Substrate processing method, semiconductor device manufacturing method, substrate processing apparatus, and program

Abstract

A substrate processing method according to the present invention comprises: (a) a step for forming a first film on a substrate, the first film having at least either a C-H bond and an Si-C bond or an N-H bond and an Si-N bond; (b) a step for modifying the first film into a second film by subjecting the first film to a heat treatment at a processing temperature that is higher than the processing temperature in step (a); and (c) a step for modifying the second film into a third film by subjecting the second film to plasma processing so that the ratio of the Si-C bond to the C-H bond in the third film is higher than the ratio of the Si-C bond to the C-H bond in the first film, or alternatively, the ratio of the Si-N bond to the N-H bond in the third film is higher than the ratio of the Si-N bond to the N-H bond in the first film.

Description

[Technical Field]

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

[0002] BACKGROUND ART As one step in the manufacturing process of a semiconductor device, a process of forming a film on a substrate is sometimes performed (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-066688 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique that can improve the properties of a film formed on a substrate (for example, Patent Document 1). [Means for solving the problem]

[0005] According to one aspect of the present disclosure, (a) forming a first film containing at least one of a C-H bond and a Si-C bond, and an N-H bond and a Si-N bond on a substrate; (b) performing a heat treatment on the first film at a treatment temperature higher than the treatment temperature in (a) to modify the first film into a second film; (c) performing a plasma treatment on the second film to modify the second film into a third film, and making the ratio of Si-C bonds to C-H bonds in the third film larger than the ratio of Si-C bonds to C-H bonds in the first film, or making the ratio of Si-N bonds to N-H bonds in the third film larger than the ratio of Si-N bonds to N-H bonds in the first film. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to provide a technique that can improve the properties of a film formed on a substrate. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view schematically illustrating an example of the configuration of a substrate processing unit 2000 that is preferably used in one embodiment of the present disclosure. [Figure 2] FIG. 2 is a schematic configuration diagram of the controller 121 of the substrate processing unit 2000 suitably used in one embodiment of the present disclosure, and is a block diagram showing the control system of the controller 121. [Figure 3] FIG. 3 is a side cross-sectional view that schematically illustrates an example of the configuration of a film forming apparatus 300 that is preferably used in one embodiment of the present disclosure. [Figure 4] FIG. 4 is a side cross-sectional view that schematically illustrates an example of the configuration of an annealing apparatus 400 that is preferably used in one embodiment of the present disclosure. [Figure 5] FIG. 5 is a side cross-sectional view schematically illustrating an example of the configuration of a plasma processing apparatus 500 that is preferably used in one embodiment of the present disclosure. [Figure 6] FIG. 6 is a flow diagram illustrating a substrate processing process according to one embodiment of the present disclosure. [Figure 7] FIG. 7 is a diagram showing a processing sequence according to one embodiment of the present disclosure. [Figure 8] FIG. 8 is a diagram showing the measurement results in the example. DETAILED DESCRIPTION OF THE INVENTION

[0008] <One aspect of the present disclosure> Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 7. Note that all drawings used in the following description are schematic, and the dimensional relationships, ratios, etc. of elements shown in the drawings do not necessarily match those of reality. Furthermore, the dimensional relationships, ratios, etc. of elements between multiple drawings do not necessarily match.

[0009] The substrate processing unit 2000 exemplified in this embodiment is used in the manufacturing process of semiconductor devices, and is configured to perform predetermined processing on substrates to be processed. An example of a substrate to be processed is a semiconductor wafer substrate (hereinafter simply referred to as a "wafer") on which a semiconductor integrated circuit device (semiconductor device) is fabricated. In this specification, the term "wafer" may mean "the wafer itself" or "a laminate (assembly) of a wafer and predetermined layers, films, etc. formed on its surface" (i.e., the wafer may be referred to as including predetermined layers, films, etc. formed on the surface). In addition, in this specification, the term "surface of a wafer" may mean "the surface (exposed surface) of the wafer itself" or "the surface of predetermined layers, films, etc. formed on the wafer, i.e., the outermost surface of the wafer as a laminate." In this specification, the term "substrate" is synonymous with the term "wafer." The processes performed on the wafer include, for example, a transfer process, a pressurization (decompression) process, a heating process, a film formation process, a modification process, a diffusion process, and reflow or annealing for carrier activation or planarization after ion implantation.

[0010] (1) Structure of the substrate processing unit First, a configuration example of a substrate processing unit 2000 as a substrate processing apparatus will be described.

[0011] 1, the substrate processing unit 2000 processes wafers 200 as substrates, and is a so-called cluster-type apparatus comprising a film formation apparatus 300, a heat treatment apparatus 400 (also referred to as an annealing apparatus 400), and a plasma treatment apparatus 500. More specifically, the substrate processing unit 2000 comprises an IO stage 2100, an atmospheric transfer chamber 2200, a load lock (L / L) chamber 2300, a vacuum transfer chamber 2400, the film formation apparatus 300, the annealing apparatus 400, and the plasma treatment apparatus 500. In the figure, the X1 direction is the right, the X2 direction is the left, the Y1 direction is the front, and the Y2 direction is the rear.

[0012] An IO stage (load port) 2100 is installed on the front side of the substrate processing unit 100. A plurality of storage containers called FOUPs (Front Open Unified Pods) (hereinafter simply referred to as "pods") 2001 are mounted on the IO stage 2100. The pods 2001 are used as carriers for transporting wafers 200, and are configured to store a plurality of unprocessed wafers 200 or a plurality of processed wafers 200 in a horizontal position inside the pods 200.

[0013] The IO stage 2100 is adjacent to an atmospheric transfer chamber 2200. An atmospheric transfer robot 2220 that transfers the wafer 200 is installed inside the atmospheric transfer chamber 2200. A load lock chamber 2300 is connected to the atmospheric transfer chamber 2200 on the side opposite to the IO stage 2100.

[0014] A vacuum transfer chamber (transfer module: TM) 2400 is connected to the load lock chamber 2300 on the side opposite to the atmospheric transfer chamber 2200.

[0015] The TM 2400 functions as a transfer chamber, which is a transfer space in which the wafer 200 is transferred under negative pressure. A film forming apparatus 300, an annealing apparatus 400, and a plasma processing apparatus 500, which process the wafer 200, are connected to a housing 2410 that constitutes the TM 2400. A vacuum transfer robot 2700 that transfers the wafer 200 under negative pressure is installed in approximately the center of the TM 2400.

[0016] A vacuum transfer robot 2700 installed in the TM 2400 has two arms 2800 and 2900 that can operate independently.

[0017] Gate valves (GV) 1490a, GV 1490b, and GV 1490c are provided between the TM 2400 and the film forming apparatus 300, between the TM 2400 and the annealing apparatus 400, and between the TM 2400 and the plasma processing apparatus 500, respectively. By opening each of the GVs 1490a, 1490b, and 1490c, the vacuum transfer robot 2700 in the TM 2400 can load and unload wafers 200 through substrate loading / unloading ports 350, 450, and 550 provided in the film forming apparatus 300, the annealing apparatus 400, and the plasma processing apparatus 500, respectively (see FIGS. 3, 4, and 5).

[0018] 2, the controller 121, which is a control unit (control means), is configured as a computer including a CPU (Central Processing Unit) 121a, a RAM (Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. The RAM 121b, the storage device 121c, and the I / O port 121d are configured to be able to exchange data with the CPU 121a via an internal bus 121e. An input / output device 122 configured as, for example, a touch panel is connected to the controller 121. An external storage device 123 can also be connected to the controller 121.

[0019] The controller 121 controls the processing operations of the substrate processing unit 2000 including the film forming apparatus 300 , the annealing apparatus 400 , and the plasma processing apparatus 500 .

[0020] The storage device 121c is configured with, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc. Control programs for controlling the operation of the substrate processing apparatus, process recipes describing procedures and conditions for substrate processing (described later), etc., are readably stored in the storage device 121c. The process recipe is a combination of procedures for substrate processing (described later) that are executed by the controller 121 in the substrate processing apparatus to obtain a predetermined result, and functions as a program. Hereinafter, the process recipes, control programs, etc. are collectively referred to simply as programs. The process recipes are also simply referred to as recipes. In this specification, the term "program" may refer to a recipe alone, a control program alone, or both. The RAM 121b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 121a.

[0021] The I / O port 121d is connected to the above-mentioned gate valves 1490a to 1490c, vacuum transfer robot 2700, atmospheric transfer robot 2220, the lifting mechanism 318, APC valves 334, 434, 584, vacuum pumps 335, 435, 585, heaters 313, 413, 513, lamp 416, frequency matching box 574, high-frequency power supply 573, etc.

