Substrate processing apparatus, injection apparatus, substrate processing method, method of manufacturing semiconductor device, and recording medium

Abstract

To provide a substrate processing apparatus, an injection device, a substrate processing method, a method of manufacturing a semiconductor device, and a program, which enlarge a flow passage area of a processing gas.SOLUTION: The substrate processing apparatus includes an injection device which is provided on the side of a substrate in a processing container (reaction chamber 5) for housing the substrate 9 inside, extends along a direction perpendicular to the substrate, and injects a gas to the substrate, and the injection device has a cylindrical first nozzle 22 and a second nozzle 23. Each of the first nozzle and the second nozzle has a flat surface formed on a side facing the substrate, two surfaces respectively connected to both sides of the flat surface, a plurality of first jet holes 91 disposed on the flat surface along a direction parallel to the substrate and configured to jet gas in substantially the same direction, and a second jet hole disposed on at least one of the two surfaces and configured to jet gas in a direction inclined with respect to the same direction.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a substrate processing apparatus, a spraying apparatus, a substrate processing method, a method for manufacturing a semiconductor device, and a program. [Background technology]

[0002] In a semiconductor device manufacturing method, a vertical substrate processing apparatus is known as an example of an apparatus for forming an oxide film or a metal film on a substrate (hereinafter referred to as a wafer). In a vertical substrate processing apparatus, a boat is provided as a substrate holder for holding wafers in multiple stages in a processing chamber, and a processing gas is supplied to the substrates while the substrates are held in the boat, thereby processing the substrates. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] WO2024 / 003997 [Patent Document 2] Japanese Patent Publication No. 2022-52622 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in conventional technology, the processing gas is supplied toward the center of the wafer, which reduces the flow area of ​​the processing gas, and depending on the process, it may not be possible to adequately control the flow of the processing gas within the processing vessel.

[0005] The present disclosure provides a technique that can increase the flow path area of ​​a process gas. [Means for solving the problem]

[0006] According to one aspect of the present disclosure, there is provided a technology including an injection device that is disposed to the side of a substrate in a processing vessel that accommodates the substrate, extends along a direction perpendicular to the substrate, and injects gas onto the substrate, the injection device having a cylindrical first nozzle and a cylindrical second nozzle, each of the first nozzle and the second nozzle having a flat surface formed on the side facing the substrate, two surfaces connected to either side of the flat surface, a plurality of first injection holes that are arranged on the flat surface along a direction parallel to the substrate and inject gas in substantially the same direction, and second injection holes that are arranged on at least one of the two surfaces and inject gas in a direction inclined with respect to the same direction. [Effects of the Invention]

[0007] According to the present disclosure, it is possible to increase the flow path area of ​​the process gas. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a front cross-sectional view of a substrate processing apparatus according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a view taken along the arrow AA in FIG. [Figure 3] FIG. 3 is a view taken along the arrow BB in FIG. 2. [Figure 4] FIG. 2 is an enlarged cross-sectional plan view showing a main part of the substrate processing apparatus according to an embodiment of the present disclosure. [Figure 5] FIG. 1 is a perspective view of an injection device according to an embodiment of the present disclosure. [Figure 6] FIG. 2 is a block diagram illustrating a control system of a control unit of the substrate processing apparatus according to an embodiment of the present disclosure. [Figure 7] 1 is a flowchart illustrating a substrate processing process according to an embodiment of the present disclosure. [Figure 8] 1 is a graph illustrating the relationship between gas nozzle position and pressure according to an embodiment of the present disclosure. [Figure 9]1A and 1B show a gas nozzle according to an embodiment of the present disclosure, in which (A) shows the in-plane pressure distribution when no second injection holes are provided, (B) shows the in-plane pressure distribution when a second injection hole is provided, (C) shows the in-plane flow velocity distribution when no second injection holes are provided, and (D) shows the in-plane flow velocity distribution when a second injection hole is provided. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 9. Note that the drawings used in the following description are all schematic, and the dimensional relationships, ratios, etc. of the elements shown in the drawings do not necessarily match those of reality. Furthermore, the dimensional relationships, ratios, etc. of the elements do not necessarily match between multiple drawings.

[0010] Unless otherwise specified in the specification, each element is not limited to one, and may be present in plural. In the drawings, substantially identical elements are denoted by the same reference numerals, and redundant explanations in the specification will be omitted.

[0011] Furthermore, the term "wafer" used in this specification may refer to the wafer itself or to a laminate of the wafer and a predetermined layer or film formed on its surface. The term "surface of a wafer" used in this specification may refer to the surface of the wafer itself or to the surface of a predetermined layer or the like formed on the wafer. When described in this specification, "forming a predetermined layer on a wafer" may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. When used in this specification, the term "substrate" is synonymous with the term "wafer".

[0012] Furthermore, the term "agent" used in this specification includes at least one of a gaseous substance and a liquid substance. Liquid substances include mist-like substances. That is, film-forming agents, modifying agents, and etching agents may contain a gaseous substance, a liquid substance such as a mist-like substance, or both.

[0013] Furthermore, in this specification, when a numerical range such as "1 to 2000 Pa" is expressed, it means that the lower limit and the upper limit are included in the range. Therefore, for example, "1 to 2000 Pa" means "1 Pa or more and 2000 Pa or less." The same applies to other numerical ranges. Furthermore, when a numerical value includes "0," "0" means that the substance, such as gas, is not supplied. For example, when the gas supply flow rate includes 0 slm, 0 slm means that the gas is not supplied. This also applies to other substances in the following explanation.

[0014] <Overall configuration of substrate processing equipment> First, the overall configuration of a substrate processing apparatus 1 according to this embodiment will be described with reference to Figures 1 to 6. Note that the up-down direction H of the apparatus indicates the vertical direction, the width direction W of the apparatus indicates the horizontal direction, and the depth direction D of the apparatus indicates the horizontal direction.

[0015] As shown in Fig. 1, the substrate processing apparatus 1 includes a control unit 2 that controls each unit and a processing furnace 3, and the processing furnace 3 has a heater 4 as a heating means. The heater 4 is cylindrical and is installed in the vertical direction of the apparatus by being supported on a heater base (not shown). The heater 4 also functions as an activation mechanism that activates the processing gas with heat. The control unit 2 will be described in detail later.

[0016] A reaction tube 5 constituting a processing vessel for accommodating substrates therein is arranged upright inside the heater 4 and concentrically with the heater 4. The reaction tube 5 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC). The substrate processing apparatus 1 is a so-called hot-wall type.

[0017] As shown in Fig. 2, the reaction tube 5 has a cylindrical inner tube 6 and a cylindrical outer tube 7 provided so as to surround the inner tube 6. That is, the outer tube 7 constitutes the reaction tube 5 together with the inner tube 6. The outer tube 7 surrounds the inner tube 6, thereby forming a gap as an exhaust space S between the cylindrical part and the outer tube 7. The inner tube 6 is disposed concentrically with the outer tube 7. The inner tube 6 is an example of a tube member.

[0018] The inner tube 6 has a covered upper portion and a cylindrical sidewall for accommodating a plurality of substrates therein. Specifically, as shown in FIG. 1, the inner tube 6 is formed in a ceiling-equipped shape with an open lower end and a flat upper end closed by a wall. The outer tube 7 is also formed in a ceiling-equipped shape with an open lower end and a flat upper end closed by a wall. Furthermore, as shown in FIG. 2, a supply buffer 8 serving as a nozzle chamber is formed in the exhaust space S formed between the inner tube 6 and the outer tube 7. Details of the supply buffer 8 will be described later.

[0019] As shown in Fig. 1, a processing chamber 11 for processing wafers 9 as substrates is formed inside the inner tube 6. The processing chamber 11 can accommodate a boat 12, which is an example of a substrate holder capable of holding wafers 9 in a horizontal position with their centers aligned and aligned vertically in multiple stages, and the inner tube 6 surrounds the accommodated wafers 9. The multiple wafers 9 are arranged inside the cylindrical portion of the inner tube 6 along the axial direction of the cylindrical portion. Details of the inner tube 6 will be described later.

[0020] The lower end of the reaction tube 5 is supported by a cylindrical manifold 13. The manifold 13 is made of a metal such as a nickel alloy or stainless steel, or a heat-resistant material such as SiO2 or SiC. A flange is formed at the upper end of the manifold 13, and the lower end of the outer tube 7 is placed on this flange. An airtight member 14 such as an O-ring is disposed between this flange and the lower end of the outer tube 7, making the inside of the reaction tube 5 airtight.

[0021] A seal cap 15 is airtightly attached to the opening at the lower end of the manifold 13 via an airtight member 16 such as an O-ring, and the opening side at the lower end of the reaction tube 5, i.e., the opening of the manifold 13, is airtightly closed. The seal cap 15 is made of a metal such as a nickel alloy or stainless steel and is formed in a disk shape. The seal cap 15 may be configured so that its outside is covered with a heat-resistant material such as SiO2 or SiC.

