Method for processing substrate, method for manufacturing semiconductor device, substrate processor, and program

Abstract

To provide a technique capable of improving the uniformity of a film formed on the surface of a substrate.SOLUTION: The method for processing a substrate includes steps of: (a) supplying a first gas, which blocks a second gas from adsorbing to a first adsorption site, to a substrate having a predetermined surface in which the first adsorption site exists; and (b) supplying the second gas to the substrate under the condition that the amount of adsorption of the second gas onto the predetermined surface becomes self-restraining. Step (a) and Step (b) are started concurrently or Step (a) is started earlier than Step (b). The first gas is adsorbed more than the second gas on the predetermined surface.SELECTED DRAWING: Figure 4

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] 2. Description of the Related Art As one step of a substrate processing process (a manufacturing process of a semiconductor device), a step of forming a film on the surface of a substrate using a reaction inhibiting gas is sometimes performed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-110465 A Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides a technique capable of improving the uniformity of a film formed on a substrate surface. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, (a) supplying a first gas to a substrate having a predetermined surface on which first adsorption sites are present, the first gas inhibiting adsorption of a second gas to the first adsorption sites; (b) supplying the second gas to the substrate under conditions such that the amount of adsorption of the second gas onto the predetermined surface is self-limiting; (a) commences simultaneously with or before (b); The first gas is more highly adsorbed on the given surface than the second gas. Effect of the Invention

[0006] According to the present disclosure, it is possible to improve the uniformity of a film formed on a substrate surface. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitably used in one embodiment of the present disclosure, showing a processing furnace 202 portion in vertical cross section. [Diagram 2] FIG. 2 is a schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus preferably used in one embodiment of the present disclosure, showing a processing furnace 202 portion in a cross-sectional view taken along line AA in FIG. [Diagram 3] FIG. 3 is a schematic configuration diagram of a controller 121 of a substrate processing apparatus suitably used in one embodiment of the present disclosure, and is a block diagram showing a control system of the controller 121. [Figure 4] 4(a) to 4(c) are partial enlarged cross-sectional views showing an example of a substance formed in each step of a processing sequence in one embodiment of the present disclosure. FIG. 4(a) is a partial enlarged cross-sectional view of the surface of the wafer 200 after a first gas is adsorbed onto the surface of the wafer 200. FIG. 4(b) is a partial enlarged cross-sectional view of the surface of the wafer 200 after the first gas and the second gas are adsorbed onto the surface of the wafer 200 to form a first layer 300. FIG. 4(c) is a partial enlarged cross-sectional view of the surface of the wafer 200 after the first layer 300 formed on the surface of the wafer 200 is modified into a second layer 400 by a third gas. [Diagram 5] FIG. 5 is a partially enlarged cross-sectional view of a film formed on the surface of a wafer 200 in the first modification of the present disclosure. [Figure 6]6(a) to 6(c) are partial enlarged cross-sectional views showing an example of a substance formed in each step of a processing sequence in the second modification of the present disclosure. FIG. 6(a) is a partial enlarged cross-sectional view of the surface of the wafer 200 after the first gas and the second gas are adsorbed on the surface of the wafer 200 to form a first layer 300. FIG. 6(b) is a partial enlarged cross-sectional view of the surface of the wafer 200 after the first gas of the first gas and the second gas adsorbed on the surface of the wafer 200 is removed. FIG. 6(c) is a partial enlarged cross-sectional view of the surface of the wafer 200 after the fourth gas is adsorbed on the surface of the wafer 200 after the first gas is removed to form a third layer 600. [Figure 7] FIG. 7 is a diagram showing the relationship between the supply time of the first gas per cycle and the concentration of the second element in a film when a film is formed using a process sequence according to one embodiment of the present disclosure. [Figure 8] FIG. 8 is a diagram showing the relationship between the supply amount of the second gas per cycle and the concentration of the second element in the film when the film is formed using the process sequence according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] <One aspect of the present disclosure> Hereinafter, one embodiment of the present disclosure will be described mainly with reference to Figures 1 to 3 and Figures 4(a) to 4(c). Note that the drawings used in the following description are all schematic, and the dimensional relationships of the elements, the ratios of the elements, etc. shown in the drawings do not necessarily match the actual ones. Furthermore, the dimensional relationships of the elements, the ratios of the elements, etc. between multiple drawings do not necessarily match.