[0022] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to an input of an operation command from the input / output device 122. The CPU 121a is configured to be able to control the opening and closing operations of the gate valves 1490a to 1490c, the raising and lowering operation of the lifting mechanism 318, the operation of the vacuum transfer robot 2700, the operation of the atmospheric transfer robot 2220, the opening and closing operations of the APC valves 334, 434, 584 and the vacuum pumps 335, 435, 585, the start and stop of the vacuum pumps 335, 435, 585, the temperature adjustment operations of the heaters 313, 413, 513, the temperature adjustment operation of the lamp 416, the power matching operation of the frequency matching box 574, the on / off of the high frequency power supply 573, and the like, in accordance with the contents of the read recipe.

[0023] The controller 121 can be configured by installing the above-mentioned program stored in the external storage device 123 into a computer. The external storage device 123 includes, for example, a magnetic disk such as an HDD, an optical disk such as a CD, a magneto-optical disk such as an MO, and a semiconductor memory such as a USB memory or an SSD. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to simply as recording media. When the term recording media is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both. Note that the program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0024] (2) Configuration of the film deposition equipment Next, we will explain the film formation apparatus 300 used in the above-mentioned substrate processing unit 2000. The film formation apparatus 300 is used when performing film formation processing, which is one step in the manufacturing process of a semiconductor device, and is configured as, for example, a single-wafer type substrate processing apparatus.

[0025] (Processing container) 3, the film forming apparatus 300 includes a processing vessel 302. In the processing vessel 302, a processing chamber 301 for processing the wafer 200 is formed.

[0026] A substrate loading / unloading port 350 adjacent to the GV1490a is provided on the side of the processing vessel 302, and the wafer 200 is configured to move between the processing vessel 302 and the TM 2400 through the substrate loading / unloading port 350. Lift pins 307 are provided on the bottom of the processing vessel 202.

[0027] A susceptor 310 is disposed in the processing chamber 301 as a substrate mounting portion on which the wafer 200 is mounted. A substrate mounting surface 311 on which the wafer 200 is mounted is provided on the upper surface of the susceptor 310. A heater 313 is embedded in the susceptor 310 as a heating mechanism that adjusts the temperature of the wafer 200 on the substrate mounting surface 311. A temperature adjustment unit 315 that adjusts the power supplied to the heater 313 is connected to the heater 313. The temperature adjustment unit 315 is controlled in accordance with instructions from the controller 121. Furthermore, the susceptor 310 is provided with through holes 314, through which the lift pins 307 pass, at positions corresponding to the lift pins 307.

[0028] The susceptor 310 is supported by a shaft 317. The shaft 317 passes through the bottom of the processing vessel 302 and is connected to an elevating mechanism 318 outside the processing vessel 302. The lower end of the shaft 317 is covered with a bellows 319, keeping the inside of the processing chamber 301 airtight.

[0029] (gas inlet) Gas inlet holes 360, 370, and 380 are provided at the top of the processing chamber 301 to supply various gases into the processing chamber 301. The configuration of a gas supply system connected to the gas inlet holes 360, 370, and 380 will be described later.

[0030] (Gas supply system) A raw material (gas) supply pipe 361a, a catalyst supply pipe 371a, and a reactive gas supply pipe 381a are connected to the gas inlet holes 360, 370, and 380, respectively. A raw material (details will be described later) is mainly supplied from the raw material (gas) supply system 361 including the raw material supply pipe 361a. A catalyst (details will be described later) is mainly supplied from the catalyst supply system 371 including the catalyst supply pipe 371a. A reactive gas is mainly supplied from the reactive gas supply system 381 including the reactive gas supply pipe 381a.

[0031] (Raw material supply system) The raw material supply pipe 361a is provided with, in order from the upstream direction, a raw material (gas) supply source 361b, a mass flow controller (MFC) 361c which is a flow rate controller (flow rate control part), and a valve 361d which is an on-off valve.

[0032] The downstream end of a first inert gas supply pipe 362a is connected to the raw material supply pipe 361a downstream of the valve 361d. The first inert gas supply pipe 362a is provided with, in this order from the upstream side, an inert gas supply source 362b, an MFC 362c, and a valve 362d.

[0033] (Catalyst supply system) The catalyst supply pipe 371a is provided with a catalyst supply source 371b, an MFC 371c, and a valve 371d in this order from the upstream direction.

[0034] The downstream end of a second inert gas supply pipe 372a is connected to the catalyst supply pipe 371a downstream of the valve 371d. A second inert gas supply source 372b, an MFC 372c, and a valve 372d are provided in the second inert gas supply pipe 372a in this order from the upstream side.

[0035] (Reaction gas supply system) The reactive gas supply pipe 381a is provided with a reactive gas supply source 381b, an MFC 381c, and a valve 381d in this order from the upstream side.

[0036] The downstream end of a third inert gas supply pipe 382a is connected to the reactive gas supply pipe 381a downstream of the valve 381d. The third inert gas supply pipe 382a is provided with, in order from the upstream side, a third inert gas supply source 382b, an MFC 382c, and a valve 382d.

[0037] In this specification, the raw material (gas), reactive gas, and catalytic gas are also referred to individually or collectively as film-forming gases. Furthermore, the raw material supply system 361, catalyst supply system 371, and reactive gas supply system 381 are also referred to individually or collectively as film-forming gas supply systems.

[0038] (Exhaust system) An exhaust port 345 for exhausting the atmosphere inside the processing chamber 301 is provided on the inner wall side of the processing vessel 302. An exhaust pipe 333 is connected to the outer wall side of the processing vessel 302 so as to communicate with the exhaust port 345. The exhaust pipe 333 is provided with, in this order from the upstream side, an APC (Auto Pressure Controller) valve 334 as a pressure regulator (pressure adjustment unit) and a vacuum pump 335 as a vacuum exhaust device. The exhaust port 355, the exhaust pipe 333, and the APC valve 334 are collectively referred to as an exhaust system.

[0039] (3) Annealing equipment configuration Next, we will explain the annealing apparatus 400 used in the above-mentioned substrate processing unit 2000. The annealing apparatus 400 is used when performing heat treatment (also called annealing treatment), which is one step in the manufacturing process of a semiconductor device, and is configured as, for example, a single-wafer substrate processing apparatus.

[0040] (Processing container) 4, the annealing apparatus 400 includes a processing vessel 402. In the processing vessel 402, a processing chamber 401 for processing the wafer 200 is formed.

[0041] A substrate loading / unloading port 450 adjacent to the GV1490b is provided on the side of the processing vessel 402, and the wafer 200 is configured to move between the processing vessel 402 and the TM2400 through the substrate loading / unloading port 450. Lift pins 407 are provided on the bottom of the processing vessel 402.

[0042] A susceptor 410 is disposed in the processing chamber 401 as a substrate mounting portion on which the wafer 200 is mounted. A substrate mounting surface 411 on which the wafer 200 is mounted is provided on the upper surface of the susceptor 410. A heater 413 is embedded in the susceptor 410 as a heating mechanism for adjusting the temperature of the wafer 200 on the substrate mounting surface 411. A heater control unit 420 for controlling the temperature of the heater 413 is connected to the heater 413. The heater control unit 420 controls the on / off of the heater 413 based on instructions from the controller 121. Furthermore, the susceptor 410 is provided with through holes 314 through which the lift pins 307 pass, at positions corresponding to the lift pins 307.

[0043] The susceptor 410 is supported by a shaft 417. The shaft 417 penetrates the bottom of the processing vessel 402 and is connected to an elevating mechanism 418 outside the processing vessel 402. The lower end of the shaft 417 is covered with a bellows 419, keeping the inside of the processing chamber 401 airtight.

[0044] (lamp) A lamp house 460 is provided on the ceiling of the processing chamber 402 at a position facing the surface of the wafer 200. The lamp house 460 is provided with a plurality of lamps 461 as a heating mechanism.

[0045] The lamp 461 is connected to a lamp control unit 463 via a wire 462. The lamp control unit 463 controls the on / off of the lamp 461 based on instructions from the controller 121.

[0046] A window 464 is provided on the ceiling of the processing vessel 402 at a position facing the lamp 461. The window 464 is vacuum-resistant and made of a material such as quartz that does not block the heat irradiated from the lamp 461.

[0047] (gas inlet) A gas inlet 440 for supplying an inert gas into the processing chamber 401 is provided at the top of the processing chamber 401 .

[0048] (inert gas supply system) An inert gas supply pipe 441a is connected to the gas introduction hole 440. An inert gas (described in detail later) is supplied from an inert gas supply system 441 including the inert gas supply pipe 441a. An inert gas supply source 441b, an MFC 441c, and a valve 441d are provided in the inert gas supply pipe 441a in this order from the upstream direction.

