Method for processing semiconductor substrates

Abstract

The present invention provides a semiconductor substrate processing method that can suppress the accumulation of unintended silver-containing particles in the chamber during the processing of the semiconductor substrate. [Solution] This semiconductor substrate processing method comprises the steps of: preparing a substrate processing apparatus 100 equipped with a chamber 10 for processing a semiconductor substrate 200; preparing an ozone gas supply source 21 for supplying ozone gas; connecting a fitting 50 and pipes 41-45, whose threaded portions 50d are silver-plated, while applying frictional force to the threaded portions 50d, thereby connecting the chamber 10 and the ozone gas supply source 21; supplying ozone gas from the ozone gas supply source 21 to the fitting 50 and pipes 41-45 to remove silver-containing particles originating from the silver plating present in the fitting 50 and pipes 41-45; and placing the semiconductor substrate 200 in the chamber 10 and processing the semiconductor substrate 200.

Description

Technical Field

[0001] This invention relates to a method for processing a semiconductor substrate.

Background Art

[0002] Conventionally, a substrate processing apparatus has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a substrate processing apparatus that places a semiconductor substrate in a chamber and supplies a processing gas into the chamber through a pipe to process the semiconductor substrate. In the substrate processing apparatus of Patent Document 1, ozone gas is supplied into the chamber as the processing gas.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a conventional substrate processing apparatus that uses ozone gas as in Patent Document 1, particles containing silver unintentionally may remain in the chamber during the processing of the semiconductor substrate. Therefore, it is desired to suppress the retention of particles containing silver unintentionally in the chamber during the processing of the semiconductor substrate.

[0006] This invention has been made to solve the above problems, and one object of this invention is to provide a method for processing a semiconductor substrate capable of suppressing the retention of particles containing silver unintentionally in the chamber during the processing of the semiconductor substrate.

Means for Solving the Problems

[0007] To achieve the above objective, a semiconductor substrate processing method according to one aspect of the present invention comprises the steps of: preparing a substrate processing apparatus equipped with a chamber for processing a semiconductor substrate; preparing an ozone gas supply source for supplying ozone gas; connecting a joint and a piping section, whose screw portions are silver-plated, while applying frictional force to the screw portions, thereby connecting the chamber and the ozone gas supply source; supplying ozone gas from the ozone gas supply source to the joint and the piping section to remove silver-containing particles originating from the silver plating present in the joint and the piping section; and arranging a semiconductor substrate in the chamber for processing the semiconductor substrate.

[0008] In one aspect of this invention, a semiconductor substrate processing method is provided, as described above, which involves supplying ozone gas from an ozone gas supply source to the joint and piping sections to remove silver-containing particles originating from silver plating present in the joint and piping sections. This allows the silver-containing particles originating from silver plating present in the joint and piping sections to be converted into silver oxide, which has a lower surface energy and lower adhesion than silver. As a result, the silver-containing particles in the joint and piping sections can be converted into silver oxide and discharged outside the substrate processing apparatus. This allows the processing of the semiconductor substrate to begin only after removing the silver-containing particles adhering to the joint and piping sections, even when ozone gas is used for processing the semiconductor substrate. Consequently, it is possible to suppress the accumulation of unintended silver-containing particles in the chamber during the processing of the semiconductor substrate and their adhesion to the surface of the semiconductor substrate. Unintended silver-containing particles are particles (particles) containing at least one of elemental silver and silver-containing compounds (silver oxides, silver alloys, etc.).

[0009] In the semiconductor substrate processing method according to the first aspect described above, preferably, the process is characterized by repeating the following steps: placing a test substrate in a chamber and processing the test substrate before processing the semiconductor substrate; weighing the amount of silver-containing particles on the processed surface of the test substrate; supplying ozone gas from an ozone gas supply source to the joint and piping sections until the amount of silver-containing particles falls below a threshold; placing a test substrate in the chamber and processing the test substrate; and weighing the amount of silver-containing particles on the processed surface of the test substrate. With this configuration, the amount of silver-containing particles can be weighed using the test substrate, and the actual semiconductor substrate can be processed only after the amount of silver-containing particles falls below a threshold. This allows for confirmation that the amount of silver flowing into the chamber has decreased sufficiently before starting the semiconductor substrate processing.

[0010] In the semiconductor substrate processing method according to the first aspect described above, preferably, an exhaust pipe for exhausting ozone gas is provided between the joint and piping section and the chamber, and a valve is provided between the exhaust pipe section and the chamber. With the valve closed, ozone gas is supplied to the joint and piping section from an ozone gas supply source to discharge silver-containing particles in the joint and piping section to the exhaust pipe section. With this configuration, the silver derived from the silver plating of the joint and piping section can be oxidized by the ozone gas and discharged from the exhaust pipe section, thereby effectively suppressing the inflow of silver-containing particles into the chamber.

[0011] In this case, preferably, a metering unit is provided in the exhaust pipe section to measure silver-containing particles contained in the gas flowing inside the joint section and the piping section. The process includes the steps of supplying ozone gas from an ozone gas supply source to the joint section, the piping section, and the exhaust pipe section with the metering unit activated, and stopping the supply of ozone gas from the ozone gas supply source and opening the valve after the amount of silver-containing particles measured by the metering unit falls below a threshold. With this configuration, it is possible to oxidize and discharge silver with ozone gas until the amount of silver-containing particles originating from the silver plating of the joint section and the piping section discharged falls below a threshold. As a result, after confirming that the amount of silver flowing into the chamber has decreased sufficiently, the processing of the semiconductor substrate can be started.