[0022] A boat support stand 17 for supporting the boat 12 is provided on the seal cap 15. The boat support stand 17 is made of a heat-resistant material such as SiO2 or SiC and functions as a heat insulating portion.

[0023] The boat 12 is erected on a boat support stand 17. The boat 12 is made of a heat-resistant material such as SiO2 or SiC. As shown in Fig. 1, the boat 12 has a bottom plate (not shown) fixed to the boat support stand 17 and a top plate disposed above the bottom plate, and a plurality of support columns 12a are installed between the bottom plate and the top plate.

[0024] The boat 12 holds a plurality of wafers 9 to be processed in the processing chamber 11 in the inner tube 6. As shown in Fig. 1, the plurality of wafers 9 are supported by supports 12a of the boat 12 with the wafers 9 held horizontally at a fixed interval from one another and with their centers aligned. The loading direction of the plurality of wafers 9 is the axial direction of the reaction tube 5. In other words, the centers of the wafers 9 are aligned with the central axis of the boat 12, and the central axis of the boat 12 coincides with the central axis of the reaction tube 5.

[0025] A rotation mechanism 18 for rotating the boat is provided below the seal cap 15. A rotation shaft 19 of the rotation mechanism 18 passes through the seal cap 15 and is connected to the boat support base 17, and the rotation mechanism 18 rotates the boat 12 via the boat support base 17, thereby rotating the wafers 9.

[0026] The seal cap 15 is vertically raised and lowered by an elevator 21 serving as a lifting mechanism provided outside the reaction tube 5 , and the boat 12 can be carried in and out of the processing chamber 11 .

[0027] The manifold 13 is provided with a plurality of nozzle supports that support a first gas nozzle 22, a second gas nozzle 23, a third gas nozzle 24, a fourth gas nozzle 25, a fifth gas nozzle 26, and a sixth gas nozzle 27, which supply gas into the processing chamber 11. In this embodiment, a nozzle support is provided to support each gas nozzle. In FIG. 1 , only the first gas nozzle 22, the first nozzle support 28, and the second nozzle support 29 are illustrated. The nozzle supports are made of a material such as a nickel alloy or stainless steel. In the following description, each gas nozzle will also be simply referred to as a nozzle. Each gas nozzle extends to the side of the wafer 9 held in the boat 12, in a direction perpendicular to the wafer 9.

[0028] Gas supply pipes 31, 32, 33, 34, 35, and 36 that supply gas into the processing chamber 11 are connected to one end of the nozzle support. A first gas nozzle 22, a second gas nozzle 23, a third gas nozzle 24, a fourth gas nozzle 25, a fifth gas nozzle 26, and a sixth gas nozzle 27 are connected to the other end of the nozzle support. Gas supply pipe 31 is connected to gas supply pipe 37, gas supply pipe 32 is connected to gas supply pipe 38, gas supply pipe 33 is connected to gas supply pipe 39, and gas supply pipe 35 is connected to gas supply pipe 41. Each of the gas nozzles 22 to 27 is made of a heat-resistant material such as SiO2 or SiC. The gas nozzles 22 to 27 will be described in detail below.

[0029] (gas supply pipe) The gas supply pipes 31 and 37 communicate with the first gas nozzle 22 via the first nozzle support 28. The gas supply pipes 32 and 38 communicate with the second gas nozzle 23 via the second nozzle support 29. The gas supply pipes 33 and 39 communicate with the third gas nozzle 24 via the nozzle support.

[0030] Furthermore, the gas supply pipe 34 communicates with the fourth gas nozzle 25 via a nozzle support. The gas supply pipes 35 and 41 communicate with the fifth gas nozzle 26 via a nozzle support. The gas supply pipe 36 communicates with the sixth gas nozzle 27 via a nozzle support.

[0031] The gas supply pipe 31 is provided with, in order from the upstream side in the gas flow direction, a raw material gas supply source 42 that supplies a first raw material gas as a processing gas, a mass flow controller (MFC) 43 that is an example of a flow rate controller, a valve 44 that is an on-off valve, a tank 45, and a valve 46. The gas supply pipe 32 is provided with, in order from the upstream side in the gas flow direction, a raw material gas supply source 47 that supplies a first raw material gas as a processing gas, an MFC 48, a valve 49, a tank 51, and a valve 52.

[0032] MFC 43 and MFC 48 are a pair of flow rate controllers according to the present disclosure that supply gas to each of a pair of tanks at set flow rates that are set to form a reference accumulation amount as a target amount of gas. Also, valve 46 is an on-off valve that controls fluid communication of gas between first gas nozzle 22 and tank 45, and valve 52 is an on-off valve that controls fluid communication of gas between second gas nozzle 23 and tank 51, and they are a pair of on-off valves according to the present disclosure.

[0033] In addition, when the gas flow rate cannot be limited to the set flow rate, the control valve (not shown) inside the MFC 43, 48 is fully open or fully closed. This is also called a saturated state or an uncontrollable state. In the present disclosure, in a state where the gas flow rate cannot be limited to the set flow rate, the internal control valve may be fully open or fully closed, or may be positioned between fully open and fully closed.

[0034] Although not shown, each of the MFCs 43 and 48 has an orifice and a control valve that controls the gas pressure on the upstream side of the orifice. Both the MFCs 43 and 48 control the gas flow rate by utilizing choked flow of the orifice.

[0035] The tanks 45 and 51 are configured to store the first source gas alone so that the first source gas supplied from the source gas supply sources 42 and 47 is not mixed with the carrier gas.

[0036] Additionally, corresponding pressure sensors 50a and 50b are provided on the upstream side of each of the tanks 45 and 51. The pressure sensors 50a and 50b are a pair of pressure gauges according to the present disclosure that measure the pressure inside each of the tanks 45 and 51 during gas accumulation.

[0037] The gas supply pipe 33 is provided, in order from the upstream direction, with a source gas supply source 53 for supplying a second source gas as a processing gas, an MFC 54, and a valve 55. The gas supply pipe 34 is provided, in order from the upstream direction, with an assist gas supply source 56 for supplying an assist gas as a processing gas, an MFC 57, and a valve 58. The second source gas is also used as a reaction gas, and the assist gas is a different type of gas from both the first source gas and the second source gas.

[0038] The gas supply pipe 35 is provided, in order from the upstream direction, with a source gas supply source 59 for supplying a second source gas as a processing gas, an MFC 61, and a valve 62. The gas supply pipe 36 is provided, in order from the upstream direction, with an assist gas supply source 63 for supplying an assist gas as a processing gas, an MFC 64, and a valve 65.

[0039] A gas supply pipe 37 for supplying an inert gas is connected to the gas supply pipe 31 downstream of the valve 46. The gas supply pipe 37 is provided with, in order from the upstream side, an inert gas supply source 66 for supplying an inert gas as a processing gas, an MFC 67, and a valve 68. The gas supply pipe 32 is connected to the gas supply pipe 32 downstream of the valve 52, and a gas supply pipe 38 for supplying an inert gas. The gas supply pipe 38 is provided with, in order from the upstream side, an inert gas supply source 69 for supplying an inert gas as a processing gas, an MFC 71, and a valve 72.

[0040] Further, a gas supply pipe 39 for supplying an inert gas is connected to the gas supply pipe 33 downstream of the valve 55. The gas supply pipe 39 is provided with, in order from the upstream side, an inert gas supply source 73, an MFC 74, and a valve 75, which supply an inert gas as a processing gas. The gas supply pipe 39 is connected to the gas supply pipe 35 downstream of the valve 62, and a gas supply pipe 41 for supplying an inert gas is connected to the gas supply pipe 41. The gas supply pipe 41 is provided with, in order from the upstream side, an inert gas supply source 76, an MFC 77, and a valve 78, which supply an inert gas as a processing gas. The assist gas supply sources 56 and 63 and the inert gas supply sources 66, 69, 73, and 76 are connected to a common supply source.

[0041] (Supply system to first gas nozzle 22) A first source gas supply system for supplying a first source gas to the first gas nozzle 22 mainly includes the gas supply pipe 31, the gas supply pipe 37, the MFC 43, the MFC 67, the tank 45, the valve 44, the valve 46, and the valve 68. The source gas supply source 42 and the inert gas supply source 66 may also be included in the first source gas supply system.

[0042] (Supply system to second gas nozzle 23) A first source gas supply system for supplying a first source gas to the second gas nozzle 23 mainly includes the gas supply pipe 32, the gas supply pipe 38, the MFC 48, the MFC 71, the tank 51, the valve 49, the valve 52, and the valve 72. The source gas supply source 47 and the inert gas supply source 69 may also be included in the first source gas supply system.

[0043] (Supply system to third gas nozzle 24) A second source gas supply system for supplying a second source gas to the third gas nozzle 24 mainly includes the gas supply pipe 33, the gas supply pipe 39, the MFC 54, the MFC 74, the valve 55, and the valve 75. The source gas supply source 53 and the inert gas supply source 73 may be included in the second source gas supply system.