[0049] (Exhaust system) An exhaust port 445 for exhausting the atmosphere inside the processing chamber 401 is provided on the inner wall side of the processing vessel 402. An exhaust pipe 433 is connected to the outer wall side of the processing vessel 402 so as to communicate with the exhaust port 445. The exhaust pipe 433 is provided with, in this order from the upstream side, an APC valve 434 as a pressure regulator (pressure adjustment unit) and a vacuum pump 435 as a vacuum exhaust device. The exhaust port 455, the exhaust pipe 433, and the APC valve 434 are collectively referred to as an exhaust system.

[0050] (4) Configuration of plasma processing equipment Next, a plasma processing apparatus 500 used in the above-mentioned substrate processing unit 2000 will be described. The plasma processing apparatus 500 is used when performing a film formation process, which is one step in the manufacturing process of a semiconductor device, and is configured as, for example, a single-wafer substrate processing apparatus. Figure 5 is a schematic diagram of the plasma processing apparatus 500 according to this embodiment.

[0051] (Processing chamber) 5, the plasma processing apparatus 500 includes a processing furnace 502 that accommodates wafers 200 and performs plasma processing. The processing furnace 502 includes a processing container 503 that forms a processing chamber 501. The processing container 503 includes an upper container 530 and a lower container 531. The processing chamber 501 is formed by the upper container 530 covering the lower container 531.

[0052] A substrate loading / unloading port 550 adjacent to the GV1490c is provided on the lower sidewall of the lower vessel 531, and the wafer 200 is configured to move between the TM2400 and the substrate loading / unloading port 550. Lift pins 507 are provided on the bottom of the processing vessel 503.

[0053] The processing chamber 501 has a plasma generation space 501a around which a resonant coil 522 is provided, and a substrate processing space 501b that communicates with the plasma generation space 501a and processes the wafer 200. The plasma generation space 501a is a space where plasma is generated, and refers to the space in the processing chamber 501 that is above the lower end of the resonant coil 522 and below the upper end of the resonant coil 522. The substrate processing space 501b is a space where the wafer 200 is processed using plasma, and refers to the space below the lower end of the resonant coil 522.

[0054] A susceptor 510 serving as a substrate mounting portion for mounting the wafer 200 is disposed within the processing chamber 501. A substrate mounting surface 511 on which the wafer 200 is mounted is provided on the upper surface of the susceptor 510.

[0055] A heater 513 is embedded inside the susceptor 510 as a heating mechanism for adjusting the temperature of the wafer 200 on the substrate mounting surface 511. By supplying power to the heater 513 via a heater power adjustment mechanism 576, the surface of the wafer 200 can be heated to a predetermined temperature within a range of, for example, 25°C to 1000°C.

[0056] The susceptor 510 is electrically insulated from the lower chamber 531. An impedance adjusting electrode 515 is provided inside the susceptor 510. The impedance adjusting electrode 515 is grounded via an impedance variable mechanism 577 serving as an impedance adjuster. The potential (bias voltage) of the wafer 200 during plasma processing can be controlled via the impedance adjusting electrode 515 and the susceptor 510.

[0057] A susceptor lifting mechanism 568 that raises and lowers the susceptor is provided below the susceptor 510. The susceptor 510 has a through-hole 514. The bottom surface of the lower vessel 531 is provided with lift pins 507 as supports that support the wafer 200. When the susceptor 510 is lowered by the susceptor lifting mechanism 568, the lift pins 507 pass through the through-holes 514 without coming into contact with the susceptor 510. This makes it possible to hold the wafer 200 from below.

[0058] A gas supply head 536 is provided above the processing chamber 501, i.e., on the top of the upper vessel 530. The gas supply head 536 includes a lid 533, a gas inlet hole 534, a buffer chamber 537, an opening 538, a shielding plate 540, and a gas outlet 539, and is configured to supply gas into the processing chamber 501.

[0059] (Gas supply system) A hydrogen (H)-containing gas supply pipe 561a is connected to the gas introduction hole 543. A hydrogen-containing gas (details will be described later) is mainly supplied from a H-containing gas supply system (described later).

[0060] The H-containing gas supply pipe 561a is provided with, in this order from the upstream side, an H-containing gas supply source 561b, an MFC 561c, and a valve 561d which is an on-off valve.

[0061] A downstream end of a fourth inert gas supply pipe 562a is connected to the H-containing gas supply pipe 561a downstream of the valve 561d. The fourth inert gas supply pipe 562a is provided with, in this order from the upstream side, an inert gas supply source 562b, an MFC 562c, and a valve 562d.

[0062] (Exhaust system) An exhaust port 595 for exhausting the atmosphere inside the processing chamber 501 is provided on the side of the inner wall of the lower container 531. An exhaust pipe 583 is connected to the side of the outer wall of the lower container 531 so as to communicate with the exhaust port 595. An APC valve 584 serving as a pressure regulator (pressure adjustment unit) and a vacuum pump 585 serving as a vacuum exhaust device are provided on the exhaust pipe 583, in this order from the upstream side. The exhaust port 595, the exhaust pipe 583, and the APC valve 584 are collectively referred to as an exhaust system.

[0063] A spiral resonant coil 522 is provided on the outer periphery of the processing chamber 501, i.e., on the outside of the sidewall of the upper vessel 530, so as to surround the processing chamber 501. An RF (Radio Frequency) sensor 572, a high-frequency power supply 573, and a frequency matching box 574 (frequency control unit) are connected to the resonant coil 522. A shielding plate 223 is provided on the outer periphery of the resonant coil 212.

[0064] (5) Substrate processing process 6 and 7, an example of a substrate processing sequence will be described, in which, as one step in a semiconductor device manufacturing process, a first film is formed on a wafer 200 as a substrate in a film forming apparatus 300, the first film is subjected to a heat treatment (annealing treatment) in an annealing apparatus 400 to modify the first film into a second film, and the second film is subjected to a plasma treatment in a plasma processing apparatus 500 to modify the second film into a third film. In the following description, the operation of each component constituting the substrate processing unit 2000 is controlled by a controller 121.

[0065] The substrate processing sequence in this embodiment is as follows: Step a) of forming a first film containing at least one of a C-H bond and a Si-C bond, and an N-H bond and a Si-N bond on a wafer 200; Step b: modifying the first film into a second film by performing a heat treatment on the first film at a treatment temperature higher than the treatment temperature in step a; and step c) performing a plasma treatment on the second film to modify the second film into a third film, and making the ratio of Si-C bonds to C-H bonds in the third film greater than the ratio of Si-C bonds to C-H bonds in the first film, or making the ratio of Si-N bonds to N-H bonds in the third film greater than the ratio of Si-N bonds to N-H bonds in the first film.

[0066] In this embodiment, an example will be described in which, in step a, a process of supplying a raw material containing at least C-H bonds and Si-C bonds and a catalyst to the wafer 200 and a process of supplying an oxidizing agent and a catalyst as a reactive gas to the wafer 200 are alternately performed to form a silicon oxycarbide film (SiOC film) as a first film containing C-H bonds and Si-C bonds on the wafer 200. Also, in this embodiment, an example will be described in which, in step c, hydrogen (H) gas is excited into a plasma state and supplied to the second film.

[0067] SiOC films are low-k films with a low dielectric constant and high hydrogen fluoride (HF) etching resistance (hereinafter referred to as HF resistance), and are therefore widely used as spacer films, for example. On the other hand, SiOC films may be subjected to oxidation treatments such as oxygen (O2) plasma ashing after deposition as part of the manufacturing process of semiconductor devices. The ashing treatment (oxidation treatment) can deteriorate the HF resistance of the SiOC film, resulting in loss of its function as a spacer film. This embodiment describes a SiOC film that maintains both a low dielectric constant and high HF resistance even when ashing is performed after deposition. Hereinafter, the HF resistance of a film after ashing may be referred to as ashing resistance.

[0068] In this specification, the substrate processing sequence described above may be expressed as follows for convenience: Similar notations will be used in the following descriptions of modified examples and other aspects.

[0069] (raw material + catalyst → oxidant + catalyst) × n → heat treatment (annealing treatment) → plasma-excited H gas → SiOC film

[0070] (Wafer transport into film forming apparatus 300: S300) The atmospheric transfer robot 2220 removes the wafer 200 to be processed from the pod 2001 on the IO stage 2100. With the susceptor 310 lowered to a predetermined transfer position, the GV 1490a is opened, and the wafer 200 is transferred from the TM 2400 into the processing chamber 301 by the vacuum transfer robot 2700. The wafer 200 transferred into the processing chamber 301 is supported in a horizontal position on lift pins 307 protruding upward from the substrate mounting surface 311 of the susceptor 310. After the wafer 200 has been transferred into the processing vessel 302, the vacuum transfer robot 2700 is removed from the processing chamber 301, and the GV 1490a is closed. The susceptor 310 is then raised to a predetermined processing position, and the wafer 200 to be processed is transferred from the lift pins 307 onto the susceptor 310.