[0012] In the semiconductor substrate processing method according to the first aspect described above, preferably, a metering unit for measuring silver-containing particles contained in the gas flowing inside the joint and piping is provided downstream of the joint and piping, and / or in the chamber, and the semiconductor substrate is not placed in the chamber, and ozone gas is supplied to the joint and piping from an ozone gas supply source while the metering unit is activated, and the supply of ozone gas from the ozone gas supply source is stopped after the amount of silver-containing particles measured by the metering unit falls below a threshold. With this configuration, the metering unit provided downstream of the joint and piping, and / or in the chamber, measures the silver oxide oxidized by the ozone gas, and the silver is oxidized and discharged with ozone gas until the amount of silver-containing particles generated from the silver plating of the joint and piping falls below a threshold. As a result, after confirming that the amount of silver flowing into the chamber has decreased sufficiently, the processing of the semiconductor substrate can be started.

[0013] In the semiconductor substrate processing method according to the first aspect described above, preferably, in the step of processing the semiconductor substrate, ozone gas is supplied to the chamber from an ozone gas supply source. With this configuration, the ozone gas supply source used for processing the semiconductor substrate can also be used for removing silver-containing particles generated in the joints and piping. This makes it possible to remove silver-containing particles generated in the joints and piping without requiring special equipment.

[0014] In this case, preferably, a solvent supply source for supplying the solvent, a solvent piping section connected to the solvent supply source for the flow of the solvent, and a mixing section between the joint and piping section and the chamber to which the solvent piping section is connected are provided, and in the process of processing the semiconductor substrate, the ozone gas and solvent are mixed in the mixing section and supplied to the chamber. With this configuration, the equipment for supplying the solvent containing dissolved ozone gas used for processing the semiconductor substrate can be used to remove silver-containing particles generated in the joint and piping section. This makes it possible to remove silver-containing particles generated in the joint and piping section without requiring special equipment.

[0015] In the process of processing the semiconductor substrate described above, in the mixing section, ozone gas and a solvent are mixed and supplied to the chamber, preferably the solvent is pure water. With this configuration, the process of removing silver-containing particles generated in the joints and piping can be carried out using equipment for supplying ozonated water, which is obtained by dissolving ozone gas used for processing the semiconductor substrate in pure water. This makes it possible to remove silver-containing particles generated in the joints and piping without requiring special equipment. [Effects of the Invention]

[0016] According to the present invention, as described above, it is possible to suppress the accumulation of unintended silver-containing particles in the chamber during the processing of semiconductor substrates. [Brief explanation of the drawing]

[0017] [Figure 1] It is a schematic diagram showing a substrate processing apparatus according to the first embodiment. [Figure 2] It is a cross-sectional view showing an example of a joint of the substrate processing apparatus according to the first embodiment. [Figure 3] It is a diagram for explaining a silver removal method of the substrate processing apparatus according to the first embodiment. [Figure 4] It is a diagram for explaining the processing of a test substrate of the substrate processing apparatus according to the first embodiment. [Figure 5] It is a flowchart for explaining the procedure of a semiconductor substrate processing method of the substrate processing apparatus according to the first embodiment. [Figure 6] It is a schematic diagram showing a substrate processing apparatus according to the second embodiment. [Figure 7] It is a flowchart for explaining the procedure of a semiconductor substrate processing method of the substrate processing apparatus according to the second embodiment. [Figure 8] It is a schematic diagram showing a substrate processing apparatus according to the third embodiment.

Mode for Carrying Out the Invention

[0018] Hereinafter, embodiments of the present invention will be described based on the drawings.

[0019] (First Embodiment) Referring to FIGS. 1 to 4, the configuration of a substrate processing apparatus 100 according to the first embodiment of the present invention will be described.

[0020] The substrate processing apparatus 100 according to the first embodiment is an apparatus that performs processing on a semiconductor substrate 200 to be processed. For example, the substrate processing apparatus 100 performs a process of etching the semiconductor substrate 200, a process of forming a film on the semiconductor substrate 200, or a process of forming a circuit pattern on the semiconductor substrate 200. The substrate processing apparatus 100 also performs processing on the semiconductor substrate 200 using a processing gas. The substrate processing apparatus 100 also performs processing by applying a voltage to the semiconductor substrate 200. The semiconductor substrate 200 is a semiconductor wafer formed from materials such as silicon oxide, silicon, quartz glass, borosilicate glass, silicon carbide, gallium arsenide, and sapphire.

[0021] As shown in Figure 1, the substrate processing apparatus 100 includes a chamber 10 in which the semiconductor substrate 200 to be processed is placed, an ozone gas supply source 21 that supplies ozone gas to the chamber 10, processing gas supply units 22, 23, and 24 that supply processing gas other than ozone gas to the chamber 10, and an exhaust device 30 that discharges the gas inside the chamber 10. The substrate processing apparatus 100 also includes a voltage supply unit (not shown) that applies voltage to the semiconductor substrate 200.

[0022] Furthermore, the substrate processing apparatus 100 includes pipes 41, 42, 43, 44, and 45 for supplying processing gas into the chamber 10. Note that pipes 41 to 45 are examples of the "piping section" as defined in the claims.

[0023] Chamber 10 has an internal sealed space that contains the supplied processing gas. Chamber 10 also has an internal mounting section on which the semiconductor substrate 200 to be processed is placed. Furthermore, Chamber 10 is configured to be openable for inserting and removing the semiconductor substrate 200.

