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

Abstract

The present invention has: a support part that is provided with a support surface capable of supporting a substrate; a first supply part that supplies, to the substrate, a fluid that serves as a fluidized film on the substrate under conditions in which the fluidity of the fluid is maintained; and a second supply part that supplies an inert gas to a center portion of the back surface of the substrate in a state in which the substrate is separated by a predetermined distance from the support surface.

Description

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

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

[0002] 2. Description of the Related Art One step in the manufacturing process of a semiconductor device is to supply a fluid onto a substrate to form a film (see, for example, Patent Document 1).

[0003] International Publication No. 2021 / 171466

[0004] The present disclosure provides a technique for suppressing infiltration of a fluid onto the rear surface of a substrate when a fluid is supplied onto the substrate to form a film.

[0005] According to one aspect of the present disclosure, there is provided a technology having: a support unit having a support surface capable of supporting a substrate; a first supply unit that supplies a fluid that forms a fluid film on the substrate to the substrate under conditions that maintain the fluidity of the fluid; and a second supply unit that supplies an inert gas to a central portion of the back surface of the substrate while the substrate is spaced a predetermined distance from the support surface.

[0006] According to the present disclosure, when a fluid is supplied onto a substrate to form a film, it is possible to prevent the fluid from penetrating onto the rear surface side of the substrate.

[0007] FIG. 1 is a schematic diagram of a substrate processing apparatus 100 suitable for use in one embodiment of the present disclosure. FIG. 2 is a schematic diagram of a controller 310 of the substrate processing apparatus 100 suitable for use in one embodiment of the present disclosure, and is a block diagram illustrating a control system of the controller 310. FIG. 3(a) is a diagram illustrating a schematic configuration of a support surface 211 provided on a support unit 210 of the substrate processing apparatus 100 suitable for use in one embodiment of the present disclosure. FIG. 3(b) is a cross-sectional view of the internal structure of the support unit 210 taken along line A-A in FIG. 3(a). FIG. 4(a) is a plan view schematically illustrating the pressure distribution of an inert gas supplied into a gap D between a wafer 200 and the support unit 210. FIG. 4(b) is a side view schematically illustrating the pressure distribution of an inert gas supplied into a gap D between a wafer 200 and the support unit 210.

[0008] <One Aspect of the Present Disclosure> Hereinafter, one aspect of the present disclosure will be described with reference to the drawings. 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] (1) Structure of the Substrate Processing Apparatus As shown in FIG. 1, the substrate processing apparatus 100 is an apparatus for forming a thin film on a wafer 200 as a substrate, and is configured as a single-wafer processing apparatus.

[0010] (Processing Vessel) The substrate processing apparatus 100 includes a processing vessel 202. The processing vessel 202 is configured as, for example, a flat, sealed vessel. The processing vessel 202 is configured from, for example, a metal material such as aluminum (Al) or stainless steel (SUS). A processing chamber 201 for processing wafers 200 is formed within the processing vessel 202.

[0011] A gate valve 205 and a substrate loading / unloading port 206 adjacent to the gate valve 205 are provided on the side of the processing vessel 202. By opening the gate valve 205, it becomes possible to transfer the wafer 200 between a transfer chamber (not shown) and the processing chamber 201 via the substrate loading / unloading port 206.

[0012] (Supporting Part) A supporting part 210 that supports the wafer 200 is provided within the processing chamber 201. The supporting part 210 mainly includes a supporting surface 211 that supports (places) the wafer 200, and a supporting base 212 having the supporting surface 211 on its surface. A plurality of lift pins 207 are provided at the bottom of the processing chamber 201 below the supporting part 210. The supporting base 212 has a plurality of through holes 214 through which the lift pins 207 pass, which are provided at positions corresponding to the lift pins 207. The plurality of lift pins 207, or at least one of them, is used as a lifting part that can raise and lower the wafer 200.

[0013] The support table 212 is supported by a shaft 217. The shaft 217 passes through the bottom of the processing vessel 202 and is connected to a lifting mechanism (not shown) outside the processing vessel 202. By operating the lifting mechanism, the support table 212 can be raised and lowered via the shaft 217. An opening provided in the processing vessel 202 to allow the shaft 217 to pass through is surrounded by a bellows 219, and the inside of the processing vessel 202 is kept airtight.

[0014] When transferring (loading / unloading) the wafer 200, the support table 212 descends to a predetermined position (hereinafter also referred to as the transfer position) where the support surface 211 is lower than the height corresponding to the substrate loading / unloading port 206. At the transfer position, the upper ends of the lift pins 207 protrude significantly upward from the support surface 211, and the lift pins 207 can support the wafer 200 from below.

[0015] When the wafer 200 is processed, the support table 212 rises to a predetermined position (processing position) higher than the transfer position. In this embodiment, a plurality of processing positions (multiple stages) are provided depending on the type of processing.

[0016] For example, when performing a film formation process using a fluid, which will be described later, the support table 212 is raised to a predetermined position (hereinafter also referred to as a first processing position) that is higher than the transfer position described above and maintains a state in which the upper ends of the lift pins 207 protrude upward from the support surface 211. At the first processing position, the wafer 200 can be supported by the lift pins 207 while being spaced a predetermined distance (L in the figure) from the support surface 211, i.e., a predetermined gap D can be provided between the wafer 200 and the support surface 211. As will be described later, at the first processing position, with the wafer 200 spaced a predetermined distance from the support surface 211, an inert gas (infiltration suppression gas) can be supplied to the center of the back surface of the wafer 200, and the pressure in the gap D can be set to a state (positive pressure state) higher than the pressure in the surrounding space. As will be described later, a heater 213 is provided on the support pedestal 212, and lamps 411 are provided on the ceiling of the processing chamber 202. In the first processing position, the wafer 200 is remotely heated by radiation from the heater 213 and the lamps 411. The degree of positive pressure in the gap D and the degree of heating of the wafer 200 by radiation from the heater 213 and the lamps 411 can be adjusted by the distance L between the wafer 200 and the support surface 211. This distance L can be adjusted by the amount of elevation of the support pedestal 212, i.e., the amount by which the upper ends of the lift pins 207 protrude from the support surface 211. The heater 213 is also referred to as a substrate temperature adjustment unit because it adjusts the temperature of the wafer 200. The lamps 411 may also be included in the substrate temperature adjustment unit. Although the configuration for heating the wafer 200 has been described here, when cooling the wafer 200, a flow path for supplying a coolant such as a chiller may be provided in the substrate support unit instead of the heater 213. In this case, the substrate temperature adjusting section is composed of a flow path.

