Plasma processing apparatus and plasma processing method

Abstract

The present invention provides a technology capable of suppressing the attachment of particles to a substrate. A plasma processing apparatus according to one embodiment of the present disclosure comprises a processing vessel having a bell-shaped body and an opening formed in a side wall, and accommodating a plurality of substrates in multiple stages inside; a plasma partition wall hermetically provided on the outer wall of the processing vessel, covering the opening and defining a plasma generation space; a plasma electrode provided along the plasma partition wall; and a processing gas supply unit provided outside the plasma generation space and supplying a plasma generation gas.

Description

Technology Field

[0001] The present disclosure relates to a plasma treatment apparatus and a plasma treatment method. Background Technology

[0002] In a batch heat treatment apparatus, a technique is known in which a plasma generating part in which plasma is generated is opened to the inside of a processing vessel and provided in a communicating state (see, for example, Patent Document 1). Prior art literature

[0003] Japanese Patent Publication No. 2004-343017 The problem to be solved

[0004] The present disclosure provides a technology capable of suppressing the attachment of particles to a substrate. means of solving the problem

[0005] A plasma processing apparatus according to one embodiment of the present disclosure comprises a processing vessel having a bell-shaped body and an opening formed in a side wall, and accommodating a plurality of substrates in multiple stages inside; a plasma partition wall hermetically provided on the outer wall of the processing vessel, covering the opening and defining a plasma generation space; a plasma electrode provided along the plasma partition wall; and a processing gas supply unit provided outside the plasma generation space and supplying a plasma generation gas. Effects of the invention

[0006] According to the present disclosure, the attachment of particles to a substrate can be suppressed. Brief explanation of the drawing

[0007] FIG. 1 is a schematic diagram illustrating an example of a plasma processing apparatus of an embodiment. Figure 2 is a diagram illustrating the arrangement of gas nozzles. Figure 3 is a diagram illustrating the flow of gas in a plasma processing apparatus of an embodiment. Figure 4 is a drawing illustrating the arrangement of gas nozzles in the first and second examples. FIG. 5 is a diagram illustrating a first example of a gas supply sequence of a plasma treatment method of an embodiment. FIG. 6 is a diagram illustrating a second example of a gas supply sequence of a plasma treatment method of an embodiment. Figure 7 is a drawing illustrating the arrangement of gas nozzles in the third and fourth examples. FIG. 8 is a diagram illustrating a third example of a gas supply sequence of a plasma treatment method of an embodiment. FIG. 9 is a diagram illustrating a fourth example of a gas supply sequence of a plasma treatment method of an embodiment. Figure 10 is a drawing for explaining the arrangement of gas nozzles of a reference example. FIG. 11 is a diagram illustrating an example of a gas supply sequence of a plasma treatment method of a reference example. Figure 12 is a diagram illustrating another example of a gas supply sequence of a plasma treatment method of a reference example. Figure 13 is a diagram illustrating the trend of the number of particles. Figure 14 is a drawing to explain the location and type of gas nozzle. Figure 15 is a diagram illustrating the film thickness and in-plane uniformity of a SiN film. Figure 16 is a diagram illustrating the film thickness and in-plane uniformity of a SiN film. Figure 17 is a diagram illustrating the WER of a SiN film. Specific details for implementing the invention

[0008] Hereinafter, non-limiting exemplary embodiments of the present disclosure will be described with reference to the accompanying drawings. In all of the accompanying drawings, identical or corresponding members or parts are denoted by identical or corresponding reference numerals, and redundant descriptions are omitted.

[0009] [Plasma Processing Device]

[0010] Referring to FIGS. 1 to 3, an example of a plasma processing apparatus of an embodiment will be described. FIG. 1 is a schematic diagram illustrating an example of a plasma processing apparatus of an embodiment. FIG. 2 is a diagram illustrating the arrangement of gas nozzles. FIG. 3 is a diagram illustrating the flow of gas in a plasma processing apparatus of an embodiment.

[0011] A plasma processing device (100) has a processing vessel (1). The processing vessel (1) has a bell-shaped body with a ceiling that is open at the bottom. The entire processing vessel (1) is formed, for example, by quartz. Near the top of the processing vessel (1), a ceiling plate (2) formed by quartz is provided, and the lower region of the ceiling plate (2) is sealed. A metal manifold (3) formed in a tubular shape is connected to the opening at the bottom of the processing vessel (1) via a seal member (4), such as an O-ring.

[0012] The manifold (3) supports the bottom of the processing vessel (1), and a wafer boat (5) is inserted into the processing vessel (1) from below the manifold (3), in which multiple semiconductor wafers (hereinafter referred to as "wafers (W)") are stacked in multiple layers as substrates (e.g., 25 to 150 wafers). In this way, multiple wafers (W) are accommodated approximately horizontally within the processing vessel (1) at intervals along the vertical direction. The wafer boat (5) is formed, for example, by quartz. The wafer boat (5) has three rods (6) (see FIG. 2), and multiple wafers (W) are supported by grooves (not shown) formed in the rods (6).

[0013] The wafer boat (5) is loaded onto a table (8) via a quartz-formed insulated tube (7). The table (8) is supported on a rotating shaft (10) that passes through a metal (stainless steel) cover (9) that opens and closes the opening at the bottom of the manifold (3).

[0014] A magnetic fluid seal (11) is provided in the through-hole of the rotating shaft (10) to hermetically seal the rotating shaft (10) and also support it rotatably. A seal member (12) is provided between the periphery of the cover (9) and the bottom of the manifold (3) to maintain airtightness within the processing container (1).

[0015] The rotating shaft (10) is installed at the tip of an arm (13) supported by a lifting mechanism (not shown), such as a boat elevator, for example, and the wafer boat (5) and the cover (9) are lifted as a single unit and inserted and separated into the processing container (1). Additionally, a table (8) may be fixed to the side of the cover (9) so that the processing of the wafer (W) is performed without rotating the wafer boat (5).

[0016] In addition, the plasma treatment device (100) has a gas supply unit (20) that supplies various gases into a treatment vessel (1).

[0017] The gas supply unit (20) has four gas nozzles (21 to 24). However, the gas supply unit (20) may have another gas nozzle in addition to the four gas nozzles (21 to 24).

[0018] The gas nozzle (21) is formed, for example, by quartz and has an L-shaped form that penetrates the side wall of the manifold (3) inwardly, bends upward, and extends vertically. The vertical portion of the gas nozzle (21) is provided on the side of the plasma generation space (P) rather than the center (C) of the corresponding processing vessel (1) inside the processing vessel (1), for example, outside the plasma generation space (P). However, the vertical portion of the gas nozzle (21) may be provided on the side of the exhaust port (40) rather than the center (C) of the corresponding processing vessel (1) inside the processing vessel (1). The gas nozzle (21) is connected to a supply source of dichlorosilane (DCS) gas. In the vertical portion of the gas nozzle (21), a plurality of gas holes (21a) are formed at intervals along the vertical length corresponding to the wafer support range of the wafer boat (5). The gas hole (21a) is oriented, for example, at the center (C) of the processing vessel (1) and discharges DCS gas in a horizontal direction toward the center (C) of the processing vessel (1). However, the gas hole (21a) may be oriented, for example, toward the inner wall near the processing vessel (1).