[0024] The ozone gas supply source 21 generates ozone gas to be supplied into the chamber 10. The ozone gas generated by the ozone gas supply source 21 is supplied into the chamber 10 via pipes 41 and 45. The ozone gas supply source 21 is configured to generate ozone gas containing ozone (O3) from a source gas (a gas containing oxygen (O2)). The ozone gas supply source 21 is configured to introduce the source gas between dielectrics provided with electrodes, apply an AC voltage, and generate ozone by dielectric barrier discharge. The ozone gas supply source 21 has a flow rate of, for example, 100-300 g / m³. 3 The system is configured to produce ozone gas with an ozone concentration of approximately (N). The ozone gas supply source 21 is also configured to produce ozone gas with an ozone concentration of approximately 5% to 20% by volume.

[0025] The processing gas supply units 22, 23, and 24 supply processing gas into the chamber 10 when processing the semiconductor substrate 200. The processing gas supply units 22, 23, and 24 supply different processing gases to each other. In the example shown in Figure 1, three processing gas supply units 22, 23, and 24 are shown, but there may be two or fewer, or four or more. The processing gas supply units 22, 23, and 24 supply processing gases such as fluoride compound gases (CF-based gases such as CF4, SF6, etc.), chlorine compound gases, nitrogen compound gases, silicon-based gases, ammonia gas, oxygen gas, hydrogen gas, nitrogen gas, argon gas, helium gas, and water vapor gas. The processing gases supplied from the processing gas supply units 22, 23, and 24 are not limited to the gases listed above and are set according to the processing to be performed on the semiconductor substrate 200.

[0026] The processing gas supply units 22, 23, and 24 are filled with, for example, compressed or liquefied processing gas. The processing gas supplied from processing gas supply unit 22 is supplied into the chamber 10 via piping 42 and 45. The processing gas supplied from processing gas supply unit 23 is supplied into the chamber 10 via piping 43 and 45. The processing gas supplied from processing gas supply unit 24 is supplied into the chamber 10 via piping 44 and 45.

[0027] The exhaust system 30 reduces the pressure inside the chamber 10. The exhaust system 30 includes a vacuum pump for exhausting the gas inside the chamber 10 and an exhaust pipe connecting the vacuum pump and the chamber 10. The exhaust system 30 exhausts the gas inside the chamber 10 via the exhaust pipe using the vacuum pump, bringing the inside of the chamber 10 to a predetermined pressure state close to a vacuum.

[0028] The pipes 41-45 are provided for introducing the processed gas into the chamber 10. The pipes 41-45 are assembled by connecting them with fittings 50 (fittings 51-57). Specifically, pipe 41 is formed by connecting multiple pipe members with fittings 51. Pipe 42 is formed by connecting multiple pipe members with fittings 52. Pipe 43 is formed by connecting multiple pipe members with fittings 53. Pipe 44 is formed by connecting multiple pipe members with fittings 54. Pipes 41 and 42 are connected to each other with fittings 55. Pipes 41 and 42 are connected to pipe 45 with fittings 56. Pipes 43 and 44 are connected to each other with fittings 57. Pipes 43 and 44 are connected to pipe 45 with fittings 56. Fittings 50-57 are examples of the "fittings" in the claims. The type of fitting 50 (fittings 51-57) is selected appropriately depending on the structure of the piping 41-45 being assembled. Sometimes fittings of the same structure are used, and sometimes multiple different types of fittings are used.

[0029] A valve 41a is provided in the piping 41. By opening and closing the valve 41a, the supply / stop of ozone gas from the ozone gas supply source 21 is switched. In other words, when the valve 41a is opened, ozone gas is supplied from the ozone gas supply source 21. On the other hand, when the valve 41a is closed, the supply of ozone gas from the ozone gas supply source 21 is stopped. In addition, the flow rate of ozone gas supplied from the ozone gas supply source 21 is adjusted by adjusting the opening degree of the valve 41a.

[0030] Valves 42a and 421b are provided in the piping 42. An exhaust pipe section 42b is also provided in the piping 42. By opening and closing valve 42a, the supply / stop of the processing gas supplied from the processing gas supply unit 22 is switched. That is, when valve 42a is opened, processing gas is supplied from the processing gas supply unit 22. On the other hand, when valve 42a is closed, the supply of processing gas from the processing gas supply unit 22 is stopped. Also, by adjusting the opening degree of valve 42a, the flow rate of the processing gas supplied from the processing gas supply unit 22 is adjusted. Valve 421b is used when removing silver in the piping 42 from the exhaust pipe section 42b using ozone gas. That is, as shown in Figure 3, when removing silver in the piping 42 with ozone gas supplied from the ozone gas supply source 21, ozone gas flows through the piping 42 by opening valves 42a and 421b. The exhaust pipe section 42b is provided between the processing gas supply unit 22 and the joint 52.

[0031] The piping 43 is equipped with valves 43a and 431b. The piping 43 is also equipped with an exhaust pipe section 43b. By opening and closing valve 43a, the supply / stop of the processing gas supplied from the processing gas supply unit 23 is switched. In other words, when valve 43a is opened, processing gas is supplied from the processing gas supply unit 23. On the other hand, when valve 43a is closed, the supply of processing gas from the processing gas supply unit 23 is stopped. Furthermore, by adjusting the opening degree of valve 43a, the flow rate of the processing gas supplied from the processing gas supply unit 23 is adjusted. Valve 431b is used when removing silver in the piping 43 from the exhaust pipe section 43b using ozone gas. In other words, as shown in Figure 3, when removing silver in the piping 43 with ozone gas supplied from the ozone gas supply source 21, ozone gas flows through the piping 43 by opening valves 43a and 431b. The exhaust pipe section 43b is provided between the processing gas supply unit 23 and the joint 53.