[0071] (Pressure and temperature regulation: S301) Next, the processing chamber 301 is evacuated by the vacuum pump 335 to a desired processing pressure. The pressure inside the processing chamber 301 is measured by a pressure sensor, and the APC valve 334 is feedback-controlled based on this measured pressure information. The wafers 200 are also heated by the heater 313 to a desired processing temperature. Once the processing chamber 301 has reached the desired processing pressure and the temperature of the wafers 200 has reached and stabilized at the desired processing temperature, the film formation process described below begins.

[0072] (Film formation process: S302) In this step (step a), the following steps a1 and a2 are executed.

[0073] [Step a1] In step a1, a raw material (raw material gas) and a catalyst (catalytic gas) are supplied to the wafer 200 in the processing chamber 301 as a film forming agent.

[0074] Specifically, valves 361d and 371d are opened to allow the raw material and catalyst to flow into the raw material supply pipe 361a and the catalyst supply pipe 371a, respectively. The raw material and catalyst have their flow rates adjusted by MFCs 361d and 371d, are supplied into the processing chamber 301 via the buffer chamber 343, are mixed in the processing chamber 301, and are exhausted from the exhaust port 345. At this time, the raw material and catalyst are supplied to the wafer 200 from above the wafer 200 (raw material + catalyst supply). At this time, valves 362d, 372d, and 382d are opened to supply an inert gas into the processing chamber 301 via the raw material supply pipe 361a, the catalyst supply pipe 371a, and the reactive gas supply pipe 381a, respectively. Note that the supply of an inert gas may not be performed in some of the methods described below.

[0075] The processing conditions for supplying the raw material and catalyst in this step (step a1) are as follows: Treatment temperature: room temperature (25°C) to 120°C, preferably room temperature to 90°C Processing pressure: 133~1333Pa Raw material supply flow rate: 0.001~2slm Catalyst supply flow rate: 0.001~2slm Inert gas supply flow rate (per gas supply pipe): 0 to 20 slm Each gas supply time: 1 to 60 seconds is exemplified.

[0076] In this specification, when a numerical range such as "25 to 120°C" is expressed, it means that the lower limit and the upper limit are included in the range. Therefore, for example, "450 to 750°C" means "450°C or higher and 750°C or lower." The same applies to other numerical ranges. In this specification, the processing temperature means the temperature of the wafer 200 or the temperature inside the processing chamber 301, and the processing pressure means the pressure inside the processing chamber 301. In addition, when the supply flow rate includes 0 slm, 0 slm means that the gas is not supplied. This also applies to the following description.

[0077] Under the above conditions, a raw material, for example, a chlorosilane-based gas containing a C-H bond and a Si-C bond, is supplied to the wafer 200, whereby a silicon (Si)-containing layer containing C, H, and Cl is formed as a first layer on the outermost surface of the wafer 200. The Si-containing layer containing C, H, and Cl is a layer containing C-H bonds and Si-C bonds. In this specification, the Si-containing layer containing C, H, and Cl is also referred to as a Si-containing layer containing C or a SiC layer for convenience.

[0078] By supplying the raw material to the wafer 200 under the above-mentioned conditions, it becomes possible to retain at least a portion of the Si-C bonds and C-H bonds contained in the raw material without breaking them and to incorporate (remain) them in the first layer as they are.

[0079] The first layer includes not only a continuous layer made of Si and containing C, H, and Cl, but also discontinuous layers and thin Si films containing C, H, and Cl formed by overlapping these. The Si that makes up the Si layer containing C, H, and Cl includes Si whose bonds with C and Cl are completely broken as well as Si whose bonds with C and Cl are completely broken.

[0080] In this step, by supplying a catalyst together with the raw materials, the above-mentioned reaction can be carried out in a non-plasma atmosphere under the above-mentioned low temperature conditions.

[0081] Furthermore, by forming the first layer in a non-plasma atmosphere and under the above-mentioned low temperature conditions, it is possible to prevent the raw material from thermally decomposing (vapor phase decomposition), i.e., from self-decomposing, in the processing chamber 301. This makes it possible to adsorb the raw material onto the wafer 200 and form an adsorption layer of the raw material.

[0082] After the first layer is formed, the valves 361d and 371d are closed to stop the supply of raw materials and catalyst into the processing chamber 301. Then, the processing chamber 301 is evacuated to remove gases and the like remaining in the processing chamber 301. At this time, the valves 362d, 372d, and 382d are left open to continue the supply of inert gas into the processing chamber 301. The inert gas acts as a purge gas, thereby purging the processing chamber 301.

[0083] As a raw material, for example, a silane-based gas containing Si as the main element constituting the film formed on the wafer 200 can be used. As the silane-based gas, for example, a gas containing Si and a halogen, i.e., a halosilane-based gas can be used. Halogen includes chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. As the halosilane-based gas, for example, the above-mentioned chlorosilane-based gas containing Si and Cl can be used.

[0084] As a raw material, for example, alkylenechlorosilane gases such as bis(trichlorosilyl)methane ((SiCl3)2CH2, abbreviated as BTCSM) gas and 1,2-bis(trichlorosilyl)ethane ((SiCl3)2C2H4, abbreviated as BTCSE) gas can be used.

[0085] As a raw material, for example, alkylchlorosilane gases such as 1,1,2,2-tetrachloro-1,2-dimethyldisilane ((CH3)2Si2Cl4, abbreviated as TCDMDS) gas and 1,2-dichloro-1,1,2,2-tetramethyldisilane ((CH3)4Si2Cl2, abbreviated as DCTMDS) gas can be used.

[0086] As a raw material, a gas containing a ring structure composed of Si and C and a halogen, such as 1,1,3,3-tetrachloro-1,3-disilacyclobutane (C2H4Cl4Si2, abbreviated as TCDSCB) gas, can be used.

[0087] As described above, it is preferable to use a gas containing a C—H bond and a Si—C bond as the raw material, and one or more of these can be used as the raw material.

[0088] As the catalyst, for example, an amine-based gas containing carbon (C), nitrogen (N), and H can be used. Examples of the amine-based gas include pyridine (Py) gas, aminopyridine (C5H6N2) gas, picoline (C6H7N) gas, lutidine (C7H9N) gas, piperazine (C4H 10 N2 gas, piperidine (CH 11 Examples of the catalyst that can be used include cyclic amine gases such as triethylamine ((C2H5)3N, abbreviated as TEA) gas and diethylamine ((C2H5)2NH, abbreviated as DEA) gas, and chain amine gases such as triethylamine ((C2H5)3N, abbreviated as TEA) gas and diethylamine ((C2H5)2NH, abbreviated as DEA) gas. In addition to these, ammonia (NH3) gas or the like can also be used as the catalyst. One or more of these can be used as the catalyst. This also applies to step a2 described below.

[0089] As described above, it is preferable to use a gas containing Si and H and at least one of C and N as the film-forming gas (raw material, catalyst).

[0090] The inert gas may be, for example, nitrogen (N2) gas or a rare gas such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, or xenon (Xe) gas. One or more of these may be used as the inert gas. This also applies to each step described below.

[0091] [Step a2] After step a1 is completed, an oxidizing agent (oxidizing gas) and a catalyst (catalytic gas) are supplied to the wafers 200 in the processing chamber 201, that is, to the Si-containing layer formed on the wafers 200.

[0092] Specifically, valves 381d and 371d are opened to allow the oxidant and catalyst to flow into the reactive gas supply pipe 381a and the catalyst supply pipe 371a, respectively. The oxidant and catalyst have their flow rates adjusted by MFCs 381d and 371d, are supplied into the processing chamber 301 via the buffer chamber 343, are mixed in the processing chamber 301, and are exhausted from the exhaust port 345. At this time, the oxidant and catalyst are supplied to the wafer 200 from above the wafer 200 (oxidant + catalyst supply). At this time, valves 362d, 372d, and 382d are kept open to maintain the supply of inert gas into the processing chamber 301.

[0093] The processing conditions for supplying the oxidant and catalyst in this step (step a2) are as follows: Treatment temperature: room temperature (25°C) to 120°C, preferably room temperature to 100°C Oxidant supply flow rate: 0.001 to 2 slm Catalyst supply flow rate: 0.001~2slm The other processing conditions are the same as the processing conditions in step a1.

[0094] By supplying the oxidizing agent to the wafer 200 under the above-described conditions, at least a portion of the first layer formed on the wafer 200 in step a1 is oxidized (modified). As a result, a silicon oxycarbide layer (SiOC layer) is formed on the outermost surface of the wafer 200 as a second layer formed by oxidizing the first layer. When the second layer is formed, impurities such as Cl contained in the first layer are converted into a gaseous substance containing at least Cl during the modification reaction, and are exhausted from the processing chamber 301. As a result, the second layer contains fewer impurities such as Cl than the first layer formed in step a1.