[0019] The gas nozzle (22) is formed, for example, by quartz and has an L-shaped form that penetrates inwardly through the side wall of the manifold (3), bends upward, and extends vertically. The vertical portion of the gas nozzle (22) is provided on the side of the plasma generation space (P) rather than the center (C) of the corresponding processing vessel (1) inside the processing vessel (1), for example, outside the plasma generation space (P). However, the vertical portion of the gas nozzle (22) may be provided on the side of the exhaust port (40) rather than the center (C) of the corresponding processing vessel (1) inside the processing vessel (1). The gas nozzle (22) is connected to an ammonia gas supply source and a hydrogen gas supply source. Ammonia gas and hydrogen gas are examples of gases for plasma generation. In the vertical portion of the gas nozzle (22), a plurality of gas holes (22a) are formed at intervals along the vertical length direction corresponding to the wafer support range of the wafer boat (5). The gas hole (22a) is oriented, for example, at the center (C) of the treatment vessel (1) and discharges ammonia gas and hydrogen gas in a horizontal direction toward the center (C) of the treatment vessel (1). However, the gas hole (22a) may be oriented, for example, toward the plasma generation space (P) side or toward the inner wall side near the treatment vessel (1).

[0020] The gas nozzle (23) is formed, for example, by quartz and has an L-shape that is bent upward and vertically extended by penetrating the side wall of the manifold (3) inwardly. The vertical portion of the gas nozzle (23) is provided in the plasma generation space (P). The gas nozzle (23) is connected to a supply source for purge gas. In the vertical portion of the gas nozzle (23), a plurality of gas holes (23a) are formed at intervals along the vertical length direction corresponding to the wafer support range of the wafer boat (5). The gas holes (23a) are oriented, for example, toward the center (C) of the processing vessel (1) and discharge purge gas in a horizontal direction toward the center (C) of the processing vessel (1). Examples of purge gases include argon gas and nitrogen gas.

[0021] The gas nozzle (24) is formed, for example, by quartz and has a straight tube shape that extends horizontally through the side wall of the manifold (3). The tip portion of the gas nozzle (24) is provided outside the plasma generation space (P), for example, inside the processing vessel (1). The gas nozzle (24) is connected to a source of purge gas. The tip portion of the gas nozzle (24) is open, and purge gas is supplied into the processing vessel (1) through the opening. Examples of purge gas include argon gas and nitrogen gas.

[0022] A plasma generating mechanism (30) is formed in a part of the side wall of the processing vessel (1). The plasma generating mechanism (30) generates active species by plasmaizing ammonia gas and hydrogen gas supplied from the gas nozzle (22).

[0023] The plasma generation mechanism (30) has a plasma partition wall (32), a pair of plasma electrodes (33), a power supply line (34), an RF power source (35), and an insulating protective cover (36).

[0024] The plasma partition wall (32) is hermetically welded to the outer wall of the processing vessel (1). The plasma partition wall (32) is formed, for example, by quartz. The plasma partition wall (32) has a concave cross-sectional shape and covers an opening (31) formed in the side wall of the processing vessel (1). The opening (31) is formed to be elongated in the vertical direction so as to cover all wafers (W) supported on the wafer boat (5) in the vertical direction. In the inner space, i.e., the plasma generation space (P), which is defined by the plasma partition wall (32) and communicates with the inside of the processing vessel (1), a gas nozzle (23) for discharging purge gas is disposed. Additionally, a gas nozzle (21) for discharging DCS gas and a gas nozzle (22) for discharging ammonia gas and hydrogen gas are provided at a location close to a wafer (W) along the inner wall of a processing vessel (1) outside the plasma generation space (P).

[0025] A pair of plasma electrodes (33) each have a slender, elongated shape and are arranged facing each other along the vertical direction on the outer surface of both walls of the plasma partition wall (32). A power supply line (34) is connected to the bottom of each plasma electrode (33).

[0026] The power supply line (34) electrically connects each plasma electrode (33) and the RF power source (35). For example, one end of the power supply line (34) is connected to the lower end, which is the side of the short side of each plasma electrode (33), and the other end is connected to the RF power source (35).

[0027] The RF power supply (35) is connected to the bottom of each plasma electrode (33) via a power supply line (34) to supply RF power of, for example, 13.56 MHz to a pair of plasma electrodes (33). By doing so, RF power is applied to the plasma generation space (P) defined by the plasma partition wall (32). Ammonia gas and hydrogen gas discharged into the processing vessel (1) from the gas nozzle (22) (see arrow F1 in FIG. 3) have a portion of them back-diffusing from the processing vessel (1) into the plasma generation space (P) through the opening (31) (see arrows F2 and F3 in FIG. 3). Then, the back-diffusing ammonia gas and hydrogen gas are plasma-ized in the plasma generation space (P), and the active species generated thereby are supplied into the processing vessel (1) through the opening (31) (see arrows F4 and F5 in FIG. 3).

[0028] An insulating protective cover (36) is installed on the outer side of a plasma partition wall (32) to cover the plasma partition wall (32). An inner portion of the insulating protective cover (36) has a refrigerant passage (not shown), and the plasma electrode (33) is cooled by flowing a refrigerant, such as cooled nitrogen gas, through the refrigerant passage. Additionally, a shield (not shown) may be provided between the plasma electrode (33) and the insulating protective cover (36) to cover the plasma electrode (33). The shield is formed by a conductive material, such as metal, for example, and is grounded.

[0029] An exhaust port (40) for vacuum exhausting the inside of the processing vessel (1) is provided in the side wall portion of the processing vessel (1) facing the opening (31). The exhaust port (40) is formed to be long and narrow vertically in correspondence with the wafer boat (5). An exhaust port cover member (41), formed in a U-shape cross section to cover the exhaust port (40), is installed in the portion of the processing vessel (1) corresponding to the exhaust port (40). The exhaust port cover member (41) extends upward along the side wall of the processing vessel (1). An exhaust pipe (42) for exhausting the processing vessel (1) through the exhaust port (40) is connected to the lower portion of the exhaust port cover member (41). An exhaust device (44), including a pressure control valve (43) for controlling the pressure inside the processing vessel (1) and a vacuum pump, is connected to the exhaust pipe (42), and the inside of the processing vessel (1) is exhausted through the exhaust pipe (42) by the exhaust device (44).