[0044] (Supply system to fourth gas nozzle 25) An assist gas supply system for only the upper dummy region of two side dummy regions, which will be described later, is mainly composed of the gas supply pipe 34, the MFC 57, and the valve 58. An assist gas supply source 56 may be included in the assist gas supply system.

[0045] (Supply system to fifth gas nozzle 26) A second source gas supply system for supplying a second source gas to the fifth gas nozzle 26 mainly includes the gas supply pipe 35, the gas supply pipe 41, the MFC 61, the MFC 77, the valve 62, and the valve 78. A source gas supply source 59 and an inert gas supply source 76 may also be included in the second source gas supply system.

[0046] (Supply system to sixth gas nozzle 27) An assist gas supply system for only the lower dummy region of the two side dummy regions is mainly composed of the gas supply pipe 36, the MFC 64, and the valve 65. An assist gas supply source 63 may be included in the assist gas supply system.

[0047] (tank) The tanks 45 and 51 have the same volume and can store the source gas alone so that the source gas is not mixed with the carrier gas. The tanks 45 and 51 supply the stored source gas in pulses to the first gas nozzle 22 and the second gas nozzle 23 approximately simultaneously through an on-off valve. The tanks 45 and 51 are a pair of tanks according to the present disclosure. Although it depends on the vapor pressure of the source gas, the internal pressure of the tanks 45 and 51 is usually below atmospheric pressure. The tanks 45 and 51 can be isothermal tanks filled with metal wool or filaments.

[0048] That is, in this embodiment, a flush supply of a high-concentration source gas can be performed. In the flush supply, the source gas stored in the tanks 45, 51 is supplied from the tanks 45, 51 to the reaction tube 5 at a large flow rate. The source gas supplied at a large flow rate is also called a "flash flow." The source gas in the flush flow flows at a relatively high speed over the surface of the wafer 9 inside the cylindrical portion of the inner tube 6 during the film formation process.

[0049] By the flush supply, the entire surface of the wafer 9 is exposed to a high-speed flow of source gas during the film formation process. A high-speed gas flow is one of the most effective methods for promoting gas replacement inside fine structures such as trenches and holes formed on the surface of the wafer 9, and is particularly useful in processing patterned wafers with high aspect ratios.

[0050] The present disclosure is not limited to flush supply of raw material gas, but may also be applied to, for example, a large flow rate supply of ammonia (NH3) or the like as a purge gas using a general MFC.

[0051] (Exhaust system) A main exhaust port 79 is formed in the outer tube 7 of the reaction tube 5. The main exhaust port 79 is formed below an exhaust port 81 of the inner tube 6. A main exhaust slit 82 serving as a first exhaust part is formed in the inner tube 6 of the reaction tube 5. That is, the reaction tube 5 has the main exhaust slit 82 on its side.

[0052] 2, the main exhaust port 79 is arranged so as to be aligned on the same straight line as the main exhaust slit 82 in a plan view. As shown in Fig. 2, each of the pair of sub-exhaust ports is arranged so as to be aligned on the same straight line as the corresponding sub-exhaust slits 83a, 83b in a plan view. The sub-exhaust slits 83a, 83b correspond to the second exhaust section of the present disclosure.

[0053] The main exhaust port 79 communicates the exhaust space S with the outside of the reaction tube 5. The main exhaust port 79 corresponds to the exhaust port of the present disclosure. The main exhaust port 79 is connected to an exhaust duct 84 that sends the raw material gas to the outside.

[0054] A vacuum pump 88 serving as a vacuum exhaust device is connected to the exhaust duct 84 via a pressure sensor 86 that detects the pressure inside the processing chamber 11 and an APC (Auto Pressure Controller) valve 87 serving as a pressure regulator. The exhaust duct 84 downstream of the vacuum pump 88 is connected to a waste gas treatment device (not shown) or the like. This allows the processing chamber 11 to be evacuated so that the pressure inside the processing chamber 11 reaches a predetermined pressure (i.e., vacuum level) by controlling the output of the vacuum pump 88 and the opening of the APC valve 87.

[0055] A main exhaust system is mainly composed of an exhaust duct 84, an APC valve 87, and a pressure sensor 86. A vacuum pump 88 may also be included in the exhaust system.

[0056] Furthermore, a temperature sensor (not shown) serving as a temperature detector is installed inside the reaction tube 5. Based on the temperature information detected by the temperature sensor, the power supplied to the heater 4 is adjusted so that the temperature inside the processing chamber 11 has a desired temperature distribution.

[0057] In this configuration, a boat 12 carrying multiple wafers 9 to be batch-processed in multiple stages is loaded into the processing chamber 11 of the processing furnace 3 by a boat support 17. The wafers 9 loaded into the processing chamber 11 are then heated to a predetermined temperature by a heater 4. An apparatus having such a processing furnace is called a vertical batch apparatus. The multiple wafers accommodated in the processing chamber 11 can be broadly classified into product wafers and side dummy wafers. Product wafers are wafers on which semiconductor devices such as ICs are actually fabricated. Product wafers are positioned in the vertical center of the entire array of arranged wafers. On the other hand, side dummy wafers are wafers used in place of product wafers and are positioned in positions within the entire array of arranged wafers where the quality required for product wafers cannot be ensured, such as at both ends of the product area. Note that within the processing chamber 11, the area where product wafers are placed is referred to as the product area, and the area where side dummy wafers are placed is referred to as the dummy area.

[0058] 2, supply buffer 8 is an area provided on the side wall of the cylindrical portion of inner tube 6 and protrudes outward from the side wall. Supply buffer 8 is divided into three portions 8a, 8b, and 8c along the circumferential direction of the cylindrical portion by partition walls 89a and 89b. Note that each of the divided portions 8a, 8b, and 8c of supply buffer 8 may be used as a nozzle chamber.

[0059] A first gas nozzle 22 and a second gas nozzle 23 for supplying a first source gas are provided in a central portion 8b of the divided portions of the supply buffer 8. The width of the central portion 8b is set to, for example, 1 to 1.2 times the sum of the widths (major diameters described below) of the first gas nozzle 22 and the second gas nozzle 23. This reduces the dead space in the central portion 8b, thereby suppressing backflow of the first source gas. At the boundary between the central portion 8b of the supply buffer 8 and the cylindrical portion, a virtual arc connecting both ends of the cylindrical portion in the circumferential direction and the center C1 of the wafer 9 form a sector. In this embodiment, the central angle of the sector is less than 30°. In the present disclosure, the central angle of the sector can be set arbitrarily.

[0060] At least the first gas nozzle 22 and the second gas nozzle 23 constitute an injection device for injecting the first source gas onto the wafer 9. The injection device may include other gas nozzles 24 to 27, and may include nozzle support parts 28 and 29. It may further include a gas supply system.

[0061] 3, a supply slit 91 is formed in a central portion 8b of supply buffer 8. Supply slit 91 is open across the entire central portion 8b in the up-down direction H of the apparatus and the entire width direction W of the apparatus. Therefore, first gas nozzle 22 and second gas nozzle 23 face wafer 9 inside the cylindrical portion across the entire vertical direction H of the apparatus and the entire width direction W of the apparatus.

[0062] (exhaust slit) 2, multiple exhaust slits, including a main exhaust slit 82 and sub-exhaust slits 83a and 83b, are formed in the side wall of the cylindrical portion. The multiple exhaust slits exhaust the source gas from inside the cylindrical portion. In this embodiment, the number of multiple exhaust slits is three, consisting of one main exhaust slit 82 and two sub-exhaust slits 83a and 83b. In the present disclosure, the number of multiple exhaust slits may be at least two or more.

[0063] (Main exhaust slit) The main exhaust slit 82 is formed in the side wall of the cylindrical portion on the opposite side of the supply buffer 8 with respect to the center C 1 of the wafer 9 .

[0064] (Secondary exhaust slit) The two sub-exhaust slits 83a, 83b are open on either side of an imaginary vertical plane α set inside the cylindrical portion. The imaginary vertical plane α is a plane perpendicular to the wafer 9, and as shown in Figure 2, is set so as to pass through the circumferential center of the cylindrical portion at the boundary between the supply buffer 8 and the cylindrical portion and the axis of the cylindrical portion (the center of the wafer 9) in a plan view. The axis of the cylindrical portion overlaps with the center of the wafer 9.

[0065] The two sub-exhaust slits 83a, 83b form a pair of exhaust slits, sandwiching the main exhaust slit 82 at the same height as the main exhaust slit 82. In a plan view, imaginary lines L are set connecting the centers of the sub-exhaust slits 83a, 83b and the center C1 of the wafer 9. In this embodiment, the angle between the imaginary line L and the imaginary vertical plane α is an obtuse angle. Note that this angle is measured from the supply buffer 8 side. In the present disclosure, the angle between the imaginary line L and the imaginary vertical plane α is not limited to an obtuse angle.