[0017] Furthermore, for example, when performing a post-treatment process described later, the support table 212 is raised to a predetermined position (hereinafter also referred to as a second processing position) that is higher than the first processing position described above and where the upper ends of the lift pins 207 are buried below the support surface 211 (or where they are flush with each other). At the second processing position, the wafer 200 can be placed directly on the support surface 211 and can be efficiently heated by thermal conduction from the support surface 211. At the second processing position, the wafer 200 can be brought close to the lamps 411 and can be efficiently heated by radiation from the lamps 411. Note that the area of ​​the support surface 211 that may directly support the wafer 200 is also referred to as a substrate placement area 230.

[0018] A supply pipe 331, which will be described later, is provided to pass through the support table 212. When the support table 212 is placed in the first processing position, the supply pipe 331 is used to supply an inert gas (infiltration suppression gas) to the center of the back surface of the wafer 200, i.e., toward the gap D between the wafer 200 and the support surface 211, and details of this will be described later.

[0019] (Heating Section) The support base 212 includes a heater 213 as a first heating section.

[0020] A lamp house 460 is provided on the ceiling of the processing chamber 202 on the front surface side of the wafer 200. The lamp house 460 is provided with a plurality of lamps 411 as a second heating unit.

[0021] (Shower Head) A shower head 300 serving as a gas dispersion mechanism is provided at the top of the processing vessel 202. An inlet hole 241 for introducing a fluid (gas, mist, liquid, etc.) into the shower head 300 is provided at the top of the processing vessel 202. A common supply pipe 240, which will be described later, is connected to the inlet hole 241.

[0022] The showerhead 300 includes a dispersion plate 254 for dispersing the fluid. The dispersion plate 254 is disposed above the support surface 211 so as to face the support surface 211. The space upstream (above) of the dispersion plate 254 is a buffer chamber 252, and the space downstream (below) of the dispersion plate 254 is the processing chamber 201. The dispersion plate 254 has a plurality of through-holes. The buffer chamber 252 communicates with the processing chamber 201 via the plurality of through-holes provided in the dispersion plate 254.

[0023] (First Supply Section) As described above, the common supply pipe 240 is connected to the introduction hole 241. The common supply pipe 240 is connected to supply pipes 251, 261, 271, and 281 to which predetermined fluids are supplied.

[0024] The supply pipes 251, 261, 271, 281 are respectively provided with mass flow controllers (MFCs) 252, 262, 272, 282 which are flow rate control devices (flow rate control parts) and valves 253, 263, 273, 283 which are on-off valves, in this order from the upstream side of the fluid flow.

[0025] A raw material is supplied from the supply pipe 251 into the processing chamber 201 via the MFC 252 , the valve 253 , the common supply pipe 240 , and the shower head 300 .

[0026] A reactant is supplied from the supply pipe 261 into the processing chamber 201 via the MFC 262 , the valve 263 , the common supply pipe 240 , and the shower head 300 .

[0027] The modifying agent is supplied from the supply pipe 271 into the processing chamber 201 via the MFC 272 , the valve 273 c , the common supply pipe 240 , and the shower head 300 .

[0028] An inert gas is supplied from the supply pipe 281 into the processing chamber 201 via the MFC 282, the valve 283, the common supply pipe 240, and the shower head 300. The inert gas supplied from the supply pipe 281 acts as a purge gas, a carrier gas, a dilution gas, etc.

[0029] A raw material supply system is mainly constituted by the supply pipe 251, the MFC 252, and the valve 253. A reactant supply system is mainly constituted by the supply pipe 261, the MFC 262, and the valve 263. A modifying agent supply system is mainly constituted by the supply pipe 271, the MFC 272, and the valve 273. A first inert gas supply system is mainly constituted by the supply pipe 281, the MFC 282, and the valve 283.

[0030] The raw material supply system and the reactant supply system constitute a first supply unit. At least one of the common supply pipe 240, the modifying agent supply system, and the first inert gas supply system may also be included in the first supply unit.

[0031] (Second Supply Section) As described above, the supply pipe 331 is provided to penetrate the support table 212. The downstream end (upper end) of the supply pipe 331 is located in the center of the support surface 211, and a supply hole 320 is opened in the center of the support surface 211. The supply pipe 331 is provided with an MFC 332 and a valve 333 in this order from the upstream side of the gas flow.

[0032] An inert gas is supplied from the supply pipe 331 via the MFC 332, the valve 333, and the supply hole 320 to the space between the support surface 211 and the backside of the wafer 200. The inert gas supplied from the supply pipe 331 is supplied to the center of the backside of the wafer 200 via the supply hole 320 during a film formation process described below, i.e., when the support table 212 is positioned at the first processing position. This creates a positive pressure state in which the pressure in the gap D between the wafer 200 and the support surface 211 is higher than the pressure in the surrounding space, making it possible to prevent a fluid such as a raw material supplied to the wafer 200 from penetrating (flowing around) to the backside of the wafer 200 during a film formation process described below. Hereinafter, the inert gas supplied from the supply pipe 331 will also be referred to as a penetration suppression gas, a wraparound prevention gas, or a barrier gas.