[0009] (1) Configuration of the substrate processing device 1, the process furnace 202 has a heater 207 as a temperature control unit (heating unit). The heater 207 is cylindrical and is installed vertically by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) gas by heat.

[0010] A reaction tube 203 is disposed concentrically with the heater 207 inside the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC) and is formed in a cylindrical shape with a closed upper end and an open lower end. A manifold 209 is disposed concentrically with the reaction tube 203 below the reaction tube 203. The upper end of the manifold 209 is engaged with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a is provided as a sealing member between the manifold 209 and the reaction tube 203. The reaction tube 203 is installed vertically like the heater 207. The reaction tube 203 and the manifold 209 mainly constitute a processing vessel (reaction vessel). A processing chamber 201 is formed in a cylindrical hollow portion of the processing vessel. The processing chamber 201 is configured to be able to accommodate a wafer 200 as a substrate. In the processing chamber 201, processing of a wafer 200 is performed.

[0011] Nozzles 249a to 249c serving as first to third supply units are provided in the processing chamber 201 so as to penetrate the sidewall of the manifold 209, respectively. The nozzles 249a to 249c are also referred to as first to third nozzles, respectively. The nozzles 249a to 249c are made of a heat-resistant material such as quartz or SiC. Gas supply pipes 232a to 232c are connected to the nozzles 249a to 249c, respectively. The nozzles 249a to 249c are different nozzles, and each of the nozzles 249a and 249c is provided adjacent to the nozzle 249b.

[0012] Gas supply pipes 232a-232c are provided with mass flow controllers (MFCs) 241a-241c, which are flow rate controllers (flow rate control parts), and valves 243a-243c, which are on-off valves, in order from the upstream side of the gas flow. Gas supply pipes 232d and 232e are connected to the gas supply pipe 232a downstream of the valve 243a. Gas supply pipes 232f and 232g are connected to the gas supply pipes 232b and 232c downstream of the valves 243b and 243c, respectively. Gas supply pipes 232d-232g are provided with MFCs 241d-241g and valves 243d-243g in order from the upstream side of the gas flow.

[0013] As shown in FIG. 2, the nozzles 249a to 249c are provided in a circular space between the inner wall of the reaction tube 203 and the wafers 200 in a plan view, and are provided so as to rise upward in the arrangement direction of the wafers 200 along the inner wall of the reaction tube 203 from the lower part to the upper part. The nozzles 249a and 249c are arranged so as to sandwich a straight line L passing through the nozzle 249b and the center of the exhaust port 231a from both sides along the inner wall of the reaction tube 203 (the outer periphery of the wafers 200). The gas supply holes 250a to 250c are each opened so as to face (face) the exhaust port 231a in a plan view, and can supply gas toward the wafers 200. A plurality of the gas supply holes 250a to 250c are provided from the lower part to the upper part of the reaction tube 203.

[0014] A first gas is supplied from the gas supply pipe 232a through the MFC 241a, the valve 243a, and the nozzle 249a into the processing chamber 201. Here, the first gas is a gas that inhibits a second gas, etc. and a fourth gas, etc., described below, from being adsorbed onto the wafer 200 or the second gas, etc. and the fourth gas, etc., from being adsorbed onto the first adsorption site.

[0015] A third gas is supplied from the gas supply pipe 232b into the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b.

[0016] A fourth gas is supplied from the gas supply pipe 232c into the processing chamber 201 via the MFC 241c, the valve 243c, and the nozzle 249c.

[0017] A second gas is supplied from the gas supply pipe 232d into the processing chamber 201 via the MFC 241d, the valve 243d, the gas supply pipe 232a, and the nozzle 249a.

[0018] From the gas supply pipes 232e to 232g, an inert gas is supplied via the MFCs 241e to 241g, the valves 243e to 243g, the gas supply pipes 232a to 232c, and the nozzles 249a to 249c, respectively, into the processing chamber 201. The inert gas acts as a purge gas, a carrier gas, a dilution gas, or the like.