[0066] 2, the width of each of the two sub-exhaust slits 83a, 83b in the circumferential direction of the cylindrical portion is smaller than the width of the main exhaust slit 82. In the present disclosure, the width of the sub-exhaust slits 83a, 83b may be equal to or greater than the width of the main exhaust slit 82.

[0067] In this embodiment, the opening width of the main exhaust slit 82 along the circumferential direction of the cylindrical portion narrows from top to bottom along the axial direction of the cylindrical portion. Similarly, the opening width of each of the pair of auxiliary exhaust slits 83a, 83b along the circumferential direction of the cylindrical portion narrows from top to bottom along the axial direction of the cylindrical portion. In the present disclosure, the opening widths of the main exhaust slit 82 and the pair of auxiliary exhaust slits 83a, 83b along the circumferential direction of the cylindrical portion can be set arbitrarily.

[0068] Furthermore, the sub-exhaust slits 83a and 83b are arranged on the opposite side of the imaginary plane β from the supply buffer 8, and are configured to exhaust the gas supplied from the supply buffer 8 to the outside of the cylindrical portion at a position farther from the imaginary plane β. This allows the gas supplied into the processing chamber 11 to circulate sufficiently within the processing chamber 11. Here, the imaginary plane β is a plane perpendicular to the wafer 9, and as shown in FIG. 2, passes through the axis of the cylindrical portion (the center of the wafer 9) in a plan view, and is set so as to divide the supply buffer 8 from the main exhaust slit 82 and the sub-exhaust slits 83a and 83b.

[0069] <Main part configuration> Next, each gas nozzle in the substrate processing apparatus 1 according to this embodiment will be described in detail. Note that the positions of the gas nozzles 22, 23, 24, 25, 26, and 27 in Fig. 3 are schematic positions for the purpose of explanation and differ from the actual positions inside the processing chamber 11. In the following, the position of each gas nozzle in a plan view refers to the center position of the cylindrical nozzle.

[0070] In the supply buffer 8, a first gas nozzle 22 as a first injection unit, a second gas nozzle 23 as a second injection unit, a third gas nozzle 24 as a third injection unit, a fourth gas nozzle 25 as a fourth injection unit, a fifth gas nozzle 26 as a fifth injection unit, and a sixth gas nozzle 27 as a sixth injection unit are arranged. Among the divided portions of the supply buffer 8, the first gas nozzle 22 and the second gas nozzle 23 are arranged in the central portion, the third gas nozzle 24 and the fourth gas nozzle 25 are arranged in the upper portion 8a with respect to the page plane in FIG. 2 , and the fifth gas nozzle 26 and the sixth gas nozzle 27 are arranged in the lower portion 8c with respect to the page plane in FIG. 2 . The first gas nozzle 22 and the second gas nozzle 23 are configured to be symmetrical with respect to the imaginary vertical plane α. Therefore, the first source gas can be uniformly supplied to the processing chamber 11 from the first gas nozzle 22 and the second gas nozzle 23.

[0071] (1st injection part) First gas nozzle 22 extends in the vertical direction and is disposed opposite main exhaust slit 82, as shown in Fig. 2. Furthermore, as shown in Fig. 5, first gas nozzle 22 is supported by first nozzle support member 28, and is composed of tapered portion 22a whose cross-sectional area gradually increases from bottom to top, and ejection portion 22b which has an oval cross-section and extends upward from the upper end of tapered portion 22a, and the cross-sectional area of ​​ejection portion 22b is uniform over its entire length in the vertical direction.

[0072] The lower end of the tapered portion 22a is circular, and the upper end is oval, the same shape as the ejection portion 22b. The ejection portion 22b has, on the side facing the wafer 9, a flat surface 22c parallel to the major axis direction and perpendicular to the minor axis direction, and two surfaces, i.e., semi-cylindrical surfaces, connected to both sides of the flat surface 22c. The length of the flat surface 22c in the major axis direction is longer than the diameter of the lower end of the tapered portion 22a, and the length (thickness) in the minor axis direction is shorter than the diameter of the lower end of the tapered portion 22a. Furthermore, the length (width) of the flat surface 22c is longer than the length (thickness) of the ejection portion 22b in the minor axis direction.

[0073] The flat surface 22c of the jetting portion 22b faces the main exhaust slit 82. The axis of the jetting portion 22b is eccentric toward the main exhaust slit 82 (the center C1 of the wafer 9) with respect to the center of the lower end of the tapered portion 22a. That is, as shown in Fig. 4, the tapered portion 22a is formed so that the flat surface 22c of the jetting portion 22b protrudes toward the main exhaust slit 82 beyond the lower end of the tapered portion 22a.

[0074] As shown in Figures 4 and 5, ejection part 22b is arranged on flat surface 22c along a direction parallel to the substrate, and has a plurality of first injection holes 92 formed approximately perpendicular to flat surface 22c, and second injection holes 93 formed in the semi-cylindrical surface opposite second gas nozzle 23 and opening in a direction away from second gas nozzle 23, and a third injection hole 94 formed in the center of a top plate that closes the upper end of ejection part 22b.

[0075] The first injection holes 92 are arranged on the same plane, and each first injection hole 92 is approximately perpendicular to the flat surface 22c, so that gas can be ejected in an approximately perpendicular and identical direction or in a substantially identical direction. Furthermore, at least one of the first injection holes 92 directly faces the main exhaust slit 82 across the central axis of the wafer 9. Here, "substantially the same direction" means that the extensions of the injection directions of the first injection holes 92 are aligned to such an extent that they do not intersect within the processing chamber 11.

[0076] The second injection holes 93 are provided in one of the two surfaces connected to the flat surface 22c, and are configured to inject gas in a direction inclined with respect to the injection direction of the first injection holes 92. The arrangement of the injection holes including the first injection holes 92 and the second injection holes 93 does not have mirror symmetry and is therefore asymmetric with respect to any plane perpendicular to the wafer 9. Furthermore, the first source gas is injected from the first injection holes 92 substantially perpendicular to the flat surface 22c, and the first source gas is injected radially through the first injection holes 92 and the second injection holes 93 in a plan view.

[0077] In the present disclosure, the size of the opening of the second injection hole 93 is set to a size that does not generate a steady return flow that passes along the inner wall of the inner tube 6 and passes through an imaginary plane β directly facing the first injection hole 92 on the central axis of the wafer 9 in a direction toward the first injection hole 92. For example, the diameter (hole diameter) of the second injection hole 93 is set to 1 to 4 mm. This suppresses the generation of a steady return flow. Furthermore, the second injection hole 93 is formed at a position offset by an angle θ, for example, 5 to 60°, preferably 15 to 45°, in the horizontal direction from a direction perpendicular to the major axis of the injection portion 22b (the direction in which the first injection hole 92 opens). Furthermore, the distance between adjacent first injection holes 92 is set to be smaller than the distance between the closest first injection hole 92 and second injection hole 93.

[0078] In the present disclosure, first injection holes 92 and second injection holes 93 are arranged in the horizontal direction and are arranged in multiple stages at equal intervals along the vertical direction, and the height of each injection hole 92, 93 corresponds to the wafers 9 arranged in multiple stages. Also, in Fig. 4, two first injection holes 92 are formed in the flat surface 22c of the injection part 22b, but as shown in Fig. 5, the number of first injection holes 92 may be three or four or more. This configuration also applies to the first injection holes 95 and second injection holes 96 of the second gas nozzle 23 described later.

[0079] (2nd injection part) Second gas nozzle 23 has substantially the same shape as first gas nozzle 22. Second gas nozzle 23 is supported by second nozzle support part 29 and is composed of tapered part 23a whose cross-sectional area gradually increases from bottom to top, flat surface 23c extending upward from the upper end of tapered part 23a, and ejection part 23b having an oval cross section and two surfaces (semi-cylindrical surfaces) connected to flat surface 23c. The length (width) of flat surface 23c is longer than the length (thickness) of ejection part 23b in the minor axis direction.

[0080] Flat surface 23c of ejection part 23b faces main exhaust slit 82. Injection part 23b is arranged on flat surface 23c along a direction parallel to the substrate, and has a plurality of first ejection holes 95 formed substantially perpendicular to flat surface 23c, second ejection holes 96 that open in a direction away from first gas nozzle 22 in the semi-cylindrical surface opposite to first gas nozzle 22, and third ejection hole 97 formed in the center of the top plate.

[0081] The first injection holes 95 are arranged on the same plane, and each first injection hole 95 is approximately perpendicular to the flat surface 23c, so that gas can be ejected in an approximately perpendicular and identical direction or in a substantially identical direction. Furthermore, at least one of the first injection holes 95 directly faces the main exhaust slit 82 across the central axis of the wafer 9. Here, "substantially the same direction" means that the extensions of the injection directions of the first injection holes 95 are aligned to such an extent that they do not intersect within the processing chamber 11.