[0030] In addition, a tubular heating mechanism (50) is provided to surround the outer circumference of the processing container (1) and to heat the processing container (1) and the wafer (W) inside it.

[0031] Additionally, the plasma processing device (100) has a control unit (60). The control unit (60) controls the operation of each part of the plasma processing device (100), for example. The control unit (60) may be, for example, a computer. Additionally, a computer program that performs the operation of each part of the plasma processing device (100) is stored in a storage medium. The storage medium may be, for example, a flexible disk, a compact disk, a hard disk, a flash memory, a DVD, etc.

[0032] As described above, according to the plasma processing apparatus (100) of the embodiment, a gas nozzle (22) for supplying plasma generating gas (ammonia gas and hydrogen gas) is provided outside the plasma generating space (P). By doing so, direct gas flow from the plasma generating space (P) to the wafer (W) inside the processing vessel (1) can be suppressed during plasma generation. As a result, the inner wall of the plasma partition wall (32) is plasma sputtered, thereby suppressing particles (e.g., peeled SiN film, quartz fragment) generated in the plasma generating space (P) from adhering to the wafer (W).

[0033] In addition, according to the plasma processing device (100) of the embodiment, since the gas nozzle (22) for supplying gas for plasma generation is installed outside the plasma generation space (P), the installation area of ​​the gas nozzle (22) can be wide. By doing so, the nozzle diameter of the gas nozzle (22) can be increased, or multiple gas nozzles (22) can be provided. Therefore, even when the amount of gas supplied is increased, the flow rate of the gas flowing through the gas nozzle (22) can be reduced. As a result, vibration of the gas nozzle (22) that may occur when a large amount of gas flows through the gas nozzle (22) can be reduced, and the generation of particles caused by vibration of the gas nozzle (22) can be suppressed.

[0034] In addition, according to the plasma processing device (100) of the embodiment, since the gas nozzle (22) for supplying the plasma generating gas is provided outside the plasma generating space (P), the deactivation of active species caused by the increase in pressure of the plasma generating space (P) can be suppressed. Therefore, the probability of deactivation of the active gas is reduced, and a reaction promotion effect at the center of the wafer can be expected.

[0035] In addition, according to the plasma processing device (100) of the embodiment, since the gas nozzle (22) for supplying plasma generating gas is provided outside the plasma generating space (P), the installation area of ​​the gas nozzle (22) can be wide. As a result, multiple gas nozzles (22) can be provided. Therefore, multiple types of plasma generating gases can be used to generate plasma by simultaneously supplying multiple types of plasma generating gases into the processing vessel (1) and back-diffusing them into the plasma generating space (P). On the other hand, when the gas nozzle (22) for supplying plasma generating gas is provided in the plasma generating space (P), the installation area of ​​the gas nozzle (22) is narrow, so, for example, only one gas nozzle (22) can be installed.

[0036] [Plasma Treatment Method]

[0037] Referring to FIGS. 4 and FIG. 5, a first example of a plasma treatment method of an embodiment will be described. FIG. 4 is a diagram illustrating the arrangement of gas nozzles of the first and second examples. FIG. 5 is a diagram illustrating a first example of a gas supply sequence of a plasma treatment method of an embodiment, and shows an example of a gas supply sequence for one cycle when forming a SiN film by the Atomic Layer Deposition (ALD) method. Hereinafter, the gas supply sequence shown in FIG. 5 will also be referred to as "Gas Supply Sequence A".

[0038] In the first and second examples, gas nozzles (GN1, GN3, GN5, GN6) are provided inside a processing vessel (1) outside the plasma generation space (P), and a gas nozzle (GN2) is provided in the plasma generation space (P).

[0039] The gas nozzles (GN1, GN2, GN3, GN5) are dispersion nozzles that are installed extending along the vertical direction of the processing vessel (1) and discharge gas approximately horizontally toward the wafer (W) from a plurality of gas holes formed at intervals along the longitudinal direction. The gas nozzle (GN6) is a nozzle that discharges gas to the lower part of the processing vessel (1).

[0040] Gas nozzle (GN1) is connected to a source of DCS gas and supplies DCS gas into the processing vessel (1). Gas nozzle (GN2) is connected to a source of nitrogen (N2) gas and supplies nitrogen gas to the plasma generation space (P). Gas nozzle (GN3) is connected to a source of ammonia (NH3) gas and a source of hydrogen (H2) gas and supplies ammonia gas and hydrogen gas into the processing vessel (1). Gas nozzle (GN5) is connected to a source of nitrogen (N2) gas and supplies nitrogen gas into the processing vessel (1). Gas nozzle (GN6) is connected to a source of nitrogen (N2) gas and constantly supplies nitrogen gas to the lower part of the processing vessel (1). Additionally, gas nozzles (GN1, GN3) are also connected to a source of nitrogen gas (not shown).

[0041] The plasma treatment method illustrated in FIG. 5 is a method for forming a SiN film by repeating a cycle including a process S11 for supplying DCS gas, a purging process S12, a process S13 for supplying ammonia gas, and a purging process S14.

[0042] In process S11, which supplies DCS gas, DCS gas is adsorbed onto a wafer (W). In this embodiment, DCS gas is supplied into a processing vessel (1) from a gas nozzle (GN1), nitrogen gas is supplied to a plasma generation space (P) from a gas nozzle (GN2), and nitrogen gas is supplied into a processing vessel (1) from gas nozzles (GN1, GN3, GN5, GN6). The DCS gas is initially stored in a buffer tank in process S13, which supplies ammonia gas, and is supplied into the processing vessel (1) in a pressurized state in process S11, which supplies DCS gas. However, the DCS gas may be supplied into the processing vessel (1) without being stored in a buffer tank. The supply amount of DCS gas supplied from the gas nozzle (GN1) is, for example, 300 sccm. The flow rates of nitrogen gas supplied from the gas nozzles (GN1, GN2, GN3, GN5, GN6) are, for example, 500 sccm, 500 sccm, 200 sccm, 50 sccm, and 50 sccm, respectively. In addition, in process S11 where DCS gas is supplied, RF power is not applied to the plasma generation space (P).

[0043] The purging process S12 is performed after the process S11 of supplying DCS gas. In the purging process S12, the DCS gas remaining in the plasma generation space (P) and the treatment vessel (1) is removed. In this embodiment, nitrogen gas is supplied to the plasma generation space (P) from the gas nozzle (GN2), and nitrogen gas is supplied into the treatment vessel (1) from the gas nozzles (GN1, GN3, GN5, GN6). By doing so, the DCS gas remaining in the plasma generation space (P) and the treatment vessel (1) is discharged, and the plasma generation space (P) and the treatment vessel (1) become a nitrogen atmosphere. The flow rates of the nitrogen gas supplied from the gas nozzles (GN1, GN2, GN3, GN5, GN6) are, for example, 5000 sccm, 500 sccm, 5000 sccm, 50 sccm, and 50 sccm, respectively. In addition, in the purging process S12, RF power is not applied to the plasma generation space (P).