[0019] A first gas supply system is mainly composed of the gas supply pipe 232a, the MFC 241a, and the valve 243a. A third gas supply system is mainly composed of the gas supply pipe 232b, the MFC 241b, and the valve 243b. A fourth gas supply system is mainly composed of the gas supply pipe 232c, the MFC 241c, and the valve 243c. A second gas supply system is mainly composed of the gas supply pipe 232d, the MFC 241d, and the valve 243d. An inert gas supply system is mainly composed of the gas supply pipes 232e to 232g, the MFCs 241e to 241g, and the valves 243e to 243g.

[0020] Any or all of the various supply systems described above may be configured as an integrated supply system 248 in which the valves 243a to 243g and the MFCs 241a to 241g are integrated. The integrated supply system 248 is connected to the gas supply pipes 232a to 232g, and the supply operation of various substances (various gases) into the gas supply pipes 232a to 232h, that is, the opening and closing operation of the valves 243a to 243g and the flow rate adjustment operation by the MFCs 241a to 241g, are controlled by a controller 121 described later. The integrated supply system 248 is configured as an integrated or split type integrated unit, and can be attached and detached to and from the gas supply pipes 232a to 232g, etc., and maintenance, replacement, expansion, etc. of the integrated supply system 248 can be performed on an integrated unit basis.

[0021] An exhaust port 231a for exhausting the atmosphere in the processing chamber 201 is provided at the lower side of the side wall of the reaction tube 203. As shown in FIG. 2, the exhaust port 231a is provided at a position facing the nozzles 249a to 249c (gas supply holes 250a to 250c) across the wafer 200 in a plan view. The exhaust port 231a may be provided along the side wall of the reaction tube 203 from the lower part to the upper part, that is, along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 231a. A vacuum pump 246 as a vacuum exhaust device is connected to the exhaust pipe 231 via a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure in the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 as a pressure regulator (pressure adjustment unit). The APC valve 244 can evacuate and stop the vacuum exhaust of the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operated. The APC valve 244 is further configured to adjust the pressure inside the processing chamber 201 by adjusting the valve opening based on pressure information detected by a pressure sensor 245 while the vacuum pump 246 is in operation. An exhaust system is mainly configured by the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may be considered to be included in the exhaust system.

[0022] Below the manifold 209, a seal cap 219 is provided as a furnace port cover body capable of airtightly closing the lower end opening of the manifold 209. An O-ring 220b is provided on the upper surface of the seal cap 219 as a seal member that abuts against the lower end of the manifold 209. Below the seal cap 219, a rotation mechanism 267 is provided for rotating the boat 217 described later. A rotation shaft 255 of the rotation mechanism 267 is connected to the boat 217 through the seal cap 219. The rotation mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be raised and lowered in the vertical direction by a boat elevator 115 as a lifting mechanism installed outside the reaction tube 203. The boat elevator 115 is configured as a transfer device (transfer mechanism) that transfers the wafer 200 into and out of the processing chamber 201 by raising and lowering the seal cap 219.

[0023] A shutter 219s is provided below the manifold 209 as a furnace port cover that can air-tightly close the lower end opening of the manifold 209 when the seal cap 219 is lowered and the boat 217 is carried out of the processing chamber 201. An O-ring 220c is provided on the upper surface of the shutter 219s as a seal member that comes into contact with the lower end of the manifold 209. The opening and closing operation (lifting and lowering operation, rotating operation, etc.) of the shutter 219s is controlled by a shutter opening and closing mechanism 115s.

[0024] The boat 217 as a substrate support is configured to support multiple wafers, for example 25 to 200 wafers 200, in a horizontal position and aligned vertically with their centers aligned, i.e., arranged at intervals. The boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the boat 217, heat insulating plates 218 made of a heat-resistant material such as quartz or SiC are supported in multiple stages. In this specification, a numerical range such as "25 to 200 sheets" means that the lower limit and the upper limit are included in the range. Therefore, for example, "25 to 200 sheets" means "25 sheets or more and 200 sheets or less". The same applies to other numerical ranges.