[0082] The second injection holes 96 are provided in one of the two surfaces connected to the flat surface 23c, and are configured to inject gas in a direction inclined with respect to the injection direction of the first injection holes 95. The injection holes including the first injection holes 95 and the second injection holes 96 are arranged asymmetrically with respect to any plane perpendicular to the wafer 9. Furthermore, the first source gas is injected from the first injection holes 95 substantially perpendicular to the flat surface 23c, and the first source gas is injected radially through the first injection holes 95 and the second injection holes 96 in a plan view.

[0083] In the present disclosure, the size of the opening of the second injection hole 96 is set to a size that does not generate a steady return flow that passes along the inner wall of the inner tube 6 and passes through an imaginary plane β directly facing the first injection hole 95 on the central axis of the wafer 9 in a direction toward the first injection hole 95. For example, the diameter (hole diameter) of the second injection hole 96 is set to 1 to 4 mm. This suppresses the generation of a steady return flow. Furthermore, the second injection hole 96 is formed at a position that is 5 to 60 degrees, preferably 15 to 45 degrees, horizontally away from a direction perpendicular to the major axis of the injection portion 23b (the direction in which the first injection hole 95 opens). Furthermore, the distance between adjacent first injection holes 95 is set to be smaller than the distance between the closest first injection hole 95 and second injection hole 96.

[0084] As described above, in the present disclosure, the second injection holes 93 of the first gas nozzle 22 and the second injection holes 96 of the second gas nozzle 23 are configured to eject the first source gas in directions that separate from each other. Furthermore, in the present disclosure, the first gas nozzle 22 and the second gas nozzle 23 have an elongated cylindrical shape with two semi-cylindrical faces connected to a flat face. However, the first gas nozzle 22 and the second gas nozzle 23 are not limited to an elongated cylindrical shape. For example, the first gas nozzle 22 and the second gas nozzle 23 may have a semi-elongated cylindrical shape (a kamaboko shape) with two quarter-cylindrical faces connected to a single flat face. The oval shape may also include a rounded rectangle, a super ellipse, and the like.

[0085] (3rd injection part) The third gas nozzle 24 has at least an injection hole 98 facing the product region of the processing chamber 11. The third gas nozzle 24 supplies the second source gas to the product wafers and dummy wafers through the injection hole 98. The injection hole 98 may be provided in both the product region and the dummy region, or may be provided only in the product region.

[0086] (4th injection part) The fourth gas nozzle 25 has injection holes 99 that supply assist gas only to substrates in the upper dummy region (upper dummy region) among the dummy regions. The number of injection holes 99 in the fourth gas nozzle 25 is one or more. That is, the fourth gas nozzle 25 supplies assist gas to one or more rows of dummy wafers. In the present embodiment, the case where the number of injection holes 99 in the fourth gas nozzle 25 is three has been exemplified, but in the present disclosure, the number can be set to any number greater than one.

[0087] Furthermore, although the present disclosure has exemplified a case in which the injection holes 99 are provided only in the upper dummy region, the injection holes 99 may be provided in both the product region and the dummy region. In this case, the number of injection holes arranged in one row may be changed, for example, by making the number of injection holes in the dummy region greater than the number of injection holes in the product region so that more assist gas is injected into the dummy region than into the product region, or by making the number of injection holes arranged in one row in the dummy region three and the number of injection holes arranged in one row in the product region one.

[0088] (5th injection part) The fifth gas nozzle 26 has at least an injection hole 101 facing the product region of the processing chamber 11. The fifth gas nozzle 26 supplies the second source gas to the product wafers and the dummy wafers through the injection hole 101. The injection hole 101 may be provided in both the product region and the dummy region, or may be provided only in the product region.

[0089] (6th injection part) The sixth gas nozzle 27 has an injection hole (not shown) facing at least the product region. The injection hole may be provided in both the product region and the dummy region, or may be provided only in the product region.

[0090] The sixth gas nozzle 27 supplies an assist gas to the product wafer through the injection holes. The sixth gas nozzle 27 can adjust the in-plane uniformity of all the product wafers.

[0091] In addition, the fourth gas nozzle 25 and the sixth gas nozzle 27 supply an assist gas when the first source gas is being supplied from the first gas nozzle 22 and the second gas nozzle 23, when the second source gas is being supplied from the third gas nozzle 24 and the fifth gas nozzle 26, or when both the first source gas and the second source gas are being supplied.

[0092] In this embodiment, the fourth gas nozzle 25 and the sixth gas nozzle 27 are arranged to sandwich the first gas nozzle 22, the second gas nozzle 23, the third gas nozzle 24, and the fifth gas nozzle 26. The sixth gas nozzle 27 supplies an assist gas when the first gas nozzle 22 and the second gas nozzle 23 supply a first source gas, which is a source gas of a Group 14 element. Examples of the source gas of a Group 14 element include C, Si, Ge, Sn, and Pb. In the present disclosure, the first source gas may be a source gas other than a Group 14 element.

[0093] (Control unit) 6 is a block diagram showing the substrate processing apparatus 1, in which a control unit 2 (so-called controller) of the substrate processing apparatus 1 is configured as a computer. This computer includes a CPU (Central Processing Unit) 102, a RAM (Random Access Memory) 103, a storage device 104, and an I / O port 105.

[0094] The RAM 103, storage device 104, and I / O port 105 are configured to be able to exchange data with the CPU 102 via an internal bus 106. The control unit 2 is connected to an input / output device 107 configured as, for example, a touch panel.

[0095] The storage device 104 is configured by, for example, a flash memory, an HDD (Hard Disk Drive), etc. A control program for controlling the operation of the substrate processing apparatus, a process recipe describing the procedures and conditions of substrate processing (to be described later), etc. are readably stored in the storage device 104.

[0096] The process recipe is a combination of procedures in the substrate processing step described below that are executed by the control unit 2 to obtain a predetermined result, and functions as a program. Hereinafter, the process recipe, control program, etc. will be collectively referred to simply as a program.

[0097] In this specification, when the term "program" is used, it may include only a process recipe, only a control program, or both. The RAM 103 is configured as a memory area (work area) in which programs and data read by the CPU 102 are temporarily stored.

[0098] The I / O port 105 is connected to the above-mentioned MFCs 43, 48, 54, 57, 61, 64, 67, 71, 74, 77, valves 44, 46, 49, 52, 55, 58, 62, 65, 68, 72, 75, 78, pressure sensor 50, APC valve 87, vacuum pump 88, heater 4, temperature sensor, rotation mechanism 18, elevator 21, etc.

[0099] The CPU 102 is configured to read and execute a control program from the storage device 104 and to read a process recipe from the storage device 104 in response to an input of an operation command from the input / output device 107 or the like.

[0100] The CPU 102 is configured to control the flow rate adjustment of various gases by the MFCs 43, 48, 54, 57, 61, 64, 67, 71, 74, and 77, the opening and closing of the valves 44, 46, 49, 52, 55, 58, 62, 65, 68, 72, 75, and 78, and the opening and closing of the APC valve 87, in accordance with the contents of the read process recipe. The CPU 102 is also configured to control the pressure adjustment by the APC valve 87 based on the pressure sensor 50, the start and stop of the vacuum pump 88, and the temperature adjustment of the heater 4 based on the temperature sensor. The CPU 102 is also configured to control the rotation and rotation speed adjustment of the boat 12 by the rotation mechanism 18, the lifting and lowering of the boat 12 by the elevator 21, etc.

[0101] The control unit 2 is not limited to being configured as a dedicated computer, but may also be configured as a general-purpose computer. For example, the control unit 2 of this embodiment can be configured by preparing an external storage device 108 that stores the above-mentioned program and installing the program into a general-purpose computer using this external storage device 108. Examples of external storage devices include magnetic disks such as hard disks, optical disks such as CDs, magneto-optical disks such as MOs, and semiconductor memories such as USB memories.

[0102] <Substrate processing method> Next, an example of substrate processing will be described with reference to Fig. 7. Here, as an example of a semiconductor device manufacturing process, a cycle process for performing film processing by alternately supplying a source (raw material) as a first raw material gas and a reactant (reactive gas) as a second raw material gas to a processing chamber will be described. In this embodiment, an example will be described in which a silicon nitride film (Si3N4 film, hereinafter also referred to as SiN film) is formed on a substrate using a Si raw material gas as an example of a source and a nitrogen-containing gas as a reactant.

[0103] In the film formation process of this embodiment, a SiN film is formed on the wafer 9 by performing a predetermined number of cycles (one or more) of non-simultaneous processes, which include a process of supplying a raw material gas (first raw material gas) to the wafer 9 in the inner tube 6 (film formation process 1: STEP 03 in Figure 7), a purging process of removing remaining raw material gas from the inner tube 6 (film formation process 2: STEP 04 in Figure 7), a process of supplying a nitrogen-containing gas, which is a reactive gas (second raw material gas), to the wafer 9 in the inner tube 6 (film formation process 3: STEP 05 in Figure 7), and a purging process of removing remaining nitrogen-containing gas from the inner tube 6 (film formation process 4: STEP 06 in Figure 7).

