Substrate processing apparatus and method for manufacturing semiconductor device

Abstract

The present invention provides a substrate processing device, which can reduce the damage to a reaction tube and a substrate when a substrate is processed by plasma, and can generate plasma stably. Provided is a substrate processing device having the following structure, which comprises: a buffer chamber for gas flow before supply to a substrate; at least one pair of discharge electrodes extending substantially parallel in the buffer chamber; and a pair of sheath tubes made of an insulator covering the at least one pair of discharge electrodes respectively in a manner that does not expose the pair of discharge electrodes to the gas, wherein at least one of the pair of discharge electrodes is provided with a metal cap at an end different from the end to which power is fed, the cap having an outer diameter substantially equal to that of the discharge electrode, and a top portion being formed smoothly.

Description

Technical Field

[0001] The present invention relates to a substrate processing device and a method for manufacturing a semiconductor device, and in particular to a substrate processing device and a method for manufacturing a semiconductor device that utilize plasma to process a substrate. Background Art

[0002] One of the semiconductor device manufacturing processes is a film forming process, which uses a CVD (Chemical Vapor Deposition) method or an ALD (Atomic Layer Deposition) method using plasma to deposit a predetermined thin film on a substrate (see Patent Document 1). The CVD method refers to a method of depositing a thin film composed of elements contained in the raw material gas molecules on a substrate to be processed by utilizing the gas phase of a gaseous raw material and the reaction on the surface. In the CVD method, multiple types of raw material gases including multiple elements constituting the film to be formed are simultaneously supplied to the substrate to be processed to form a film. In the case of the ALD method, multiple types of raw material gases including multiple elements constituting the film to be formed are alternately supplied to the substrate to be processed to form a film. In the ALD method, thin film deposition is controlled at the atomic layer level. In addition, plasma is used to promote the chemical reaction of the deposited thin film in the CVD method, or to remove impurities from the thin film, or to assist the chemical reaction of the adsorbed film-forming raw material in the ALD method. Patent Document 2 discloses Si3N4 film formation using the above technology.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2012-94652

[0006] Patent Document 2: Japanese Patent Application Publication No. 2010-62230 Summary of the invention

[0007] With the gradual miniaturization in semiconductor device manufacturing, it is required to form films at lower substrate temperatures. At this time, the high-frequency power used to form plasma is adjusted to make it optimal for film formation conditions. However, if the high-frequency power becomes larger, the damage to the reaction tube and the electrode may also increase, or stable plasma generation may be hindered.

[0008] A main object of the present invention is to provide a technology that can reduce damage to a reaction tube and a substrate when a substrate is processed using plasma and can generate plasma stably.

[0009] In order to achieve the above-mentioned object, the present invention provides a technology, which is composed of: a buffer chamber for circulating gas before supplying to a substrate; at least one pair of discharge electrodes extending substantially parallel to each other in the buffer chamber; and a pair of sheath tubes made of an insulating system respectively covering the at least one pair of discharge electrodes in a manner that does not expose the pair of discharge electrodes to the gas, wherein at least one of the pair of discharge electrodes is provided with a metal cap at an end different from an end to which power is fed, the cap having an outer diameter substantially equal to that of the discharge electrode and a smoothly formed top end portion.

[0010] Effects of the Invention

[0011] According to the present invention, it is possible to provide a substrate processing apparatus capable of reducing damage to a reaction tube and electrodes and performing stable plasma generation, and a method for manufacturing a semiconductor device using the apparatus. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1A This is a cross-sectional view showing the structure of the main parts of the substrate processing apparatus of Example 1.

[0013] Figure 1B It is a diagram showing the structure of a cap at the tip of the discharge electrode of the substrate processing apparatus according to the first embodiment.

[0014] Figure 2 This is a schematic three-dimensional perspective view for explaining the structure of the remote plasma processing device of Example 1.

[0015] Figure 3 This is a diagram showing a schematic longitudinal section of a processing furnace portion used in the remote plasma processing apparatus of Example 1.

[0016] Figure 4 The embodiment 1, Figure 3 A schematic cross-sectional view of the processing furnace taken along line AA is shown.

[0017] Figure 5 This is a block diagram for explaining a controller used in a remote plasma processing apparatus according to Embodiment 1.

[0018] Figure 6 This is a diagram showing a flow chart for explaining the manufacturing process of the silicon nitride film according to the first embodiment.

[0019] Fig. 7A It is a cross-sectional view showing the structure of the main parts of a conventional substrate processing apparatus.

[0020] Figure 7B It is a diagram showing the structure of the tip portion of a discharge electrode in a conventional substrate processing apparatus.

[0021] Description of Reference Numerals

[0022] 1.203 reaction tube

[0023] 2. Processed substrate

[0024] 4 Discharge electrode end

[0025] 5.30 Discharge electrode

[0026] 6 Buffer Chamber

[0027] 8 Oscillator

[0028] 9 Matchers

[0029] 10 Small holes

[0030] 11 Plasma

[0031] 12 Crystal Boat

[0032] 13 Gas inlet

[0033] 14 Sheath

[0034] 15 Gas nozzle

[0035] 16 Casing

[0036] 17, 31 Coil-shaped structure

[0037] 18, 32 outer braid

[0038] 33 Cap

[0039] 101 Substrate processing device

[0040] 200 Wafer

[0041] 202 Treatment furnace

[0042] 280 Controller

[0043] 281 CPU

[0044] 471, 472, 481, 482 Rod electrodes DETAILED DESCRIPTION

[0045] Hereinafter, the modes for carrying out the present invention will be described in sequence, but for better understanding of the present invention, Fig. 7A , Figure 7B The following will explain the problems in the conventional configuration. Fig. 7A (a) and (b) show a cross-sectional view of a reaction chamber portion of a conventional substrate processing apparatus as viewed from above, and a cross-sectional view taken along line aa' thereof. Figure 7B The top end portion of the discharge electrode is shown in an enlarged manner in the cross-sectional view taken along line aa'.

[0046] like Fig. 7AAs shown, a buffer chamber 6 elongated in the vertical direction is provided near the wall surface inside the reaction tube 1, and a discharge electrode 5 covered by a sheath tube 14 and a gas nozzle 15 for obtaining a uniform gas flow in the buffer chamber are provided inside the buffer chamber 6. The sheath tube 14 is composed of two dielectrics. The high-frequency power generated by the oscillator 8 is applied to the discharge electrode end 4, and a plasma 11 is generated between a pair of discharge electrodes 5 in the buffer chamber 6. The plasma 11 excites the reactive gas supplied from the gas nozzle 15, and is supplied to a substrate to be processed (not shown) in the reaction chamber through a nozzle 10 opened on the wall of the buffer chamber 6.

[0047] In addition, as the structure of the discharge electrode 5, Figure 7B As shown, the structure is such that a coil-shaped structure 17 tightly wound around the center is covered on the outside by a member made of a high-melting-point metal wire as a braid 18 .

[0048] At this time, if Figure 7B As shown, the coil-shaped structure 17 on the inner side of the discharge electrode 5 and the braided fabric 18 on the outer side need to be fixed at both ends of the electrode, and are covered by a cylindrical sleeve 16, and are press-fitted and connected. Then, the unnecessary part of the sleeve 16 is cut off to form a shape, but since the cross section is sharp, the high-frequency voltage is concentrated on the cross section of the sleeve 16 of the discharge electrode 5 during discharge, and the damage to the sheath tube 14 as a dielectric tube increases, and micro-through holes are generated, which becomes a factor in shortening the life of the reaction tube 1.

[0049] Hereinafter, embodiments of the present invention that can solve the above-mentioned problems of the substrate processing apparatus of the conventional structure will be described in order with reference to the drawings.

[0050] [Example 1]

[0051] Embodiment 1 is an embodiment of a substrate processing apparatus and a method for manufacturing a semiconductor device using the apparatus, wherein the substrate processing apparatus is configured to include: a box-shaped buffer chamber for circulating gas before supply to a substrate; a pair of rod-shaped discharge electrodes extending approximately parallel to each other in the buffer chamber; and a pair of sheath tubes made of an insulating system that respectively cover the pair of rod-shaped electrodes in a manner that does not expose the pair of discharge electrodes to the gas, wherein at least one of the pair of discharge electrodes is provided with a metal cap at an end different from an end to which power is fed, the cap having an outer diameter approximately equal to that of the discharge electrode, and a top end portion being smoothly formed.