[0095] By supplying the oxidizing agent to the wafer 200 under the above-mentioned processing conditions, it becomes possible to retain at least a portion of the Si-C bonds and C-H bonds contained in the first layer without breaking them and to incorporate them (remain) in the second layer. By supplying the oxidizing agent to the wafer 200 under the above-mentioned processing conditions, the second layer formed becomes a layer containing moisture, i.e., OH groups.

[0096] In this step, as in step a1, by supplying a catalyst together with an oxidizing agent, it becomes possible to carry out the above-mentioned reaction in a non-plasma atmosphere and under low temperature conditions as described below.

[0097] After the second layer is formed, the valves 381d and 371d are closed to stop the supply of the oxidizing agent into the processing chamber 301. Then, the processing chamber 301 is evacuated to remove gases and the like remaining in the processing chamber 301. At this time, the gases and the like remaining in the processing chamber 301 are removed (purged) from the processing chamber 301 by the same processing procedure as the purging in step a1.

[0098] Examples of the oxidizing agent include an oxygen (O)-containing gas and an oxygen (O) and hydrogen (H)-containing gas. Examples of the O-containing gas include oxygen (O) gas, ozone (O) gas, nitrous oxide (NO) gas, nitric oxide (NO) gas, nitrogen dioxide (NO) gas, carbon monoxide (CO) gas, and carbon dioxide (CO) gas. Examples of the O- and H-containing gas include water vapor (HO gas), hydrogen peroxide (HO), hydrogen (H) gas + oxygen (O) gas, and H gas + ozone (O) gas. Note that the O- and H-containing gas is also an O-containing gas. In addition to these, a cleaning solution, such as a cleaning solution containing ammonia water, hydrogen peroxide water, and pure water, may also be used as the oxidizing agent. That is, oxidation may be performed by APM cleaning. In this case, oxidation can be performed by exposing the wafer 200 to the cleaning solution. As described above, the oxidizing agent may be a gaseous substance or a liquid substance. The oxidizing agent may also be a liquid substance such as a mist-like substance. One or more of these may be used as the oxidizing agent.

[0099] [Perform the cycle a specified number of times] By performing the above-described steps a1 and a2 asynchronously, i.e., without synchronization, a predetermined number of times (n times, where n is an integer equal to or greater than 1), a SiOC film containing Si, O, and C with a predetermined thickness can be formed as the first film on the wafer 200. The above-described cycle is preferably repeated multiple times. That is, it is preferable to make the thickness of the second layer (SiOC layer) formed per cycle thinner than the desired thickness, and to repeat the above-described cycle multiple times until the thickness of the SiOC film as the first film formed by stacking the second layer reaches the desired thickness.

[0100] By carrying out step a under the above-mentioned conditions, it becomes possible to retain at least a portion of the C—H bonds and Si—C bonds contained in the raw material without breaking them and to incorporate (remain) them in the first film (SiOC film).

[0101] Furthermore, by performing step a under the above-described conditions, the first film (SiOC film) formed on the wafer 200 becomes a film containing moisture, ie, OH groups, on its surface.

[0102] (After-purge and atmospheric pressure recovery: S303) After the process of forming the first film (SiOC film) of a desired thickness on the wafer 200 is completed, the process chamber 301 is evacuated to remove gases and other substances remaining in the process chamber 301. Then, using the same process procedures and conditions as the above-described purging, gaseous substances and other substances remaining in the process chamber 301 are removed from the process chamber 301 (after-purging). Thereafter, the atmosphere in the process chamber 301 is replaced with a purge gas, and the pressure in the process chamber 301 is returned to normal pressure (return to atmospheric pressure).

[0103] (Wafer transported out of film forming apparatus 300: S304) Thereafter, the susceptor 310 is lowered to a predetermined transfer position, and the wafer 200 is transferred from the susceptor 310 onto the lift pins 307. Thereafter, the GV 1490a is opened, and the processed wafer 200 is transferred out of the processing chamber 302 (TM2400) by the vacuum transfer robot 2700.

[0104] (Wafer is carried into the annealing device 400: S400) With the susceptor 410 lowered to a predetermined transfer position, the GV1490b is opened, and the wafer 200 is transferred from the TM2400 into the processing chamber 401 by the vacuum transfer robot 2700. The wafer 200 transferred into the processing chamber 401 is supported in a horizontal position on lift pins 407 protruding upward from the substrate mounting surface 411 of the susceptor 410. After the wafer 200 has been transferred into the processing chamber 401, the vacuum transfer robot 2700 is removed from the processing chamber 401, and the GV1490b is closed. Thereafter, the susceptor 410 is raised to a predetermined processing position, and the wafer 200 to be processed is transferred from the lift pins 407 onto the susceptor 410.

[0105] (Pressure and temperature regulation: S401) Subsequently, similarly to S301, the pressure is controlled by the vacuum pump 435 and the APC valve 434, and the heating is controlled by the heater 413 and the lamp 461.

[0106] (Heat treatment (annealing): S402) The wafers 200 in the processing chamber 401 are heated, and a heat treatment is performed on the first film (SiOC film) formed on the wafers 200. At this time, the valve 441d is opened to allow an inert gas to flow into the inert gas supply pipe 441a. The inert gas has a flow rate adjusted by the MFC 441c, is supplied into the processing chamber 401, and is exhausted from the exhaust port 445. At this time, the inert gas is supplied to the wafers 200 from above the wafers 200.

[0107] The processing conditions in this step (step b) are as follows: Treatment temperature: 200 to 1000°C, preferably 500 to 700°C Processing pressure: 133~1333Pa Inert gas supply flow rate: 0.001 to 20 slm Inert gas supply time: 1 to 120 minutes, preferably 1 to 60 minutes is exemplified.

[0108] By performing a heat treatment on the first film formed on the wafer 200 under the above-described processing conditions, moisture contained in the first film can be desorbed from the first film. More specifically, by setting the processing temperature in this step to a relatively high processing temperature, for example, higher than the processing temperature in the above-described film formation process (step a), moisture (OH groups present on the surface of the first film) and impurities such as Cl contained in the first film can be efficiently desorbed. In this way, a second film is formed on the wafer 200, resulting from the desorption of moisture and impurities such as Cl from the first film. By removing the moisture and impurities from the first film under the above-described processing conditions, it is possible to make the second film a low-k film having a lower dielectric constant than the first film, or to maintain the second film as a low-k film having a low dielectric constant similar to that of the first film.

[0109] By performing a heat treatment on the first film formed on the wafer 200 under the above-mentioned processing conditions, it becomes possible to retain at least a portion of the Si-C bonds and C-H bonds contained in the first film without breaking them and to incorporate (remain) them in the second film. Also, under the above-mentioned processing conditions, at least a portion of Si, O, and C contained in the first film remains in the second film without being removed.

[0110] (After-purge and atmospheric pressure recovery: S403) After the heat treatment is completed, the processing chamber 401 is evacuated to remove gases and other substances remaining in the processing chamber 401. Then, using the same processing procedures and conditions as the above-described purging, gaseous substances and other substances remaining in the processing chamber 401 are removed from the processing chamber 401 (after-purging). Thereafter, the atmosphere in the processing chamber 401 is replaced with a purge gas, and the pressure in the processing chamber 401 is returned to normal pressure (return to atmospheric pressure).

[0111] (Wafer transported out of annealing apparatus 400: S404) Thereafter, the susceptor 410 is lowered to a predetermined transfer position, and the wafer 200 is transferred from the susceptor 410 onto the lift pins 407. Thereafter, the GV 1490b is opened, and the processed wafer 200 is transferred out of the processing chamber 402 (TM2400) by the vacuum transfer robot 2700.

[0112] (Wafer is carried into plasma processing apparatus 500: S500) With the susceptor 510 lowered to a predetermined transfer position, the GV 1490c is opened, and the wafer 200 is transferred from the TM 2400 into the processing chamber 501 by the vacuum transfer robot 2700. The wafer 200 transferred into the processing chamber 501 is supported in a horizontal position on lift pins 507 protruding upward from the substrate mounting surface 511 of the susceptor 510. After the wafer 200 has been transferred into the processing chamber 501, the vacuum transfer robot 2700 is removed from the processing chamber 501, and the GV 1490c is closed. Thereafter, the susceptor 510 is raised to a predetermined processing position, and the wafer 200 to be processed is transferred from the lift pins 507 onto the susceptor 510.

[0113] (Pressure and temperature adjustment: S501) Next, similarly to steps S301 and S401, the pressure is controlled by the vacuum pump 585 and the APC valve 584, and heating is performed by the heater 513. When the interior of the processing chamber 501 reaches a desired processing pressure and the temperature of the wafer 200 reaches and stabilizes at a desired processing temperature, plasma processing, which will be described later, is started.