[0032] The piping 44 is equipped with valves 44a and 441b. The piping 44 is also equipped with an exhaust pipe section 44b. By opening and closing valve 44a, the supply / stop of the processing gas supplied from the processing gas supply unit 24 is switched. In other words, when valve 44a is opened, processing gas is supplied from the processing gas supply unit 24. On the other hand, when valve 44a is closed, the supply of processing gas from the processing gas supply unit 24 is stopped. Furthermore, by adjusting the opening degree of valve 44a, the flow rate of the processing gas supplied from the processing gas supply unit 24 is adjusted. Valve 441b is used when removing silver in the piping 44 from the exhaust pipe section 44b using ozone gas. In other words, as shown in Figure 3, when removing silver in the piping 44 with ozone gas supplied from the ozone gas supply source 21, ozone gas flows through the piping 44 by opening valves 44a and 441b. The exhaust pipe section 44b is provided between the processing gas supply unit 24 and the joint 54.

[0033] The piping 45 is provided with valves 45a and 451b. The piping 45 is also provided with an exhaust pipe section 45b. Valves 45a and 451b are used to remove silver from the piping 41-45 using ozone gas from the exhaust pipe section 45b. In other words, as shown in Figure 3, when removing silver from the piping 41-45 using ozone gas supplied from the ozone gas supply source 21, valve 451b is opened and valve 45a is closed, allowing the ozone gas to flow through the piping 41-45 before being discharged from the exhaust pipe section 45b. The exhaust pipe section 45b is provided between the joints 51-57 and the piping 41-44 and the chamber 10. Valve 45a is provided between the exhaust pipe section 45b and the chamber 10. Note that valve 45a is an example of a "valve" as defined in the claims.

[0034] The joints 50 (joints 51-57) are provided to connect multiple pipe members of the pipes 41-45. As shown in Figure 2, the joints 50 (joints 51-57) include a first member 50a, a second member 50b, and a gasket 50c. The first member 50a and the second member 50b are connected by screwing in the threaded portion 50d. In other words, the threaded portion 50d is fastened to each other by applying frictional force between the female thread formed on the first member 50a and the male thread formed on the second member 50b. In addition, at least one of the female and male threads of the threaded portion 50d is silver-plated to prevent seizing and galling. Galling is a phenomenon in which the female and male threads seize and become fixed due to frictional heat during fastening. During fastening, friction between the male and female threads causes some of the silver plating to peel off, adhering to the inner walls of pipes 41-45 and fittings 50 (51-57), forming silver-containing particles. These silver-containing particles peel off during processing of the semiconductor substrate 200 and are carried into the chamber 10 by the flow of ozone gas or processing gas. The adhesion of silver-containing particles to the surface of the semiconductor substrate 200 during processing in the chamber 10 can cause defects in the semiconductor substrate 200.

[0035] In this embodiment, in order to prevent unintended silver-containing particles from accumulating in the chamber 10 during the processing of the semiconductor substrate 200, a process is performed to remove silver from the pipes 41-45 and fittings 50 (fittings 51-57) before processing the semiconductor substrate 200. Furthermore, the semiconductor substrate 200 processing method of this embodiment comprises the steps of: preparing a substrate processing apparatus 100 equipped with a chamber 10 for processing the semiconductor substrate 200; preparing an ozone gas supply source 21 for supplying ozone gas; connecting fittings 50 (fittings 51-57) and pipes 41-45, whose threaded portions 50d are silver-plated, while applying frictional force to the threaded portions 50d, thereby connecting the chamber 10 and the ozone gas supply source 21; supplying ozone gas from the ozone gas supply source 21 to the fittings 50 and pipes 41-45 to remove silver-containing particles originating from the silver plating present in the fittings 50 and pipes 41-45; and placing the semiconductor substrate 200 in the chamber 10 and processing the semiconductor substrate 200.

[0036] Here, silver (Ag) has a relatively high 1250 mJ / m³ 2 It has a surface energy of 200 mJ / m². Therefore, when silver (Ag) is not oxidized, it has a high surface energy, resulting in strong adhesion to the inner walls of pipes 41-45, the inner walls of fittings 50 (fittings 51-57), and the structures inside chamber 10. Oxidized silver oxide (Ag2O, Ag2O2, Ag2O3) has a surface energy of 200 mJ / m². 2As a result, the adhesion strength decreases. Also, silver (Ag) has a relatively high oxidation-reduction potential of +0.80V. Therefore, when silver (Ag) attached to the inside of pipes 41-45, fittings 50 (fittings 51-57), and chamber 10 is oxidized by a substance with strong oxidizing power (oxidation-reduction potential: +2.07V) such as ozone (O3), it becomes silver oxide (Ag2O, Ag2O2, Ag2O3) and peels off from the inside of pipes 41-45, fittings 50 (fittings 51-57), and chamber 10. In other words, by circulating ozone gas through the inside of pipes 41-45, fittings 50 (fittings 51-57), and chamber 10 before processing the semiconductor substrate 200, the silver (Ag) attached to the inside of pipes 41-45, fittings 50 (fittings 51-57), and chamber 10 is removed.

[0037] In the oxidation process, the silver that has adhered to the inner walls of pipes 41-45 and fittings 50 (fittings 51-57) due to the silver plating on fittings 50 (51-57) of pipes 41-45 is oxidized with ozone gas.

[0038] The oxidation process and the discharge process are performed after connecting the pipes 41-45 and before starting the processing of the semiconductor substrate 200. For example, when installing the substrate processing apparatus 100 in a facility such as a factory, the process to remove silver (oxidation process and discharge process) is performed after connecting and assembling the pipes 41-45. Also, if the pipes 41-45 are removed and then reassembled for maintenance or replacement, the process to remove silver (oxidation process and discharge process) is performed after connecting and assembling the pipes 41-45.