[0052] use Figure 1A , Figure 1B The substrate processing apparatus of the first embodiment will be described. Figure 1A(a), (b), and (c) respectively represent the structure of the main parts of the substrate processing apparatus of Example 1 as viewed from above, especially the top cross section of the reaction chamber portion, the AA' cross section, and the BB' cross section in the top cross-sectional view.

[0053] like Figure 1A As shown, a wafer boat 12 is provided inside the reaction tube 1, and the wafer boat 12 can carry a plurality of substrates 2 to be processed in multiple layers at equal intervals. The wafer boat 12 can be brought in and out of the reaction tube 1 by a lifting mechanism (not shown). In addition, a rotating mechanism (not shown) of the wafer boat 12 is provided to improve the uniformity of the processing.

[0054] A buffer chamber 6 elongated in the vertical direction is provided near the wall surface inside the reaction tube 1. A pair of discharge electrodes 5 covered by two sheath tubes 14 which are dielectric tubes and a gas nozzle 15 for obtaining a uniform gas flow in the buffer chamber 6 are provided inside the buffer chamber 6. That is, the reaction tube 1 has a gas nozzle 15 provided in parallel with the arrangement direction of the substrates 2 to be processed, and the first gas is supplied from the gas nozzle.

[0055] like Figure 1A As shown in (b), the gas introduced from the gas inlet 13 is introduced into the buffer chamber 6 from the gas nozzle 15. By covering the discharge electrode 5 with the sheath tube 14 which is a dielectric tube, the plasma 11 is prevented from contacting the surface of the discharge electrode 5, and the surface of the discharge electrode 5 is prevented from being sputtered by the plasma, so that the metal contamination spreads to the substrate 2 to be processed. Figure 1A As shown in (a) and (c) of FIG. 5 , in order to feed power to the discharge electrode 5, the discharge electrode end 4 extends to the outside of the sheath tube 14 which is a dielectric tube. Figure 1A As shown in (c) , the sheath tube 14 is partially bent in order to guide the discharge electrode 5 to the outside.

[0056] By using a high melting point metal such as tungsten, molybdenum, tantalum, or nickel as the discharge electrode 5, the discharge electrode 5 can be used as a discharge electrode without being deteriorated inside the sheath tube 14 made of a dielectric material as a protective tube heated to the same temperature as the substrate 2 to be processed. Figure 1A As shown in (a) of FIG. 1 , a high-frequency power generated by an oscillator 8 is applied to the discharge electrode end 4 via a matching device 9 .

[0057] like Figure 1BAs shown in the figure, the discharge electrode 30 of the present embodiment, which constitutes a pair of discharge electrodes 5, is composed of a core material 31 as a coil-shaped structure and a braided material 32 made of a high melting point metal provided on the outside of the core material 31 and has flexibility. A metal cap 33 is provided at the other end of the discharge electrode 30. The cap 33 has an outer diameter substantially equal to that of the discharge electrode 30 and a smoothly formed tip portion. The metal cap 33 is made of a high melting point metal and presses the core material 31 and the braided material 32. The core material 31 is formed into a coil shape by forming a metal wire, and the cap 33 is made of tungsten, molybdenum, tantalum, or nickel which is a high melting point metal. The braided material 32 has an outer diameter substantially equal to or greater than the inner diameter of the sheath tube 14 in a free state, and its two ends are fixed to the core material 31 in a state where a predetermined tension is applied. Furthermore, when inserted into the sheath tube 14, it can be configured in a manner that matches the inner surface of the sheath tube 14. Thus, the discharge electrode 5 and the sheath tube 14 are in close contact or the gap between them is fixed, and uniform plasma is easily formed in the longitudinal direction. The core material 31 may have a straight metal wire for accurately aligning the length in a manner penetrating from the center in addition to the coiled metal wire.

[0058] like Figure 1B As shown in FIG. 1 , the cap 33 is formed in the shape of a rotating body like a bullet having a maximum diameter substantially the same as the outer diameter of the discharge electrode 30, and has a through hole 35 along the rotation axis (symmetry axis). In other words, the top end of the cap 33 is processed by a curved surface. The core material 31 as a coil-shaped structure and the braided material 32 on the outside thereof are inserted into the through hole 35 of the cap 33, and fixed by a headless screw screwed into a threaded hole 34 passing through between the side of the cap 33 and the through hole 35, and at the same time, the cap 33 itself is also fixed to the top end position of the discharge electrode 30.

[0059] In this way, the discharge electrode 30 of the substrate processing device of this embodiment covers the protrusion of the discharge electrode 30 by the cap 33 covering the top end of the electrode, thereby providing a substrate processing device that can prevent the concentration of high-frequency voltage, reduce damage to the sheath tube 14 composed of a dielectric, and can generate stable plasma.

[0060] In addition, Figure 1A , Figure 1BIn the substrate processing apparatus of this embodiment, which shows its main parts, after the wafer boat is lowered by the lifting mechanism (not shown) and the substrate to be processed 2 is placed on the wafer boat 12, the wafer boat 12 is raised and inserted into the reaction tube 1. Next, the heater (not shown) is powered on to heat the reaction tube 1 and the wafer boat 12, the substrate to be processed 2, etc. inside to a predetermined temperature. At the same time, the inside of the reaction tube 1 is exhausted by the pump (not shown). After the temperature of each part inside the reaction tube 1 reaches a predetermined value, the gas for processing the substrate to be processed is introduced into the gas introduction port 13 while the wafer boat is rotated. The pressure inside the reaction tube 1 is adjusted by the pressure adjustment mechanism (not shown), and when it reaches a predetermined value, the high-frequency power output by the oscillator 8 is supplied to the discharge electrode end 4 through the matching device 9. Thus, the following process is performed: plasma 11 is generated inside the buffer tube 6, and the introduced gas and activated particles are supplied to the rotating substrate to be processed 2 from the small holes 10 provided in the buffer tube 6.

[0061] Next, use Figure 2 to Figure 6 The configuration and operation of a remote plasma processing device will be described as a specific example of a substrate processing device of Embodiment 1. That is, a remote plasma processing device is described as follows, which is a remote plasma processing device that performs batch processing on a plurality of substrates to be processed placed in a reaction chamber, wherein a space for generating plasma is provided in a reaction furnace loaded with substrates to be processed, and a plurality of substrates to be processed are batch processed using electrically neutral active materials generated by plasma generated in the space, and the remote plasma processing device uses a discharge electrode for plasma generation, which is made of a high melting point metal that is difficult to be deteriorated at a processing temperature of the substrates to be processed and has a structure that is difficult to cause electric field concentration at its top portion.

[0062] exist Figure 2 In the embodiment, a material box 110 is used for storing a wafer 200 as an example of a substrate in a substrate processing apparatus 101. The wafer 200 is made of a material such as semiconductor silicon. The substrate processing apparatus 101 has a housing 111, and a material box stage 114 is provided inside the housing 111. The material box 110 is moved onto the material box stage 114 or taken out from the material box stage 114 by an in-process conveying device (not shown).

[0063] The magazine 110 is placed on the magazine stage 114 by the in-process conveying device so that the wafers 200 in the magazine 110 are kept in a vertical position and the wafer inlet and outlet of the magazine 110 are facing upward. The magazine stage 114 is configured to work in the following manner: the magazine 110 is rotated 90° in the longitudinal direction by rotating the magazine 110 clockwise toward the rear of the housing 111, so that the wafers 200 in the magazine 110 are in a horizontal position and the wafer inlet and outlet of the magazine 110 are facing the rear of the housing 111.

[0064] A magazine rack 105 is provided at the substantially central portion of the housing 111 in the front-rear direction. The magazine rack 105 is configured to store a plurality of magazines 110 in multiple layers and rows. The magazine rack 105 is provided with a transfer rack 123 for storing the magazines 110 to be transferred by the wafer transfer mechanism 125.

[0065] A reserve box rack 107 is provided above the box stand 114, and is configured to store the box 110 in reserve. A box conveying device 118 is provided between the box stand 114 and the box rack 105. The box conveying device 118 includes a box elevator 118a that can be raised and lowered while holding the box 110, and a box conveying mechanism 118b as a conveying mechanism. The box conveying device 118 is configured to convey the box 110 between the box stand 114, the box rack 105, and the reserve box rack 107 through the interlocking operation of the box elevator 118a and the box conveying mechanism 118b.

[0066] A wafer transfer mechanism 125 is provided at the rear of the cassette rack 105. The wafer transfer mechanism 125 has a wafer transfer device 125a capable of rotating or linearly moving the wafer 200 in the horizontal direction, and a wafer transfer device elevator 125b for raising and lowering the wafer transfer device 125a. A clamping component 125c for picking up the wafer 200 is provided on the wafer transfer device 125a. The wafer transfer device 125 is configured such that, through the interlocking operation of the wafer transfer device 125a and the wafer transfer device elevator 125b, the clamping component 125c is used as a loading portion for the wafer 200, so that the wafer 200 is loaded (loaded) relative to the wafer boat 217, or unloaded (taken out) from the wafer boat 217.

