阅读说明：本技术 基板处理装置、半导体装置的制造方法和程序 (Substrate processing apparatus, method of manufacturing semiconductor device, and program ) 是由 原大介 八幡橘 筱崎贤次 山崎一彦 于 2019-03-11 设计创作，主要内容包括：本发明提供一种技术,具有：处理基板的处理室,具备填充并加热第一气体的多个气罐且对处理室内的基板供给第一气体的第一气体供给系统,和控制部,该控制部构成为控制第一气体供给系统,从而能够在切换多个气罐的同时对处理室内的基板供给第一气体。(The present invention provides a technique comprising: a processing chamber for processing a substrate is provided with a first gas supply system for supplying a first gas to the substrate in the processing chamber by filling and heating a plurality of gas tanks for the first gas, and a control unit for controlling the first gas supply system so that the first gas can be supplied to the substrate in the processing chamber while switching the plurality of gas tanks.)

1. A substrate processing apparatus includes:

a processing chamber for processing a substrate,

a first gas supply system which has a plurality of gas tanks that fill and heat a first gas and supplies the first gas to a substrate in the processing chamber, and

a control unit configured to control the first gas supply system so that the first gas can be supplied to the substrate in the processing chamber while switching the plurality of gas tanks.

2. The substrate processing apparatus according to claim 1,

the first gas supply system further has a pressure gauge measuring a pressure in the plurality of gas tanks,

the control unit is configured to control the first gas supply system so that the first gas can be supplied to the substrate in the processing chamber while switching the plurality of gas tanks based on a pressure value measured by the pressure gauge.

3. The substrate processing apparatus according to claim 1, wherein the plurality of gas tanks have the same volume.

4. The substrate processing apparatus according to claim 1, wherein the plurality of gas tanks differ in volume.

5. The substrate processing apparatus according to claim 1,

comprising: a second gas supply system for supplying a second gas to the substrate in the processing chamber,

the first gas is a raw material gas, and the second gas is a reaction gas.

6. The substrate processing apparatus of claim 5, wherein,

comprising: and a plasma generation unit for activating the reaction gas by plasma.

7. A method for manufacturing a semiconductor device includes:

a step of carrying a substrate into a processing chamber of a substrate processing apparatus, the substrate processing apparatus including: a processing chamber for processing the substrate, including a first gas supply system for supplying a first gas to the substrate in the processing chamber and a second gas supply system for supplying a second gas to the substrate in the processing chamber,

a step of supplying the first gas to the substrate in the processing chamber while switching the gas tank, and

and supplying the second gas from the second gas supply system to the substrate in the processing chamber.

8. The method for manufacturing a semiconductor device according to claim 7, wherein,

the substrate processing apparatus has a pressure gauge that measures pressure in the plurality of gas tanks,

in the step of supplying the first gas, the first gas is supplied to the substrate in the processing chamber while switching the plurality of gas tanks based on a pressure value measured by the pressure gauge.

9. The method for manufacturing a semiconductor device according to claim 7, wherein,

the substrate processing apparatus includes: a plasma generating part for activating the second gas by plasma,

in the step of supplying the second gas, the second gas activated by the plasma generation unit is supplied to the substrate.

10. A program for causing a substrate processing apparatus to execute, by a computer, the processes of:

a process of carrying in a substrate into a processing chamber of the substrate processing apparatus, the substrate processing apparatus including: a processing chamber for processing the substrate, including a first gas supply system for supplying a first gas to the substrate in the processing chamber and a second gas supply system for supplying a second gas to the substrate in the processing chamber,

a process of supplying the first gas to the substrate in the processing chamber while switching the gas tank, and

supplying the second gas from the second gas supply system to the substrate in the processing chamber.

11. The program according to claim 10, wherein,

the substrate processing apparatus includes: a pressure gauge measuring a pressure within the plurality of gas tanks,

in the supplying of the first gas, the first gas is supplied to the substrate in the processing chamber while switching the plurality of gas tanks based on a pressure value measured by the pressure gauge.

12. The program according to claim 10, wherein,

the substrate processing apparatus includes: a plasma generating part for activating the second gas by plasma,

and supplying the second gas activated by the plasma generating portion to the substrate in a process of supplying the second gas.

Technical Field

The present disclosure relates to a substrate processing apparatus, a method of manufacturing a semiconductor device, and a program.

Background

As one of the manufacturing processes of a semiconductor device, there is a case where a substrate is carried into a processing chamber of a substrate processing apparatus, and a raw material gas, a reaction gas, or the like supplied into the processing chamber is activated by using plasma to form various films such as an insulating film, a semiconductor film, a conductor film, or the like on the substrate or remove the various films.

Prior art documents

Patent document

Patent document 1: japanese patent laid-open publication No. 2011-216906

Disclosure of Invention

Problems to be solved by the invention

However, the saturated vapor pressure of the reactive gas as the raw material gas is low, and the supply pressure to the apparatus is low. Therefore, it is not possible to increase the flow rate of the flow rate controller, and it is difficult to increase the film formation rate and improve the film quality.

An object of the present disclosure is to provide a technique capable of uniformly processing a substrate.

Means for solving the problems

According to an aspect of the present disclosure, there is provided a technique having: a processing chamber for processing a substrate is provided with a first gas supply system for supplying a first gas to the substrate in the processing chamber by filling and heating a plurality of gas tanks for the first gas, and a control unit for controlling the first gas supply system so that the first gas can be supplied to the substrate in the processing chamber while switching the plurality of gas tanks.