[0033] 3( a) and 3(b), it is preferable to arrange a flow path 321 outside the supply hole 320 within the support surface 211. The flow path 321 is a groove that opens toward the upper side of the support surface 211, and can be annular in plan view (within the support surface 211), for example, circular in shape with the supply hole 320 at its center. In this embodiment, as an example, the flow path 321 has a circular shape in plan view and is provided in one piece, but the shape and number of the flow path 321 in plan view are not limited to this.

[0034] Furthermore, the flow path 321 preferably has a plurality of distribution flow paths 322 that communicate with the supply pipe 331. Similar to the flow path 321, the distribution flow paths 322 are each configured as a groove that opens upward on the support surface 211, and preferably extend radially from the supply hole 320 toward the flow path 321 in a plan view and are connected to the flow path 321. Note that, although the present embodiment shows, as an example, a case in which eight distribution flow paths 322 are provided, the number of distribution flow paths 322 is not limited to this.

[0035] The flow path 321 and the multiple distribution flow paths 322 function to supply the inert gas (infiltration suppression gas) supplied from the supply pipe 331, which serves as a common supply flow path, not only to a single location at the center of the support surface 211 but also to a wide area including the center of the support surface 211, and to widely disperse the gas within the gap D with a uniform concentric pressure distribution and a gentle pressure gradient. This is shown in Figures 4(a) and 4(b). The grayscale in the figures represents the pressure distribution of the inert gas (infiltration suppression gas), indicating a concentric pressure distribution in which the pressure decreases as the brightness increases. To achieve this pressure state, the flow path 321 is preferably configured so that the groove width and depth are substantially equal throughout its entire length (entire circumference) and the conductance difference is within a predetermined range. Furthermore, the multiple distribution flow paths 322 are preferably configured so that the groove length, width, depth, etc. are substantially equal and the conductance difference between the distribution flow paths 322 is within a predetermined range. Furthermore, it is preferable that the included angles (central angles) between adjacent distribution channels 322 are configured to be substantially equal.

[0036] It is preferable that the flow path 321 is arranged so as to be able to supply the inert gas to the outer periphery of the back surface of the wafer 200, rather than to the center of the back surface of the wafer 200, as viewed from the through-hole 214. In other words, it is preferable that the flow path 321 is arranged so as to be able to supply the inert gas to the back surface of the wafer 200 on the outer periphery of a circle surrounding all of the multiple through-holes 214 within the support surface 211.

[0037] Furthermore, the outer shape (diameter) of the flow path 321 within the support surface 211 is preferably smaller than the outer shape (diameter) of the substrate placement area 230 within the support surface 211. That is, the flow path 321 is preferably disposed at a position a certain distance (Δr in the figure) inward from the outer edge of the substrate placement area 230 in a plan view. In a film formation process described below, the length of this distance Δr is preferably ensured to be sufficiently large so that the fluid film formed on the wafer 200 is not locally deformed at the outer periphery of the wafer 200 due to irradiation with the inert gas supplied from the flow path 321. Local deformation refers to a phenomenon in which, for example, the film thickness at the outer periphery of the wafer 200 becomes thinner or thicker than when the fluid is normally attached.

[0038] Furthermore, it is preferable that the length of the distance Δr is approximately constant along the outer periphery of the substrate mounting area 230. That is, in the film formation process described below, it is preferable that the length of this distance Δr is set to be approximately constant over the entire outer periphery of the substrate mounting area 230 so that the pressure on the back surface of the wafer 200 is constant along the outer periphery of the wafer 200.

[0039] A second inert gas supply system is mainly constituted by the supply pipe 331, the MFC 332, and the valve 333. A second supply unit is mainly constituted by the supply pipe 331, the distribution flow path 322, and the flow path 321. The second inert gas supply system may be included in the second supply unit.

[0040] (Exhaust System) As shown in FIG. 1 , an exhaust port 245 for exhausting the atmosphere inside the processing chamber 201 is provided at the bottom of the processing vessel 202. An exhaust pipe 246 is connected to the exhaust port 245. A vacuum pump 248 serving as a vacuum exhaust device is connected to the exhaust pipe 246 via an APC (Auto Pressure Controller) valve 247 that controls the pressure inside the processing chamber 201 to a predetermined level. The APC valve 247 is configured to evacuate and stop the vacuum exhaust inside the processing chamber 201 by opening and closing the valve while the vacuum pump 248 is operating. The exhaust port 245, the exhaust pipe 246, and the APC valve 247 mainly constitute an exhaust system. The vacuum pump 248 may be included in the exhaust system.

[0041] (Controller) The substrate processing apparatus 100 includes a controller 310 that controls the operation of each part of the substrate processing apparatus 100 .

[0042] An outline of the controller 310 is shown in Fig. 2. The controller 310, which is a control unit (control means), is configured as a computer including a CPU (Central Processing Unit) 310a, a RAM (Random Access Memory) 310b, a storage device 310c, an I / O port 310d, and a transmitting / receiving unit 310e. The RAM 310b, the storage device 310c, and the I / O port 310d are configured to be able to exchange data with the CPU 310a via an internal bus 310f.

[0043] The controller 310 is configured so that an input / output device 311 configured as, for example, a touch panel, and an external storage device 312 can be connected thereto.