[0025] A temperature sensor 263 serving as a temperature detector is installed in the reaction tube 203. By adjusting the power supply to the heater 207 based on temperature information detected by the temperature sensor 263, the temperature distribution in the process chamber 201 becomes a desired one. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0026] As shown in FIG. 3, 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 be connected to the controller 121. The substrate processing apparatus may be configured to include one control unit or multiple control units. That is, the control for performing the processing sequence described later may be performed using one control unit or multiple control units. The multiple control units may be configured as a control system connected to each other by a wired or wireless communication network, and the control for performing the processing sequence described later may be performed by the entire control system. In this specification, when the term "control section" is used, it may include one control section, or may include multiple control sections, or may include a control system made up of multiple control sections.

[0027] The storage device 121c is composed of, for example, a flash memory, a hard disk drive (HDD), a solid state drive (SSD), etc. In the storage device 121c, a control program for controlling the operation of the substrate processing apparatus, a process recipe in which procedures and conditions of the substrate processing described later are described, etc. are recorded and stored in a readable manner. The process recipe is a combination of procedures in the 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 recipe, the control program, etc. are collectively referred to simply as a program. In addition, the process recipe is also simply referred to as a recipe. In this specification, when the word program is used, it may include only a recipe, only a control program, or both. The RAM 121b is configured as a memory area (work area) in which the programs and data read by the CPU 121a are temporarily stored.

[0028] The I / O port 121d is connected to the above-mentioned MFCs 241a to 241g, valves 243a to 243g, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotation mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, and the like.

[0029] The CPU 121a is configured to be able 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, etc. The CPU 121a is configured to be able to control the flow rate adjustment operation of various substances (various gases) by the MFCs 241a to 241g, the opening and closing operations of the valves 243a to 243g, the opening and closing operation of the APC valve 244 and the pressure adjustment operation by the APC valve 244 based on the pressure sensor 245, the start and stop of the vacuum pump 246, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the rotation and rotation speed adjustment operation of the boat 217 by the rotation mechanism 267, the lifting and lowering operation of the boat 217 by the boat elevator 115, the opening and closing operation of the shutter 219s by the shutter opening and closing mechanism 115s, etc., in accordance with the contents of the read recipe.

[0030] The controller 121 can be configured by installing the above-mentioned program recorded and 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 are 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 of them. 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.

[0031] (2) Substrate processing A method of processing a substrate as one step in a manufacturing process of a semiconductor device using the above-mentioned substrate processing apparatus, i.e., an example of a processing sequence for forming a film on a wafer 200 as a substrate, will be described mainly with reference to Fig. 4. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by a controller 121.

[0032] In the processing sequence of this embodiment, (a) supplying a first gas that inhibits a second gas from adsorbing to the first adsorption sites to a wafer 200 having a predetermined surface on which first adsorption sites are present; (b) supplying a second gas to the wafer 200 under conditions such that the amount of adsorption of the second gas onto a predetermined surface is self-limiting; (a) commences simultaneously with or before (b); The first gas is more highly adsorbed on a given surface than the second gas.

[0033] In addition, in the following (c) forming a first adsorption site on at least a portion of the predetermined surface; A case will be described where a first cycle in which (a) and (b) are followed by (c) is performed a predetermined number of times (n times, n being an integer of 1 or 2 or more).

[0034] In addition, in the following In (c), a case will be described in which a third gas is supplied to the wafer 200 to form a first adsorption site on at least a portion of a predetermined surface.

[0035] In the following, a case will be described in which the first gas contains a first element, the second gas contains a second element, and the third gas contains a third element.

[0036] In this specification, the above-mentioned processing sequence may be expressed as follows for convenience. Similar notations will be used in the following explanations of modified examples and other aspects.

[0037] (1st gas → purge → 2nd gas → purge → 3rd gas → purge) x n

[0038] The term "wafer" used in this specification may mean the wafer itself or 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 mean the surface of the wafer itself or the surface of a predetermined layer or the like formed on the wafer. When it is stated in this specification that "a predetermined layer is formed on a wafer", it may mean that a predetermined layer is formed directly on the surface of the wafer itself or that a predetermined layer is formed on a layer or the like formed on the wafer. When the term "substrate" is used in this specification, it is synonymous with the term "wafer".

[0039] The term "agent" used in this specification includes at least one of a gaseous substance and a liquid substance. A liquid substance includes a mist substance. That is, each of the first raw material, the second raw material, and the oxidizing agent may include a gaseous substance, a liquid substance such as a mist substance, or both.