[0114] (Plasma treatment: S502) H gas is excited into a plasma state and supplied to the wafer 200 in the processing chamber 501, that is, to the second film formed on the wafer 200.

[0115] Specifically, the valve 561d is opened to allow H gas to flow into the gas supply pipe 561a. The H gas has a flow rate adjusted by the MFC 561c, is supplied into the processing chamber 501 via the buffer chamber 537, and is exhausted from the exhaust port 595. At this time, the H gas is supplied to the wafer 200 from above the wafer 200 (H gas supply). At this time, the valve 562d may be opened to supply an inert gas into the processing chamber 501 via the buffer chamber 537.

[0116] At this time, radio frequency (RF) power is applied to the resonant coil 522 from the radio frequency power supply 573. As a result, induction plasma having a doughnut shape in a plan view is excited at the upper and lower ground points and at height positions corresponding to the electrical midpoint of the resonant coil 522 in the plasma generation space 501a. The excitation of the induction plasma activates the H gas, and excited H atoms (H * ), ionized H atoms, and other reactive species are generated. * denotes radicals. This also applies to the following explanation. Then, the second film formed on the wafer 200 in step b is subjected to plasma processing mainly by these reactive species.

[0117] The processing conditions in this step (step c) are as follows: Treatment temperature: 100 to 850°C, preferably 450 to 600°C Treatment pressure: 667 to 26664 Pa, preferably 6666 to 13332 Pa H gas supply flow rate: 0.1 to 10 slm, preferably 0.15 to 0.5 slm H gas supply time: 5 to 600 seconds, preferably 30 to 300 seconds RF power: 100-5000W, preferably 500-3500W RF frequency: 800kHz~50MHz is exemplified.

[0118] By performing a plasma treatment on the second film formed on the wafer 200 under the above-described treatment conditions, the second film can be modified into a third film. Specifically, at least some of the C-H bonds contained in the second film can be broken while the Si-C bonds contained in the second film are maintained intact in the third film. More specifically, for example, by setting the treatment temperature in this step higher than the treatment temperature in the above-described film formation treatment (step a), at least some of the C-H bonds contained in the second film can be broken while the Si-C bonds contained in the second film are maintained intact in the third film. On the other hand, even if the treatment temperature in this step is set to a relatively low temperature, for example, lower than the treatment temperature in the above-described heat treatment (step b), at least some of the C-H bonds contained in the second film can be broken while the Si-C bonds contained in the second film are maintained intact in the third film.

[0119] Then, the C bond in the C-H bond resulting from the cleavage of H bonds bonds with Si present in the third film, thereby making the ratio of Si-C bonds to C-H bonds in the third film greater than the ratio of Si-C bonds to C-H bonds in the first film. Furthermore, the ratio of Si-C bonds in the third film can be made greater than the ratio of Si-C bonds in the first film, and the ratio of C-H bonds in the third film can be made smaller than the ratio of C-H bonds in the first film. In this way, at least the surface of the third film can be densified. By adjusting the ratio of Si-C bonds to C-H bonds in the third film in this way, the ashing resistance of the third film (SiOC film) can be improved. Furthermore, by densifying at least the surface of the third film, the ashing resistance of the third film (SiOC film) can be improved. By performing a plasma treatment on the second film under the above-described treatment conditions, the modified third film can be made into a film with good ashing resistance while maintaining a low dielectric constant.

[0120] Moreover, under the above-mentioned processing conditions, at least a portion of Si, O, and C contained in the second film is not removed but remains in the third film.

[0121] If the processing temperature is less than 100°C, the ashing resistance of the third film (SiOC film) formed on the wafer 200 may not be good. By setting the processing temperature to 100°C or higher, it is possible to form a third film with excellent ashing resistance on the wafer 200. By setting the processing temperature to 450°C or higher, it is possible to form a third film with even better ashing resistance on the wafer 200.

[0122] When the processing temperature exceeds 850°C, the excited state of H atoms (H * ) is generated in large quantities, which can make it difficult to control the processing time, etc. By setting the processing temperature at 850°C or less, an appropriate amount of H * By setting the treatment temperature to 600°C or less, an appropriate amount of H * This makes it possible to easily control the processing time and the like.

[0123] (After-purge and atmospheric pressure recovery: S503) After the plasma processing is completed, gaseous substances remaining in the processing chamber 501 are removed from the processing chamber 501 using the same processing procedures and conditions as those for the above-described purging (after-purging). Thereafter, the atmosphere in the processing chamber 501 is replaced with a purge gas, and the pressure in the processing chamber 501 is returned to normal pressure (return to atmospheric pressure).

[0124] (Wafer transported out of plasma processing apparatus 500: S504) Thereafter, the susceptor 510 is lowered to a predetermined transfer position, and the wafer 200 is transferred from the susceptor 510 onto the lift pins 507. Thereafter, the GV 1490c is opened, and the processed wafer 200 is transferred out of the processing vessel 503 (TM2400) by the vacuum transfer robot 2700. Thereafter, the processed wafer 200 is transferred into the predetermined pod 2001 in the reverse order of the wafer transfer (S300) described above. This completes the substrate processing process according to this embodiment.

[0125] (6) Effects of this mode According to this aspect, one or more of the following effects can be obtained.

[0126] (a) By performing steps a to c non-simultaneously in the order of steps a, b, and c, the formed third film (SiOC film) can be a film having both a low dielectric constant and high ashing resistance. Specifically, by removing moisture and impurities from the first film in step b, it is possible to make the second film a low-k film with a low dielectric constant. Furthermore, by making the ratio of Si-C bonds to C-H bonds in the third film larger than the ratio of Si-C bonds to C-H bonds in the first film in step c, it is possible to make the third film a film with good ashing resistance and therefore HF resistance. In this way, it is possible to make the third film (SiOC film) a film that achieves both a low dielectric constant and high processing resistance (ashing resistance (and HF resistance)).

[0127] (b) By setting the processing temperature in step c higher than that in step a, it is possible to reliably maintain the Si-C bonds contained in the second film in their original form in the third film while breaking the C-H bonds contained in the second film, thereby making it possible to reliably make the third film (SiOC film) a film with excellent ashing resistance.

[0128] In addition, if steps a and b are performed in this order without performing step c in the substrate processing process, the C-H bonds contained in the first film may not be broken. As a result, the ratio of Si-C bonds to C-H bonds in the second film may not be made larger than the ratio of Si-C bonds to C-H bonds in the first film. Therefore, the modified SiOC film may not have good ashing resistance.

[0129] Furthermore, if steps a and c are performed in this order without performing step b in the substrate processing process, the film may be cured in step c while moisture and impurities present in the first film remain in the film, which may prevent the modified SiOC film from becoming a low-dielectric constant film (low-k film).

[0130] Furthermore, in the substrate processing process, when steps a to c are performed in the order of steps a, c, and b, the modified SiOC film may not have good ashing resistance. Specifically, the SiOC film formed in step a has, in addition to C—H bonds and Si—C bonds, for example, OH groups (Si—OH bonds) on its surface, and the bonding state of the surface is not constant. When step c is performed on a SiOC film with such a surface state, the modified SiOC film may not have good ashing resistance. Even if step b is performed thereafter, there is a high possibility that the SiOC film will not be modified to have good ashing resistance.

[0131] As described above, in this embodiment, the above-mentioned effects can be obtained by performing steps a to c non-simultaneously in the order of steps a, b, and c.

[0132] <Other Aspects of the Present Disclosure> Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above embodiments and can be modified in various ways without departing from the spirit and scope of the present disclosure.

[0133] In the above-described embodiment, an example in which a film having C—H bonds and Si—C bonds (SiOC film) is formed as the first film in step a has been described. However, the present disclosure is not limited to this. For example, an SiOCN film or a SiCN film having N—H bonds and Si—N bonds may be formed as the first film.

[0134] In these cases, for example, trichloroborane (BCl3) gas can be used as a catalyst. For example, 1,4-disilabutane (SiH3CH2CH2SiH3, abbreviated as 1,4-DSB), trisilylamine (N(SiH3)3, abbreviated as TSA) gas, BTCSM gas, 1,1,3,3-tetrachloro-1,3-disilacyclobutane (C2H4Cl4Si2, abbreviated as TCDSCB) gas, dichlorosilane (SiH2Cl2, abbreviated as DCS) gas, 1,1,2,2-tetrachloro-1,2-dimethyldisilane ((CH3)2Si2Cl4, abbreviated as TCDMDS) gas, and hexachlorodisilane (Si2Cl6, abbreviated as HCDS) gas can be used as raw materials (gases). As the reactive gas, for example, ammonia (NH3) gas, oxygen (O2) gas, propylene (C3H6) gas, or triethylamine ((C2H5)3N, abbreviated as TEA) gas can be used. As described above, it is preferable to use a gas containing Si and H and at least one of C and N as the film formation gas (catalyst, raw material, reactive gas). Using these, a film may be formed on the wafer 200 by the film formation sequence shown below. As shown below, a combination of multiple raw materials and multiple reactive gases may also be used.