[0044] The storage device 310c is composed of, for example, a flash memory, an HDD (Hard Disk Drive), etc. Control programs for controlling the operation of the substrate processing apparatus 100, program recipes describing procedures and conditions for substrate processing (described later), etc., are readably recorded and stored in the storage device 310c. A process recipe is a combination of procedures in a substrate processing process (described later) that are executed by the controller 310 to obtain a predetermined result, and functions as a program. Hereinafter, the program recipes, control programs, etc. are collectively referred to simply as a program (program product). In this specification, the term "program" may refer to only a program recipe, only a control program, or both. The RAM 310b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 310a.

[0045] The I / O port 310d is connected to each component of the substrate processing apparatus 100, such as the gate valve 205, the heater 213, the lamp 411, the APC valve 247, the vacuum pump 248, the MFCs 252, 262, 272, 282, and 332, and the valves 253, 263, 273, 283, and 333.

[0046] The CPU 310a is configured to read and execute a control program from the storage device 310c, and to read a process recipe from the storage device 310c in response to an input of an operation command from the input / output device 311. The CPU 310a is configured to be able to control the opening and closing operation of the gate valve 205, the on / off operation and temperature adjustment operation of the heater 213, the on / off operation and temperature adjustment operation of the lamp 411, the pressure adjustment operation of the APC valve 247, the operation of the vacuum pump 248, and the like, in accordance with the contents of the read process recipe.

[0047] The controller 310 is not limited to being configured as a dedicated computer, but may also be configured as a general-purpose computer. For example, the controller 310 according to this embodiment can be configured by preparing an external storage device 312 (e.g., a magnetic tape, a magnetic disk such as a flexible disk or hard disk, an optical disk such as a CD or DVD, or a semiconductor memory such as a USB memory or memory card) storing the above-described program and installing the program on a general-purpose computer using the external storage device 312. The means for supplying the program to the computer is not limited to supplying the program via the external storage device 312. For example, the program may be supplied via a communication means such as the Internet or a dedicated line, without going through the external storage device 312. The storage device 310c and the external storage device 312 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to as recording media. In this specification, the term "recording medium" may refer to the storage device 310c alone, the external storage device 312 alone, or both.

[0048] (2) Substrate Processing Step: A method of processing a substrate (processing method) as one step in a semiconductor device manufacturing process (manufacturing method) using the above-described substrate processing apparatus 100, i.e., an example of a processing sequence for forming a film on the surface of a wafer 200 as a substrate, will be described. In the following description, the operation of each component of the substrate processing apparatus 100 is controlled by a controller 310.

[0049] The processing sequence in this embodiment includes the following steps: Step A: placing the wafer 200 on a support part 210 having a support surface 211 capable of supporting the wafer 200; Step B: supplying the wafer 200 with a fluid that forms a fluid film on the wafer 200 under conditions that maintain the fluidity of the fluid; and Step C: supplying an inert gas to the center of the back surface of the wafer 200 while the wafer 200 is spaced a predetermined distance from the support surface 211.

[0050] Specifically, in the film formation process described below, at least part of processes B and C are performed simultaneously to form a fluid film on the wafer 200 while suppressing fluid from penetrating the backside of the wafer 200. In addition, in the post-treatment process described below, process A is performed to densify the film formed on the wafer 200 while the wafer 200 is placed on the support surface 211.

[0051] The term "wafer" used in this specification may refer to the wafer itself or to a laminate of the wafer and a predetermined layer or film formed on its surface. The term "surface of a wafer" used in this specification may refer to the surface of the wafer itself or to the surface of a predetermined layer or the like formed on the wafer. When described in this specification, "forming a predetermined layer on the surface of a wafer" may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. When used in this specification, the term "substrate" is synonymous with the term "wafer".

[0052] Furthermore, the terms "raw material," "reactant," "modifier," and "substance" used in this specification include at least one of a gaseous substance and a liquid substance. A liquid substance includes a mist-like substance. That is, each of the raw material, reactant, and modifier may contain a gaseous substance, a liquid substance such as a mist-like substance, or both.

[0053] (Substrate Loading and Placing Process) The support table 212 is lowered to the above-mentioned transfer position, and the upper ends of the lift pins 207 are made to protrude a predetermined height from the support surface 211. Subsequently, the gate valve 205 is opened, and the wafer 200 is loaded into the processing chamber 201 and transferred onto the lift pins 207. The wafer 200 is supported in a horizontal position on the lift pins 207. After the wafer 200 is loaded into the processing chamber 201, the gate valve 205 is closed to hermetically seal the processing container 202. This process is also called a substrate preparation process.

[0054] (Atmosphere Adjustment Process) After the wafer 200 has been loaded, the processing chamber 201, i.e., the space in which the wafer 200 is present, is evacuated (reduced pressure exhausted) by the vacuum pump 248 so that the interior of the processing chamber 201 is at a desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by a pressure sensor, and the APC valve 247 is feedback-controlled based on this measured pressure information. In addition, the temperature of the wafer 200 in the processing chamber 201 is adjusted by a substrate temperature adjustment unit as necessary so that the desired processing temperature is reached.

[0055] (Film Forming Step) After the atmosphere adjusting step, the film forming step is carried out.

[0056] In this step, first, the support table 212 is moved to a first processing position that is higher than the transfer position. As described above, at the first processing position, the upper ends of the lift pins 207 are maintained in a state in which they protrude upward from the support surface 211, so that the wafer 200 is supported by the lift pins 207 while being spaced a distance L from the support surface 211, i.e., a gap D can be provided between the wafer 200 and the support surface 211.