[0040] As used herein, the term "layer" includes at least one of a continuous layer and a discontinuous layer. For example, the first layer 300 and the second layer 400 described below may include a continuous layer, a discontinuous layer, or both.

[0041] In this specification, when the first gas, second gas, third gas, and fourth gas are mentioned as being adsorbed to or reacting with the surface of the wafer 200, this may include not only the manner in which they are adsorbed to or reacted with the wafer surface while remaining undecomposed, but also the manner in which they are decomposed, or intermediates generated by the detachment of their ligands are adsorbed to or reacted with the surface of the wafer 200.

[0042] (Wafer charge and boat load) When a plurality of wafers 200 are loaded into the boat 217 (wafer charge), the shutter 219s is moved by the shutter opening / closing mechanism 115s to open the lower end opening of the manifold 209 (shutter open). Thereafter, as shown in FIG. 1, the boat 217 supporting the plurality of wafers 200 is lifted by the boat elevator 115 and carried into the processing chamber 201 (boat load). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b. In this manner, the wafers 200 are prepared (provided) in the processing chamber 201.

[0043] The wafers 200 loaded into the boat 217 have a predetermined surface on which the first adsorption sites are present. In this embodiment, as an example, a case where the first adsorption sites are present on the predetermined surface of the wafers 200 will be described. The wafers 200 may have a surface on which a material different from the material constituting the predetermined surface is exposed.

[0044] (Pressure and temperature regulation) After the boat loading is completed, the inside of the processing chamber 201, i.e., the space in which the wafers 200 are present, is evacuated (reduced pressure exhaust) by the vacuum pump 246 so that the inside 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 the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure information. Also, the wafers 200 in the processing chamber 201 are heated by the heater 207 so that the wafers 200 are at a desired processing temperature. At this time, the power supply to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the inside of the processing chamber 201 has a desired temperature distribution. Also, the rotation mechanism 267 starts rotating the wafers 200. The evacuation inside the processing chamber 201 and the heating and rotation of the wafers 200 are all continued at least until the processing of the wafers 200 is completed.

[0045] (Film formation process) Then, the following steps A, B, and C are executed in sequence.

[0046] [Step A] In this step, a first gas is supplied to the wafer 200 in the processing chamber 201 .

[0047] Specifically, the valve 243a is opened to allow the first gas to flow into the gas supply pipe 232a. The flow rate of the first gas is adjusted by the MFC 241a, and the first gas is supplied into the processing chamber 201 through the nozzle 249a and exhausted from the exhaust port 231a. At this time, the first gas is supplied to the wafer 200 from the side of the wafer 200 (first gas supply). At this time, the valves 243e to 243g may be opened to supply an inert gas into the processing chamber 201 through each of the nozzles 249a to 249c.

[0048] The processing conditions for supplying the first gas in this step are as follows: Treatment temperature: 350 to 700°C, preferably 500 to 600°C Treatment pressure: 1 to 10,000 Pa, preferably 10 to 1,333 Pa First gas supply flow rate: 0.01 to 3 slm, preferably 0.1 to 1 slm First gas supply time: 10 to 120 seconds, preferably 20 to 60 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm Examples are given below.

[0049] In this specification, the process temperature means the temperature of the wafer 200 or the temperature inside the process chamber 201, and the process pressure means the pressure inside the process chamber 201, in other words, the pressure of the space in which the wafer 200 exists. In addition, when the supply flow rate includes 0 slm, 0 slm means a case where the gas (substance) is not supplied. These are the same in the following explanation.

[0050] By supplying the first gas to the wafer 200 under the above-mentioned processing conditions, at least one of the first gas, a substance having a part of the molecular structure of the first gas, and a first element contained in the first gas can be adsorbed to the first adsorption sites present on the surface of the wafer 200 (see FIG. 4(a)). Hereinafter, at least one of the first gas, a substance having a part of the molecular structure of the first gas, and a first element contained in the first gas may be referred to as the first gas, etc. In addition, in FIGS. 4(a) to 4(c), the first gas, etc. is indicated by the letter α.