Effects of the invention

According to the present disclosure, a technique capable of uniformly processing a substrate can be provided.

Drawings

Fig. 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in the embodiment of the present disclosure, and is a diagram showing a portion of the processing furnace in a vertical sectional view.

Fig. 2 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in the embodiment of the present disclosure, and is a diagram showing a portion of the processing furnace in a sectional view taken along line a-a of fig. 1.

Fig. 3 (a) is a cross-sectional enlarged view for explaining a buffer structure of a substrate processing apparatus suitably used in the embodiment of the present disclosure, and (b) is a schematic view for explaining a buffer structure of a substrate processing apparatus suitably used in the embodiment of the present disclosure.

Fig. 4 is a schematic configuration diagram of a controller of a substrate processing apparatus suitably used in the embodiment of the present disclosure, and a control system of the controller is shown as a block diagram.

Fig. 5 is a flowchart of a substrate processing step according to an embodiment of the present disclosure.

Fig. 6 is a diagram showing the timing of gas supply in the substrate processing step according to the embodiment of the present disclosure.

Fig. 7 is a schematic configuration diagram of a source gas supply line of a substrate processing apparatus suitably used in the embodiment of the present disclosure.

Fig. 8 is a schematic configuration diagram for explaining a modification 1 of a source gas supply line of a substrate processing apparatus suitably used in the embodiment of the present disclosure.

Fig. 9 is a schematic configuration diagram for explaining a modification 2 of a source gas supply line of a substrate processing apparatus suitably used in the embodiment of the present disclosure.

Detailed Description

< embodiments of the present disclosure >

Hereinafter, an embodiment of the present disclosure will be described with reference to fig. 1 to 7.

(1) Constitution of substrate processing apparatus (heating apparatus)

As shown in fig. 1, the processing furnace 202 is a so-called vertical furnace capable of accommodating substrates in multiple stages in the vertical direction, and includes a heater 207 as a heating device (heating means). The heater 207 has a cylindrical shape, and is supported by a heater base (not shown) as a holding plate and vertically mounted. The heater 207 can also function as an activation mechanism (activation unit) for activating (activating) the gas by heat as described later.

(treatment Chamber)

The reaction tube 203 is provided inside the heater 207 concentrically with the heater 207. The reaction tube 203 is made of, for example, quartz (SiO)₂) Or a heat-resistant material such as silicon carbide (SiC), and is formed into a cylindrical shape with its upper end closed and its lower end open. A header (inlet flange) 209 is provided below the reaction tube 203 in a concentric manner with the reaction tube 203. The manifold 209 is made of metal such as stainless steel (SUS), and is formed in a cylindrical shape with open upper and lower ends. The upper end of the header 209 is configured to be in contact with the lower end of the reaction tube 203, and supports the reaction tube 203. An O-ring 220a as a sealing member is provided between the manifold 209 and the reaction tube 203. The reaction tube 203 is vertically mounted by being supported by the heater base via the manifold 209. The processing vessel (reaction vessel) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in a hollow cylindrical portion which is an inner side of the processing container. The processing chamber 201 is configured to accommodate a plurality of wafers 200 as substrates. The processing container is not limited to the above configuration, and only the reaction tube 203 may be referred to as a processing container.

Nozzles 249a and 249b are provided in the process chamber 201 so as to penetrate the side wall of the manifold 209. The nozzles 249a and 249b are connected to the gas supply pipes 232a and 232b, respectively.

In the gas supply pipes 232a and 232b, Mass Flow Controllers (MFCs) 241a and 241b as flow controllers (flow regulators) and valves 243a and 243b as on-off valves are provided in this order from the upstream side of the gas flow. The gas supply pipes 232a and 232b are connected to gas supply pipes 232c and 232d, respectively, which supply inert gas, on the downstream side of the valves 243a and 243 b. In the gas supply pipes 232c,232d, MFCs 241c,241d and valves 243c,243d are provided in this order from the upstream side of the gas flow.

As shown in fig. 7, a first gas tank 331a, a second gas tank 331b, a first pressure gauge 332a for measuring the pressure of the first gas tank 331a, a second pressure gauge 332b for measuring the pressure of the second gas tank 331b, a first valve 333a for controlling the supply of gas from the first gas tank 331a to the MFC241a via the gas supply pipe 232a, and a second valve 333b for controlling the supply of gas from the second gas tank 331b to the MFC241a via the gas supply pipe 232a are provided on the upstream side of the gas supply pipe 232 a. A first air-operated valve 334a for controlling the supply of gas from the pressure-regulating regulator 335 to the first air tank 331a is provided upstream of the first air tank 331a, and a second air-operated valve 334b for controlling the supply of gas from the pressure-regulating regulator 335 to the second air tank 331b is provided upstream of the second air tank 331 b. The second air-operated valve 334b, the second air tank 331b, the second pressure gauge 332b, and the second valve 333b are provided to act on a small flow rate line for supplying a small flow rate of the raw material gas. The first gas tank 331a and the second gas tank 331b have the same volume, and may have different volumes.