[0044] The process S13 for supplying ammonia gas is performed after the purging process S12. In the process S13 for supplying ammonia gas, a reaction product of the DCS gas adsorbed on the wafer (W) and the ammonia gas is produced. In this embodiment, ammonia gas is supplied into the processing vessel (1) from the gas nozzle (GN3), nitrogen gas is supplied into the plasma generation space (P) from the gas nozzle (GN2), and nitrogen gas is supplied into the processing vessel (1) from the gas nozzles (GN1, GN3, GN5, GN6). Additionally, RF power is applied to the plasma generation space (P) by turning on the RF power source (35). In the process S13 for supplying ammonia gas, a portion of the ammonia gas supplied into the processing vessel (1) from the gas nozzle (GN3) is back-diffused from the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing ammonia gas is plasmafied in the plasma generation space (P), and the active species generated thereby is supplied into the treatment vessel (1) and reacts with the DCS gas to produce a reaction product. The flow rate of the ammonia gas supplied from the gas nozzle (GN3) is, for example, 5000 sccm. The flow rate of the nitrogen gas supplied from the gas nozzle (GN2) is preferably smaller than the flow rate of the nitrogen gas supplied from the gas nozzle (GN2) in the process S11 of supplying the DCS gas, for example, 50 sccm. By making the flow rate of the nitrogen gas supplied from the gas nozzle (GN2) smaller in this way, the ammonia gas supplied from the gas nozzle (GN3) becomes easier to back-diffuse from the treatment vessel (1) into the plasma generation space (P). In addition, the flow rates of nitrogen gas supplied from the gas nozzles (GN1, GN3, GN5, GN6) are, for example, 1000 sccm, 500 sccm, 50 sccm, and 50 sccm, respectively.

[0045] The purging process S14 is performed after the process S13 of supplying ammonia gas. In the purging process S14, residual ammonia gas in the plasma generation space (P) and the treatment vessel (1) is removed. In this embodiment, nitrogen gas is supplied to the plasma generation space (P) from the gas nozzle (GN2), and nitrogen gas is supplied into the treatment vessel (1) from the gas nozzles (GN1, GN3, GN5, GN6). By doing so, residual ammonia gas in the plasma generation space (P) and the treatment vessel (1) is discharged, and the plasma generation space (P) and the treatment vessel (1) become a nitrogen atmosphere. The flow rates of the nitrogen gas supplied from the gas nozzles (GN1, GN2, GN3, GN5, GN6) are, for example, 500 sccm, 500 sccm, 200 sccm, 50 sccm, and 50 sccm, respectively. In addition, in the purging process S14, RF power is not applied to the plasma generation space (P).

[0046] A SiN film can be formed on a wafer (W) by performing the cycle including the above processes S11 to S14 multiple times.

[0047] As described above, according to the gas supply sequence A, in process S13 for supplying ammonia gas, ammonia gas is supplied from a gas nozzle (GN3) provided inside a processing vessel (1) outside the plasma generation space (P), and RF power is applied to the plasma generation space (P). As a result, a portion of the ammonia gas supplied from the gas nozzle (GN3) into the processing vessel (1) is back-diffusing from inside the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing ammonia gas is plasma-ized in the plasma generation space (P), and the active species generated thereby is supplied into the processing vessel (1) and reacts with the DCS gas to produce a reaction product. Therefore, the direct flow of gas from the plasma generation space (P) to the wafer (W) inside the processing vessel (1) can be suppressed. As a result, the inner wall of the plasma partition wall (32) is plasma sputtered, thereby preventing particles generated in the plasma generation space (P) from adhering to the wafer (W).

[0048] Additionally, according to gas supply sequence A, nitrogen gas is supplied from a gas nozzle (GN2) provided in the plasma generation space (P) during at least the DCS gas supply process S11, the purging process S12, and the purging process S14. By doing so, the amount of film formed on the inner wall of the plasma partition wall (32) is reduced, thereby suppressing the occurrence of film peeling. As a result, the amount of particles generated in the plasma generation space (P) can be reduced.

[0049] With reference to FIGS. 4 and FIG. 6, a second example of a plasma treatment method of an embodiment will be described. FIG. 6 is a diagram showing a second example of a gas supply sequence of a plasma treatment method of an embodiment, and shows an example of a gas supply sequence for one cycle when forming a SiN film by the ALD method. Hereinafter, the gas supply sequence shown in FIG. 6 will also be referred to as "gas supply sequence B".

[0050] The plasma treatment method illustrated in FIG. 6 is a method for forming a SiN film by repeating a cycle including a process S21 for supplying DCS gas, a purging process S22, a process S25 for supplying hydrogen gas, a process S23 for supplying ammonia gas, and a purging process S24.

[0051] The process S21 for supplying DCS gas, the process S22 for purging, the process S23 for supplying ammonia gas, and the process S24 for purging are identical to the processes S11 to S14 in the first example.

[0052] The process S25 for supplying hydrogen gas is performed after the purging process S22 and before the process S23 for supplying ammonia gas. In the process S25 for supplying hydrogen gas, hydrogen plasma is generated to treat the wafer (W) contained within the processing vessel (1) with hydrogen plasma. In this embodiment, hydrogen gas is supplied into the processing vessel (1) from the gas nozzle (GN3), nitrogen gas is supplied to the plasma generation space (P) from the gas nozzle (GN2), and nitrogen gas is supplied into the processing vessel (1) from the gas nozzles (GN1, GN3, GN5, GN6). Additionally, RF power is applied to the plasma generation space (P) by turning on the RF power source (35). In the process S25 for supplying hydrogen gas, a portion of the hydrogen gas supplied into the processing vessel (1) from the gas nozzle (GN3) is back-diffused from within the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing hydrogen gas is plasmafied in the plasma generation space (P), and the active species generated thereby is supplied into the treatment vessel (1). The flow rate of the hydrogen gas supplied from the gas nozzle (GN3) is, for example, 2000 sccm. The flow rate of the nitrogen gas supplied from the gas nozzle (GN2) is preferably smaller than the flow rate of the nitrogen gas supplied from the gas nozzle (GN2) in process S21, which supplies the DCS gas, and is, for example, 50 sccm. By reducing the flow rate of the nitrogen gas supplied from the gas nozzle (GN2) in this way, the hydrogen gas supplied from the gas nozzle (GN3) becomes easier to back-diffuse from within the treatment vessel (1) into the plasma generation space (P). In addition, the flow rates of the nitrogen gas supplied from the gas nozzles (GN1, GN3, GN5, GN6) are, for example, 1000 sccm, 500 sccm, 50 sccm, and 50 sccm, respectively.