[0051] This step is preferably performed under the condition that the amount of adsorption of the first gas on the surface of the wafer 200 becomes self-limiting and the amount of adsorption of the first gas on the surface of the wafer 200 becomes unsaturated, for reasons described later. In this specification, the condition that the amount of adsorption of the gas becomes self-limiting is synonymous with the condition that the amount of adsorption of the gas becomes self-limiting or the condition that the amount of adsorption of the gas asymptotically approaches a certain value. Specifically, it refers to a condition under which the amount of adsorption of the gas can be considered to be saturated at a certain amount as the gas supply time is extended. The concept that the amount of adsorption of the gas can be considered to be saturated at a certain amount includes not only the case where the amount of adsorption of the gas is actually saturated, but also the case where the amount of adsorption of the gas is not actually saturated but will be saturated over time (in the future). In addition, the condition that the amount of adsorption of the first gas on the surface of the wafer 200 becomes unsaturated is specifically a condition under which the first gas is not adsorbed to all of the first adsorption sites on the surface of the wafer 200, and the first adsorption sites for adsorbing the second gas supplied in step B described later are left.

[0052] As the inert gas, nitrogen (N2) gas, argon (Ar) gas, helium (He) gas, neon (Ne) gas, xenon (Xe) gas, or other rare gases can be used. As the inert gas, one or more of these can be used. This also applies to each step described later.

[0053] After the first gas is adsorbed onto the surface of the wafer 200, the valve 243a is closed to stop the supply of the first gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove gaseous substances remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243e to 243g are opened to supply an inert gas into the processing chamber 201 through the nozzles 249a to 249c. The inert gas supplied from the nozzles 249a to 249c acts as a purge gas, and thereby the space in which the wafer 200 exists, i.e., the processing chamber 201, is purged (purged).

[0054] [Step B] After step A is completed, a second gas is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 after the first gas is adsorbed onto the surface thereof.

[0055] Specifically, the valve 243d is opened to allow the second gas to flow into the gas supply pipe 232d. The flow rate of the second gas is adjusted by the MFC 241d, and the second gas is supplied into the processing chamber 201 via the nozzle 249a and exhausted from the exhaust port 231a. At this time, the second gas is supplied to the wafer 200 from the side of the wafer 200 (second gas supply). At this time, the valves 243e to 243g may be opened to supply an inert gas into the processing chamber 201 via each of the nozzles 249a to 249c.

[0056] The processing conditions for supplying the second gas in this step are as follows: Treatment temperature: 20 to 700°C, preferably 200 to 600°C, more preferably 500 to 600°C Treatment pressure: 1 to 10,000 Pa, preferably 10 to 2,666 Pa, more preferably 1,000 to 2,666 Pa Second gas supply flow rate: 0.01 to 4 slm, preferably 0.3 to 1 slm Second gas supply time: 1 to 360 seconds, preferably 5 to 180 seconds Other process conditions may be the same as those used when supplying the first gas in step A. However, this step is performed under conditions that cause the amount of the second gas adsorbed onto the surface of the wafer 200 on which the first adsorption sites exist to become self-limiting.

[0057] By supplying the second gas to the wafer 200 under the above-mentioned processing conditions, at least one of the second gas, a substance having a part of the molecular structure of the second gas, and a second element contained in the second gas can be adsorbed to the places on the surface of the wafer 200 where the first gas, etc. are not adsorbed, i.e., the first adsorption sites remaining on the surface of the wafer 200. This makes it possible to form a first layer 300 having the first element and the second element on the surface of the wafer 200 (see FIG. 4(b)). Hereinafter, at least one of the second gas, a substance having a part of the molecular structure of the second gas, and the second element contained in the second gas may be referred to as the second gas, etc. In addition, in FIG. 4(b) and FIG. 4(c), the second gas, etc. are indicated by the letter β.

[0058] Here, the first gas is a gas that inhibits the second gas from adsorbing to the first adsorption site. Therefore, as shown in FIG. 4(b), the second gas, etc., is not adsorbed onto the first gas, etc., on the surface of the wafer 200. Here, in this specification, "the second gas, etc., is not adsorbed onto the first gas, etc." includes not only the case where the second gas, etc., is not adsorbed onto the first gas, etc. at all, but also the case where an extremely small amount of the second gas, etc., is adsorbed onto the first gas, etc., for example, the case where the second gas, etc., is adsorbed onto about 1% of the first gas, etc., of the first gas, etc., on the wafer 200, and preferably includes the case where the second gas, etc., is adsorbed onto 1% or less of the first gas, etc.