[0135] (BCl3 → 1,4-DSB → TSA → O2) × n → SiOCN (BTCSM → NH3 → O2) × n → SiOCN (TCDMDS → NH3) × n → SiOCN (DCS → C3H6 → NH3) × n → SiCN (TCDMDS → NH3) × n → SiCN (HCDS → TEA) × n → SiCN

[0136] The processing procedures and processing conditions when performing the substrate processing sequence (steps a to c) including step a can be, for example, the same as the processing procedures and processing conditions in the above-mentioned embodiment. Specifically, for example, step c is performed under conditions that can maintain Si-N bonds, can sever N-H bonds, and further, under conditions that Si in the third film bonds to N whose bond with H has been sever- ed. As a result, the ratio of Si-N bonds to N-H bonds in the third film can be made larger than the ratio of Si-N bonds to N-H bonds in the first film. Also, the ratio of Si-N bonds in the third film can be made larger than the ratio of Si-N bonds in the first film, and the ratio of N-H bonds in the third film can be made smaller than the ratio of N-H bonds in the first film. As a result, the same effects as those in the above-mentioned embodiment can be obtained.

[0137] In addition, inorganic chlorosilane gases such as tetrachlorosilane (SiCl4, abbreviated as STC) gas and octachlorotrisilane (Si3Cl8, abbreviated as OCTS) gas can also be used as raw materials (gases). In addition, for example, dimethylsilane (SiC2H8, abbreviated as DMS) gas and trimethylsilane (SiC3H 10 (abbreviation: TMS) gas, diethylsilane (SiC 12Alternatively, a halogen-free organic silane source gas such as 1-monochloro-1,1,2,2,2-pentamethyldisilane ((CH3)5Si2Cl, abbreviated as MCPMDS) gas may be used. Alternatively, an aminosilane gas such as tetrakis(dimethylamino)silane (Si[N(CH3)2]4, abbreviated as 4DMAS) gas, tris(dimethylamino)silane (Si[N(CH3)2]3H, abbreviated as 3DMAS) gas, bis(diethylamino)silane (Si[N(C2H5)2]2H2, abbreviated as BDEAS) gas, bis(tert-butylamino)silane (SiH2[NH(C4H9)]2, abbreviated as BTBAS) gas, or (diisopropylamino)silane (SiH3[N(C3H7)2], abbreviated as DIPAS) gas may be used. One or more of these can be used as the raw material, and in these cases, the same effects as those in the above embodiment can be obtained.

[0138] In the above-described embodiment, an example in which H gas (hydrogen elemental gas) is supplied to the wafer 200 in step c has been described. However, the present disclosure is not limited to this. For example, a gas containing at least one element selected from H, nitrogen (N), oxygen (O), and helium (He) may be supplied. Specifically, nitrogen plasma processing using N gas, nitrogen-hydrogen plasma processing using N2H2 gas, oxygen-hydrogen plasma processing using OH gas, oxygen plasma processing using O gas, and helium plasma processing using He gas may be performed. In these cases, the same effects as those of the above-described embodiment can be obtained. However, for C-H bonds, the most efficient method for breaking C-H bonds is to supply an H-containing gas and use plasma-excited H (activated species of H). This is because highly unstable hydrogen plasma reacts with the hydrogen in the C-H bonds to form stable H2. Thus, hydrogen plasma is chemically reactive with hydrogen.

[0139] In the above-described embodiment, an example has been described in which a single-wafer type apparatus is used to process substrates one by one. However, the present disclosure is not limited to this. For example, the present disclosure can also be suitably applied to a case in which a batch type substrate processing apparatus is used to process multiple substrates at once. In this case, the three processes (steps a to c) may be performed in the same processing chamber (in situ) within one apparatus. Even when such a substrate processing apparatus is used, each process can be performed using the same processing procedures and processing conditions as in the above-described embodiment, and the same effects as in the above-described embodiment can be obtained.

[0140] In the above embodiment, an example has been described in which three processes (steps a to c) are performed within one substrate processing unit 2000. However, the present disclosure is not limited to this. For example, the film forming apparatus 300, the annealing apparatus 400, and the plasma processing apparatus 500 may each be configured as separate apparatuses, and each apparatus may perform (ex situ) a corresponding one of the three processes (steps a to c).

[0141] In this specification, in addition to the above-mentioned substrate processing unit 2000, a single apparatus that performs the three processes (steps a to c) in the same processing chamber, and a group of apparatuses in which the film forming apparatus 300, the annealing apparatus 400, and the plasma processing apparatus 500 are each configured as individual apparatuses are collectively referred to as a substrate processing system.

[0142] In the above-described embodiment, an example has been described in which a SiOC film (first film) that is a low-k film is formed in step a, and the first film is subjected to a heat treatment in step b. However, the present disclosure is not limited to this. For example, steps a and b may not be performed, and a wafer having a low-k film formed on its surface that has been heat-treated may be prepared, and step c may be performed on the wafer (low-k film). In this case, the same effect as in the above-described embodiment can be obtained.

[0143] It is preferable that the recipes used for each process are individually prepared according to the process content and stored in the storage device 121c via an electric communication line or an external storage device 123. Then, when starting each process, it is preferable that the CPU 121a appropriately selects an appropriate recipe according to the process content from among the multiple recipes stored in the storage device 121c. This makes it possible to reproducibly form films with various film types, composition ratios, film qualities, and film thicknesses using a single substrate processing device. It also reduces the burden on the operator, prevents operational errors, and enables each process to be started quickly.

[0144] The above-mentioned recipes do not necessarily have to be newly created, but may be prepared by modifying an existing recipe already installed in the substrate processing apparatus, for example. When modifying a recipe, the modified recipe may be installed in the substrate processing apparatus via an electric communication line or a recording medium on which the modified recipe is recorded. Alternatively, an existing recipe already installed in the substrate processing apparatus may be directly modified by operating the input / output device 122 provided in the existing substrate processing apparatus. [Example]

[0145] Using the above-mentioned substrate processing apparatus, the following substrate processing sequence was performed to modify the SiOC film formed on the wafer by the film formation sequence shown in FIG. 7, thereby producing Samples 1 and 2.

[0146] Sample 1: (raw material + catalyst → oxidant + catalyst) × n → heat treatment (annealing treatment) → SiOC film Sample 2: (raw material + catalyst → oxidant + catalyst) × n → heat treatment (annealing treatment) → plasma-excited H gas → SiOC film

[0147] BTCSM gas was used as the raw material (gas), NH gas as the catalyst, and H O gas as the oxidant. The processing conditions were set to predetermined conditions within the range of processing conditions for each step shown in the above-mentioned embodiment.

[0148] After preparing Samples 1 and 2, the dielectric constant (k value) of each film was measured. In addition, each film of Samples 1 and 2 was subjected to an ashing process using a specified ashing device, and then etched using a 1% diluted aqueous hydrogen fluoride solution (DHF solution), and the wet etching rate (WER) was measured.

[0149] As shown in FIG. 8, the dielectric constants (k values) of the films of Samples 1 and 2 were 3.5 and 4.2, respectively, confirming that both had low dielectric constants. Furthermore, as shown in FIG. 8, the WER after ashing of the films of Samples 1 and 2 was confirmed to be >1000 Å / min and 16 Å / min, respectively. It was confirmed that the film of Sample 1, for which step c was not performed, had a high WER after ashing, i.e., poor ashing resistance. It was confirmed that the film of Sample 2, for which step c was performed, had a low WER after ashing, i.e., good ashing resistance. From the above, it was confirmed that Sample 2, for which steps a to c were performed, had a low dielectric constant and also good ashing resistance. It was confirmed that Sample 1, for which step c was not performed, had a low dielectric constant but poor ashing resistance.

[0150] <Preferred aspects of the present disclosure> Preferred aspects of the present disclosure will be described below.

[0151] (Appendix 1) According to one aspect of the present disclosure, (a) forming a low-k film on a substrate; (b) performing a heat treatment on the low-k film; (c) performing a plasma treatment on the film subjected to (b) to remove H bonded to C or N in the film, thereby increasing Si-C bonds or Si-N bonds and improving ashing resistance; A method for manufacturing a semiconductor device or a method for processing a substrate is provided.

[0152] (Appendix 2) According to another aspect of the present disclosure, preparing a substrate after heat-treating a low-k film formed on the surface; performing a plasma treatment on the low-k film to make the ratio of Si-C bonds in the low-k film greater than the ratio of C-H bonds or to make the ratio of Si-N bonds in the low-k film greater than the ratio of N-H bonds; A method for manufacturing a semiconductor device or a method for processing a substrate is provided.