[0067] A processing furnace 202 for heat-treating the wafer 200 is provided at the upper rear portion of the housing 111, and the lower end of the processing furnace 202 is configured to be opened and closed by a furnace opening and closing gate 147. A wafer boat elevator 115 is provided below the processing furnace 202 to lift and lower a wafer boat 217 relative to the processing furnace 202. An arm 128 is connected to the lifting platform of the wafer boat elevator 115, and a sealing cover 219 is horizontally mounted on the arm 128. The sealing cover 219 is configured to vertically support the wafer boat 217 and to seal the lower end of the processing furnace 202.

[0068] A cleaning unit 134a is provided above the cassette rack 105, and supplies clean air as a cleaned ambient gas. The cleaning unit 134a has a supply fan and a dust filter (not shown) and is configured so that the clean air circulates inside the housing 111. A cleaning unit 134b is provided at the left end of the housing 111 to supply clean air. The cleaning unit 134b also has a supply fan and a dust filter (not shown) and is configured so that the clean air circulates near the wafer transfer device 125a and the wafer boat 217. After the clean air circulates near the wafer transfer device 125a and the wafer boat 217, etc., it is exhausted to the outside of the housing 111.

[0069] Next, explain Figure 2 The main work of the substrate processing device 101. After the magazine 110 is moved onto the magazine stage 114 by the in-process conveying device (not shown), the magazine 110 is placed on the magazine stage 114 in such a way that the wafer 200 is kept in a vertical position on the magazine stage 114 and the wafer inlet and outlet of the magazine 110 are facing upward. Then, the magazine 110 passes through the magazine stage 114 so that the wafer 200 in the magazine 110 is in a horizontal position and the wafer inlet and outlet of the magazine 110 are facing the rear of the housing 111, and rotates 90° in the longitudinal direction to the right to the rear of the housing 111.

[0070] Then, the material box 110 is automatically transported and received to a designated shelf position of the material box rack 105 or the reserve material box rack 107 by the material box conveying device 118, and after temporary storage, is transferred from the material box rack 105 or the reserve material box rack 107 to the transfer rack 123 by the material box conveying device 118, or is directly transported to the transfer rack 123.

[0071] After the magazine 110 is transferred to the transfer rack 123, the wafer 200 is picked up from the magazine 110 through the wafer entrance and exit of the magazine 110 by the clamping member 125c of the wafer transfer device 125a, and loaded (loaded) into the wafer boat 217. The wafer transfer device 125a that has received the wafer 200 on the wafer boat 217 returns to the magazine 110 to load the subsequent wafer 200 into the wafer boat 217.

[0072] After a predetermined number of wafers 200 are loaded into the wafer boat 217, the furnace opening and closing gate 147 closing the lower end of the processing furnace 202 is opened to open the lower end of the processing furnace 202. Then, the wafer boat 217 holding the wafer 200 group is moved (loaded) into the processing furnace 202 by the rising operation of the wafer boat elevator 115, and the lower part of the processing furnace 202 is closed by the sealing cover 219. After loading, any processing is performed on the wafers 200.

[0073] Next, refer to Figure 3 , Figure 4The processing furnace 202 used in the substrate processing apparatus 101 is described below. Figure 3 as well as Figure 4 As shown, a heater 207 is provided on the processing furnace 202 as a heating device (heating mechanism) for heating the wafer 200. The heater 207 has a cylindrical insulating member with a closed top and a plurality of heating wires, and has a unit structure in which the heating wires are provided relative to the insulating member. Inside the heater 207, a quartz reaction tube 203 for processing the wafer 200 is provided concentrically with the heater 207. The reaction tube 203 is equivalent to Figure 1A Reaction tube 1.

[0074] Below the reaction tube 203, a sealing cover 219 is provided as a furnace cover body capable of hermetically sealing the lower end opening of the reaction tube 203. The sealing cover 219 abuts against the lower end of the reaction tube 203 from the lower side in the vertical direction. The sealing cover 219 is made of metal such as stainless steel and is formed in a disc shape. An airtight component (hereinafter referred to as an O-ring) 220 is arranged between the annular flange provided at the lower opening end of the reaction tube 203 and the upper surface of the sealing cover 219, and the two are hermetically sealed. At least, the processing chamber 201 is formed by the reaction tube 203 and the sealing cover 219.

[0075] A wafer boat support 218 for supporting the wafer boat 217 is provided on the sealing cover 219. The wafer boat support 218 functions as a heat insulating portion made of a heat-resistant material such as quartz or silicon carbide, and serves as a support body for supporting the wafer boat. The wafer boat 217 is vertically arranged on the wafer boat support 218. The wafer boat 217 is made of a heat-resistant material such as quartz or silicon carbide. The wafer boat 217 has a bottom plate 210 fixed to the wafer boat support 218 and a top plate 211 arranged thereon, and has a structure in which a plurality of pillars 212 are provided between the bottom plate 210 and the top plate 211 (see Figure 3 ). A plurality of wafers 200 are held on the wafer boat 217. The plurality of wafers 200 are stacked in multiple layers in the axial direction of the reaction tube 203 while being spaced at a fixed interval and maintained in a horizontal position and with their centers aligned, and supported by the support pillars 212 of the wafer boat 217.

[0076] A boat rotating mechanism 267 for rotating the boat is provided on the side of the sealing cover 219 opposite to the processing chamber 201. The rotating shaft 265 of the boat rotating mechanism 267 passes through the sealing cover and is connected to the boat support 218. The rotating mechanism 267 rotates the boat 217 via the boat support 218, thereby rotating the wafers 200.

[0077] The sealing cap 219 is vertically moved up and down by a boat elevator 115 which is an elevating mechanism provided outside the reaction tube 203 , thereby enabling the wafer boat 217 to be carried in and out of the processing chamber 201 .

[0078] In the above processing furnace 202, when a plurality of wafers 200 to be processed in a batch are stacked in multiple layers on a wafer boat 217, the wafer boat 217 is inserted into the processing chamber 201 while being supported by the wafer boat support 218, and the heater 207 heats the wafers 200 inserted into the processing chamber 201 to a predetermined temperature.

[0079] like Figure 3 as well as Figure 4 As shown, three gas supply pipes 310, 320, and 330 are connected for supplying raw material gases. Nozzles 410, 420, and 430 are provided in the processing chamber 201. The nozzles 410, 420, and 430 penetrate the lower part of the reaction tube 203. The gas supply pipe 310 is connected to the nozzle 410, the gas supply pipe 320 is connected to the nozzle 420, and the gas supply pipe 330 is connected to the nozzle 430.

[0080] On the gas supply pipe 310, there are provided, in order from the upstream side, a valve 314 serving as an on-off valve, a liquid mass flow controller 312 serving as a flow control device for the liquid raw material, a vaporizer 315 serving as a vaporization unit (gasification device), and a valve 313 serving as an on-off valve.

[0081] The downstream end of the gas supply pipe 310 is connected to the end of the nozzle 410. The nozzle 410 is arranged to stand up from the lower part of the inner wall of the reaction tube 203 along the upper part toward the loading direction of the wafer 200 in the arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200. The nozzle 410 is configured as an L-shaped long nozzle. A plurality of gas supply holes 411 for supplying raw material gas are provided on the side of the nozzle 410. The gas supply holes 411 are opened in a manner toward the center of the reaction tube 203. The gas supply holes 411 have the same opening area or have an opening area with a change slope set to the area size in the range from the lower part to the upper part, and are arranged at the same pitch.

[0082] Furthermore, the gas supply pipe 310 is provided with an elbow 610 and a valve 612 connected to an exhaust pipe 232 described later between the valve 313 and the vaporizer 315 .

[0083] The gas supply system 301 is mainly composed of a gas supply pipe 310 , a valve 314 , a liquid mass flow controller 312 , a vaporizer 315 , a valve 313 , a nozzle 410 , a bend 610 , and a valve 612 .

[0084] In addition, a carrier gas supply pipe 510 for supplying a carrier gas (inert gas) is connected to the gas supply pipe 310 on the downstream side of the valve 313. The carrier gas supply pipe 510 is provided with a mass flow controller 512 and a valve 513. The carrier gas supply pipe 510, the mass flow controller 512, and the valve 513 mainly constitute a carrier gas supply system (inert gas supply system) 501.