[0059] By carrying out steps A and B, the first gas, etc. and the second gas, etc. are adsorbed to the first adsorption sites provided on the surface of the wafer 200, and a first layer 300 containing a first element and a second element can be formed (see FIG. 4(b)). In other words, a first layer doped with the second element can be formed. Predetermined adsorption sites are formed on the surface of the first layer 300 to adsorb a third gas supplied in step C described below.

[0060] By performing steps A and B under the above-mentioned processing conditions, the amount of the first gas adsorbed on the surface of the wafer 200 can be made greater than the amount of the second gas adsorbed on the surface of the wafer 200.

[0061] This step (step B) may be performed under conditions in which the amount of the second gas adsorbed to the surface of the wafer 200 is not saturated, or may be performed under conditions in which the amount of the second gas adsorbed to the surface of the wafer 200 is saturated. Specifically, the conditions in which the amount of the second gas adsorbed to the surface of the wafer 200 is not saturated refer to conditions in which the second gas is not adsorbed to all of the first adsorption sites remaining on the surface of the wafer 200.

[0062] After the first layer 300 is formed on the surface of the wafer 200, the valve 243d is closed to stop the supply of the second gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove gaseous substances remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243e to 243g are opened to supply an inert gas into the processing chamber 201 through the nozzles 249a to 249c. The inert gas supplied from the nozzles 249a to 249c acts as a purge gas, and thereby the space in which the wafer 200 exists, i.e., the processing chamber 201, is purged (purged).

[0063] [Step C] After step B is completed, a third gas is supplied to the wafer 200 in the processing chamber 201, that is, the wafer 200 on whose surface the first layer 300 has been formed.

[0064] Specifically, the valve 243b is opened to allow the third gas to flow into the gas supply pipe 232b. The flow rate of the third gas is adjusted by the MFC 241b, and the third gas is supplied into the processing chamber 201 through the nozzle 249b and exhausted from the exhaust port 231a. At this time, the third gas is supplied to the wafer 200 from the side of the wafer 200 (third gas supply). At this time, the valves 243e to 243g may be opened to supply an inert gas into the processing chamber 201 through each of the nozzles 249a to 249c.

[0065] The processing conditions for supplying the third gas in this step are as follows: Treatment temperature: 20 to 700°C, preferably 200 to 600°C, more preferably 500 to 600°C Treatment pressure: 100 to 10,000 Pa, preferably 1,000 to 10,000 Pa Third gas supply flow rate: 0.1 to 20 slm, preferably 1 to 10 slm Third gas supply time: 1 to 120 seconds, preferably 3 to 15 seconds Other process conditions may be the same as those used when the first gas is supplied in step A.

[0066] By supplying the third gas to the wafer 200 under the above-mentioned processing conditions, the third gas and / or the third element contained in the third gas can be adsorbed to at least a portion of the first layer 300 formed on the surface of the wafer 200 (see FIG. 4(c)). In FIG. 4(c), the third gas and / or the third element contained in the third gas is indicated by the letter γ. Hereinafter, the third gas and / or the third element contained in the third gas may be referred to as the third gas, etc.

[0067] By supplying the third gas to the wafer 200 under the above-mentioned processing conditions, at least a portion of the first layer 300 formed on the surface of the wafer 200 reacts with the third gas and is modified. As a result, a second layer 400, which is a modified layer of the first layer 300 and has first adsorption sites, is formed on at least a portion of the surface of the wafer 200 (see FIG. 4(c)). The first adsorption sites formed in this step function as adsorption sites for the first gas and second gas supplied in steps A and B of the next cycle.

[0068] After the second layer 400 is formed on the surface of the wafer 200, the valve 243b is closed to stop the supply of the third gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove gaseous substances remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243e to 243g are opened to supply an inert gas into the processing chamber 201 through the nozzles 249a to 249c. The inert gas supplied from the nozzles 249a to 249c acts as a purge gas, and thereby the space in which the wafer 200 exists, i.e., the processing chamber 201, is purged (purged).