[0153] (Appendix 3) According to yet another aspect of the present disclosure, (a) forming a film containing at least Si, C, H, and HO on a substrate; (b) performing a treatment on the film formed in (a) to reduce the water content in the film; (c) a step of desorbing H bonded to C or N in the film subjected to (b) to increase Si-C bonds or Si-N bonds, thereby densifying at least the surface of the film and improving ashing resistance; A method for manufacturing a semiconductor device or a method for processing a substrate is provided.

[0154] (Appendix 4) According to yet another aspect of the present disclosure, A substrate processing system, a program, or a computer-readable recording medium having the program recorded thereon that performs any of the methods of Supplementary Notes 1 to 3 is provided. [Explanation of symbols]

[0155] 200 wafers (substrates)

Claims

1. (a) forming a first film containing C—H bonds and Si—C bonds on a substrate; (b) performing a heat treatment on the first film at a treatment temperature higher than the treatment temperature in (a) to modify the first film into a second film; (c) A substrate processing method comprising the steps of generating excited hydrogen atoms by exciting elemental hydrogen gas into a plasma state, supplying the excited hydrogen atoms to the substrate to modify the second film into a third film, and making the ratio of Si-C bonds to C-H bonds in the third film greater than the ratio of Si-C bonds to C-H bonds in the first film.

2. The processing temperature in (c) is higher than the processing temperature in (a). The substrate processing method according to claim 1.

3. The processing temperature in (c) is lower than the processing temperature in (b). The substrate processing method according to claim 2.

4. (c) is carried out under conditions such that the ratio of Si-C bonds in the third film is greater than the ratio of Si-C bonds in the first film, and the ratio of C-H bonds in the third film is less than the ratio of C-H bonds in the first film. A substrate processing method according to any one of claims 1 to 3.

5. (c) is performed under conditions in which the C-H bond can be cleaved and the Si in the third film is bonded to the C whose bond with H has been cleaved. The substrate processing method according to any one of claims 1 to 3.

6. (a) In this case, a raw material containing at least C-H bonds and Si-C bonds is supplied to the substrate. A substrate processing method according to any one of claims 1 to 3.

7. (a) A step of supplying a raw material containing at least a C—H bond and a Si—C bond and a catalyst to the substrate; supplying an oxidant and a catalyst to the substrate; Perform these alternately. A substrate processing method according to any one of claims 1 to 3.

8. The raw material is a chlorosilane-based gas. The substrate processing method according to claim 7.

9. The first film, the second film, and the third film are films containing Si, O, and C. A substrate processing method according to any one of claims 1 to 3.

10. the first film is a film containing water, (b) removing the water from the first film; A substrate processing method according to any one of claims 1 to 3.

11. (a) A step of forming a first film containing N-H bonds and Si-N bonds on the substrate by performing a predetermined number of cycles including (a-1) a step of supplying a source gas containing C-H bonds and Si-C bonds to the substrate and (a-2) a step of supplying ammonia gas to the substrate, (b) performing a heat treatment on the first film at a treatment temperature higher than the treatment temperature in (a) to modify the first film into a second film; (c) A substrate processing method comprising the steps of generating excited hydrogen atoms by exciting elemental hydrogen gas into a plasma state, supplying the excited hydrogen atoms to the substrate to modify the second film into a third film, and making the ratio of Si-N bonds to N-H bonds in the third film greater than the ratio of Si-N bonds to N-H bonds in the first film.

12. (a) further includes the step of supplying oxygen gas to the substrate, The substrate processing method according to claim 11 .

13. (c) is performed under conditions that allow the Si-N bond to be retained and the N-H bond to be cleaved. The substrate processing method according to claim 11 or 12.

14. (c) is performed under conditions in which the N-H bond can be cleaved and the Si in the third film bonds to the N whose bond with H has been cleaved. The substrate processing method according to claim 11 or 12.

15. The first film, the second film, and the third film are films containing Si, O, and N. A substrate processing method according to any one of claims 1 to 3.

16. (c) is performed at a temperature between 450°C and 600°C. A substrate processing method according to any one of claims 1 to 3.

17. (a), (b), and (c) are all performed with the substrate housed in the same processing chamber. The substrate processing method according to claim 1.

18. (a) forming a first film containing C—H bonds and Si—C bonds on a substrate; (b) performing a heat treatment on the first film at a treatment temperature higher than the treatment temperature in (a) to modify the first film into a second film; (c) A method for manufacturing a semiconductor device, comprising the steps of: generating excited hydrogen atoms by exciting elemental hydrogen gas into a plasma state, supplying the excited hydrogen atoms to the substrate to modify the second film into a third film, and making the ratio of Si-C bonds to C-H bonds in the third film greater than the ratio of Si-C bonds to C-H bonds in the first film.

19. (a) A step of forming a first film containing N-H bonds and Si-N bonds on the substrate by performing a predetermined number of cycles including (a-1) a step of supplying a source gas containing C-H bonds and Si-C bonds to the substrate and (a-2) a step of supplying ammonia gas to the substrate, (b) performing a heat treatment on the first film at a treatment temperature higher than the treatment temperature in (a) to modify the first film into a second film; (c) A method for manufacturing a semiconductor device, comprising the steps of: generating excited hydrogen atoms by exciting elemental hydrogen gas into a plasma state, supplying the excited hydrogen atoms to the substrate to modify the second film into a third film, and making the ratio of Si-N bonds to N-H bonds in the third film greater than the ratio of Si-N bonds to N-H bonds in the first film.

20. a deposition gas supply system that supplies a deposition gas containing a C—H bond and a Si—C bond to the substrate; a heating mechanism for heating the substrate; a plasma generating unit that excites simple hydrogen gas into a plasma state; A control unit configured to control the film-forming gas supply system, the heating mechanism, and the plasma generation unit so as to perform the following processes: (a) supplying the film-forming gas to the substrate to form a first film containing C-H bonds and Si-C bonds on the substrate; (b) heating the substrate to perform a heat treatment on the first film at a processing temperature higher than the processing temperature in (a) to modify the first film into a second film; and (c) generating excited hydrogen atoms by exciting the elemental hydrogen gas into a plasma state, supplying the excited hydrogen atoms to the substrate to modify the second film into a third film, thereby increasing the ratio of Si-C bonds to C-H bonds in the third film to a ratio of Si-C bonds to C-H bonds in the first film. A substrate processing apparatus having:

21. A film deposition gas supply system that supplies a source gas containing C-H bonds and Si-C bonds, and ammonia gas, to the substrate, a heating mechanism for heating the substrate; a plasma generating unit that excites simple hydrogen gas into a plasma state; A control unit configured to control the film-forming gas supply system, the heating mechanism, and the plasma generation unit to perform the following processes: (a) a process of forming a first film containing N-H bonds and Si-N bonds on the substrate by performing a predetermined number of cycles including (a-1) supplying the raw material gas to the substrate and (a-2) supplying ammonia gas to the substrate; (b) a process of modifying the first film into a second film by heating the substrate and performing heat treatment on the first film at a processing temperature higher than the processing temperature in (a); and (c) a process of generating excited hydrogen atoms by exciting the elemental hydrogen gas into a plasma state and supplying the excited hydrogen atoms to the substrate to modify the second film into a third film, thereby increasing the ratio of Si-N bonds to N-H bonds in the third film to a ratio of Si-N bonds to N-H bonds in the first film. A substrate processing apparatus having:

22. (a) A procedure for supplying a film-forming gas to a substrate to form a first film containing C-H bonds and Si-C bonds on the substrate, (b) A procedure to modify the first film into a second film by heating the substrate and performing heat treatment on the first film at a processing temperature higher than the processing temperature in (a), (c) A procedure to generate excited hydrogen atoms by exciting elemental hydrogen gas into a plasma state, and to supply the excited hydrogen atoms to the substrate, thereby modifying the second film into a third film, and making the ratio of Si-C bonds to C-H bonds in the third film greater than the ratio of Si-C bonds to C-H bonds in the first film, A program that causes a circuit board processing unit to execute commands via a computer.

23. (a) A procedure to form a first film containing N-H bonds and Si-N bonds on the substrate by performing a predetermined number of cycles including (a-1) a procedure to supply a source gas containing C-H bonds and Si-C bonds to the substrate, and (a-2) a procedure to supply ammonia gas to the substrate, (b) A procedure to modify the first film into a second film by heating the substrate and performing heat treatment on the first film at a processing temperature higher than the processing temperature in (a), (c) generating excited hydrogen atoms by exciting a hydrogen elemental gas into a plasma state, and supplying the excited hydrogen atoms to the substrate to modify the second film into a third film, and making the ratio of Si—N bonds to N—H bonds in the third film greater than the ratio of Si—N bonds to N—H bonds in the first film; A program that causes a circuit board processing unit to execute commands via a computer.

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