[0057] At this time, it is preferable to adjust the length of the distance L ensured between the back surface of the wafer 200 and the support surface 211 by the amount of protrusion of the lift pins 207 from the support surface 211. This distance L can be set according to the amount of warping of the wafer 200. For example, if the amount of warping of the wafer 200 is large, the distance L can be set to be longer, and if the amount of warping of the wafer 200 is small, the distance L can be set to be shorter. This distance L can also be set according to the type of wafer 200. For example, if the wafer 200 is a substrate that has undergone film formation processing, the amount of warping is expected to be large, so the distance L can be set to be longer. If the wafer 200 is a bare wafer, the amount of warping is expected to be small, so the distance L can be set to be shorter. In this way, the wafer 200 can be supported without the back surface of the wafer 200 coming into contact with the support surface 211. This makes it possible to avoid phenomena such as inert gas being unable to pass through due to contact points between the back surface of the wafer 200 and the support surface 211.

[0058] After adjusting the length of the distance L, an inert gas (infiltration suppression gas) is supplied from the second supply unit to the back surface of the wafer 200, i.e., toward the gap D between the wafer 200 and the support surface 211. Specifically, the valve 333 is opened to allow the inert gas to flow into the supply pipe 331. The inert gas is supplied, with its flow rate adjusted by the MFC 332, toward the center of the back surface of the wafer 200 through the supply holes 320 provided in the support surface 211. The inert gas is also supplied from the flow path 321 and the multiple distribution paths 322 toward a wider area including the center of the back surface of the wafer 200 (infiltration suppression gas supply). As a result, as shown in FIGS. 4( a) and 4(b), when the gap D is viewed in plan, the pressure in the gap D is distributed concentrically around the supply hole 320. The pressure in the gap D also has a gentle gradient.

[0059] After a predetermined time has elapsed since the start of supplying the inert gas from the second supply unit, a fluid (including raw materials, reactants, and their decomposition products and reactants) that forms a fluid film on the surface of the wafer 200 is supplied from the first supply unit under conditions that maintain the fluidity of the fluid. Specifically, valves 253 and 263 are opened to allow the raw materials and reactants to flow into the supply pipes 251 and 261, respectively. The raw materials and reactants are respectively flow-controlled by MFCs 252 and 252, supplied into the processing chamber 201 via the common supply pipe 240 and the shower head 300, and exhausted from the exhaust port 245. At this time, the raw materials and reactants are supplied in a mixed state to the wafer 200 from above the wafer 200 (raw materials + reactant supply). At this time, valve 283 may be opened to supply an inert gas (carrier gas, dilution gas) into the processing chamber 201 via the common supply pipe 240 and the shower head 300.

[0060] By supplying the raw material and the reactant to the wafer 200 under processing conditions to be described later, a fluid film composed of the fluid can be formed on the wafer 200 while maintaining the fluidity of the raw material, the reactant, and the fluid containing their decomposition products and reaction products. The fluid contains polymers such as oligomers and polymers. Disilane (Si ２H ６ ) as a reactant and ammonia (NH ３ ) and water (H ２ O), the fluid is Si ２ H ６ , N.H. ３ , H ２ O, and polymers containing decomposition products or reaction products thereof.

[0061] In this process, the wafer 200 is kept a predetermined distance away from the support surface 211, and an inert gas (infiltration suppression gas) is supplied from the second supply unit to the center of the back surface of the wafer 200, which makes it possible to suppress infiltration of fluid into the back surface side of the wafer 200. This will be described in detail later.

[0062] After forming a fluid film on the wafer 200 while suppressing the infiltration of fluid onto the backside of the wafer 200, the valves 253 and 263 are closed, and the supply of raw materials and reactants to the wafer 200 from the first supply section is stopped.

[0063] After a predetermined time has elapsed since the supply of raw materials and reactants from the first supply unit has stopped, valve 333 is closed and the supply of inert gas (penetration suppression gas) to the back surface of wafer 200 from the second supply unit is stopped.

[0064] Thus, in this embodiment, the supply of inert gas (infiltration suppression gas) from the second supply unit begins earlier than the supply of fluid from the first supply unit, and the supply of inert gas (infiltration suppression gas) from the second supply unit is stopped later than the supply of fluid from the first supply unit is stopped.

[0065] The raw material (fluid) is a substance containing silicon (Si), for example, monosilane (SiH ４ ), Si ２ H ６ , trisilane (Si ３ H ８ ), tetrasilane (Si ４ H １０ As the raw material, one or more of these can be used.

[0066] The reactant (fluid) is a substance containing nitrogen (N), such as NH ３ , Diazene (N ２ H ２ ), hydrazine (N ２ H ４ ), N ３ H ８ One or more of these can be used as the reactant.

[0067] As the inert gas (penetration suppression gas, carrier gas, dilution gas, purge gas), nitrogen (N ２ Inert gases that can be used include rare gases such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, krypton (Kr) gas, and xenon (Xe) gas. One or more of these can be used as the inert gas.

[0068] Examples of treatment conditions for supplying the raw materials, reactants, and inert gas in this step include: treatment temperature (first temperature): 0 to 80°C, preferably room temperature (25°C) to 60°C treatment pressure: 1 to 30,000 Pa, preferably 133 to 10,000 Pa treatment time: 1 to 180 minutes, preferably 5 to 60 minutes raw material supply flow rate: 0.02 to 2 slm, preferably 0.05 to 0.5 slm reactant supply flow rate: 0.05 to 50 slm, preferably 0.1 to 10 slm inert gas (penetration suppression gas) supply flow rate: 0.01 to 10 slm inert gas (carrier gas, dilution gas) supply flow rate: 0 to 20 slm

[0069] In this specification, when a numerical range such as "0 to 80°C" is expressed, it means that the lower limit and the upper limit are included in the range. Therefore, for example, "0 to 80°C" means "0°C or higher and 80°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 201, and the processing pressure means the pressure inside the processing chamber 201. The processing time means the time the processing continues. In addition, when the supply flow rate includes 0 slm, 0 slm means that the substance is not supplied. These also apply to the following explanations.

[0070] (Post-treatment step) Thereafter, a post-treatment step is carried out.