[0104] First, in STEP 01 in Fig. 7, wafers 9 are loaded into a boat 12. The boat 12 is carried into the inner tube 6, thereby accommodating the substrates inside the cylindrical portion of the inner tube 6. Next, in STEP 02 in Fig. 7, after the boat 12 is carried into the inner tube 6, the pressure and temperature inside the inner tube 6 are adjusted. Next, four steps of film formation processes 1 to 4 are carried out in sequence. Each step will be described in detail below.

[0105] (Film forming process 1) 7, a flush supply of a first source gas is performed, as shown in Patent Document 2, for example. For example, with valve 44 open and valve 46 closed, the first source gas supplied from source gas supply source 42 is supplied to tank 45 by MFC 43. Similarly, with valve 49 open and valve 52 closed, the first source gas supplied from source gas supply source 47 is supplied to tank 51 by MFC 48. At this time, the accumulation time and flow rate of the first source gas are set so as to be equal to or greater than the minimum amount that enables flush supply in tanks 45 and 51 and to enable the same amount of first source gas to be accumulated.

[0106] When a predetermined amount of the first source gas has accumulated in tank 45 and tank 51, valve 44 is closed and valve 46 is opened to release the first source gas from tank 45 and flush the first source gas to first gas nozzle 22. At the same time, valve 49 is closed and valve 52 is opened to release the first source gas from tank 51 and flush the first source gas to second gas nozzle 23. That is, first gas nozzle 22 and second gas nozzle 23 simultaneously inject the same gas at approximately the same flow rate. Therefore, a large amount of the first source gas can be supplied into processing chamber 11 without increasing the internal pressure of first gas nozzle 22 and second gas nozzle 23.

[0107] When the first raw material gas is supplied, the first raw material gas is simultaneously sprayed from the first gas nozzle 22 and the second gas nozzle 23 toward the wafer 9, and the sprayed raw material gas is exhausted to the outside of the cylindrical portion through the main exhaust slit 82 and the two sub-exhaust slits 83a, 83b.

[0108] The flow rates (substantially the same flow rate) of the first source gas supplied from the first gas nozzle 22 and the second gas nozzle 23 are set to generate an unsteady return flow that passes through an imaginary plane β directly facing the first injection holes 92, 95 on the central axis of the wafer 9, excluding the vicinity of the inner wall of the inner tube 6, in a direction approaching the first injection holes 92, 95. This makes it possible to suppress the generation of a steady return flow. In addition, in the film formation process 1, an inert gas from the inert gas supply sources 66, 69 may be used as a carrier gas.

[0109] The first source gas supplied from the gas supply pipe 31 and the gas supply pipe 32 may be, for example, a Si source gas. The first source gas may be, for example, a Si- and halogen-containing gas. The Si- and halogen-containing gas may be, for example, an inorganic chlorosilane-based gas such as tetrachlorosilane (SiCl4, abbreviated as STC) gas, hexachlorodisilane (Si2Cl6, abbreviated as HCDS) gas, or octachlorotrisilane (Si3Cl8, abbreviated as OCTS). The Si- and halogen-containing gas may be one or more of these. The first source gas corresponds to the first source gas of the present disclosure. In the present disclosure, the first source is not limited to a gas, but may be, for example, a liquid substance such as a mist-like substance.

[0110] Additionally, a fourth gas nozzle 25 and a sixth gas nozzle 27 are used to inject an assist gas such as N2 toward the wafer 9. That is, in this embodiment, the fourth gas nozzle 25 and the sixth gas nozzle 27 supply the assist gas when the first source gas is supplied from the first gas nozzle 22 and the second gas nozzle 23.

[0111] (Film forming process 2) In the film formation process 2, the valves 46 and 52 are closed to stop the supply of the first source gas, and the valves 68 and 72 are opened to supply an inert gas (purge gas) from the inert gas supply sources 66 and 69 to the first gas nozzle 22 and the second gas nozzle 23. Furthermore, by controlling an exhaust pump such as the vacuum pump 88 and the APC valve 87, the pressure inside the reaction tube 5 is evacuated to a predetermined pressure (i.e., vacuum level), for example, 20 Pa or less, and the remaining first source gas is removed from the inner tube 6. At this time, the supply of the assist gas from the fourth gas nozzle 25 and the sixth gas nozzle 27 is continued, further enhancing the effect of purging the remaining first source gas.

[0112] (Film forming process 3) In the film forming process 3, a nitrogen-containing gas is flowed as a second source gas. The valve 55 is opened, and the second source gas from the source gas supply source 53, whose flow rate is adjusted by the MFC 54, is supplied into the inner tube 6 (cylindrical portion) via the third gas nozzle 24. Similarly, the valve 62 is opened, and the second source gas from the source gas supply source 59, whose flow rate is adjusted by the MFC 61, is supplied into the inner tube 6 via the fifth gas nozzle 26. The second source gas supplied from the third gas nozzle 24 and the fifth gas nozzle 26 is exhausted to the outside of the inner tube 6 via the main exhaust slit 82 and the sub-exhaust slits 83a and 83b. The supply of the second source gas causes a reaction between the Si-containing film on the base film of the wafer 9 and the second source gas, forming a SiN film on the wafer 9.

[0113] In this embodiment, for example, the second source gas is ammonia (NH3) gas. NH3 gas is supplied into the inner tube 6 and exhausted through multiple exhaust slits. The supply of NH3 gas causes a reaction between the Si-containing film on the base film of the wafer 9 and the NH3 gas. A SiN film is formed on the wafer 9 through the reaction. In the present disclosure, the second source gas is not limited to a gas, and may be a liquid substance such as a mist-like substance.

[0114] In addition, in the film formation process 3, the supply of the assist gas from the fourth gas nozzle 25 and the sixth gas nozzle 27 continues. That is, in this embodiment, the fourth gas nozzle 25 and the sixth gas nozzle 27 supply the assist gas while the second source gas is being supplied from the third gas nozzle 24 and the fifth gas nozzle 26.

[0115] (Film forming process 4) In the film formation process 4, the valves 55 and 62 are closed to stop the supply of the second source gas, and the valves 75 and 78 are opened to supply an inert gas (purge gas) from the inert gas supply sources 73 and 76 to the third gas nozzle 24 and the fifth gas nozzle 26. Furthermore, by controlling an exhaust pump such as a vacuum pump 88 and an APC valve 87, the pressure inside the reaction tube 5 is evacuated to a predetermined pressure (i.e., vacuum level), for example, 20 Pa or less, and the remaining second source gas is removed from the inner tube 6. At this time, the supply of an assist gas from the fourth gas nozzle 25 and the sixth gas nozzle 27 is continued, further enhancing the effect of purging the remaining second source gas.

[0116] In this embodiment, the above-described film formation steps 1 to 4 constitute one cycle, and in STEP 07 in FIG. 7, the cycle of film formation steps 1 to 4 is performed a predetermined number of times to form a SiN film with a predetermined thickness on the wafer 9. In this embodiment, the film formation steps 1 to 4 are repeated multiple times. In the present disclosure, the film formation steps 1 to 4 may be performed one by one without being repeated.

[0117] After the above-described film formation process is completed, in STEP 08 in Fig. 7, the pressure inside the inner tube 6 is returned to normal pressure (i.e., atmospheric pressure). For example, an inert gas such as N2 gas is supplied into the inner tube 6 and then exhausted. This purges the inner tube 6 with the inert gas, and any gas remaining inside the inner tube 6 is removed from the inner tube 6 (inert gas purge). Thereafter, the atmosphere inside the inner tube 6 is replaced with the inert gas (inert gas replacement), and the pressure inside the inner tube 6 is returned to normal pressure.

[0118] 7, the substrate processing according to this embodiment is completed when the wafer 9 is unloaded from the inner tube 6. The above series of steps constitutes the method for manufacturing a semiconductor device according to this embodiment.

[0119] (Analysis example) Next, the relationship between the pressure inside the first gas nozzle 22 and the second gas nozzle 23 and the flow rate of the first source gas obtained by the substrate processing method performed using the substrate processing apparatus 1 according to this embodiment will be described. Fig. 8 is a graph showing the relationship between the position and the pressure inside the first gas nozzle 22. Note that the first gas nozzle 22 and the second gas nozzle 23 have substantially the same configuration, and therefore, only the first gas nozzle 22 will be described below.

[0120] In Fig. 8, the inlet section indicates tapered portion 22a, and the nozzle hole region indicates injection portion 22b. Also in Fig. 8, solid line 109 indicates the case where the flow rate of the first source gas is 2.0 slm, dashed line 110 indicates the case where the flow rate of the first source gas is 0.0 slm, one-dot chain line 111 indicates the case where the flow rate of the first source gas is 0.5 slm, and two-dot chain line 112 indicates the case where the flow rate of the first source gas is 0.1 slm.