As shown in fig. 2, the nozzle 249a is provided so as to stand upward in the stacking direction of the wafers 200 from the lower portion toward the upper portion of the inner wall of the reaction tube 203 in the space between the inner wall of the reaction tube 203 and the wafers 200. That is, the nozzle 249a is provided along the wafer arrangement region (placement region) in a region laterally surrounding the wafer arrangement region in the horizontal direction and lateral to the wafer arrangement region (placement region) in which the wafers 200 are arranged (placed). That is, the nozzle 249a is provided in a direction perpendicular to the surface (flat surface) of the wafer 200 on the side of the end (peripheral edge) of each wafer 200 loaded into the processing chamber 201. A gas supply hole 250a for supplying gas is provided in a side surface of the nozzle 249 a. The gas supply hole 250a is opened toward the center of the reaction tube 203, and can supply gas toward the wafer 200. The plurality of gas supply holes 250a are provided from the lower portion to the upper portion of the reaction tube 203, have the same opening area, and are provided at the same opening pitch.

The tip end of the gas supply pipe 232b is connected to the nozzle 249 b. The nozzle 249b is provided in the buffer chamber 237 as a gas dispersion space. As shown in fig. 2, the buffer chamber 237 is provided along the deposition direction of the wafer 200 in a portion extending from the lower portion to the upper portion of the inner wall of the reaction tube 203 in a space having an annular shape in plan view between the inner wall of the reaction tube 203 and the wafer 200. That is, the buffer chamber 237 is formed by the buffer structure 300 along the wafer arrangement region in a region horizontally surrounding the wafer arrangement region on the side of the wafer arrangement region. The buffer structure 300 is made of an insulator made of a heat-resistant material such as quartz or SiC, and gas supply ports 302 and 304 for supplying gas are formed in the arc-shaped wall surface of the buffer structure 300. As shown in fig. 2 and 3, the gas supply ports 302 and 304 are opened toward the center of the reaction tube 203 at positions facing the plasma generation regions 224a and 224b between the rod electrodes 269,270 and between the rod electrodes 270 and 271, which will be described later, and can supply gas to the wafer 200. The gas supply ports 302 and 304 are provided in plural numbers from the lower portion to the upper portion of the reaction tube 203, and each have the same opening area and are provided at the same opening pitch.

The nozzle 249b is provided to stand upward along the deposition direction of the wafer 200 from the lower portion toward the upper portion of the inner wall of the reaction tube 203. That is, the nozzles 249b are provided along the wafer arrangement region inside the buffer structure 300, i.e., in a region surrounding the wafer arrangement region in the horizontal direction on the side of the wafer arrangement region where the wafers 200 are arranged. That is, the nozzle 249b is provided on the side of the end of the wafer 200 carried into the processing chamber 201 in a direction perpendicular to the surface of the wafer 200. A gas supply hole 250b for supplying gas is provided in a side surface of the nozzle 249 b. The gas supply holes 250b are opened to a wall surface formed in the radial direction with respect to the arc-shaped wall surface of the buffer structure 300, and can supply gas to the wall surface. Thus, the reaction gas is dispersed in the buffer chamber 237 and does not directly blow to the rod-like electrodes 269 to 271, and generation of particles can be suppressed. The plurality of gas supply holes 250b are provided from the lower portion to the upper portion of the reaction tube 203, similarly to the gas supply holes 250 a.

In this way, in the present embodiment, the gas is transported through the nozzles 249a,249b and the buffer chamber 237, and the nozzles 249a,249b and the buffer chamber 237 are arranged in a vertically long space, that is, a cylindrical space, which is annular in plan view and defined by the inner wall of the side wall of the reaction tube 203 and the end portions of the plurality of wafers 200 arranged in the reaction tube 203. Then, gas is first ejected into the reaction tube 203 from the gas supply holes 250a,250b and the gas supply ports 302,304 opened in the nozzles 249a,249b and the buffer chamber 237, respectively, in the vicinity of the wafer 200. Also, the main flow of the gas in the reaction tube 203 is a direction parallel to the surface of the wafer 200, i.e., a horizontal direction. With this configuration, the gas can be uniformly supplied to each wafer 200, and the film thickness uniformity of the film formed on each wafer 200 can be improved. The gas flowing on the surface of the wafer 200, i.e., the residual gas after the reaction, flows in a direction toward an exhaust port, i.e., an exhaust pipe 231 described later. The flow direction of the residual gas may be appropriately determined depending on the position of the exhaust port, and is not limited to the vertical direction.

A silane source gas (first gas) containing a source material containing a predetermined element, for example, silicon (Si) as a predetermined element is supplied from the gas supply pipe 232a into the processing chamber 201 through the MFC241a, the valve 243a, and the nozzle 249 a.

The raw material gas is a gaseous raw material, and is, for example, a gas obtained by gasifying a raw material in a liquid state at normal temperature and normal pressure, a raw material in a gaseous state at normal temperature and normal pressure, or the like. When a term such as "raw material" is used in the present specification, the term may mean "liquid raw material in a liquid state", the term may mean "raw material gas in a gas state", or both of them.

As the silane source gas, for example, a source gas containing Si and halogen, that is, a halosilane source gas can be used. The halosilane starting material is a silane starting material containing a halogen group. The halogen includes at least 1 selected from the group consisting of chlorine (Cl), fluorine (F), bromine (Br), iodine (I). That is, the halosilane raw material contains at least 1 kind of halo group selected from the group consisting of a chloro group, a fluoro group, a bromo group, and an iodo group. The halosilane starting material may also be referred to as one of the halides.