[0039] In the oxidation process, ozone gas is supplied to piping that includes piping 41 for supplying ozone gas when processing the semiconductor substrate 200, and piping 42, 43, and 44 for supplying processing gases other than ozone gas when processing the semiconductor substrate 200. Specifically, as shown in Figure 3, ozone gas is supplied from the ozone gas supply source 21 with valves 41a, 42a, 421b, 43a, 431b, 44a, 441b, and 451b open. As a result, the ozone gas supplied from the ozone gas supply source 21 is supplied to piping 41-45 and fittings 50 (51-57).

[0040] Furthermore, the semiconductor substrate 200 processing method of this embodiment involves the following steps before processing the semiconductor substrate 200: placing a test substrate 200a (see Figure 4) in the chamber 10 and processing the test substrate 200a; weighing the silver-containing particles on the processed surface of the test substrate 200a; supplying ozone gas from the ozone gas supply source 21 to the fittings 50 (fittings 51-57) and pipes 41-45 until the amount of silver-containing particles falls below a threshold; and repeating the process of placing the test substrate 200a in the chamber 10 and processing the test substrate 200a, and weighing the silver-containing particles on the processed surface of the test substrate 200a. For example, in the process of processing the test substrate 200a, ozone gas is supplied from the ozone gas supply source 21 to the chamber 10, and the test substrate 200a is processed by the ozone gas. Furthermore, in the process of processing the test substrate 200a, processing gas is supplied to the chamber 10 from the processing gas supply units 22-24, and the test substrate 200a is processed by the processing gas.

[0041] Next, with reference to Figure 5, the procedure for processing the semiconductor substrate 200 using the substrate processing apparatus will be described.

[0042] In step S1 of Figure 5, the substrate processing apparatus 100 is prepared. Specifically, the substrate processing apparatus 100, which includes the chamber 10, is transported to an installation location such as a factory and installed.

[0043] In step S2, the ozone gas supply source 21 is prepared. Specifically, the ozone gas supply source 21 is transported to the installation location, such as inside the factory, and installed. The processing gas supply units 22 to 24 are prepared in the same manner. Note that steps S1 and S2 can be performed in any order, or they can be performed simultaneously.

[0044] In step S3, the chamber 10 is connected to the ozone gas supply source 21. The chamber 10 is also connected to the processing gas supply units 22-24. Specifically, the pipes 41-45 are connected by connecting the fittings 51-57. This connects the chamber 10 to the ozone gas supply source 21 and the processing gas supply units 22-24. Step S3 includes cases where a new substrate processing apparatus 100 is installed, where an existing substrate processing apparatus 100 is maintained or partially replaced, or where parts of an existing substrate processing apparatus 100 are reduced, added, or modified.

[0045] In step S4, silver-containing particles are oxidized and removed by ozone gas. Specifically, ozone gas is supplied from the ozone gas source 21 to the pipes 41-45. As a result, the silver (Ag) present in the pipes 41-45 and the fittings 51-57 is oxidized to silver oxide (Ag2O, Ag2O2, Ag2O3).

[0046] In step S5, the test substrate 200a is placed in the chamber 10 and processing is performed on the test substrate 200a.

[0047] In step S6, the test substrate 200a is removed from the chamber 10, and the silver-containing particles on the test substrate 200a are weighed. For example, the surface of the test substrate 200a is observed using a microscope or the like, and the number of particles per unit area is weighed.

[0048] In step S7, it is determined whether the amount of silver-containing particles in the weighed test substrate 200a is below a predetermined threshold. If the amount of particles is above the predetermined threshold, the process returns to step S4 and steps S4 to S7 are repeated. If the amount of particles is below the predetermined threshold, the process proceeds to step S8. The predetermined threshold can be arbitrarily set and changed by the user of the substrate processing device 100 according to the purpose of using the substrate processing device 100.

[0049] In step S8, the semiconductor substrate 200 is placed in the chamber 10 and processed.

[0050] (Effects of the first embodiment) In the first embodiment, the following effects can be obtained.

[0051] In this embodiment, as described above, the semiconductor substrate 200 processing method includes a step of supplying ozone gas from an ozone gas supply source 21 to the joints 50 (joints 51-57) and pipes 41-45 to remove silver-containing particles originating from silver plating present in the joints 50 (joints 51-57) and pipes 41-45. This allows the silver-containing particles originating from silver plating present in the joints 50 (joints 51-57) and pipes 41-45 to be converted into silver oxide, which has a lower surface energy and lower adhesion than silver. As a result, the silver-containing particles in the joints 50 (joints 51-57) and pipes 41-45 can be converted into silver oxide and discharged outside the substrate processing apparatus 100. Therefore, even when ozone gas is used to process the semiconductor substrate 200, processing of the semiconductor substrate 200 can be started after removing the silver-containing particles attached to the joints 50 (joints 51-57) and pipes 41-45. As a result, it is possible to suppress the accumulation of unintended silver-containing particles in the chamber 10 during the processing of the semiconductor substrate 200 and their adhesion to the surface of the semiconductor substrate 200.

[0052] Furthermore, in this embodiment, as described above, before the process of processing the semiconductor substrate 200, the following steps are repeated: placing the test substrate 200a in the chamber 10 and processing the test substrate 200a; weighing the silver-containing particles on the processed surface of the test substrate 200a; supplying ozone gas from the ozone gas supply source 21 to the joints 50 (joints 51-57) and pipes 41-45 until the amount of silver-containing particles falls below a threshold; placing the test substrate 200a in the chamber 10 and processing the test substrate 200a; and weighing the silver-containing particles on the processed surface of the test substrate 200a. This allows the substrate processing to begin after objectively confirming that the amount of silver-containing particles has fallen below a predetermined threshold.