[0071] In this process, first, the support table 212 is moved to the second processing position, which is higher than the first processing position. As described above, in the second processing position, the wafer 200 can be placed directly on the support surface 211, and the wafer 200 can be brought closer to the lamps 411. This allows the wafer 200 to be heated efficiently (in a short time).

[0072] After the wafer 200 is transferred to the support surface 211, the output of at least one of the lamp 411 and the heater 213 is adjusted so as to change the temperature of the wafer 200 to a processing temperature (second temperature) higher than the processing temperature (first temperature) in the film formation process.

[0073] When the temperature of the wafer 200 reaches the second temperature, a modifying agent is supplied from the first supply unit to the surface of the wafer 200, i.e., to the fluid film formed on the wafer 200. Specifically, the valve 273 is opened to allow the modifying agent to flow into the supply pipe 271. The flow rate of the modifying agent is adjusted by the MFC 272, and the modifying agent is supplied into the processing chamber 201 via the common supply pipe 240 and the shower head 300, and is exhausted from the exhaust port 245. At this time, the modifying agent is supplied to the wafer 200 (modifying agent supply). At this time, the valve 283 may be opened to supply an inert gas (carrier gas, dilution gas) into the processing chamber 201 via the common supply pipe 240 and the shower head 300.

[0074] By supplying the modifier to the wafer 200 under processing conditions described below, a dehydration condensation reaction or the like occurs in the fluid film formed on the wafer 200, converting the unreacted bonding groups contained in the film, and strengthening the bonds. This makes it possible to modify the fluid film formed on the wafer 200 into a film containing strong bonds. It also makes it possible to expel excess components (impurities) contained in the fluid film formed on the wafer 200, repair defects present in the film, and densify and harden the film.

[0075] After the fluid film formed on the wafer 200 has been densified, the valve 273 is closed to stop the supply of the modifying agent from the first supply unit into the processing chamber 201 .

[0076] The modifiers include oxygen (O ２ ) gas, ozone (O ３ ) Gas, O ２ Gas + Hydrogen (H ２ ) Gas, O ２ Gas + Deuterium (D ２ ) Gas, O ３ Gas + H ２ Gas, O ３ Gas + D ２ Gas, hydrogen peroxide (H ２ O ２ ) gas, water vapor (H ２ O gas), nitrous oxide (N ２ O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO ２ ) gas, carbon dioxide (CO ２ Oxygen-containing gases such as carbon monoxide (CO) gas and the like can be used. ２ Gas + H ２ In the case of a description of two gases, such as "O gas", ２ Gas and H ２ When supplying a mixed gas, the two gases may be mixed (premixed) in a supply pipe and then supplied into the processing chamber 201, or the two gases may be supplied separately into the processing chamber 201 through different supply pipes and then mixed (postmixed) in the processing chamber 201.

[0077] In addition, the modifier is H ２ hydrogen-containing gases such as D ２ A deuterium-containing gas such as a gas can be used.

[0078] As the modifier, one or more of these can be used.

[0079] Examples of treatment conditions when supplying the modifier in this step include: treatment temperature (second temperature): 100 to 1000°C, preferably 200 to 600°C; treatment pressure: 10 to 80000 Pa, preferably 200 to 6000 Pa; treatment time: 300 to 10800 seconds; and modifier supply flow rate: 0.01 to 20 slm.

[0080] (After-Purge and Atmospheric Pressure Return Process) After the post-treatment process is completed, an inert gas is supplied from the first supply unit into the process chamber 201. At this time, the APC valve 247 is opened to its maximum degree of opening to evacuate the process chamber 201. This purges the process chamber 201 and the shower head 300 (after-purge). Thereafter, the atmosphere in the process chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure in the process chamber 201 is returned to normal pressure (atmospheric pressure return).

[0081] (Substrate Unloading Process) Thereafter, the processed wafer 200 is unloaded from the processing chamber 202 in the reverse order of the substrate loading / placing process described above. Thereafter, a predetermined process is performed on the processed wafer 200 as necessary.

[0082] (4) Effects of this aspect This aspect provides one or more of the following effects.

[0083] (a) In the film formation process, by supplying a fluid such as a raw material to the wafer 200 while the wafer 200 is kept a predetermined distance away from the support surface 211, it is possible to avoid the occurrence of capillary action between the back surface of the wafer 200 and the support surface 211 and to suppress the penetration of the fluid into the back surface side of the wafer 200.

[0084] Furthermore, in the film formation process, when supplying fluids such as raw materials to the wafer 200, an inert gas (penetration suppression gas) is supplied to the center of the back surface of the wafer 200, thereby creating a positive pressure state in the gap D between the wafer 200 and the support surface 211, making it possible to suppress the penetration of fluids into the back surface of the wafer 200.

[0085] This makes it possible to suppress the formation of a film between the back surface of the wafer 200 and the support surface 211, or on the outer periphery of the wafer 200. As a result, it becomes possible to prevent the wafer 200 from sticking to the support surface 210 and the generation of particles in the processing chamber 201.

[0086] For reference, the problems with the prior art will be explained below.

[0087] When a warped or warped wafer 200 is placed on the support surface 211, the back surface of the wafer 200 may have some areas that contact the support surface 211 and some areas that do not. In other words, a small gap may be formed between the wafer 200 and the support surface 211. In this state, when a fluid such as a raw material is supplied to the wafer 200 during a film formation process, capillary action occurs in the small gap, and the fluid may penetrate into the gap. As a result, a film may be formed in the gap, causing the wafer 200 to stick to the support surface 211, or particles may be generated when the wafer 200 is peeled off. Furthermore, if the fluid penetrates into the gap, the wafer 200 may move on the support surface 211 during the film formation process and fall off the substrate placement area 230. As a result, it may be difficult for a wafer transfer machine to pick up the wafer 200 during the subsequent substrate removal process.