[0053] A SiN film can be formed on a wafer (W) by performing the above-mentioned process S21 to S25 cycles multiple times.

[0054] As described above, according to the gas supply sequence B, in process S23 for supplying ammonia gas, ammonia gas is supplied from a gas nozzle (GN3) provided inside a processing vessel (1) outside the plasma generation space (P), and RF power is applied to the plasma generation space (P). As a result, a portion of the ammonia gas supplied from the gas nozzle (GN3) into the processing vessel (1) is back-diffusing from inside the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing ammonia gas is plasma-ized in the plasma generation space (P), and the active species generated thereby is supplied into the processing vessel (1) and reacts with the DCS gas to produce a reaction product. Therefore, the direct flow of gas from the plasma generation space (P) to the wafer (W) inside the processing vessel (1) can be suppressed. As a result, the inner wall of the plasma partition wall (32) is plasma sputtered, thereby preventing particles generated in the plasma generation space (P) from adhering to the wafer (W).

[0055] Additionally, according to the gas supply sequence B, at least in the process S21 for supplying DCS gas, the process S22 for purging, and the process S24 for purging, nitrogen gas is supplied from the gas nozzle (GN2) provided in the plasma generation space (P). By doing so, the amount of film formed on the inner wall of the plasma partition wall (32) is reduced, thereby suppressing the occurrence of film peeling. As a result, the amount of particles generated in the plasma generation space (P) can be reduced.

[0056] Additionally, according to the gas supply sequence B, in the process S25 for supplying hydrogen gas, hydrogen gas is supplied from a gas nozzle (GN3) provided inside the processing vessel (1), which is outside the plasma generation space (P), and RF power is applied to the plasma generation space (P). As a result, a portion of the hydrogen gas supplied from the gas nozzle (GN3) into the processing vessel (1) is back-diffusing from inside the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing hydrogen gas is plasma-ized in the plasma generation space (P), and the active species generated thereby is supplied into the processing vessel (1). Therefore, the direct flow of gas from the plasma generation space (P) to the wafer (W) inside the processing vessel (1) can be suppressed. As a result, the inner wall of the plasma partition wall (32) is plasma-sputtered, thereby suppressing the attachment of particles generated in the plasma generation space (P) onto the wafer (W).

[0057] Referring to FIGS. 7 and 8, a third example of a plasma treatment method of the embodiment will be described. FIG. 7 is a diagram illustrating the arrangement of gas nozzles in the third and fourth examples. FIG. 8 is a diagram showing a third example of a gas supply sequence of a plasma treatment method of the embodiment, and shows an example of a gas supply sequence for one cycle when forming a SiN film by the ALD method. Hereinafter, the gas supply sequence shown in FIG. 8 will also be referred to as "gas supply sequence C".

[0058] In the third and fourth examples, gas nozzles (GN1, GN3, GN5, GN6) are provided inside the processing vessel (1) which is outside the plasma generation space (P), but gas nozzles are not provided in the plasma generation space (P).

[0059] The gas nozzles (GN1, GN3, GN5) are dispersion nozzles that are installed extending along the vertical direction of the processing vessel (1) and discharge gas approximately horizontally toward the wafer (W) from a plurality of gas holes formed at intervals along the longitudinal direction. The gas nozzle (GN6) is a nozzle that discharges gas to the lower part of the processing vessel (1). The gas nozzles (GN1, GN3, GN5, GN6) are the same as those in FIG. 4.

[0060] The plasma treatment method illustrated in FIG. 8 is a method for forming a SiN film by repeating a cycle including a process S31 for supplying DCS gas, a purging process S32, a process S33 for supplying ammonia gas, and a purging process S34.

[0061] Gas supply sequence C differs from gas supply sequence A in that it does not supply nitrogen gas to the plasma generation space (P) in processes S31 to S34. In addition, it is identical to gas supply sequence A in other respects.

[0062] According to the gas supply sequence C, in process S33 for supplying ammonia gas, ammonia gas is supplied from a gas nozzle (GN3) provided inside a processing vessel (1) outside the plasma generation space (P), and RF power is applied to the plasma generation space (P). As a result, a portion of the ammonia gas supplied from the gas nozzle (GN3) into the processing vessel (1) is back-diffusing from inside the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing ammonia gas is plasma-ized in the plasma generation space (P), and the active species generated thereby is supplied into the processing vessel (1) and reacts with the DCS gas to produce a reaction product. Therefore, the direct flow of gas from the plasma generation space (P) to the wafer (W) inside the processing vessel (1) can be suppressed. As a result, the inner wall of the plasma partition wall (32) is plasma sputtered, thereby preventing particles generated in the plasma generation space (P) from adhering to the wafer (W).

[0063] With reference to FIGS. 7 and FIG. 9, a fourth example of a plasma treatment method of an embodiment will be described. FIG. 9 is a diagram showing a fourth example of a gas supply sequence of a plasma treatment method of an embodiment, and shows an example of a gas supply sequence for one cycle when forming a SiN film by the ALD method. Hereinafter, the gas supply sequence shown in FIG. 9 will also be referred to as "gas supply sequence D".

[0064] The plasma treatment method illustrated in FIG. 9 is a method for forming a SiN film by repeating a cycle including a process S41 for supplying DCS gas, a purging process S42, a process S45 for supplying hydrogen gas, a process S43 for supplying ammonia gas, and a purging process S44.

[0065] Gas supply sequence D differs from gas supply sequence B in that it does not supply nitrogen gas to the plasma generation space (P) in processes S41 to S45. In addition, it is identical to gas supply sequence B in other respects.

[0066] According to the gas supply sequence D, in process S43 for supplying ammonia gas, ammonia gas is supplied from a gas nozzle (GN3) provided inside a processing vessel (1) outside the plasma generation space (P), and RF power is applied to the plasma generation space (P). As a result, a portion of the ammonia gas supplied from the gas nozzle (GN3) into the processing vessel (1) is back-diffusing from inside the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing ammonia gas is plasma-ized in the plasma generation space (P), and the active species generated thereby is supplied into the processing vessel (1) and reacts with the DCS gas to produce a reaction product. Therefore, the direct flow of gas from the plasma generation space (P) to the wafer (W) inside the processing vessel (1) can be suppressed. As a result, the inner wall of the plasma partition wall (32) is plasma sputtered, thereby preventing particles generated in the plasma generation space (P) from adhering to the wafer (W).