[0085] In the gas supply pipe 310, the liquid raw material is flow-regulated by the liquid mass flow controller 312 and supplied to the vaporizer 315, where it is vaporized and supplied as raw material gas. While the raw material gas is not supplied to the processing chamber 201, the valve 313 is closed, the valve 612 is opened, and the raw material gas flows to the elbow 610 through the valve 612.

[0086] When the raw material gas is supplied to the processing chamber 201, the valve 612 is closed, the valve 313 is opened, and the raw material gas is supplied to the gas supply pipe 310 downstream of the valve 313. On the other hand, the carrier gas is supplied from the carrier gas supply pipe 510 via the valve 513 after the flow rate is adjusted by the mass flow controller 512, and the raw material gas merges with the carrier gas on the downstream side of the valve 313 and is supplied to the processing chamber 201 via the nozzle 410. The gas supply pipe 320 is provided with a mass flow controller 322 as a flow control device and a valve 323 as an opening and closing valve in order from the upstream side.

[0087] The downstream end of the gas supply pipe 320 is connected to the end of the nozzle 420. The nozzle 420 is provided in a buffer chamber 423 which is a gas diffusion space (discharge chamber, discharge space). Electrode protection tubes 451 and 452 described later are also provided in the buffer chamber 423. The nozzle 420, the electrode protection tube 451, and the electrode protection tube 452 are arranged in this order in the buffer chamber 423.

[0088] The buffer chamber 423 is formed by the inner wall of the reaction tube 203 and the buffer chamber wall 424. The buffer chamber wall 424 is provided in the arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200, and is provided in the portion from the lower part to the upper part of the inner wall of the reaction tube 203 along the loading direction of the wafer 200. A gas supply hole 425 for supplying gas is provided on the wall of the buffer chamber wall 424 adjacent to the wafer 200. The gas supply hole 425 is provided between the electrode protection tube 451 and the electrode protection tube 452. The gas supply hole 425 opens toward the center of the reaction tube 203. A plurality of gas supply holes 425 are provided in the range from the lower part to the upper part of the reaction tube 203, each having the same opening area and provided at the same pitch.

[0089] The nozzle 420 is provided at one end side of the buffer chamber 423 in a manner that it rises from the lower part of the inner wall of the reaction tube 203 along the upper part toward the upper side in the loading direction of the wafer 200. The nozzle 420 is configured as a long L-shaped nozzle. A gas supply hole 421 for supplying gas is provided on the side of the nozzle 420. The gas supply hole 421 opens toward the center of the buffer chamber 423. The gas supply holes 421 are provided in a plurality from the lower part to the upper part of the reaction tube 203, similarly to the gas supply holes 425 of the buffer chamber 423. When the pressure difference between the buffer chamber 423 and the nozzle 420 is small, the opening area of ​​each of the plurality of gas supply holes 421 can be set to the same opening area and the same pitch from the upstream side (lower part) to the downstream side (upper part), but when the pressure difference is large, the opening area can be increased or the pitch can be decreased in sequence from the upstream side to the downstream side.

[0090] In the substrate processing apparatus of this configuration, the opening area and the opening pitch of each gas supply hole 421 of the nozzle 420 are adjusted from the upstream side to the downstream side as described above, thereby firstly, the gas having a flow rate difference or a flow rate of substantially the same amount is ejected from each gas supply hole 421. Furthermore, once the gas ejected from each gas supply hole 421 is introduced into the buffer chamber 423, the flow rate difference of the gas is made uniform in the buffer chamber 423.

[0091] That is, the gas ejected from each gas supply hole 421 of the nozzle 420 into the buffer chamber 423 has its particle speed slowed down in the buffer chamber 423, and then ejected from the gas supply hole 425 of the buffer chamber 423 into the processing chamber 201. Thus, when the gas ejected from each gas supply hole 421 of the nozzle 420 into the buffer chamber 423 is ejected from each gas supply hole 425 of the buffer chamber 423 into the processing chamber 201, it becomes a gas having a uniform flow rate and flow velocity.

[0092] Furthermore, the gas supply pipe 320 is provided with an elbow 620 and a valve 622 connected to the exhaust pipe 232 described later between the valve 323 and the mass flow controller 322. The gas supply system 302 is mainly composed of the gas supply pipe 320, the mass flow controller 322, the valve 323, the nozzle 420, the buffer chamber 423, the elbow 620, and the valve 622.

[0093] In addition, a carrier gas supply pipe 520 for supplying a carrier gas (inert gas) is connected to the gas supply pipe 320 on the downstream side of the valve 323. The carrier gas supply pipe 520 is provided with a mass flow controller 522 and a valve 523. The carrier gas supply pipe 520, the mass flow controller 522, and the valve 523 mainly constitute a carrier gas supply system (inert gas supply system) 502. In the gas supply pipe 320, the gas raw material gas is supplied with the flow rate adjusted by the mass flow controller 322.

[0094] When the raw material gas is not supplied to the process chamber 201, the valve 323 is closed, the valve 622 is opened, and the raw material gas is allowed to flow to the elbow 620 via the valve 622. When the raw material gas is supplied to the process chamber 201, the valve 622 is closed, the valve 323 is opened, and the raw material gas is supplied to the gas supply pipe 320 downstream of the valve 323. On the other hand, the carrier gas is supplied from the carrier gas supply pipe 520 via the valve 523 after the flow rate is adjusted by the mass flow controller 522, and the raw material gas merges with the carrier gas on the downstream side of the valve 323 and is supplied to the process chamber 201 via the nozzle 420 and the buffer chamber 423.

[0095] The gas supply pipe 330 is provided with a mass flow controller 332 as a flow control device and a valve 333 as an on-off valve in order from the upstream side. The end of the downstream side of the gas supply pipe 330 is connected to the end of the nozzle 430. The nozzle 430 is provided in a buffer chamber 433 as a gas diffusion space (discharge chamber, discharge space). Electrode protection tubes 461 and 462 described later are also provided in the buffer chamber 433. The nozzle 430, the electrode protection tube 461, and the electrode protection tube 462 are arranged in this order in the buffer chamber 433.

[0096] The buffer chamber 433 is formed by the inner wall of the reaction tube 203 and the buffer chamber wall 434. The buffer chamber wall 434 is provided in the arc-shaped space between the inner wall of the reaction tube 203 and the wafer 200, and is provided in the portion from the lower part to the upper part of the inner wall of the reaction tube 203 along the loading direction of the wafer 200. A gas supply hole 435 for supplying gas is provided on the wall of the buffer chamber wall 434 adjacent to the wafer 200. The gas supply hole 435 is provided between the electrode protection tube 461 and the electrode protection tube 462. The gas supply hole 435 opens toward the center of the reaction tube 203. A plurality of gas supply holes 435 are provided in the range from the lower part to the upper part of the reaction tube 203, each having the same opening area and provided at the same pitch.

[0097] The nozzle 430 is provided at one end side of the buffer chamber 433 in a manner that it rises from the lower part of the inner wall of the reaction tube 203 along the upper part toward the upper side in the loading direction of the wafer 200. The nozzle 430 is configured as a long L-shaped nozzle. A gas supply hole 431 for supplying gas is provided on the side of the nozzle 430. The gas supply hole 431 opens toward the center of the buffer chamber 433. The gas supply holes 431 are provided in a plurality from the lower part to the upper part of the reaction tube 203, similarly to the gas supply holes 435 of the buffer chamber 433. When the pressure difference between the buffer chamber 433 and the nozzle 430 is small, the opening area of ​​each of the plurality of gas supply holes 431 can be set to the same opening area and the same pitch from the upstream side (lower part) to the downstream side (upper part), but when the pressure difference is large, the opening area can be increased or the pitch can be decreased in sequence from the upstream side to the downstream side.

[0098] In the substrate processing apparatus of this configuration, the opening area and the opening pitch of each gas supply hole 431 of the nozzle 430 are adjusted from the upstream side to the downstream side as described above, thereby firstly, the gas having a flow rate difference or a flow rate of substantially the same amount is ejected from each gas supply hole 431. Furthermore, once the gas ejected from each gas supply hole 431 is introduced into the buffer chamber 433, the flow rate difference of the gas is made uniform in the buffer chamber 433.

[0099] That is, the gas ejected from each gas supply hole 431 of the nozzle 430 into the buffer chamber 433 has its particle speed slowed down in the buffer chamber 433, and then ejected from the gas supply hole 435 of the buffer chamber 433 into the processing chamber 201. Thus, when the gas ejected from each gas supply hole 431 of the nozzle 430 into the buffer chamber 433 is ejected from each gas supply hole 435 of the buffer chamber 433 into the processing chamber 201, it becomes a gas having a uniform flow rate and flow velocity.