As the halosilane raw material gas, for example, a raw material gas containing Si and Cl, that is, a chlorosilane raw material gas can be used. As the chlorosilane raw material gas, dichlorosilane (SiH) can be used, for example₂Cl₂For short: DCS) gas.

A nitrogen (N) -containing gas (second gas) as a reaction gas, for example, which is a reactant (reactant) containing an element different from the predetermined element, is supplied from the gas supply pipe 232b into the processing chamber 201 through the MFC241b, the valve 243b, and the nozzle 249 b. As the N-containing gas, for example, a hydrogen nitride-based gas can be used. The hydrogen nitride-based gas may be a substance composed of only 2 elements, i.e., N and H, and functions as a nitriding gas, i.e., an N source. As the hydrogen nitride-based gas, for example, ammonia (NH) can be used₃) A gas.

Nitrogen (N) as an inert gas is supplied from the gas supply pipes 232c,232d₂) The gas is supplied into the processing chamber 201 through MFCs 241c,241d, valves 243c,243d, gas supply pipes 232a,232b, and nozzles 249a,249b, respectively.

The raw material supply system as the first gas supply system is mainly composed of a gas supply pipe 232a, an MFC241a, and a valve 243 a. The reactant supply system (reactant supply system) as the second gas supply system is mainly composed of a gas supply pipe 232b, an MFC241b, and a valve 243 b. The inert gas supply system is mainly constituted by gas supply pipes 232c,232d, MFCs 241c,241d, and valves 243c,243 d. The raw material supply system, the reactant supply system, and the inert gas supply system may be collectively referred to simply as a gas supply system (gas supply unit).

(plasma generating section)

As shown in fig. 2 and 3, 3 rod-like electrodes 269,270,271 each having an elongated structure and made of a conductive material are disposed in the buffer chamber 237 along the deposition direction of the wafers 200 from the lower portion to the upper portion of the reaction tube 203. The rod-like electrodes 269,270,271 are arranged in parallel with the nozzles 249b, respectively. The rod-like electrodes 269,270,271 are each protected from the upper portion up to the lower portion by an electrode protection tube 275. The rod electrodes 269,270,271 are grounded by connecting the rod electrodes 269,271 disposed at both ends to the high-frequency power source 273 via the integrator 272, and connecting the rod electrodes 270 to the ground, which is a reference potential. That is, the rod-like electrodes connected to the high-frequency power source 273 and the grounded rod-like electrodes are alternately arranged, and the rod-like electrode 270 disposed between the rod-like electrodes 269,271 connected to the high-frequency power source 273 is used in common to the rod-like electrode 269,271 as a grounded rod-like electrode. In other words, the grounded rod electrode 270 is disposed so as to be sandwiched between the rod electrodes 269,271 connected to the adjacent high-frequency power source 273, the rod electrode 269 and the rod electrode 270 are paired, and the rod electrode 271 and the rod electrode 270 are configured to be paired in the same manner, thereby generating plasma. That is, the grounded rod electrodes 270 are commonly used for the 2 rod electrodes 269,271 adjacent to the rod electrode 270 and connected to the high-frequency power source 273. Then, by applying a high frequency (RF) power from the high frequency power source 273 to the rod electrodes 269,271, plasma is generated in the plasma generation region 224a between the rod electrodes 269,270 and the plasma generation region 224b between the rod electrodes 270 and 271. The plasma generating portion (plasma generating apparatus) as a plasma source is mainly composed of a rod-like electrode 269,270,271 and an electrode protection tube 275. It is also contemplated that the integrator 272 and the high frequency power source 273 may be incorporated into the plasma source. As described later, the plasma source functions as a plasma excitation portion (activation means) that excites (activates) gas plasma, that is, excites the gas plasma into a plasma state.

The electrode protection tube 275 is configured such that the rod-like electrodes 269,270,271 can be inserted into the buffer chamber 237 in a state isolated from the atmosphere in the buffer chamber 237. O inside the electrode protection tube 275₂If the concentration is O with the outside air (atmosphere)₂If the concentrations are equal, the rod-like electrodes 269,270,271 inserted into the electrode protection tubes 275 are oxidized by the heat of the heater 207. Therefore, N is filled into the electrode protection tube 275₂Inert gas such as gas or N for purging mechanism using inert gas₂By purging the interior of the electrode protection pipe 275 with an inert gas such as a gas, the amount of O in the interior of the electrode protection pipe 275 can be reduced₂Concentration, preventing rod-like electrodes 269,270,271And (4) oxidizing.

An exhaust pipe 231 for exhausting the atmosphere in the processing chamber 201 is provided in the reaction tube 203. The exhaust pipe 231 is connected to a vacuum pump 246 as a vacuum exhaust device via a Pressure sensor 245 as a Pressure detector (Pressure detector) for detecting the Pressure in the processing chamber 201 and an APC (automatic Pressure Controller) valve 244 as an exhaust valve (Pressure regulator). The APC valve 244 is a valve that has been constructed in the following manner: the vacuum exhaust and the vacuum exhaust in the processing chamber 201 can be stopped by opening and closing the valve in a state where the vacuum pump 246 is operated, and the pressure in the processing chamber 201 can be adjusted by adjusting the opening degree of the valve based on the pressure information detected by the pressure sensor 245 in a state where the vacuum pump 246 is operated. The exhaust system is mainly constituted by the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. It is also contemplated that the vacuum pump 246 may be incorporated into the exhaust system. The exhaust pipe 231 is not limited to the case of being provided in the reaction tube 203, and may be provided in the header 209 similarly to the nozzles 249a and 249 b.