[0121] When the first source gas is supplied, the first source gas flows upward from the lower end of the tapered portion 22a. The cross-sectional area of ​​the tapered portion 22a gradually increases upward, so that the pressure of the first source gas decreases upward in the tapered portion 22a.

[0122] The first raw material gas that has flowed into the injection section 22b flows upward within the injection section 22b while being injected into the inner pipe 6 from the first injection holes 92 and second injection holes 93 of each stage, and the first raw material gas that has not been injected from the first injection holes 92 and second injection holes 93 is released into the inner pipe 6 from the third injection holes 94.

[0123] 8, as the flow rate of the first raw material gas increases, excess energy (i.e., kinetic, position, pressure, and internal energy) of the fluid increases, causing the pressure to rise quadratically toward the upper end (tip) of the injection part 22b. In this case, the flow rate of the first raw material gas injected from the upper first injection hole 92 and the second injection hole 93 is greater than the flow rate of the first raw material gas injected from the lower first injection hole 92 and the second injection hole 93. A difference occurs in the flow rate of the first raw material gas between the upper part (tip) and the lower part (base) of the injection part 22b. Furthermore, when the flow rate of the first raw material gas is increased, for example, when the flow rate is set to 2.0 slm, an oscillatory flow 109a also occurs in the lower part of the injection part 22b.

[0124] On the other hand, if the flow rate of the first source gas is set to an appropriate flow rate for the first gas nozzle 22, for example, a flow rate of 0.1 slm, it is possible to reduce the difference in internal pressure between the upper and lower stages of the injection part 22b. That is, by adjusting the flow rate of the first source gas and the cross-sectional area of ​​the injection part 22b of the first gas nozzle 22, it is possible to suppress an increase in internal pressure at the tip side of the injection part 22b and prevent asymmetric flows of the first source gas.

[0125] In this embodiment, the cross-sectional areas of the injection portion 22b of the first gas nozzle 22 and the injection portion 23b of the second gas nozzle 23 are set so that the flow rate is below a predetermined value that prevents the internal pressure from increasing quadratically from the lower to the upper first injection hole 92 (first injection hole 95).

[0126] Next, the results of measuring the pressure distribution and flow velocity distribution in the horizontal plane at a predetermined height of the first gas nozzle 22 (or the second gas nozzle 23) obtained by the substrate processing method performed using the substrate processing apparatus 1 according to this embodiment will be described as an analysis example, along with the results of a comparative example. The substrate processing apparatus according to the comparative example differs from the substrate processing apparatus 1 according to this embodiment in that it does not have the second injection holes 93 (second injection holes 96). The configuration of the substrate processing apparatus according to the comparative example, other than the second injection holes 93, is the same as that of the substrate processing apparatus 1 according to this embodiment.

[0127] FIG. 9(A) shows the in-plane pressure distribution of the decomposition products of the raw material gas when the second injection holes 93 are not provided, i.e., when the first injection holes 92 are provided only on the flat surface 22c of the injection part 22b, FIG. 9(B) shows the in-plane pressure distribution when the second injection holes 93 are provided, FIG. 9(C) shows the in-plane flow velocity distribution when the second injection holes 93 are not provided, and FIG. 9(D) shows the in-plane flow velocity distribution when the second injection holes 93 are provided.

[0128] 9(A), in the comparative example, all of the first injection holes 92 inject gas in the same or substantially the same direction, forming a narrow gas flow path (main flow path), and the gas is exhausted from the main exhaust slit 82 without diffusing inside the inner pipe 6. For this reason, as shown in FIG. 9(C), a return flow occurs inside the inner pipe 6 to the outside of the main flow path, causing gas to stagnate inside the inner pipe 6 outside the main flow path. Therefore, high resolution and high partial pressure occur outside the main flow path, and there is a risk that the in-plane uniformity of the wafer 9 will deteriorate.

[0129] On the other hand, as shown in FIG. 9(B), in this embodiment, the second injection holes 93 are provided to inject gas in a direction oblique to the flow of gas injected from the first injection holes 92. This widens the gas flow path through the inner tube 6, allowing the gas to diffuse within the inner tube 6 and be exhausted not only through the main exhaust slit 82 but also through the auxiliary exhaust slits 83a and 83b. Therefore, as shown in FIG. 9(D), the gas return flow is reduced, reducing gas stagnation within the inner tube 6. From FIG. 9(D), it can be seen that no return flow occurs that passes through an imaginary plane 113, which is perpendicular to the line connecting the center of the injection device and the center of the main exhaust slit 82 on the central axis of the substrate, in a direction toward the injection device. Therefore, the partial pressure in the inner tube 6 is improved, and the in-plane uniformity of the wafer 9 is improved. Although the flow becomes asymmetric and fluctuates (oscillates) between the left and right sides, the effects are limited and can be further suppressed by optimizing the shapes of the first gas nozzle 22 and the second gas nozzle 23, and in particular the number, position, and orientation of the first injection holes 92 and the second injection holes 93.

[0130] (Action and effect) According to this aspect, one or more of the following effects can be obtained.

[0131] In this embodiment, the first gas nozzle 22 and the second gas nozzle 23 each have three or more injection holes arranged along a direction substantially parallel to the substrate surface, i.e., first injection holes 92, 95 and second injection holes 93, 96 that inject gas in a direction different from the injection direction of the first injection holes 92, 95. Gas is supplied into the inner tube 6 (processing chamber 11) from the first injection holes 92, 95 and the second injection holes 93, 96. This configuration widens the gas flow within the inner tube 6, suppressing backflow. Furthermore, gas retention within the inner tube 6 is suppressed, improving the source gas supply efficiency, improving gas replacement, and improving the partial pressure within the inner tube 6. Furthermore, this configuration improves the in-plane uniformity of the wafer 9 during the film formation process and enables film formation on the side surfaces of fine holes and grooves.

[0132] Furthermore, the first gas nozzle 22 and the second gas nozzle 23 are shaped like an elongated cylinder having a flat surface 22c, and the first injection holes 92, 95 are all provided on the flat surface 22c so that the injection directions are the same or substantially the same. Therefore, the gases injected from the first injection holes 92, 95 can be prevented from joining together and strengthening each other, and the gas flow velocity inside the inner tube 6 can be made uniform.

[0133] Furthermore, the first injection holes 92, 95 provided in the first gas nozzle 22 and the second gas nozzle 23 are configured to inject gas in the same or substantially the same direction. Therefore, even if there is variation in the hole diameter of the first injection holes 92, 95, the effect on the flow velocity distribution can be suppressed, and inter-surface uniformity can be improved.

[0134] Furthermore, first gas nozzle 22 and second gas nozzle 23 are each composed of tapered sections 22a and 23a and injection sections 22b and 23b, and tapered sections 22a and 23a are configured so that the cross-sectional area gradually increases upward. That is, first gas nozzle 22 and second gas nozzle 23 have a flow path area at their upper ends (tip ends) that is larger than the flow path area at their lower ends (base ends), so that an increase in pressure (internal pressure) at the tip ends of first gas nozzle 22 and second gas nozzle 23 can be suppressed.

[0135] Furthermore, the first injection holes 92, 95 and the second injection holes 93, 96 are provided on the same plane, and the heights of the first injection holes 92, 95 and the second injection holes 93, 96 correspond to the respective wafers 9 arranged in multiple stages. Therefore, the flow of gas supplied to each wafer 9 can be made wide and uniform, thereby improving the in-plane and inter-plane uniformity. Furthermore, since at least one of the first injection holes 92, 95 faces the main exhaust slit 82, exhaust of the first source gas within the processing chamber 11 can be promoted and retention of the first source gas can be suppressed.

[0136] In this embodiment, a fourth gas nozzle 25 and a sixth gas nozzle 27, which supply an assist gas, are arranged on either side of the first gas nozzle 22, the second gas nozzle 23, the third gas nozzle 24, and the fifth gas nozzle 26. Therefore, the first source gas and the second source gas can be diluted by the assist gas supplied from the fourth gas nozzle 25 and the sixth gas nozzle 27, thereby improving the supply efficiency of each source gas. Furthermore, the fourth gas nozzle 25 and the sixth gas nozzle 27 can improve gas replacement during the film formation process and can also prevent gas from returning to the supply buffer 8 due to vortices, turbulence, and the like in the processing chamber 11, i.e., prevent backflow.

[0137] In this embodiment, the fourth gas nozzle 25 and the sixth gas nozzle 27 supply an assist gas when the first source gas is supplied from the first gas nozzle 22 and the second gas nozzle 23, or when the second source gas is supplied from the third gas nozzle 24 and the fifth gas nozzle 26. This improves the source gas supply efficiency, improves gas replacement, and suppresses backflow.

[0138] Although the present disclosure has been described based on the above disclosed embodiments, the descriptions and drawings that form part of this disclosure should not be understood to limit the present disclosure. The present disclosure is not limited to the above embodiments, and various modifications are possible within the scope of the gist thereof, such as application to other processes such as oxidation processes.