[0100] Furthermore, the gas supply pipe 330 is provided with an elbow 630 and a valve 632 connected to the exhaust pipe 232 described later between the valve 333 and the mass flow controller 332. The gas supply system 303 is mainly composed of the gas supply pipe 330, the mass flow controller 332, the valve 333, the nozzle 430, the buffer chamber 433, the elbow 630, and the valve 632.

[0101] In addition, a carrier gas supply pipe 530 for supplying a carrier gas (inert gas) is connected to the gas supply pipe 330 on the downstream side of the valve 333. The carrier gas supply pipe 530 is provided with a mass flow controller 532 and a valve 533. The carrier gas supply pipe 530, the mass flow controller 532, and the valve 533 mainly constitute a carrier gas supply system (inert gas supply system) 503. In the gas supply pipe 330, the gas raw material gas is supplied with the flow rate adjusted by the mass flow controller 332.

[0102] When the raw material gas is not supplied to the process chamber 201, the valve 333 is closed, the valve 632 is opened, and the raw material gas is allowed to flow to the elbow 630 via the valve 632. When the raw material gas is supplied to the process chamber 201, the valve 632 is closed, the valve 333 is opened, and the raw material gas is supplied to the gas supply pipe 330 downstream of the valve 333. On the other hand, the carrier gas is supplied from the carrier gas supply pipe 530 via the valve 533 after the flow rate is adjusted by the mass flow controller 532, and the raw material gas merges with the carrier gas on the downstream side of the valve 333 and is supplied to the process chamber 201 via the nozzle 430 and the buffer chamber 433.

[0103] In the buffer chamber 423, a plurality of layers are arranged from the bottom to the top of the reaction tube 203 along the stacking direction of the wafers 200. Figure 1A , Figure 1B The discharge electrodes 5 of the cap 33 shown in the figure are a pair of elongated rod-shaped electrodes 471 and 472. The rod-shaped electrodes 471 and 472 are respectively arranged parallel to the nozzle 420, and their top ends are formed into a semicircular shape similar to the discharge electrode 30. The rod-shaped electrodes 471 and 472 are respectively formed by Figure 1AThe sheath tube 14 shown is covered and protected by the protective tubes for protecting the electrodes, namely the electrode protective tubes 451 and 452, in the range from the top to the bottom. The height of the buffer chamber 433 is, for example, 500 to 1500 mm, and the lengths of the rod-shaped electrodes 481 and 482 are also of the same degree, shorter than 1 / 4 of the wavelength. The rod-shaped electrode 471 is connected to the high frequency (RF: Radio Frequency) power supply 270 via the matching device 271, and the rod-shaped electrode 472 is connected to the ground wire 272 as a reference potential. As a result, plasma is generated in the plasma generation region between the rod-shaped electrode 471 and the rod-shaped electrode 472. The first plasma generation structure 429 is mainly composed of the rod-shaped electrode 471, the rod-shaped electrode 472, the electrode protective tube 451, the electrode protective tube 452, the buffer chamber 423 and the gas supply hole 425. The first plasma source as a plasma generator (plasma generating unit) is mainly composed of the rod-shaped electrode 471, the rod-shaped electrode 472, the electrode protection tube 451, the electrode protection tube 452, the matching unit 271, and the high-frequency power supply 270. The first plasma source functions as an activation mechanism that activates the gas into plasma. The buffer chamber 423 functions as a plasma generating chamber.

[0104] In the buffer chamber 433, a rod-shaped electrode 481 and a rod-shaped electrode 482 having an elongated structure are arranged in the range from the bottom to the top of the reaction tube 203 along the stacking direction of the wafers 200. The rod-shaped electrode 481 and the rod-shaped electrode 482 are respectively arranged in parallel with the nozzle 430, and the rod-shaped electrode 481 and the rod-shaped electrode 482 are respectively covered and protected by protection tubes, that is, electrode protection tubes 461 and 462, which protect the electrodes in the range from the top to the bottom. The rod-shaped electrode 481 is connected to the high-frequency power supply 270 via the matching device 271, and the rod-shaped electrode 482 is connected to the ground line 272 as a reference potential. The second plasma generation structure 439 is mainly composed of the rod-shaped electrode 481, the rod-shaped electrode 482, the electrode protection tube 461, the electrode protection tube 462, the buffer chamber 433 and the gas supply hole 435. The second plasma source as a plasma generator (plasma generating unit) is mainly composed of the rod-shaped electrode 481, the rod-shaped electrode 482, the electrode protection tube 461, the electrode protection tube 462, the matching unit 271, and the high-frequency power supply 270. The second plasma source functions as an activation mechanism that activates the gas into plasma. The buffer chamber 433 functions as a plasma generating chamber.

[0105] In addition, the plasma generated by the substrate processing device of this structure is called remote plasma. Remote plasma refers to the plasma processing performed by transferring the plasma generated between the electrodes to the surface of the object to be processed by the flow of gas, etc. In this embodiment, two rod-shaped electrodes 471 and 472 are accommodated in the buffer chamber 423, and two rod-shaped electrodes 481 and 482 are accommodated in the buffer chamber 433, thereby forming the following structure: ions that damage the wafer 200 are difficult to leak into the processing chamber 201 outside the buffer chambers 423 and 433. In addition, an electric field is generated in a manner of surrounding the two rod-shaped electrodes 471 and 472 (that is, in a manner of surrounding the electrode protection tubes 451 and 452 that respectively accommodate the two rod-shaped electrodes 471 and 472), and an electric field is generated in a manner of surrounding the two rod-shaped electrodes 481 and 482 (that is, in a manner of surrounding the electrode protection tubes 461 and 462 that respectively accommodate the two rod-shaped electrodes 481 and 482), and plasma is generated. The active material contained in the plasma is supplied from the outer periphery of the wafer 200 toward the center of the wafer 200 through the gas supply holes 425 of the buffer chamber 423 and the gas supply holes 435 of the buffer chamber 433. In addition, if a vertical batch processing apparatus is used in which a plurality of wafers 200 are stacked in a stacked shape so that the main surfaces are parallel to the horizontal plane as in the present embodiment, the buffer chambers 423 and 433 are arranged at positions close to the inner wall surface of the reaction tube 203, that is, close to the wafer 200 to be processed, and as a result, the generated active material is easily allowed to reach the surface of the wafer 200 without losing its activity.

[0106] like Figure 3 , 4 As shown, an exhaust port 230 is provided at the lower part of the reaction tube. The exhaust port 230 is connected to an exhaust pipe 231. The gas supply hole 411 of the nozzle 410 and the exhaust port 230 are provided at opposite positions (180 degrees opposite sides) across the wafer 200. In this way, the raw material gas supplied from the gas supply hole 411 flows in a manner that crosses the main surface of the wafer 200 toward the exhaust pipe 231, so that the raw material gas is easily and evenly supplied from the entire surface of the wafer 200, and a uniform film can be formed on the wafer 200.

[0107] According to the substrate processing apparatus of this configuration, there is a first plasma source mainly composed of a rod-shaped electrode 471, a rod-shaped electrode 472, an electrode protection tube 451, an electrode protection tube 452, a matching device 271, and a high-frequency power source 270, and a second plasma source mainly composed of a rod-shaped electrode 481, a rod-shaped electrode 482, an electrode protection tube 461, an electrode protection tube 462, a matching device 271, and a high-frequency power source 270. In order to use plasma and reduce the processing temperature of the wafer 200, it is necessary to increase the high-frequency power when forming plasma, but if the high-frequency power is increased, the damage to the wafer 200 and the formed film will also increase. In contrast, in the substrate processing apparatus of this embodiment, since two plasma sources, the first plasma source and the second plasma source, are provided, a sufficient amount of plasma can be generated even if the high-frequency power supplied to each plasma source is reduced compared to the case where there is only one plasma source. Therefore, when the wafer 200 is processed by plasma, the damage to the wafer 200 and the formed film can be reduced, and the processing temperature of the wafer 200 can also be reduced.