[0067] Additionally, according to the gas supply sequence D, in process S45 where hydrogen gas is supplied, hydrogen gas is supplied from a gas nozzle (GN3) provided inside a processing vessel (1) outside the plasma generation space (P), and RF power is applied to the plasma generation space (P). As a result, a portion of the hydrogen gas supplied from the gas nozzle (GN3) into the processing vessel (1) is back-diffusing from inside the processing vessel (1) into the plasma generation space (P). Then, the back-diffusing hydrogen gas is plasma-ized in the plasma generation space (P), and the active species generated thereby is supplied into the processing vessel (1). Therefore, the direct flow of gas from the plasma generation space (P) to the wafer (W) inside the processing vessel (1) can be suppressed. As a result, the inner wall of the plasma partition wall (32) is plasma-sputtered, thereby suppressing the attachment of particles generated in the plasma generation space (P) onto the wafer (W).

[0068] Referring to FIG. 10 and FIG. 11, an example of a plasma processing method of a reference example will be described. FIG. 10 is a drawing for explaining the arrangement of gas nozzles of a reference example. FIG. 11 is a drawing illustrating an example of a plasma processing method of a reference example and shows an example of a gas supply sequence for one cycle when depositing a SiN film by the ALD method. Hereinafter, the gas supply sequence shown in FIG. 11 will also be referred to as "gas supply sequence Y".

[0069] In the reference example, gas nozzles (GN1, GN4, GN5, GN6) are provided inside a processing vessel (1) outside the plasma generation space (P), and a gas nozzle (GN2) is provided in the plasma generation space (P).

[0070] The gas nozzles (GN1, GN2, GN4, GN5) are dispersion nozzles that are installed extending along the vertical direction of the processing vessel (1) and discharge gas approximately horizontally toward the wafer (W) from a plurality of gas holes formed at intervals along the longitudinal direction. The gas nozzle (GN6) is a nozzle that discharges gas to the lower part of the processing vessel (1).

[0071] Gas nozzle (GN1) is connected to a source of DCS gas and supplies DCS gas into the processing vessel (1). Gas nozzle (GN2) is connected to a source of hydrogen (H2) gas, a source of ammonia (NH3) gas, and a source of nitrogen (N2) gas and supplies hydrogen gas, ammonia gas, and nitrogen gas to the plasma generation space (P). Gas nozzle (GN4) is connected to a source of nitrogen (N2) gas and supplies nitrogen gas into the processing vessel (1). Gas nozzle (GN5) is connected to a source of nitrogen (N2) gas and supplies nitrogen gas into the processing vessel (1). Gas nozzle (GN6) is connected to a source of nitrogen (N2) gas and constantly supplies nitrogen gas to the lower part of the processing vessel (1). Additionally, gas nozzle (GN1) is also connected to a source of nitrogen gas (not shown).

[0072] The plasma treatment method illustrated in FIG. 11 is a method for forming a SiN film by repeating a cycle including a process S81 for supplying DCS gas, a purging process S82, a process S83 for supplying ammonia gas, and a purging process S84.

[0073] Gas supply sequence Y differs from gas supply sequence A in that, in process S83 for supplying ammonia gas, ammonia gas is supplied to the plasma generation space (P) from a gas nozzle (GN2) provided in the plasma generation space (P). In addition, it is identical to gas supply sequence A in other respects.

[0074] In the gas supply sequence Y, ammonia gas is flowed from the plasma generation space (P) to excite the gas. As a result, particles from the plasma sputter are transported to the wafer (W) by riding the gas flow from the plasma generation space (P) toward the processing vessel (1). Consequently, the particles are easily attached to the wafer (W).

[0075] With reference to FIG. 10 and FIG. 12, another example of the plasma treatment method of the reference example will be described. FIG. 12 is a drawing illustrating another example of the plasma treatment method of the reference example and shows an example of a gas supply sequence for one cycle when forming a SiN film by the ALD method. Hereinafter, the gas supply sequence shown in FIG. 12 will also be referred to as "gas supply sequence Z".

[0076] The plasma treatment method illustrated in FIG. 12 is a method for forming a SiN film by repeating a cycle including a process S91 for supplying DCS gas, a purging process S92, a process S95 for supplying hydrogen gas, a process S93 for supplying ammonia gas, and a purging process S94.

[0077] Gas supply sequence Z differs from gas supply sequence B in that, in process S93 for supplying ammonia gas, ammonia gas is supplied to the plasma generation space (P) from a gas nozzle (GN2) provided in the plasma generation space (P). Additionally, gas supply sequence Z differs from gas supply sequence B in that, in process S95 for supplying hydrogen gas, hydrogen gas is supplied to the plasma generation space (P) from a gas nozzle (GN2) provided in the plasma generation space (P). Furthermore, regarding other aspects, it is identical to gas supply sequence B.

[0078] In the gas supply sequence Z, ammonia gas and hydrogen gas are flowed from the plasma generation space (P) to excite the gas. As a result, particles from the plasma sputter are transported to the wafer (W) by riding the gas flow from the plasma generation space (P) toward the processing vessel (1). Consequently, the particles are easily attached to the wafer (W).

[0079] [Evaluation of Particles]

[0080] In order to verify the effect of the plasma treatment device (100) of the embodiment, the difference in the supply position of ammonia gas when forming a SiN film on a wafer (W) by the ALD method using DCS gas and ammonia gas was evaluated on the effect on the number of particles attached to the wafer (W).

[0081] In the evaluation of particles, a series of operations were repeated in which a wafer (W) was introduced into a processing vessel (1), a film deposition process was performed to deposit a SiN film on the introduced wafer (W), the wafer (W) after processing was removed, and the number of particles attached to the wafer (W) after processing was measured. In the film deposition process, gas supply sequence A and gas supply sequence Y were used.

[0082] FIG. 13 is a diagram illustrating the trend of the number of particles. FIG. 13 (a), FIG. 13 (b), and FIG. 13 (c) respectively show the results of a wafer (W) mounted in the upper (TOP) region, central (CTR) region, and lower (BTM) region in the vertical direction of the wafer boat (5). In FIG. 13 (a) to FIG. 13 (c), the horizontal axis represents the thickness [μm] of the deposit deposited on the inner wall of the processing vessel (1), and the vertical axis represents the number [pcs] of particles with a particle size of 1 μm or more attached to the wafer (W). In addition, in FIG. 13 (a) to FIG. 13 (c), the solid line represents the result when gas supply sequence A is used, in other words, when ammonia gas is supplied from a gas nozzle provided outside the plasma generation space (P). The dashed line represents the result when using the gas supply sequence Y, in other words, when ammonia gas is supplied from a gas nozzle provided in the plasma generation space (P).

[0083] As illustrated in FIG. 13 (a), in the TOP region, when ammonia gas is supplied from a gas nozzle provided in the plasma generation space (P), if the thickness of the deposit on the inner wall of the processing vessel (1) exceeds 1.5 μm, the number of particles attached to the wafer (W) increases. On the other hand, when ammonia gas is supplied from a gas nozzle provided outside the plasma generation space (P), even if the thickness of the deposit on the inner wall of the processing vessel (1) reaches 2.5 μm, no increase in the number of particles attached to the wafer (W) is observed.