A seal cap 219, which is a furnace opening lid body capable of hermetically closing the lower end opening of the header 209, is provided below the header 209. The seal cap 219 is configured to abut against the lower end of the header 209 from the vertically lower side. The seal cap 219 is made of a metal material such as SUS, and is formed in a disk shape. An O-ring 220b as a sealing member is provided on the upper surface of the seal cap 219 to be in contact with the lower end of the manifold 209. A rotation mechanism 267 for rotating the wafer cassette 217 described later is provided on the side of the seal cap 219 opposite to the process chamber 201. The rotary shaft 255 of the rotary mechanism 267 penetrates the seal cap 219 and is connected to the wafer cassette 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the pod 217. The sealing cap 219 is configured to be vertically moved up and down by a cassette lifter 115 as an elevating mechanism vertically provided outside the reaction tube 203. The cassette lifter 115 is configured to be capable of moving the cassette 217 into and out of the processing chamber 201 by lifting and lowering the sealing cap 219. The pod lifter 115 is configured as a transfer device (transfer mechanism) that transfers the pod 217, i.e., the wafer 200, to the inside and outside of the processing chamber 201. Further, a baffle 219s as a furnace opening lid body capable of hermetically closing the lower end opening of the header 209 while the seal cap 219 is lowered by the pod lifter 115 is provided below the header 209. The baffle 219s is made of metal such as SUS, and is formed in a disk shape. An O-ring 220c as a sealing member is provided on the upper surface of the baffle 219s to be in contact with the lower end of the manifold 209. The opening and closing operation (the lifting operation, the rotating operation, and the like) of the shutter 219s is controlled by the shutter opening and closing mechanism 115 s.

(substrate support)

As shown in fig. 1, the wafer cassette 217 serving as a support member is configured to be capable of supporting a plurality of wafers 200 (e.g., 25 to 200 wafers) in a vertical direction in a vertically aligned manner in a horizontal posture with their centers aligned, in multiple stages, that is, at predetermined intervals. The wafer cassette 217 is made of a heat-resistant material such as quartz or SiC. An insulator 218 made of a heat-resistant material such as quartz or SiC is supported in multiple stages at the lower portion of the wafer cassette 217.

As shown in fig. 2, a temperature sensor 263 as a temperature detector is provided inside the reaction tube 203. By adjusting the amount of energization to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature in the processing chamber 201 can be brought to a desired temperature distribution. The temperature sensor 263 is provided along the inner wall of the reaction tube 203 similarly to the nozzles 249a and 249 b.

(control device)

Next, the control device will be described with reference to fig. 4. As shown in fig. 4, the controller 121 as a control Unit (control device) is configured as a computer having a CPU (Central Processing Unit) 121a, a RAM (Random access memory) 121b, a storage device 121c, and an I/O interface 121 d. The RAM121b, the storage device 121c, and the I/O interface 121d are configured to be able to exchange data with the CPU121a via the internal bus 121 e. The controller 121 is connected to an input/output device 122 configured as a touch panel or the like, for example.

The storage device 121c is configured by, for example, a flash memory, an HDD (Hard Disk Drive), or the like. The memory device 121c stores therein a control program for controlling the operation of the substrate processing apparatus, and can read out a process recipe, etc., describing the process, conditions, etc., of the film formation process described later. The process recipe combines each process of various processes (film formation processes) described later so that the controller 121 executes the combined process to obtain a predetermined result, and the combined process functions as a program. Hereinafter, the process recipe, the control program, and the like are also referred to simply as a program. In addition, a process recipe is also referred to simply as a recipe. When the term "process" is used herein, it includes the case of a single process recipe only, the case of a single control process only, and the case of both the cases. The RAM121b is configured as a storage area (work area) for temporarily storing programs, data, and the like read out by the CPU121 a.

The I/O interface 121d is connected to the MFCs 241a to 241d, the valves 243a to 243d, the pressure sensor 245, the APC valve 244, the vacuum pump 246, the heater 207, the temperature sensor 263, the integrator 272, the high-frequency power source 273, the rotating mechanism 267, the pod lifter 115, the shutter opening and closing mechanism 115s, the first gas tank 331a, the second gas tank 331b, the first pressure gauge 332a, the second pressure gauge 332b, the first valve 333a, the second valve 333b, the first pneumatic valve 334a, the second pneumatic valve 334b, the pressure-adjusting regulator 345, and the like.

The CPU121a is configured to read out and execute a control program from the storage device 121c, and read out a recipe and the like from the storage device 121c in response to input of an operation command and the like from the input/output device 122. The CPU121a is further configured to control the rotation mechanism 267, the flow rate adjustment operations of the respective gases by the MFCs 241a to 241d, the opening and closing operations of the valves 243a to 243d, the adjustment operation of the high-frequency power source 273 by impedance monitoring, the opening and closing operation of the APC valve 244, the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment operation of the heater 207 by the temperature sensor 263, the forward and reverse rotation, the rotation angle and rotation speed adjustment operation of the cassette 217 by the rotation mechanism 267, the lifting and lowering operation of the cassette 217 by the cassette lifter 115, the heating operations of the first gas tank 331a and the second gas tank 331b, the opening and closing operation of the first valve 333a by the first pressure gauge 332a, and the opening and closing operation of the second valve 333b by the second pressure gauge 332b, in accordance with the contents of the read recipe, The first and second air-operated valves 334a and 334b are opened and closed, and the pressure adjusting regulator 345 is pressure-adjusted.