[0108] In addition, the first plasma generating structure 429 mainly composed of the rod-shaped electrode 471, the rod-shaped electrode 472, the electrode protection tube 451, the electrode protection tube 452, the buffer chamber 423 and the gas supply hole 425, and the second plasma generating structure 439 mainly composed of the rod-shaped electrode 481, the rod-shaped electrode 482, the electrode protection tube 461, the electrode protection tube 462, the buffer chamber 433 and the gas supply hole 435 are set to be linearly symmetrical with respect to the line passing through the center of the wafer 200 (the center of the reaction tube 203). Therefore, it is easy to evenly supply the raw material gas from the entire surface of the wafer 200 according to the two plasma generating structures, so that a uniform film can be formed on the wafer 200.

[0109] Moreover, if Figure 1A , Figure 1B As shown, the rod-shaped electrodes 471, 472, 481, and 482 are electrodes having a cap 33, and the cap 33 has a structure whose surface is processed so as to be less likely to cause electric field concentration, thereby reducing damage to the reaction tube and the substrate and enabling stable plasma generation.

[0110] Furthermore, the exhaust port 230 is also provided on a line passing through the center of the wafer 200 (the center of the reaction tube 203), so that plasma can be easily and evenly supplied from the entire surface of the wafer 200, and a uniform film can be formed on the wafer 200. Furthermore, the gas supply hole 411 of the nozzle 410 is also provided on a line passing through the center of the wafer 200 (the center of the reaction tube 203), so that the raw material gas can be easily and evenly supplied from the entire surface of the wafer 200, and a uniform film can be formed on the wafer 200.

[0111] Furthermore, the gas supply holes 411, 425, and 435 are arranged in such a manner that the distance between the gas supply hole 411 of the nozzle 410 and the gas supply hole 425 of the buffer chamber 423 and the distance between the gas supply hole 411 of the nozzle 410 and the gas supply hole 435 of the buffer chamber 433 are equal, thereby being able to form a uniform film on the wafer 200.

[0112] If you refer to it again Figure 3 , 4 , an exhaust pipe 231 for exhausting the atmosphere in the processing chamber 201 is connected to the exhaust port 230 at the lower part of the reaction tube. A vacuum pump 246 as a vacuum exhaust device is connected to the exhaust pipe 231 via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 243 as a pressure regulator (pressure adjustment unit), which can perform vacuum exhaust in a manner that the pressure in the processing chamber 201 becomes a specified pressure (vacuum degree). The exhaust pipe 232 on the downstream side of the vacuum pump 246 is connected to an exhaust gas treatment device (not shown) or the like. In addition, the APC valve 243 is an on-off valve that can open and close the valve to perform vacuum exhaust in the processing chamber 201, stop vacuum exhaust, and adjust the conductivity by adjusting the valve opening to adjust the pressure in the processing chamber 201. The exhaust system is mainly composed of the exhaust pipe 231, the APC valve 243, the vacuum pump 246, and the pressure sensor 245.

[0113] A temperature sensor 263 as a temperature detector is provided in the reaction tube 203, and the power supplied to the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263, so that the temperature in the processing chamber 201 becomes a desired temperature distribution. The temperature sensor 263 is L-shaped, inserted through the branch pipe portion 209, and provided along the inner wall of the reaction tube 203.

[0114] A wafer boat 217 is provided in the center of the reaction tube 203. The wafer boat 217 can be raised and lowered (entered and exited) relative to the reaction tube 203 by the wafer boat elevator 115. When the wafer boat 217 is introduced into the reaction tube 203, the lower end of the reaction tube 203 is hermetically sealed by a sealing cap 219 via an O-ring 220. The wafer boat 217 is supported by a wafer boat support table 218. In order to improve the uniformity of the treatment, the wafer boat rotating mechanism 267 is driven to rotate the wafer boat 217 supported by the wafer boat support table 218.

[0115] If you refer to Figure 5The controller 280 includes a display 288 for displaying an operation menu, etc., and an operation input unit 290 including a plurality of keys for inputting various information and operation instructions. In addition, the controller 280 includes a CPU 281 for managing the overall operation of the substrate processing apparatus 101, a ROM 282 for pre-storing various programs including a control program, a RAM 283 for temporarily storing various data, a HDD 284 for storing and holding various data, a display driver 287 for controlling the display of various information on the display 288 and receiving operation information from the display 288, an operation input detection unit 289 for detecting the operation state of the operation input unit 290, and a communication interface (I / F) unit 285 for transmitting and receiving various information to and from various components such as a temperature control unit 291 to be described later, a pressure control unit 294 to be described later, a vacuum pump 246, a wafer boat rotating mechanism 267, a wafer boat elevator 115, mass flow controllers 312, 322, 332, 512, 522, 532, and a valve control unit 299 to be described later.

[0116] The CPU 281, ROM 282, RAM 283, HDD 284, display driver 287, operation input detection unit 289, and communication I / F unit 285 are connected to each other via system bus BUS 286. Therefore, the CPU 281 can access the ROM 282, RAM 283, and HDD 284, and can control the display of various information on the display 288 via the display driver 287, grasp the operation information from the display 288, and control the exchange of various information with each component by the communication I / F unit 285. In addition, the CPU 281 can grasp the operation status of the user with respect to the operation input unit 290 via the operation input detection unit 289.

[0117] The temperature control unit 291 includes a heater 207, a heating power source 250 for supplying power to the heater 207, a temperature sensor 263, a communication I / F unit 293 for exchanging various information such as set temperature information between the controller 280, and a heater control unit 292 for controlling the power supply from the heating power source 250 to the heater 207 based on the received set temperature information and the temperature information from the temperature sensor 263. The heater control unit 292 is also realized by a computer. The communication I / F unit 293 of the temperature control unit 291 and the communication I / F unit 285 of the controller 280 are connected by a cable 751.

[0118] The pressure control unit 294 includes the APC valve 243, the pressure sensor 245, a communication I / F unit 296 for transmitting and receiving various information such as set pressure information and opening and closing information of the APC valve 243 between the controller 280, and the APC valve control unit 295 for controlling the opening and closing and the opening degree of the APC valve 243 based on the received set pressure information, opening and closing information of the APC valve 243, and pressure information from the pressure sensor 245. The APC valve control unit 295 is also realized by a computer. The communication I / F unit 296 of the pressure control unit 294 and the communication I / F unit 285 of the controller 280 are connected by a cable 752.

[0119] The vacuum pump 246, the wafer boat rotating mechanism 267, the wafer boat elevator 115, the liquid mass flow controller 312, the mass flow controllers 322, 332, 512, 522, 532, the high frequency power supply 270 and the communication I / F part 285 of the controller 280 are connected by cables 753, 754, 755, 756, 757, 758, 759, 760, 761, 762 respectively.

[0120] The valve control unit 299 includes valves 313, 314, 323, 333, 513, 523, 533, 612, 622, 632, and a solenoid valve group 298 for controlling the supply of gas to the valves 313, 314, 323, 333, 513, 523, 533, 612, 622, 632 as gas valves. The solenoid valve group 298 includes solenoid valves 297 corresponding to the valves 313, 314, 323, 333, 513, 523, 533, 612, 622, 632, respectively. The solenoid valve group 298 and the communication I / F unit 285 of the controller 280 are connected by a cable 763.

[0121] As described above, the liquid mass flow controller 312, mass flow controllers 322, 332, 512, 522, 532, valves 313, 314, 323, 333, 513, 523, 533, 612, 622, 632, APC valve 243, heating power supply 250, temperature sensor 263, pressure sensor 245, vacuum pump 246, crystal boat rotation mechanism 267, crystal boat elevator 115, high-frequency power supply 270 and other components are connected to the controller 280. The controller 280 performs the following operations respectively: flow control of the liquid mass flow controller 312, mass flow controllers 322, 332, 512, 522, 532, opening and closing control of valves 313, 314, 323, 333, 513, 523, 533, 612, 622, 632; pressure control through opening and closing control of the APC valve 243 and opening adjustment based on pressure information from the pressure sensor 245; temperature control through power supply adjustment from the heating power supply 250 to the heater 207 based on temperature information from the temperature sensor 263; control of the high-frequency power supplied from the high-frequency power supply 270; start and stop control of the vacuum pump 246; rotation speed adjustment control of the wafer boat rotating mechanism 267; and lifting and lowering control of the wafer boat elevator 115, etc.

[0122] Next, an example of a manufacturing process of a semiconductor device (equipment) for manufacturing a large scale integrated circuit (LSI) using the above-mentioned substrate processing apparatus will be described. In the following description, the operations of the various components constituting the substrate processing apparatus are controlled by the controller 280 .