[0053] Furthermore, in this embodiment, as described above, an exhaust pipe section 45b for exhausting ozone gas is provided between the fittings 50 (fittings 51-57) and piping 41-45 and the chamber 10. A valve 45a is provided between the exhaust pipe section 45b and the chamber 10. With the valve 45a closed, ozone gas is supplied from the ozone gas supply source 21 to the fittings 50 (fittings 51-57) and piping 41-45 to discharge silver-containing particles in the fittings 50 (fittings 51-57) and piping 41-45 to the exhaust pipe section 45b. As a result, the silver derived from the silver plating of the fittings 50 (fittings 51-57) and piping 41-45 is oxidized by the ozone gas and discharged from the exhaust pipe section 45b, thereby effectively suppressing the inflow of silver-containing particles into the chamber 10.

[0054] (Second Embodiment) The configuration of the substrate processing apparatus 101 according to the second embodiment of the present invention will be described with reference to Figures 6 and 7. Components similar to those in the first embodiment are denoted by the same reference numerals, and their descriptions are omitted as appropriate. Similarly, descriptions of processing methods similar to those in the first embodiment are also omitted as appropriate.

[0055] In this embodiment, as shown in Figure 6, measuring units 61 to 64 are provided in the exhaust pipe sections 42b, 43b, 44b, and 45b to measure silver-containing particles contained in the gas flowing inside the joints 50 (joints 51 to 57) and pipes 41 to 45. Specifically, a measuring unit 61 is provided in the exhaust pipe section 42b. The measuring unit 61 measures the silver-containing particles contained in the gas discharged from the exhaust pipe section 42b. A measuring unit 62 is provided in the exhaust pipe section 43b. The measuring unit 62 measures the silver-containing particles contained in the gas discharged from the exhaust pipe section 43b. A measuring unit 63 is provided in the exhaust pipe section 44b. The measuring unit 63 measures the silver-containing particles contained in the gas discharged from the exhaust pipe section 44b. A measuring unit 64 is provided in the exhaust pipe section 45b. The metering unit 64 measures the amount of silver-containing particles in the gas discharged from the exhaust pipe section 45b.

[0056] The metering units 61-64 may, for example, be configured to collect particles contained in the discharged gas and measure the amount of collected particles. The metering units 61-64 may be provided separately from each other, or they may be provided in common to measure the gas discharged from the exhaust pipes 42b, 43b, 44b, and 45b together. The metering unit 61 may also be provided downstream of the joints 50 (joints 51-57) and the piping 41-45, and / or in the chamber 10.

[0057] Furthermore, in this embodiment, in order to suppress the accumulation of unintended silver-containing particles in the chamber 10 during the processing of the semiconductor substrate 200, a process is performed to remove silver from the pipes 41-45 and fittings 50 (fittings 51-57) before processing the semiconductor substrate 200. In other words, the silver removal method of the substrate processing apparatus 100 comprises an oxidation step of supplying ozone gas to the pipes 41-45 that supply processing gas to the chamber 10 where the semiconductor substrate 200 to be processed is placed, thereby oxidizing the silver in the pipes 41-45 and fittings 50 (fittings 51-57), and a discharge step of supplying ozone gas or purge gas to the pipes 41-45, thereby discharging the silver oxide oxidized by the ozone gas from the pipes 41-45 and fittings 50 (fittings 51-57) to the outside.

[0058] Furthermore, the semiconductor substrate 200 processing method of this embodiment includes the steps of supplying ozone gas from the ozone gas supply source 21 to the joints 50 (joints 51-57), pipes 41-45 and exhaust pipes 42b, 43b, 44b, and 45b with the valve 45a closed and the metering units 61-64 activated, and stopping the supply of ozone gas from the ozone gas supply source 21 and opening the valve 45a after the amount of silver-containing particles measured by the metering units 61-64 falls below a threshold.

[0059] Furthermore, the semiconductor substrate processing method of this embodiment includes the steps of supplying ozone gas from the ozone gas supply source 21 to the joints 50 (joints 51 to 57) and pipes 41 to 45 with the metering units 61 to 64 in operation, without placing the semiconductor substrate 200 in the chamber 10, and stopping the supply of ozone gas from the ozone gas supply source 21 after the amount of silver-containing particles measured by the metering units 61 to 64 falls below a threshold.

[0060] Next, with reference to Figure 7, the procedure for processing the semiconductor substrate 200 using the substrate processing apparatus will be described.

[0061] In steps S1 to S3 of Figure 7, the same process as in steps S1 to S3 of Figure 5 is performed.

[0062] In step S11, valve 45a is closed. Also, valves 41a, 42a, 421b, 43a, 431b, 44a, 441b, and 451b are opened.

[0063] In step S12, silver-containing particles are oxidized and removed by ozone gas. Specifically, ozone gas is supplied from the ozone gas supply source 21 to the pipes 41-45. As a result, the silver (Ag) present in the pipes 41-45 and the fittings 51-57 is oxidized to silver oxide (Ag2O, Ag2O2, Ag2O3).

[0064] In step S13, oxidized silver-containing particles are discharged from the exhaust pipe sections 42b, 43b, 44b, and 45b, and the amount of discharged particles is measured in the measuring sections 61 to 64.

[0065] In step S14, it is determined whether the amount of silver-containing particles measured in the weighing units 61-64 is below a predetermined threshold. If the amount of particles is above the predetermined threshold, the process returns to step S12 and steps S12-S14 are repeated. If the amount of particles is below the predetermined threshold, the process proceeds to step S15.