The controller 121 may be configured by installing the above-described program stored in an external storage device (for example, a magnetic disk such as a hard disk, an optical disk such as a CD, an optical magnetic disk such as an MO, or a semiconductor memory such as a USB memory) 123 into a computer. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these are also collectively referred to simply as recording media. The present specification, when using the term "recording medium", includes a case of only the storage device 121c alone, includes a case of only the external storage device 123 alone, or includes both of them. Note that the program can be supplied to the computer by using the internet or a dedicated communication method without using the external storage device 123.

(2) Substrate processing procedure

Next, a step of forming a thin film on the wafer 200 as one step of a manufacturing step of a semiconductor device using the substrate processing apparatus 100 will be described with reference to fig. 5 and 6. In the following description, the operations of the respective parts constituting the substrate processing apparatus are controlled by the controller 121.

The following examples are explained below: by supplying DCS gas as a raw material gas and supplying NH excited by plasma as a reaction gas₃An example is one in which a silicon nitride film (SiN film) as a film containing Si and N is formed on the wafer 200 by performing the gas steps non-simultaneously, i.e., asynchronously, a predetermined number of times (1 or more). In addition, for example, a predetermined film may be formed on the wafer 200. In addition, a predetermined pattern may be formed in the wafer 200 or a predetermined film.

For convenience, the process flow of the film formation process shown in fig. 6 may be as follows.

In the present specification, the term "wafer" includes a case of "wafer itself" and a case of "a laminated body of a wafer and a predetermined layer, film, or the like formed on the surface of the wafer". In the present specification, the term "wafer surface" includes a case of "the surface of the wafer itself" and a case of "the surface of a predetermined layer or the like formed on the wafer". In the present specification, the phrase "forming a predetermined layer on a wafer" includes a case where the predetermined layer is directly formed "on the surface of the wafer itself" and a case where the predetermined layer is formed "on a layer or the like formed on the wafer". In the present specification, the term "substrate" is used in the same sense as the term "wafer".

(carry-in step: S1)

After a plurality of wafers 200 are loaded in the wafer cassette 217 (wafer loading), the shutter 219s is moved by the shutter opening/closing mechanism 115s to open the lower end opening of the manifold 209 (shutter opening). Then, as shown in fig. 1, the cassette 217 supporting a plurality of wafers 200 is lifted by the cassette lifter 115 and carried into the processing chamber 201 (cassette mounting). In this state, the seal cap 219 closes the lower end of the manifold 209 via the O-ring 220 b.

(pressure and temperature adjusting step: S2)

Vacuum evacuation (vacuum evacuation) is performed by the vacuum pump 246 so that the inside of the process chamber 201, that is, the space in which the wafer 200 is present, reaches a desired pressure (vacuum degree). At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure information. The vacuum pump 246 is maintained in an operating state at least until the film forming step described later is completed.

Further, the wafer 200 in the processing chamber 201 is heated by the heater 207 to a desired temperature. At this time, the amount of current supplied to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that a desired temperature distribution is achieved in the processing chamber 201. The heating of the inside of the processing chamber 201 by the heater 207 is continued at least until the film formation step described later is completed. However, when the film formation step is performed under a temperature condition of room temperature or lower, the heating in the processing chamber 201 may not be performed by the heater 207. When only the treatment at such a temperature is performed, the heater 207 is not necessary, and the heater 207 may not be provided in the substrate treatment apparatus. In this case, the configuration of the substrate processing apparatus can be simplified.

Next, the rotation of the cassette 217 and the wafer 200 is started by the rotation mechanism 267. The rotation of the cassette 217 and the wafer 200 by the rotating mechanism 267 is continued at least until the film formation step is completed.

(raw material gas supply step: S3, S4)

In step S3, DCS gas is supplied to the wafer 200 in the process chamber 201. The first air-operated valve 334a is opened, the first air tank 331a is filled with DCS gas and heated, and the second air-operated valve 334b is opened, the second air tank 331b is filled with DCS gas and heated. That is, in step S3, when the supply of DCS gas is started, both the first gas tank and the second gas tank are in a state in which DCS gas is filled by a predetermined amount and heated. After a predetermined time has elapsed, the first valve 333a is opened to supply the DCS gas in the first gas tank 331a to the MFC241a, and when the pressure measured by the first pressure gauge 332a reaches a predetermined pressure, the first valve 333a is closed, the second valve 333b is opened to supply the DCS gas in the second gas tank 331b to the MFC241a, and the first pneumatic valve 334a is opened to fill and heat the first gas tank 331a with the DCS gas. After the pressure measured by the second pressure gauge 332b reaches a predetermined pressure, the second valve 333b is closed, the first valve 333a is opened to supply the DCS gas in the first gas tank 331 to the MFC241a, the second air-operated valve 334b is opened, and the second gas tank 331b is filled with the DCS gas and heated. By repeating these operations, DCS gas is supplied to the MFC241a at a large flow rate.