[0123] In the conventional CVD method and ALD method, for example, in the case of the CVD method, multiple types of gases including multiple elements constituting the film to be formed are supplied simultaneously, and in the case of the ALD method, multiple types of gases including multiple elements constituting the film to be formed are supplied alternately. Then, by controlling the processing conditions such as the supply flow rate, supply time, and plasma power during the supply, a silicon oxide film (SiO film) and a silicon nitride film (Si3N4) disclosed in Patent Document 2 are formed. In these technologies, the supply conditions are controlled for the following purposes: for example, in the case of forming an SiO film, the composition ratio of the film becomes O / Si≒2, which is a stoichiometric composition, and for example, in the case of forming an Si3N4 film, the composition ratio of the film becomes N / Si≒1.33, which is a stoichiometric composition.

[0124] On the other hand, the supply conditions can be controlled with the purpose of making the composition ratio of the formed film a predetermined composition ratio different from the stoichiometric composition. In other words, the supply conditions can be controlled with the purpose of making at least one element among the multiple elements constituting the film to be formed excessive relative to the stoichiometric composition compared to the other elements. Film formation can be performed while controlling the ratio of the multiple elements constituting the film to be formed, that is, the composition ratio of the film.

[0125] Hereinafter, an example of a sequence for forming a silicon nitride film having a stoichiometric composition by alternately supplying a plurality of types of gases including different types of elements will be described.

[0126] Here, refer to Figure 6 The following example is used to illustrate: the first element is silicon (Si), the second element is nitrogen (N), BTBAS gas (SiH2(NH(C4H9)2, bis(tert-butylamino)silane) which is a silicon-containing raw material and a liquid raw material is used as the raw material containing the first element, and NH3 gas which is a nitrogen-containing gas is used as the reaction gas containing the second element, and a silicon nitride film as an insulating film is formed on the substrate in the wiring process (BEOL).

[0127] Figure 6 First, the heating power supply 250 that supplies power to the heater 207 is controlled to maintain the temperature in the processing chamber 201 at 200°C or less, more preferably 100°C or less, for example, 100°C.

[0128] Then, after the wafer is loaded, the vacuum pump 246 is started. In addition, the furnace opening and closing gate 147 (see Figure 2 ). The wafer boat 217 supporting a plurality of wafers 200 is lifted by the wafer boat elevator 115 and carried into the processing chamber 201 (wafer boat loading) (step S202). In this state, the sealing cover 219 is in a state of sealing the lower end of the reaction tube 203 via the O-ring 220. Then, the wafer boat 217 is rotated by the wafer boat driving mechanism 267 to rotate the wafers 200.

[0129] Then, open the APC valve 243 and evacuate the processing chamber 201 through the vacuum pump 246 to achieve the desired pressure (vacuum degree). When the temperature of the wafer 200 reaches 100°C and the temperature is stabilized (step S203), the following steps are performed in sequence while maintaining the temperature in the processing chamber 201 at 100°C.

[0130] At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the opening of the APC valve 243 is feedback-controlled (pressure adjustment) based on the measured pressure. In addition, the processing chamber 201 is heated by the heater 207 so that the temperature inside the processing chamber 201 is desired. At this time, the power supply from the heating power supply 250 to the heater 207 is feedback-controlled (temperature adjustment) based on the temperature information detected by the temperature sensor 263 so that the temperature inside the processing chamber 201 is desired.

[0131] Next, a silicon nitride film forming step is performed by supplying BTBAS gas and NH 3 gas (radicals) into the processing chamber 201. In the silicon nitride film forming step, the following four steps (S204 to S207) are repeatedly performed in sequence.

[0132] <BTBAS supply: step S204>

[0133] In step S204, BTBAS is supplied into the processing chamber 201 from the gas supply pipe 310 and the nozzle 410 of the gas supply system 301. The valve 313 is closed, and the valves 314 and 612 are opened. BTBAS is a liquid at room temperature, and the liquid BTBAS is flow-regulated by the liquid mass flow controller 312 and supplied to the vaporizer 315 to be vaporized by the vaporizer 315. Before supplying BTBAS to the processing chamber 201, the valve 313 is closed, the valve 612 is opened, and the BTBAS is allowed to flow to the elbow 610 via the valve 612.

[0134] Furthermore, when BTBAS is supplied to the processing chamber 201, the valve 612 is closed, the valve 313 is opened, BTBAS is supplied to the gas supply pipe 310 downstream of the valve 313, and the valve 513 is opened to supply the carrier gas (N2) from the carrier gas supply pipe 510. The flow rate of the carrier gas (N2) is adjusted by the mass flow controller 512. BTBAS and the carrier gas (N2) merge and mix on the downstream side of the valve 313, and are supplied to the processing chamber 201 through the gas supply hole 411 of the nozzle 410, and are exhausted from the exhaust pipe 231. At this time, the APC valve 243 is appropriately adjusted so that the pressure in the processing chamber 201 is in the range of 50 to 900 Pa, for example, maintained at 300 Pa. The supply amount of BTBAS controlled by the liquid mass flow controller 312 is in the range of 0.05 to 3.00 g / min, for example, set to 1.00 g / min. The time for exposing the wafer 200 to BTBAS is in the range of 2 to 6 seconds, for example 3 seconds. In addition, the heating power supply 250 for supplying power to the heater 207 is controlled to maintain the temperature in the processing chamber 201 at 200°C or less, more preferably 100°C or less, for example 100°C.

[0135] At this time, the gases flowing in the processing chamber 201 are only BTBAS and N2 as an inactive gas, and there are no NH3 radicals. Therefore, BTBAS will not undergo a gas phase reaction, and will undergo a surface reaction (chemical adsorption) with the surface and the bottom film of the wafer 200 to form an adsorption layer or Si-containing layer of the raw material (BTBAS) as the first layer. The Si-containing layer refers to a layer of molecules composed of a part of the dissociated BTBAS molecules, and also includes a thin film composed only of Si. In addition, in the early stage of this process, there is also a situation where the surface of the wafer 200 is covered with a raw material that does not contain Si, such as a carbon film.

[0136] If valve 523 is opened at the same time and a small amount of N 2 (inert gas) flows from carrier gas supply pipe 520 connected to the middle of gas supply pipe 320 , BTBAS can be prevented from entering nozzle 420 , buffer chamber 423 and gas supply pipe 320 on the NH 3 side.

[0137] <Residual Gas Removal: Step S205>

[0138] In step S205, residual gas such as residual BTBAS is removed from the process chamber 201. Valve 313 of gas supply pipe 310 is closed to stop the supply of BTBAS to process chamber 201, and valve 612 is opened to allow BTBAS to flow to elbow 610. At this time, APC valve 243 of exhaust pipe 231 is fully opened, and vacuum pump 246 exhausts the process chamber 201 to below 20 Pa, and residual gas such as residual BTBAS remaining in the process chamber 201 is removed from the process chamber 201. At this time, if inactive gas such as N2 is supplied to the process chamber 201 from gas supply pipe 310, which is a BTBAS supply line, and from gas supply pipes 320 and 330, the effect of removing residual gas such as residual BTBAS can be further improved.

[0139] <Supply of activated NH 3: Step S206 >

[0140] In step S206, NH3 is supplied from the gas supply pipe 320 of the gas supply system 302 to the buffer chamber 423 via the gas supply hole 421 of the nozzle 420, and NH3 is supplied from the gas supply pipe 330 of the gas supply system 303 to the buffer chamber 433 via the gas supply hole 431 of the nozzle 430. At this time, high-frequency power is applied from the high-frequency power supply 270 to between the rod-shaped electrode 471 and the rod-shaped electrode 472 via the matching device 271, so that the NH3 gas supplied to the buffer chamber 423 is excited into plasma, and is supplied from the gas supply hole 425 to the processing chamber 201 as an active material, and is exhausted from the gas exhaust pipe 231. The same is true for the buffer chamber 433.

[0141] NH3 is supplied from the gas supply pipe 320 to the buffer chamber 423 with the flow rate adjusted by the mass flow controller 322, and is supplied from the gas supply pipe 330 to the buffer chamber 433 with the flow rate adjusted by the mass flow controller 332. When NH3 is supplied to the buffer chamber 423, the valve 622 is closed, the valve 323 is opened, NH3 is supplied to the gas supply pipe 320 downstream of the valve 323, and if necessary, the valve 523 is opened to supply a carrier gas (N2) from the carrier gas supply pipe 520. NH3 is supplied to the buffer chamber 423 via the nozzle 420. In addition, when NH3 is supplied to the buffer chamber 433, the valve 632 is closed, the valve 333 is opened, and NH3 is supplied to the gas supply pipe 330 downstream of the valve 333. NH3 is supplied to the buffer chamber 433 via the nozzle 430.