[0066] In step S15, the supply of ozone gas from the ozone gas supply source 21 is stopped. Valve 45a is also opened. Valves 41a, 42a, 421b, 43a, 431b, 44a, 441b, and 451b are closed.

[0067] In step S8, the semiconductor substrate 200 is placed in the chamber 10 and processed.

[0068] The other configurations of the second embodiment are the same as those of the first embodiment described above.

[0069] (Effects of the second embodiment) In the second embodiment, the following effects can be obtained.

[0070] In this embodiment, as described above, the semiconductor substrate 200 processing method includes a step of supplying ozone gas from an ozone gas supply source 21 to the joints 50 (joints 51-57) and pipes 41-45 to remove silver-containing particles originating from the silver plating present in the joints 50 (joints 51-57) and pipes 41-45. As a result, the silver originating from the silver plating of the joints 50 (joints 51-57) and pipes 41-45 is oxidized by the ozone gas and can be discharged from the exhaust pipe sections 42b, 43b, 44b, and 45b, thereby effectively suppressing the inflow of silver-containing particles into the chamber 10.

[0071] Furthermore, in this embodiment, as described above, measuring units 61 to 64 are provided in the exhaust pipe sections 42b, 43b, 44b, and 45b to measure silver-containing particles contained in the gas flowing inside the fittings 50 (fittings 51 to 57) and pipes 41 to 45. The process includes supplying ozone gas from the ozone gas supply source 21 to the fittings 50 (fittings 51 to 57), pipes 41 to 45, and exhaust pipe sections 42b, 43b, 44b, and 45b with the measuring units 61 to 64 activated, and stopping the supply of ozone gas from the ozone gas supply source 21 and opening the valve 45a after the amount of silver-containing particles measured by the measuring units 61 to 64 falls below a threshold. This allows the semiconductor substrate 200 to be processed after objective confirmation that the amount of silver-containing particles has fallen below a predetermined threshold.

[0072] Other effects of the second embodiment are the same as those of the first embodiment described above.

[0073] (Third embodiment) Referring to Figure 8, the configuration of the substrate processing apparatus 102 according to the third embodiment of the present invention will be described. Note that components similar to those in the first embodiment are denoted by the same reference numerals, and their descriptions are omitted as appropriate.

[0074] In this embodiment, as shown in Figure 8, a solvent supply source 70 for supplying the solvent, a solvent piping section 71 connected to the solvent supply source 70 for the flow of the solvent, and a mixing section 72 to which the solvent piping section 71 is connected between the fitting 51 and the pipe 41 and the chamber 10 are provided. The solvent supply source 70 supplies a solvent to be mixed with ozone gas supplied from the ozone gas supply source 21. Specifically, the solvent supply source 70 supplies pure water (water (H2O) with a purity of 99.99% or higher) as the solvent. The solvent supply source 70 includes, for example, a pure water generator such as an ion exchange type or an RO membrane type.

[0075] Furthermore, in this embodiment, in the process of processing the semiconductor substrate 200, the ozone gas and solvent are mixed in the mixing unit 72 and supplied to the chamber 10. In other words, the process of processing the semiconductor substrate 200 includes the process of processing the semiconductor substrate 200 using ozonated water. Also, in the process of removing silver-containing particles from the joints 50 (joints 51-57) and pipes 41-45, ozonated water may be supplied instead of ozone gas. For example, depending on the configuration of the substrate processing device 100 downstream from the ozone gas supply source 21, the user may appropriately select whether to use ozone gas or ozonated water.

[0076] The other configurations of the third embodiment are the same as those of the first embodiment described above.

[0077] (Effects of the third embodiment) In the third embodiment, the following effects can be obtained.

[0078] In this embodiment, as described above, the semiconductor substrate 200 processing method includes a step of supplying ozone gas from an ozone gas supply source 21 to the joints 50 (joints 51-57) and pipes 41-45 to remove silver-containing particles originating from silver plating present in the joints 50 (joints 51-57) and pipes 41-45. This allows the silver-containing particles originating from silver plating present in the joints 50 (joints 51-57) and pipes 41-45 to be converted into silver oxide, which has a lower surface energy and lower adhesion than silver. As a result, the silver-containing particles in the joints 50 (joints 51-57) and pipes 41-45 can be converted into silver oxide and discharged outside the substrate processing apparatus 100. This makes it possible to remove silver-containing particles generated in the joints 50 (joints 51-57) and pipes 41-45 using equipment for supplying ozonated water, which is obtained by dissolving ozone gas used for processing the semiconductor substrate 200 in pure water. This makes it possible to remove silver-containing particles generated in the fittings 50 (fittings 51-57) and pipes 41-45 without requiring any special equipment.

[0079] Other effects of the third embodiment are the same as those of the first embodiment described above.

[0080] It should be noted that the embodiments disclosed herein are illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims rather than by the description of the embodiments above, and further includes all modifications (exceptions) within the meaning and scope equivalent to the claims.

[0081] For example, the above embodiment shows an example of an ozone gas supply source that generates ozone by dielectric barrier discharge, but the present invention is not limited to this. In the present invention, the ozone gas supply source that supplies ozone gas may generate ozone by methods other than dielectric barrier discharge. For example, the ozone gas supply source may generate ozone using ultraviolet light, or it may generate ozone by electrolysis of water. Alternatively, the ozone gas supply source may be a gas cylinder filled with ozone gas.

[0082] Furthermore, while the above embodiment shows an example where silver is present in the piping and chamber due to silver plating applied to the pipe fittings, the present invention is not limited to this. In the present invention, silver may be present in the piping and chamber due to a source other than silver plating on the fittings, and this silver may be removed by ozone gas.