The valve 243a is opened, and DCS gas is flowed into the gas supply pipe 232 a. The flow rate of the DCS gas is adjusted by the MFC241a, and the DCS gas is supplied into the process chamber 201 from the gas supply hole 250a through the nozzle 249a and exhausted through the exhaust pipe 231. At the same time, the valve 243c is opened to flow N into the gas supply pipe 232c₂Gas (es)。N₂The gas is flow-rate-adjusted by the MFC241c, supplied into the process chamber 201 together with the DCS gas, and exhausted through the exhaust pipe 231.

Further, in order to suppress intrusion of DCS gas into the nozzle 249b, the valve 243d is opened to flow N into the gas supply pipe 232d₂A gas. N is a radical of₂The gas is supplied into the processing chamber 201 through the gas supply pipe 232b and the nozzle 249b, and is exhausted through the exhaust pipe 231.

The supply flow rate of the DCS gas controlled by the MFC241a is, for example, 1sccm or more and 6000sccm or less, and preferably, a flow rate in the range of 3000sccm or more and 5000sccm or less. N controlled by MFC241c,241d₂The gas supply flow rate is set to a flow rate in a range of 100sccm or more and 10000sccm or less, for example. The pressure in the processing chamber 201 is, for example, 1Pa or more and 2666Pa or less, and preferably within a range of 665Pa or more and 1333 Pa. The time for which the wafer 200 is exposed to DCS gas is, for example, about 20 seconds per 1 cycle. The time for which the wafer 200 is exposed to DCS gas varies depending on the film thickness.

The temperature of the heater 207 is set to a temperature at which the temperature of the wafer 200 is, for example, 0 ℃ to 700 ℃, preferably room temperature (25 ℃) to 550 ℃, and more preferably 40 ℃ to 500 ℃. As in the present embodiment, by setting the temperature of the wafer 200 to 700 ℃ or lower, further 550 ℃ or lower, further 500 ℃ or lower, the amount of heat applied to the wafer 200 can be reduced, and the thermal history to which the wafer 200 is subjected can be controlled favorably.

By supplying DCS gas to the wafer 200 under the above conditions, a Si-containing layer is formed on the wafer 200 (base film on the surface). The Si-containing layer may contain Cl and H in addition to the Si layer. On the outermost surface of the wafer 200, Si or the like is deposited by physical adsorption of DCS, chemical adsorption of a substance obtained by partial decomposition of DCS, and thermal decomposition of DCS, thereby forming a Si-containing layer. That is, the Si-containing layer may be an adsorption layer (physical adsorption layer or chemical adsorption layer) of DCS, an adsorption layer (physical adsorption layer or chemical adsorption layer) of a substance obtained by decomposing a part of DCS, or a deposition layer (Si layer) of Si.

In shapeAfter the Si-containing layer is formed, the valve 243 is closed to stop the supply of DCS gas into the process chamber 201. At this time, the inside of the processing chamber 201 is evacuated by the vacuum pump 246 while the APC valve 244 is kept open, and the unreacted DCS gas remaining in the processing chamber 201, the DCS gas after the formation of the Si-containing layer, the reaction by-products, and the like are removed from the processing chamber 201 (S4). Further, the supply of N into the processing chamber 201 is maintained in a state where the valves 243c and 243d are opened₂A gas. N is a radical of₂The gas acts as a purge gas. Note that step S4 may be omitted.

As the raw material gas, in addition to DCS gas, tetrakis (dimethylamino) silane (Si [ N (CH) can be suitably used₃)₂]₄For short: 4DMAS gas, tris (dimethylamino) silane (Si [ N (CH) ]₃)₂]₃H, abbreviation: 3DMAS gas, bis (dimethylamino) silane (Si [ N (CH) ]₃)₂]₂H₂For short: BDMAS gas, bis (diethylamino) silane (Si [ N (C) ]₂H₅)₂]₂H₂For short: BDEAS), bis (tert-butylamino) silane (SiH₂[NH(C₄H₉)]₂For short: BTBAS gas, dimethyl amino silane (DMAS) gas, diethyl amino silane (DEAS) gas, dipropyl amino silane (DPAS) gas, diisopropyl amino silane (DIPAS) gas, Butyl Amino Silane (BAS) gas, Hexamethyldisilazane (HMDS) gas, and the like₃Cl, abbreviation: MCS) gas, trichlorosilane (SiHCl)₃For short: TCS) gas, tetrachlorosilane (SiCl)₄For short: STC) gas, hexachlorodisilane (Si)₂Cl₆For short: HCDS) gas, octachloropropylsilane (Si)₃Cl₈For short: OCTS) gas, monosilane (SiH) gas, or the like₄For short: MS) gas, disilane (Si)₂H₆For short: DS) gas, trisilane (Si)₃H₈For short: TS) a halogen-free inorganic silane source gas such as a gas.

As inert gases, other than N₂In addition to the gas, an inert gas such as Ar gas, He gas, Ne gas, Xe gas, or the like can be used.

(reaction gas supplying step: S5, S6)

After the film formation process is completed, NH excited by plasma is supplied as a reaction gas to the wafer 200 in the process chamber 201₃And (S5).