[0142] When NH3 gas is excited by plasma to flow as an active material, the APC valve 243 is appropriately adjusted so that the pressure in the processing chamber 201 is, for example, in the range of 50 to 900 Pa, for example, 500 Pa. The supply flow rate of NH3 gas controlled by the mass flow controller 322 and the mass flow controller 332 is, for example, in the range of 2000 to 9000 sccm. The time for exposing the wafer 200 to the active material obtained by the plasma excitation of NH3 gas, that is, the gas supply time, is, for example, in the range of 3 to 20 seconds, for example, 9 seconds. In addition, the high-frequency power applied between the rod-shaped electrode 471 and the rod-shaped electrode 472 from the high-frequency power supply 270 is configured to have a frequency of, for example, 13.56 MHz or 27.12 MHz, and a power in the range of 20 to 600 W, for example, 200 W. The high-frequency power applied between the rod-shaped electrode 481 and the rod-shaped electrode 482 from the high-frequency power supply 270 is also set in the same manner. NH 3 gas has a high reaction temperature under normal conditions and is difficult to react at the above-mentioned wafer temperature and processing chamber internal pressure. Therefore, it becomes an active substance and flows after being excited by plasma, thereby allowing the temperature of the wafer 200 to be set to the low temperature range set as described above.

[0143] At this time, the gas flowing in the processing chamber 201 contains active substances (NH3*) obtained by plasma excitation of NH3 gas at a predetermined ratio, and no BTBAS gas flows in the processing chamber 201. Therefore, the NH3 gas does not undergo a gas phase reaction, and the NH3 gas that has become an active substance or has been activated reacts with the first layer formed on the wafer 200 in step S204. As a result, the first layer is nitrided and modified into a second layer containing silicon (the first element) and nitrogen (the second element), that is, a silicon nitride layer (Si3N4 layer).

[0144] At the same time, if the valve 513 is opened to allow N 2 (inert gas) to flow from the carrier gas supply pipe 510 connected to the middle of the gas supply pipe 310 , it is possible to prevent NH 3 from entering the nozzle 410 and the gas supply pipe 310 on the BTBAS side.

[0145] <Residual Gas Removal: Step S207>

[0146] In step S207, residual gases such as residual NH3 that have not reacted or helped to implement nitridation are removed from the processing chamber 201. The valve 323 of the gas supply pipe 320 and the valve 333 of the gas supply pipe 330 are closed to stop the supply of NH3 to the processing chamber 201. At this time, the APC valve 243 of the exhaust pipe 231 is fully opened, and the processing chamber 201 is exhausted to below 20 Pa by the vacuum pump 246, and the residual gases such as residual NH3 remaining in the processing chamber 201 are removed from the processing chamber 201.

[0147] The above steps S204 to S207 are regarded as one cycle, and are performed at least once (step S208 ), so that a silicon nitride film having a predetermined film thickness is formed on the wafer 200 .

[0148] If a film forming process for forming a silicon nitride film having a predetermined film thickness is performed, an inert gas such as N2 is supplied into the process chamber 201 and simultaneously exhausted, thereby purging the process chamber 201 with the inert gas (gas purging: step S210). In addition, preferably, after the gas purging removes the residual gas, the APC valve 243 is closed and the valves 513, 523, and 533 are opened to supply the inert gas such as N2 into the process chamber 201, then the valves 513, 523, and 533 are closed to stop the supply of the inert gas such as N2 into the process chamber 201, and the APC valve 243 is opened to evacuate the process chamber 201, and the above operation is repeated.

[0149] Then, the boat rotating mechanism 267 is stopped, and the rotation of the boat 217 is stopped. Then, the valves 513, 523, and 533 are opened to replace the atmosphere in the processing chamber 201 with an inert gas such as N2 (inert gas replacement), and the pressure in the processing chamber 201 is restored to normal pressure (restoration of atmospheric pressure: step S212). Then, the sealing cover 219 is lowered by the boat elevator 115, the lower end of the reaction tube 203 is opened, and the processed wafers 200 are carried out from the lower end of the reaction tube 203 to the outside of the processing chamber 201 while being supported by the boat 217 (boat unloading: step S214). Then, the lower end of the reaction tube 203 is closed by the furnace opening and closing gate 147. Then, the vacuum pump 246 is stopped. Then, the processed wafers 200 are taken out from the boat 217 (wafer unloading: step S216). Thus, one film forming process (batch processing) is completed.

[0150] The present invention is not limited to the above-mentioned embodiments, and includes various modified examples. For example, the above-mentioned embodiments are described in detail for a better understanding of the present invention, and are not limited to having all the structures described. For example, the discharge electrodes are not limited to being arranged in pairs of two, but also include a structure in which three or more are arranged roughly in parallel. Among the three parallel discharge electrodes, the center one is grounded, and the two on both sides are fed in common.

[0151] Furthermore, the above-mentioned components, functions, controllers, CPUs, etc. are described mainly by creating an example of a program to realize part or all of them, but of course, part or all of them can be designed by, for example, an integrated circuit and realized by hardware. In other words, all or part of the functions of the processing unit can also be realized by, for example, an integrated circuit such as ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array) instead of a program.

Claims

1. A substrate processing device, characterized in that: have: a processing chamber for processing a substrate; a buffer chamber for gas flow before supplying to the substrate; at least one pair of discharge electrodes extending substantially parallel to each other within the buffer chamber; and a pair of sheath tubes made of an insulating material respectively covering the pair of discharge electrodes so as not to expose the pair of discharge electrodes to the gas, At least one of the pair of discharge electrodes is provided with a metal cap at an end different from an end to which power is fed. The metal cap has an outer diameter substantially equal to that of the discharge electrode and a tip portion is smoothly formed.

2. The substrate processing device according to claim 1, characterized in that: Each of the pair of discharge electrodes is composed of a core material and a braided material made of a high melting point metal provided outside the core material.

3. The substrate processing device according to claim 2, characterized in that: The cap is made of a high melting point metal and is configured to press-bond the core material and the braided fabric.

4. The substrate processing device according to claim 2, characterized in that: A reaction tube is also provided, in which a plurality of substrates are arranged and accommodated, The buffer chamber is integrally provided with the reaction tube so as to have a surface adjacent to the interior of the reaction tube, and the adjacent surface has one or more first through holes provided in the region where the substrates are arranged and a gas introduction portion communicating with the interior of the buffer chamber.

5. The substrate processing apparatus according to claim 1, wherein: A reaction tube is also provided, in which a plurality of substrates are arranged and accommodated, The discharge electrodes are arranged along the arrangement direction of the substrate. The sheath tube is partially bent to guide the discharge electrode to the outside of the reaction tube.

6. The substrate processing device according to claim 4, characterized in that: The reaction tube also has a gas nozzle arranged parallel to the arrangement direction of the substrates. The first gas from the gas nozzle and the gas containing an electrically neutral active material from the buffer chamber are alternately supplied into the reaction tube to form a predetermined film on the plurality of substrates.

7. The substrate processing apparatus according to claim 1, wherein: The cap is made of tungsten, tantalum, or molybdenum.

8. The substrate processing device according to claim 2, characterized in that: The core material is formed by forming a metal wire into a coil shape.

9. The substrate processing apparatus according to claim 4, characterized in that: The cap includes: a second through hole having a shape of a rotating body and formed along a rotation axis; and a screw for crimping the core material and the braided fabric inserted into the second through hole.

10. The substrate processing apparatus according to claim 1, wherein: The pair of discharge electrodes are each composed of a core material and a braided material made of a high melting point metal provided outside the core material, and have a length shorter than 1 / 4 of the wavelength. The core material is formed by forming a metal wire into a coil shape. The braid has a larger outer diameter than the sheath in a free state, The cap presses and fixes the core material and the knitted fabric while applying a predetermined tension to the knitted fabric.

11. A method for manufacturing a semiconductor device, characterized in that: include: A step of causing the gas before supply to the substrate to flow in a buffer chamber having a pair of discharge electrodes extending substantially parallel to each other in the buffer chamber; A step of exciting the gas in the buffer chamber via a pair of insulating sheath tubes by supplying high-frequency power to the pair of discharge electrodes and converting at least a portion of the gas into plasma or activating the gas, wherein the pair of sheath tubes cover the pair of discharge electrodes respectively in a manner that the pair of discharge electrodes are not exposed to the gas; and a step of treating the substrate with the gas after being transformed into plasma or activated, In the activation step, power is fed to at least one of the pair of discharge electrodes with a metal cap provided at an end different from the end to which power is fed, the cap having an outer diameter substantially equal to that of the discharge electrode and a smoothly formed tip portion.

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