[0084] As illustrated in FIG. 13(b), in the CTR region, when ammonia gas is supplied from a gas nozzle provided in the plasma generation space (P), if the thickness of the deposit on the inner wall of the processing vessel (1) exceeds 0.25 μm, the number of particles attached to the wafer (W) increases. On the other hand, when ammonia gas is supplied from a gas nozzle provided outside the plasma generation space (P), even if the thickness of the deposit on the inner wall of the processing vessel (1) reaches 2.5 μm, no increase in the number of particles attached to the wafer (W) is observed.

[0085] As shown in Fig. 13 (c), in the BTM region, there is no difference in the number of particles when ammonia gas is supplied from a gas nozzle provided outside the plasma generation space (P) and when ammonia gas is supplied from a gas nozzle provided inside the plasma generation space (P).

[0086] From these results, it can be said that by supplying ammonia gas from a gas nozzle provided outside the plasma generation space (P), the adhesion of particles to the wafer (W) can be suppressed more effectively than by supplying ammonia gas from a gas nozzle provided inside the plasma generation space (P).

[0087] [Evaluation of Film Thickness]

[0088] In order to confirm the effect on the film characteristics of the SiN film formed using the plasma treatment device (100) of the embodiment, the effect on the film thickness of the difference in the supply position of ammonia gas when forming a SiN film on a wafer (W) by the ALD method using DCS gas and ammonia gas was evaluated.

[0089] In evaluating the film thickness, a wafer (W) was introduced into a processing vessel (1), a film deposition process was performed to deposit a SiN film on the introduced wafer (W), the wafer (W) after processing was removed, and the film thickness of the SiN film was measured at multiple locations within the plane of the wafer (W) after processing. Gas supply sequence A and gas supply sequence Y were used in the film deposition process.

[0090] Specifically, the silicon-containing gas was supplied from a gas nozzle provided outside the plasma generation space (P). The ammonia gas was supplied from the gas nozzles shown in FIG. 14 (a) to FIG. 14 (c). The gas nozzle (GN-a) shown in FIG. 14 (a) is a dispersion nozzle that extends along the vertical direction of the processing vessel (1) inside the plasma generation space (P) and discharges gas approximately horizontally toward the wafer (W) from a plurality of gas holes formed at intervals along the longitudinal direction. The gas nozzle (GN-b) shown in FIG. 14 (b) is a dispersion nozzle that extends along the vertical direction of the processing vessel (1) outside the plasma generation space (P) and discharges gas approximately horizontally toward the wafer (W) from a plurality of gas holes formed at intervals along the longitudinal direction. The gas nozzle (GN-c) shown in FIG. 14 (c) is an L-shaped nozzle provided outside the plasma generation space (P) and discharges gas from the bottom to the top of the processing vessel (1). FIG. 14 is also a drawing for explaining the location and type of the gas nozzle.

[0091] FIG. 15 is a diagram illustrating the film thickness and in-plane uniformity of a SiN film, showing the film thickness of the SiN film and the in-plane uniformity of the SiN film thickness in the TOP region, CTR region, and BTM region. The left axis of FIG. 15 represents the film thickness (Thickness) [Å], and the right axis represents the in-plane uniformity (WinW Uniformity) [±%]. In FIG. 15, the black triangle mark with a solid line, the black circle mark with a solid line, and the black diamond mark with a solid line represent the film thickness of the SiN film when using gas nozzles (GN-a), gas nozzle (GN-b), and gas nozzle (GN-c), respectively. In addition, in FIG. 15, the black triangle mark without a solid line, the black circle mark without a solid line, and the black diamond mark without a solid line represent the in-plane uniformity of the film thickness of the SiN film when using the gas nozzle (GN-a), the gas nozzle (GN-b), and the gas nozzle (GN-c), respectively.

[0092] As shown in FIG. 15, regarding the in-plane uniformity of the SiN film thickness, when using gas nozzles (GN-b, GN-c) provided outside the plasma generation space (P), approximately the same result was obtained as when using gas nozzle (GN-a) provided inside the plasma generation space (P). Also, regarding the SiN film thickness, when using dispersion nozzle (GN-b) provided outside the plasma generation space (P), approximately the same result was obtained as when using dispersion nozzle (GN-a) provided inside the plasma generation space (P). Additionally, regarding the SiN film thickness, when using L-shaped nozzle (GN-c) provided outside the plasma generation space (P), it became slightly thinner in the CTR region and TOP region. From these results, it can be said that using a dispersion nozzle (GN-b) is preferable in that, when a gas nozzle is provided to supply ammonia gas outside the plasma generation space (P), the effect on the film thickness of the SiN film and the in-plane uniformity of the SiN film thickness is small.

[0093] Next, regarding the membrane treatment, the case where gas supply sequence B and gas supply sequence Z are used will be explained.

[0094] Specifically, the silicon-containing gas was supplied from a gas nozzle provided outside the plasma generation space (P). The ammonia gas and hydrogen gas were supplied from the gas nozzle (GN-a) shown in FIG. 14 (a) and the gas nozzle (GN-b) shown in FIG. 14 (b).

[0095] FIG. 16 is a diagram illustrating the film thickness and in-plane uniformity of a SiN film, showing the film thickness of the SiN film and the in-plane uniformity of the SiN film thickness in the TOP region, CTR region, and BTM region. The left axis of FIG. 16 represents the film thickness [Å], and the right axis represents the in-plane uniformity [±%]. In FIG. 16, the white triangles marked with solid lines and the white circles marked with solid lines represent the film thickness of the SiN film when using the gas nozzle (GN-a) and the gas nozzle (GN-b), respectively. Additionally, in FIG. 16, the white triangles marked without solid lines and the white circles marked without solid lines represent the in-plane uniformity of the SiN film thickness when using the gas nozzle (GN-a) and the gas nozzle (GN-b), respectively.

[0096] As shown in FIG. 16, regarding the film thickness of the SiN film and the in-plane uniformity of the SiN film thickness, when a gas nozzle (GN-b) provided outside the plasma generation space (P) is used, approximately the same result is obtained as when a gas nozzle (GN-a) provided inside the plasma generation space (P) is used. From this result, it is thought that even when a gas nozzle supplying hydrogen gas and ammonia gas is provided outside the plasma generation space (P), the effect on the film thickness of the SiN film and the in-plane uniformity of the SiN film thickness is small.

[0097] [Evaluation of Membrane Quality]

[0098] In order to confirm the effect on the film characteristics of a SiN film formed using a plasma treatment device (100) of the embodiment, the effect on the film quality of the difference in the supply position of ammonia gas when forming a SiN film on a wafer (W) by the ALD method using DCS gas and ammonia gas was evaluated.