[0139] For example, in the above-described embodiment, an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at a time has been described. The present disclosure is not limited to the above-described embodiment, and can be suitably applied, for example, to a case where a film is formed using a single-wafer substrate processing apparatus that processes one or several substrates at a time. Furthermore, in the above-described embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace has been described. The present disclosure is not limited to the above-described embodiment, and can be suitably applied to a case where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0140] When using these substrate processing apparatuses, each process can be performed using the same processing procedures and conditions as in the above-described embodiments and modifications, and the same effects as in the above-described embodiments and modifications can be obtained.

[0141] Furthermore, for example, in the present disclosure, the substrate processing that is executed by loading software (programs) by the CPU 102 in the above embodiment may be executed by various processors other than a CPU. Examples of processors in this case include programmable logic devices (PLDs) such as field-programmable gate arrays (FPGAs) whose circuit configuration can be changed after manufacture, and dedicated electrical circuits such as application-specific integrated circuits (ASICs) that are processors having a circuit configuration designed specifically for executing specific processing.

[0142] Furthermore, substrate processing may be performed by one of these various processors, or by a combination of two or more processors of the same or different types (e.g., multiple FPGAs, a combination of a CPU and an FPGA, etc.) Furthermore, the hardware structure of these various processors is, more specifically, an electric circuit that combines circuit elements such as semiconductor elements.

[0143] In addition, in each of the above embodiments, the substrate processing program is described as being pre-stored (installed) in the storage device 104 such as a ROM or storage, but the present disclosure is not limited to this. The program may be provided in a form recorded on a computer-readable recording medium such as a CD-ROM (Compact Disk Read Only Memory), a DVD-ROM (Digital Versatile Disk Read Only Memory), or a USB (Universal Serial Bus) memory. The program may also be downloaded from an external device via a network.

[0144] Furthermore, the present disclosure may be configured by partially combining the configurations included in the above-disclosed multiple embodiments, variations, and aspects. In the present disclosure configured by a combination, the processing procedures and processing conditions executed may be configured similarly to the processing procedures and processing conditions described in the aspects of the present embodiment, for example. The present disclosure includes various embodiments not described above, and the technical scope of the present disclosure is defined only by the invention-specifying matters in the claims that are appropriate from the above description. [Explanation of symbols]

[0145] 1. Substrate processing equipment 5 Reaction tube 6 Inner tube 9 wafers 22 First gas nozzle 23 Second gas nozzle 92 1st injection hole 93 2nd injection hole 95 1st injection hole 96 2nd injection hole

Claims

1. a processing vessel for accommodating a substrate therein; an injection device disposed to a side of the substrate within the processing vessel, extending in a direction perpendicular to the substrate, and injecting gas onto the substrate; the injection device having a cylindrical first nozzle and a cylindrical second nozzle, each of the first nozzle and the second nozzle having a flat surface formed on a side facing the substrate, two surfaces connected to either side of the flat surface, a plurality of first injection holes arranged on the flat surface along a direction parallel to the substrate and injecting gas in substantially the same direction, and second injection holes arranged on at least one of the two surfaces and injecting gas in a direction inclined with respect to the same direction.

2. The substrate processing apparatus according to claim 1 , wherein the first injection holes of the first nozzle and the second nozzle are arranged on the same plane.

3. The substrate processing apparatus according to claim 1 , wherein each of the first nozzle and the second nozzle ejects gas substantially perpendicular to the flat surface.

4. 3. The substrate processing apparatus according to claim 1, wherein the injection holes including the first injection hole and the second injection hole of the first nozzle are arranged asymmetrically with respect to an arbitrary plane perpendicular to the substrate.

5. 3. The substrate processing apparatus according to claim 1, wherein the first nozzle and the second nozzle are configured to be symmetrical with respect to a plane that passes through the approximate center of the substrate and is perpendicular to the substrate.

6. 2. The substrate processing apparatus according to claim 1, further comprising: a first exhaust section that opens directly opposite at least one of the first injection holes of the first nozzle and at least one of the first injection holes of the second nozzle across a central axis of the substrate.

7. 10. The substrate processing apparatus according to claim 1, wherein the size of the opening of the second injection hole is set so as not to generate a steady return flow that passes along an inner wall of the processing vessel and approaches the first injection hole on an imaginary plane directly opposite the first injection hole on a central axis of the substrate.

8. 8. The substrate processing apparatus according to claim 7, wherein the angle formed between the injection directions of the first injection hole and the second injection hole of each of the first nozzle and the second nozzle is set to 5 to 60 degrees, and the diameter of the second injection hole is set to 1 to 4 mm.

9. 8. The substrate processing apparatus according to claim 7, wherein the distance between the first injection holes of each of the first nozzle and the second nozzle is set smaller than the distance between the first injection hole and the second injection hole that are closest to each other.

10. 7. The substrate processing apparatus according to claim 1, wherein a width of the flat surface of each of the first nozzle and the second nozzle is greater than a thickness of each of the first nozzle and the second nozzle in a direction perpendicular to the flat surface.

11. the second exhaust units exhausting gas to the outside of the processing vessel at positions on the central axis of the substrate and farther from a plane directly facing the first injection holes in the processing vessel.

12. 7. The substrate processing apparatus according to claim 1, wherein the first nozzle and the second nozzle simultaneously inject the same gas at approximately the same flow rate.

13. 13. The substrate processing apparatus according to claim 12, wherein the substantially uniform flow rate is a flow rate that generates an unsteady return flow that passes through an imaginary plane that is axially aligned with the substrate and directly faces the first injection hole, in a direction approaching the first injection hole, above the substrate, excluding the vicinity of the inner wall of the processing vessel.

14. 2. The substrate processing apparatus according to claim 1, wherein each of the first nozzle and the second nozzle has the first injection holes and the second injection holes arranged in multiple stages corresponding to a plurality of the substrates arranged in multiple stages with their centers aligned within the processing vessel.

15. 15. The substrate processing apparatus according to claim 14, wherein the cross-sectional area of ​​each of the first nozzle and the second nozzle is set so that the flow rate is equal to or less than a predetermined value that prevents the internal pressure from increasing quadratically from the lower stage toward the first injection hole at the upper end.

16. 2. The substrate processing apparatus according to claim 1, wherein the processing vessel has a nozzle chamber that protrudes in an outer circumferential direction and in which the first nozzle and the second nozzle are disposed, and the width of the nozzle chamber is set to be 1 to 1.2 times the sum of the widths of the first nozzle and the second nozzle.

17. an injection device provided in a processing vessel that accommodates a substrate, extending in a direction perpendicular to the substrate, and injecting gas onto the substrate; the injection device having a cylindrical first nozzle and a cylindrical second nozzle, each of the first nozzle and the second nozzle having a flat surface formed on a side facing the substrate, two surfaces connected to either side of the flat surface, a plurality of first injection holes arranged on the flat surface along a direction parallel to the substrate and injecting gas in substantially the same direction, and second injection holes arranged in at least one of the two surfaces and injecting gas in a direction inclined with respect to the same direction.

18. A substrate processing method comprising the steps of: injecting gas onto a substrate from an injection device provided on a side of the substrate in a processing vessel that accommodates the substrate, the injection device having cylindrical first and second nozzles extending along a direction perpendicular to the substrate; wherein the injection of gas onto the substrate comprises: each of the first and second nozzles injecting gas in substantially the same direction from a plurality of first injection holes arranged along a direction parallel to the substrate on a flat surface formed on a side facing the substrate; and each of the first and second nozzles injecting gas in a direction inclined with respect to the same direction from second injection holes arranged on at least one of two surfaces that are connected to both sides of the flat surface.

19. A method for manufacturing a semiconductor device, comprising the steps of: injecting gas onto a substrate from an injection device provided on a side of the substrate in a processing vessel that accommodates the substrate, the injection device having cylindrical first and second nozzles extending along a direction perpendicular to the substrate; and injecting gas onto the substrate, the step comprising: each of the first and second nozzles injecting gas in substantially the same direction from a plurality of first injection holes arranged along a direction parallel to the substrate on a flat surface formed on a side facing the substrate; and each of the first and second nozzles injecting gas in a direction inclined with respect to the same direction from second injection holes arranged on at least one of two surfaces that are connected to both sides of the flat surface.

20. a program for causing a computer included in a substrate processing apparatus to execute the following steps: a step of injecting gas onto a substrate from an injection device that is provided on a side of a substrate in a processing vessel that accommodates the substrate inside and has cylindrical first and second nozzles that extend along a direction perpendicular to the substrate, wherein the step of injecting gas onto the substrate includes a step of each of the first and second nozzles injecting gas in substantially the same direction from a plurality of first injection holes that are arranged along a direction parallel to the substrate on a flat surface formed on a side facing the substrate, and a step of each of the first and second nozzles injecting gas in a direction inclined with respect to the same direction from second injection holes that are arranged on at least one of two surfaces that are connected to both sides of the flat surface.

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