In this step, the valves 243b to 243d are opened and closed in the same manner as the valves 243a,243c, and 243d in step S3. NH (NH)₃The gas is flow-rate-adjusted by the MFC241b and supplied into the buffer chamber 237 through the nozzle 249 b. At this time, high-frequency power is supplied between the rod electrodes 269,270,271. NH supplied to buffer chamber 237₃The gas is excited into a plasma state (converted into plasma and activated) as an active species (NH)₃B) is supplied into the processing chamber 201, and is exhausted through the exhaust pipe 231.

NH controlled by MFC241b₃The gas supply flow rate is, for example, 100sccm or more and 10000sccm or less, and preferably 1000sccm or more and 2000sccm or less. The high-frequency power applied to the rod-like electrode 269,270,271 is, for example, a power in the range of 50W to 600W. The pressure in the processing chamber 201 is, for example, a pressure in the range of 1Pa to 500 Pa. By using plasma, NH can be caused even if the pressure in the processing chamber 201 is set to such a low pressure zone₃And (4) activating the gas. About to pass through to NH₃The time for supplying the active species obtained by plasma excitation of the gas to the wafer 200, that is, the gas supply time (irradiation time), is, for example, in a range of 1 to 180 seconds, preferably 1 to 60 seconds. The other processing conditions are the same as those in S3 described above.

By supplying NH to the wafer 200 under the above conditions₃Gas, the Si-containing layer formed on wafer 200 is plasma nitrided. At this time, NH excited by plasma is passed₃The energy of the gas cuts off the Si-Cl bond and the Si-H bond of the Si-containing layer. Cl and H, whose bonding with Si is cleaved, are detached from the Si-containing layer. Furthermore, due to ClSi in the Si-containing layer that is isoiated and has unbound electrons (dangling bonds) will react with NH₃The N contained in the gas combines to form Si — N bonds. By performing such a reaction, the Si-containing layer is changed (modified) into a layer containing Si and N, that is, a silicon nitride layer (SiN layer).

When the Si-containing layer is modified to be an SiN layer, NH needs to be added₃The gas plasma is excited to supply. This is because NH is supplied even in a non-plasma atmosphere₃In the above temperature range, the gas also has insufficient energy required for nitriding the Si-containing layer, and it is difficult to sufficiently remove Cl and H from the Si-containing layer and sufficiently nitridize the Si-containing layer to increase the Si — N bond.

After the Si-containing layer is converted to the SiN layer, the valve 243b is closed to stop the supply of NH₃A gas. Further, the supply of the high-frequency power between the rod electrodes 269,270,271 is stopped. Then, the NH remaining in the processing chamber 201 is treated in accordance with the same process procedure and process conditions as those in step S4₃The gas and the reaction by-products are exhausted from the processing chamber 201 (S6). Note that step S6 may be omitted.

As nitriding agents, i.e. N-containing gases excited by plasma, other than NH₃As a gas, diazene (N) may be used₂H₂) Gas, hydrazine (N)₂H₄) Gas, N₃H₈Gases, and the like.

As inert gases, other than N₂Besides the gas, for example, various inert gases exemplified in step S4 may be used.

(implementation predetermined times: S7)

By performing the above-described S3, S4, S5, and S6 as 1 cycle in sequence, i.e., not simultaneously, i.e., asynchronously, and performing the cycle a predetermined number of times (n times), i.e., 1 or more times (S7), an SiN film having a predetermined composition and a predetermined film thickness can be formed on the wafer 200. The above cycle is preferably repeated a plurality of times. Namely, it is preferable that: the SiN layer formed in each 1 cycle is less than a desired film thickness, and the above cycle is repeated a plurality of times until the film thickness of the SiN film formed by stacking the SiN layers reaches the desired film thickness.

(atmospheric pressure recovery step: S8)

After the above-described film formation process is completed, N as an inert gas is supplied into the process chamber 201 from the gas supply pipes 232c and 232d, respectively₂The gas is exhausted through the exhaust pipe 231. Thereby, the inside of the processing chamber 201 is purged with the inert gas, and the gas and the like remaining in the processing chamber 201 are removed from the inside of the processing chamber 201 (inert gas purge). Then, the atmosphere in the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (S8).

(carry-out step: S9)

Then, the sealing cap 219 is lowered by the cassette lifter 115 to open the lower end of the manifold 209, and the processed wafer 200 is carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 while being supported by the cassette 217 (cassette unloading) (S9). After unloading the pod, the shutter 219s is moved so that the lower end opening of the manifold 209 is closed by the shutter 219s via the O-ring 220c (closing the shutter). The processed wafer 200 is carried out of the reaction tube 203 and then taken out of the wafer cassette 217 (wafer release). After the wafer is released, an empty wafer cassette 217 may be carried into the processing chamber 201.

(3) Effects according to the present embodiment

According to the present embodiment, 1 or more effects as shown below can be obtained.

(a) According to the present embodiment, by providing a heated gas tank, the pressure of the reactive gas supplied at substantially normal temperature is increased by enclosing and heating the gas, and the supply pressure on the upstream side of the MFC can be increased.

(b) By providing two or more lines in the gas tank on the upstream side of the MFC, the MFC can be made large in flow rate, and can be supplied to the process chamber at a stable large flow rate.

(modification 1)

Next, a modification of the present embodiment will be described with reference to fig. 8. In this modification, only the portions different from the above-described embodiment will be described below, and the description of the same portions will be omitted.

In modification 1, 4 gas tanks having the same volume are provided between the MFC241a and the pressure-regulating regulator 345, and 4 raw material gas supply lines are arranged in parallel.