[0099] In evaluating the film quality, a wafer (W) was introduced into a processing vessel (1), and a film deposition process was performed to deposit a SiN film on the introduced wafer (W). After the process, the wafer (W) was removed, and the etching resistance of the SiN film deposited on the wafer (W) after the process was evaluated. In evaluating the etching resistance, the SiN film was wet-etched with 0.25% DHF (diluted hydrofluoric acid), and the etching amount was measured to calculate the etching rate (WER: Wet Etch Rate). The lower the WER, the higher the etching resistance and the better the film quality.

[0100] Specifically, the silicon-containing gas was supplied from a gas nozzle provided outside the plasma generation space (P). The ammonia gas and hydrogen gas were supplied from the gas nozzle (GN-a) shown in FIG. 14 (a) and the gas nozzle (GN-b) shown in FIG. 14 (b).

[0101] FIG. 17 is a diagram illustrating the WER of a SiN film, showing the WER of the SiN film in the TOP region, CTR region, and BTM region. The vertical axis of FIG. 17 represents WER [Å / min]. In FIG. 17, the black triangle with a solid line indicates the WER of the SiN film deposited by gas supply sequence Y using a gas nozzle (GN-a), and the black circle with a solid line indicates the WER of the SiN film deposited by gas supply sequence A using a gas nozzle (GN-b). Additionally, the white triangle with a solid line indicates the WER of the SiN film deposited by gas supply sequence Z using a gas nozzle (GN-a), and the white circle with a solid line indicates the WER of the SiN film deposited by gas supply sequence B using a gas nozzle (GN-b).

[0102] As shown in Fig. 17, there was almost no difference in WER between the SiN film deposited by gas supply sequence A and the SiN film deposited by gas supply sequence Y. In addition, the WER of the SiN film deposited by gas supply sequence B was slightly larger than the WER of the SiN film deposited by gas supply sequence Z in the CTR region and BTM region.

[0103] In addition, in the above embodiment, the gas nozzle (22) is an example of a processing gas supply unit, and the gas nozzle (23) is an example of a purge gas supply unit. Also, the DCS gas is an example of a raw material gas, the ammonia gas is an example of a reaction gas, and the hydrogen gas is an example of a reforming gas.

[0104] The embodiments disclosed herein are illustrative in all respects and should not be considered restrictive. The above embodiments may be omitted, substituted, or modified in various forms without departing from the scope and spirit of the attached claims.

[0105] In the above embodiment, the plasma processing device (100) has a pair of opposing plasma electrodes (33) as an example, that is, the plasma processing device (100) has a capacitively coupled plasma electrode (33), but the present disclosure is not limited thereto. For example, the plasma processing device (100) may have an inductively coupled plasma electrode provided along its length direction on a plasma partition wall (32).

[0106] In the above embodiment, the case where the processing vessel (1) has a single-tube structure was described as an example, but the present disclosure is not limited thereto. For example, the processing vessel (1) may have a double-tube structure including an inner tube and an outer tube.

[0107] In the above embodiments, the case of forming a film by the ALD method was described as an example, but the present disclosure is not limited thereto. For example, it can also be applied to cases where a film is formed by the Chemical Vapor Deposition (CVD) method.

[0108] In the above embodiments, ammonia gas and hydrogen gas were described as examples of gases for generating plasma, but the present disclosure is not limited thereto. For example, the gases for generating plasma may be nitrogen gas, argon gas, helium gas, or oxygen gas.

Claims

Claim 1 A plasma processing device comprising: a processing vessel having a bell-shaped body and an opening formed in a side wall, accommodating a plurality of substrates in multiple stages inside; a plasma partition wall hermetically provided on the outer wall of the processing vessel, covering the opening and defining a plasma generation space; a plasma electrode provided along the plasma partition wall; and a processing gas supply unit provided outside the plasma generation space and inside the processing vessel, supplying a plasma generation gas, wherein the plasma is generated by reverse diffusion of the plasma generation gas from inside the processing vessel into the plasma generation space. Claim 2 A plasma treatment device according to claim 1, wherein the opening is formed to be elongated in the height direction of the treatment vessel. Claim 3 A plasma processing apparatus according to claim 1 or 2, wherein the opening has a length capable of covering all of the plurality of substrates in the height direction. Claim 4 A plasma treatment apparatus according to claim 1 or 2, wherein the treatment gas supply unit is installed extending along the height direction of the treatment vessel and includes a dispersion nozzle having a plurality of gas holes formed at intervals in the longitudinal direction. Claim 5 A plasma processing apparatus according to claim 1 or 2, comprising a purge gas supply unit provided in the plasma generation space for supplying purge gas. Claim 6 In claim 5, the purge gas supply unit is installed extending along the height direction of the processing vessel and includes a dispersion nozzle having a plurality of gas holes formed at intervals in the longitudinal direction, a plasma processing device. Claim 7 A plasma processing apparatus according to claim 1 or 2, wherein the plasma electrode comprises a pair of electrodes disposed opposite the outer surfaces of both sides of the plasma partition wall. Claim 8 A plasma processing apparatus according to claim 1 or 2, wherein the plasma electrode comprises an inductively coupled electrode provided along the longitudinal direction of the plasma partition wall. Claim 9 A plasma processing method comprising: a process of accommodating a plurality of substrates in multiple stages inside a processing vessel having a bell-shaped body and an opening formed in a side wall; and a process of discharging a plasma generating gas into the processing vessel, which is outside a plasma generating space defined by a plasma partition wall that covers the opening and is hermetically provided on the side wall of the processing vessel, and back-diffusing at least a portion of the plasma generating gas discharged into the processing vessel into the plasma generating space, while supplying RF power to a plasma electrode provided along the plasma partition wall to plasmaize the plasma generating gas. Claim 10 A plasma treatment method according to claim 9, comprising a process of supplying purge gas to the plasma generation space. Claim 11 A plasma treatment method according to claim 10, comprising a process of supplying a raw material gas into the treatment vessel, wherein the plasma generating gas is a reaction gas that reacts with the raw material gas to produce a reaction product, and repeating a cycle comprising the process of supplying the raw material gas, the process of plasmaizing the plasma generating gas, and the process of supplying the purge gas. Claim 12 A plasma treatment method according to claim 11, comprising a process of plasmaizing the reforming gas by supplying the reforming gas into the treatment vessel outside the plasma generation space and supplying RF power to the plasma electrode, and repeating a cycle comprising a process of supplying the raw material gas, a process of plasmaizing the plasma generation gas, a process of supplying the purge gas, and a process of plasmaizing the reforming gas. Claim 13 A plasma treatment method according to claim 12, wherein the raw material gas is DCS gas, the reaction gas is ammonia gas, and the reforming gas is hydrogen gas.

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