[0088] (b) In the film formation process, the distance L between the wafer 200 and the support surface 211 can be flexibly controlled according to various conditions by adjusting the amount of protrusion of the lift pins 207 from the support surface 211. As a result, it is possible to effectively prevent fluid from penetrating the backside of the wafer 200.

[0089] For example, in the film formation process, contact between the wafer 200 and the support surface 211 can be avoided by setting the distance L between the wafer 200 and the support surface 211 in accordance with the amount of warpage of the wafer 200. This makes it possible to effectively prevent fluid from penetrating into the backside of the wafer 200. Note that the amount of warpage of the wafer 200 referred to here includes both the amount of warpage that actually occurs in the wafer 200 and the amount of warpage that is predicted for the wafer 200.

[0090] Furthermore, for example, in the film forming process, contact between the wafer 200 and the support surface 211 can be avoided by setting the distance L between the wafer 200 and the support surface 211 according to the type of wafer 200. This makes it possible to effectively suppress infiltration of fluid to the back side of the wafer 200.

[0091] (c) Since the second supply unit has a supply hole 320 that supplies an inert gas toward the center of the back surface of the wafer 200, an appropriate positive pressure state is created in the gap D between the wafer 200 and the support surface 211 during the film formation process, making it possible to effectively suppress the penetration of fluid into the back surface of the wafer 200.

[0092] (d) Since the second supply unit is provided with the flow path 321, in the film forming process, the inert gas supplied from the supply pipe 331 can be supplied to a wide area including the center of the support surface 211, and can be widely dispersed within the gap D with a uniform concentric pressure distribution and a gentle pressure gradient. This makes it possible to effectively suppress the infiltration of the fluid to the backside of the wafer 200.

[0093] Furthermore, by arranging the flow path 321 at a position that is a certain distance Δr inward from the outer edge of the substrate mounting area 230 in a planar view, it is possible to prevent the fluid film formed on the wafer 200 from being locally deformed (such as becoming thinner) at the outer periphery of the wafer 200 during the film formation process.

[0094] Furthermore, by making the length of the distance Δr approximately constant along the outer periphery of the substrate mounting region 230, it is possible to make the pressure on the backside of the wafer 200 constant along the outer periphery of the wafer 200 in the film forming process. This makes it possible to effectively suppress the infiltration of fluid into the backside of the wafer 200 over the entire outer periphery of the wafer 200.

[0095] (e) By configuring the flow path 321 so that the groove width and depth are substantially equal over its entire length (entire circumference) and the difference in conductance is within a predetermined range, and by configuring the multiple distribution flow paths 322 so that the groove length, width, depth, etc. are substantially equal and the difference in conductance is within a predetermined range, it becomes possible to widely disperse the inert gas (infiltration suppression gas) supplied from the supply pipe 331 within the gap D with a uniform concentric pressure distribution and a gentle pressure gradient. This makes it possible to effectively suppress infiltration of fluid into the backside of the wafer 200 over the entire backside of the wafer 200.

[0096] (f) By the second supply unit supplying an inert gas to the back surface of the wafer 200 on the outer periphery side as viewed from the through hole 214, it becomes possible to suppress the infiltration of fluid into the through hole 214 during the film formation process.

[0097] Furthermore, when the second supply unit surrounds the multiple through holes 214 in a circle, by supplying an inert gas to the back surface of the wafer 200 on the outer periphery of this circle, it becomes possible to suppress the infiltration of fluid into the through holes 214 during the film formation process.

[0098] (g) In the film forming process, by starting the supply of the inert gas (penetration suppression gas) earlier than the supply of the fluid, it is possible to effectively suppress the penetration of the fluid into the backside of the wafer 200.

[0099] Furthermore, in the film forming process, by stopping the supply of the inert gas (infiltration suppression gas) later than the supply of the fluid, it is possible to effectively suppress the infiltration of the fluid onto the backside of the wafer 200 .

[0100] Other Aspects of the Present Disclosure The above describes specific aspects of the present disclosure. However, the present disclosure is not limited to the above aspects and can be modified in various ways without departing from the spirit and scope of the present disclosure.

[0101] For example, in the above-described embodiment, the support part 210 is raised to a first processing position higher than the transfer position during the film formation process, but the present disclosure is not limited to this embodiment. For example, the film formation process may be performed while the support part 210 remains in the transfer position. However, raising the support part 210 to the first processing position is preferable because it makes it easier to appropriately narrow the distance L between the wafer 200 and the support surface 211 during the film formation process and to make the pressure in the gap D positive.

[0102] In the above-described embodiment, the support part 210 is raised to the second processing position, which is higher than the first processing position, during the pre-coating step. However, the present disclosure is not limited to this embodiment. For example, the pre-coating step may be performed while the support part 210 remains in the first processing position, or the support part 210 may be lowered to the transfer position before the pre-coating step. However, raising the support part 210 to the second processing position is preferable because it allows the wafer 200 to be heated more efficiently during the pre-coating step.

[0103] It is preferable that the recipes used for each process are individually prepared according to the process content and recorded and stored in the storage device 310c via an electric communication line or the external storage device 312. When starting each process, it is preferable that the CPU 310a appropriately selects an appropriate recipe according to the process content from among the multiple recipes recorded and stored in the storage device 310c. This enables the processing device to reproducibly form films with various film types, composition ratios, film qualities, and film thicknesses. It also reduces the burden on the operator, avoids operational errors, and enables each process to be started quickly.

