to other piping, exhausts process gas from the processing chamber. A second pipe section is connected to the first pipe section between the first end and the second end, and supplies hydrogen gas into the first pipe section. A valve is provided between the second pipe section and the second end section, and is capable of opening and closing the inside of the first pipe section, The first pipe section comprises a metal film covering the inner wall, The aforementioned metal film is a single layer or a multilayer film of two or more of the following: ruthenium (Rh), palladium (Pd), platinum (Pt), nickel (Ni), or iron (Fe), and a material that hydrogenates radicals is used. A semiconductor manufacturing apparatus in which the flow rate of hydrogen gas supplied from the second pipe section is greater than the flow rate of the process gas.

2. A method for manufacturing a semiconductor device using a semiconductor manufacturing apparatus, comprising: a processing chamber for processing a substrate with a process gas; a first pipe section having a first end connected to the processing chamber and a second end connected to other piping for exhausting the process gas from the processing chamber; a second pipe section connected to the first pipe section between the first end and the second end for supplying hydrogen gas into the first pipe section; a valve provided between the second pipe section and the second end, capable of opening and closing the inside of the first pipe section; and a metal film covering the inner wall of the first pipe section, wherein the metal film is a single layer or a multilayer film of two or more of ruthenium (Rh), palladium (Pd), platinum (Pt), nickel (Ni), or iron (Fe), and a material that hydrogenates radicals is used, wherein The substrate is processed by introducing a process gas into the processing chamber. A method for manufacturing a semiconductor device, comprising supplying hydrogen gas or hydrogen radicals into a first pipe section connected to a second pipe section at a flow rate greater than the flow rate of the process gas, in a first pipe section that exhausts process gas from the processing chamber, thereby hydrogenating the process gas.

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