[0083] Furthermore, while the above embodiment shows an example of a configuration in which ozone gas is supplied to pipes other than those supplying ozone gas in order to remove silver, the present invention is not limited to this. In the present invention, it is not necessary to supply ozone gas to pipes other than those supplying ozone gas in order to remove silver. In other words, since ozone gas does not flow through pipes other than those supplying ozone gas during the processing of the semiconductor substrate, even if silver is attached to the inside of the pipe, the attached silver will not be oxidized, so silver peeling is unlikely to occur. For this reason, the possibility of silver-containing particles flowing into the chamber from pipes other than those supplying ozone gas is low.

[0084] Furthermore, while the above embodiment shows an example of a configuration in which ozone gas is used to oxidize and discharge silver-containing particles adhering to the inner walls of pipes and fittings, the present invention is not limited thereto. In the present invention, silver-containing particles are oxidized with ozone gas, and the discharge of the oxidized silver-containing particles to the outside of the substrate processing apparatus may be carried out using a gas or fluid other than ozone gas.

[0085] Furthermore, while the above embodiment shows an example of a configuration in which silver is oxidized with ozone gas and then purge gas is supplied to discharge the silver oxide, the present invention is not limited to this. In the present invention, after oxidizing silver with ozone gas, the silver oxide may be discharged to the outside by continuing to supply ozone gas.

[0086] Furthermore, in the above embodiment, the steps for removing silver (oxidation step and discharge step) were shown to be performed after the piping connection work and before the processing of the semiconductor substrate began, but the present invention is not limited to this. In the present invention, the steps for removing silver (oxidation step and discharge step) may be performed in between the processing of the semiconductor substrate.

[0087] Furthermore, in addition to ozone gas, the piping downstream of other processing gas supply sources may be equipped with pumps, filters, sensors, and other equipment necessary for operating the substrate processing equipment. It is even preferable that this equipment be resistant to oxidation and degradation caused by ozone. [Explanation of Symbols]

[0088] 10 Chambers 21 Ozone gas supply sources 22, 23, 24 Processing gas supply section 30 Exhaust system 41, 42, 43, 44, 45 Piping (Piping section) 41a, 42a, 43a, 44a, 421b, 431b, 441b, 451b valves 42b, 43b, 44b, 45b Exhaust pipe section 45a Valve 50, 51, 52, 53, 54, 55, 56, 57 Joints (joint section) 50d threaded section 61, 62, 63, 64 Measuring section 70 Solvent source 71 Solvent piping section 72 Mixing section 100, 101, 102 Substrate processing equipment 200 semiconductor substrates 200a Test Board

Claims

1. A step of preparing a substrate processing apparatus equipped with a chamber for processing semiconductor substrates, The process of preparing an ozone gas supply source to supply ozone gas, The process involves connecting the joint and piping sections, whose threaded portions are silver-plated, while applying frictional force to the threaded portions, thereby connecting the chamber and the ozone gas supply source. A step of supplying ozone gas from the ozone gas supply source to the joint and the piping to remove silver-containing particles originating from the silver plating present in the joint and the piping, A method for processing a semiconductor substrate, comprising the steps of placing the semiconductor substrate in the chamber and processing the semiconductor substrate.

2. Before the process of processing the semiconductor substrate, A step of placing a test substrate in the chamber and processing the test substrate, A step of weighing the silver-containing particles on the treated surface of the test substrate, A method for processing a semiconductor substrate according to claim 1, characterized by repeating the steps of: supplying ozone gas from the ozone gas supply source to the joint and the piping until the amount of silver-containing particles falls below a threshold; placing the test substrate in the chamber and processing the test substrate; and weighing the silver-containing particles on the processed surface of the test substrate.

3. Between the joint and the piping and the chamber, there is an exhaust pipe for exhausting the ozone gas. A valve is provided between the exhaust pipe section and the chamber. The semiconductor substrate processing method according to claim 1, characterized in that, with the valve closed, ozone gas is supplied from the ozone gas supply source to the joint and the piping to discharge the silver-containing particles in the joint and the piping to the exhaust pipe.

4. The exhaust pipe section is provided with a measuring unit for measuring the silver-containing particles contained in the gas flowing inside the joint and piping sections. With the metering unit in operation, the ozone gas is supplied from the ozone gas supply source to the joint, the piping, and the exhaust pipe. A method for processing a semiconductor substrate according to claim 3, comprising the steps of stopping the supply of ozone gas from the ozone gas supply source and opening the valve after the amount of silver-containing particles measured by the measuring unit falls below a threshold.

5. A measuring unit for measuring silver-containing particles contained in the gas flowing inside the joint and the piping is provided downstream of the joint and the piping, and / or in the chamber. A step of supplying the ozone gas from the ozone gas supply source to the joint and the piping section, with the semiconductor substrate not placed in the chamber and the metering unit in operation, A method for processing a semiconductor substrate according to claim 1, comprising the step of stopping the supply of ozone gas from the ozone gas supply source after the amount of silver-containing particles measured by the measuring unit falls below a threshold.

6. The semiconductor substrate processing method according to claim 1, characterized in that, in the step of processing the semiconductor substrate, the ozone gas is supplied from the ozone gas supply source to the chamber.

7. A solvent source that supplies the solvent, A solvent piping section connected to the solvent supply source through which the solvent flows, A mixing section is provided between the joint section and the piping section and the chamber, to which the solvent piping section is connected. The semiconductor substrate processing method according to claim 6, characterized in that, in the step of processing the semiconductor substrate, the ozone gas and the solvent are mixed in the mixing unit and supplied to the chamber.

8. The method for processing a semiconductor substrate according to claim 7, characterized in that the solvent is pure water.

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