[0104] The above-mentioned recipes do not necessarily have to be newly created, but may be prepared by modifying an existing recipe that has already been installed in the processing device. When modifying a recipe, the modified recipe may be installed in the processing device via an electric communication line or a recording medium on which the recipe has been recorded. Furthermore, an existing recipe that has already been installed in the processing device may be directly modified by operating the input / output device 311 provided in the existing processing device.

[0105] In the above-described embodiment, an example in which the film formation process and the post-treatment process are performed in a single apparatus has been described, but the present disclosure is not limited to this, and the film formation process and the post-treatment process may be performed in separate apparatuses or separate treatment chambers. Furthermore, in the above-described embodiment, an example in which a film is formed using a treatment apparatus having a hot-wall type treatment furnace has been described. However, the present disclosure is not limited to the above-described embodiment, and can also be suitably applied to the case in which a film is formed using a treatment apparatus having a cold-wall type treatment furnace.

[0106] In the above embodiment, an example has been described in which the fluid supplied from the shower head 300 has fluidity, but the present invention is not limited to this. It is sufficient that the fluidity is maintained above the wafer 200. For example, either the source material or the reactant constituting the fluid may be directly supplied to the processing chamber 201. That is, the source material and the reactant may be supplied separately to the processing chamber 201. In this case, it is sufficient that the source material and the reactant are mixed in the processing chamber 201 and the fluidity of the fluid is maintained above the wafer 200.

[0107] In the above embodiment, an example of using a fluid in which a raw material and a reactant are mixed has been described, but the present invention is not limited to this, and any fluid may be used as long as the fluidity is maintained on the wafer 200. For example, tetraethyl orthosilicate (Si(OC ２ H ５ ) ４、 In this case, TEOS may be supplied in mist form onto the substrate and irradiated with vacuum ultraviolet light to give the TEOS fluidity.

[0108] The above-described embodiments and modifications may be used in combination as appropriate. The processing procedures and processing conditions in such a case may be the same as those of the above-described embodiments and modifications, for example.

[0109] 200 Wafer (substrate) 211 Support surface 210 Support portion

Claims

1. A substrate processing apparatus having: a support unit with a support surface capable of supporting a substrate; a first supply unit that supplies a fluid that forms a fluid film on the substrate to the substrate under conditions that maintain the fluidity of the fluid; and a second supply unit that supplies an inert gas to a central portion of the back surface of the substrate while the substrate is spaced a predetermined distance from the support surface.

2. The substrate processing apparatus according to claim 1, further comprising a lifting section whose upper end protrudes from the support surface and which is capable of supporting and lifting the substrate, and wherein the predetermined distance is adjusted by the amount of protrusion of the upper end from the support surface.

3. The substrate processing apparatus according to claim 1, wherein the predetermined distance is set in accordance with the amount of warping of the substrate.

4. The substrate processing apparatus according to claim 1, wherein the predetermined distance is set according to the type of the substrate.

5. The substrate processing apparatus according to claim 1, wherein the second supply unit has a supply hole for supplying the inert gas toward the center of the rear surface of the substrate.

6. The substrate processing apparatus according to claim 1, wherein the second supply section has a flow path at a position spaced a certain distance inward from the outer edge of the substrate placement area on the support surface.

7. The substrate processing apparatus according to claim 6, wherein the predetermined distance is a distance at which the fluid film formed on the substrate is not deformed by the inert gas at the outer periphery of the substrate.

8. The substrate processing apparatus according to claim 1, wherein the inert gas is supplied from the second supply unit to the rear surface of the substrate so that a constant pressure is maintained along the outer periphery of the substrate.

9. The substrate processing apparatus according to claim 5, wherein the second supply section has a flow path at a position a certain distance inward from the outer edge of the substrate placement area on the support surface, the flow path having a plurality of distribution flow paths connected to a supply pipe having the supply hole, and the lengths of the respective distribution flow paths are configured to be equal.

10. The substrate processing apparatus according to claim 2, wherein the support section is provided with a through hole through which the lifting section passes, and the second supply section is capable of supplying the inert gas to the back surface of the substrate on the outer periphery side as viewed from the through hole.

11. The substrate processing apparatus of claim 2, wherein the support section is provided with a plurality of through holes through which the lifting section passes, and the second supply section is capable of supplying the inert gas to the back surface of the substrate on the outer periphery of a circle surrounding the plurality of through holes.

12. The substrate processing apparatus according to claim 1, wherein the supply of the inert gas is started earlier than the supply of the fluid.

13. The substrate processing apparatus according to claim 1, wherein the supply of the inert gas is stopped later than the supply of the fluid.

14. The substrate processing apparatus of claim 1, wherein the fluid includes a polymer.

15. The substrate processing apparatus according to claim 14, wherein the polymer contains disilane and ammonia.

16. The substrate processing apparatus according to claim 1, wherein the fluid is supplied in the form of a mist.

17. A substrate processing method comprising the steps of: placing a substrate on a support having a support surface capable of supporting the substrate; supplying a fluid that forms a fluid film on the substrate to the substrate under conditions that maintain the fluidity of the fluid; and supplying an inert gas to the center of the back surface of the substrate while the substrate is spaced a predetermined distance from the support surface.

18. A method for manufacturing a semiconductor device, comprising the steps of: placing a substrate on a support having a support surface capable of supporting the substrate; supplying a fluid that forms a fluid film on the substrate to the substrate under conditions that maintain the fluidity of the fluid; and supplying an inert gas to the center of the back surface of the substrate while the substrate is spaced a predetermined distance from the support surface.

19. A program that causes a substrate processing apparatus to execute, by a computer, the following steps: placing a substrate on a support section having a support surface capable of supporting the substrate; supplying a fluid that forms a fluid film on the substrate to the substrate under conditions that maintain the fluidity of the fluid; and supplying an inert gas to the center of the back surface of the substrate while the substrate is spaced a predetermined distance from the support surface.

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