[0069] [Perform the specified number of times] The above-mentioned steps A to C are performed asynchronously, i.e., by performing the first cycle n times (n is an integer of 1 or 2 or more) in this order, a predetermined film is formed on the surface of the wafer 200. It is preferable to repeat the above-mentioned first cycle multiple times. In other words, it is preferable to make the thickness of, for example, the second layer 400 formed per cycle thinner than the desired film thickness, and to repeat the above-mentioned first cycle multiple times until the thickness of the predetermined film formed by stacking the second layer 400 reaches the desired thickness.

[0070] In this embodiment, the first gas supplied in step A may be considered to be used as an adsorption inhibitor that inhibits the above-mentioned predetermined film raw material and the second gas supplied in step B from being adsorbed to the first adsorption site and the surface of the wafer 200. The second gas supplied in step B may be considered to be used as a dopant gas that forms the above-mentioned predetermined film doped with the second element. The third gas supplied in step C may be considered to be used as a modifier that modifies the first layer 300 formed by performing steps A and B to the second layer 400.

[0071] (After purging and atmospheric pressure recovery) After the film formation process is completed, an inert gas is supplied as a purge gas from each of the nozzles 249a to 249c into the processing chamber 201 and exhausted from the exhaust port 231a. This purges the processing chamber 201, and gases and reaction by-products remaining in the processing chamber 201 are removed from the processing chamber 201 (after-purge). Thereafter, the atmosphere in the processing chamber 201 is replaced with the inert gas (inert gas replacement), and the pressure in the processing chamber 201 is returned to normal pressure (return to atmospheric pressure).

[0072] (Boat unloading and wafer discharging) Thereafter, the seal cap 219 is lowered by the boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafers 200 are carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 while being supported by the boat 217 (boat unloading). After the boat unloading, the shutter 219s is moved, and the lower end opening of the manifold 209 is sealed by the shutter 219s via the O-ring 220c (shutter close). After being carried out to the outside of the reaction tube 203, the processed wafers 200 are taken out of the boat 217 (wafer discharge).

[0073] (3) Effects of this mode According to this embodiment, in addition to the above-mentioned effects, one or more of the following effects can be obtained.

[0074] (a) After supplying the first gas in step A, the second gas is supplied in step B to make the amount of adsorption of the first gas on the surface of the wafer 200 greater than the amount of adsorption of the second gas. This makes it possible to improve the controllability of the amount of adsorption of the second gas and the uniformity of the amount of adsorption of the second gas on the surface of the wafer 200 even when the amount of adsorption of the second gas is small relative to the number of first adsorption sites at the start of step A. Furthermore, by supplying the second gas in step B under conditions in which the amount of adsorption of the second gas on the surface of the wafer 200 becomes self-limiting, it is possible to improve the controllability of the amount of adsorption of the second gas. These will be described below.

[0075] When the second gas is adsorbed to the first adsorption sites present on the surface of the wafer 200, the smaller the amount of adsorption of the second gas is relative to the number of first adsorption sites, the greater the difference between the locations where the amount of adsorption of the second gas is large and the locations where the amount of adsorption of the second gas is small. In other words, the variation in the amount of adsorption of the second gas on the surface of the wafer 200 increases. For this reason, the uniformity of the amount of adsorption of the second gas on the surface of the wafer 200 and the controllability of the amount of adsorption of the second gas are likely to decrease.

[0076] In this embodiment, after the first gas is supplied in step A, the second gas is supplied in step B, and the amount of adsorption of the first gas on the surface of the wafer 200 is made larger than the amount of adsorption of the second gas. That is, before the start of step B, the first gas is adsorbed on a relatively large number of first adsorption sites among the multiple first adsorption sites present on the surface of the wafer 200. As a result, at the start of step B, the number of first adsorption sites capable of adsorbing the second gas is reduced, so that the variation in the amount of adsorption of the second gas on the surface of the wafer 200 can be reduced. In addition, the first gas is a gas that inhibits the second gas from being adsorbed on the first adsorption site or a predetermined surface. As a result, the second gas is less likely to be adsorbed on the first gas, etc., adsorbed on the surface of the wafer 200. From the above, the second gas is more likely to be preferentially adsorbed on the first adsorption sites on the surface of the wafer 200 to which the first gas, etc., are not adsorbed. Therefore, in step B, the amount of adsorption of the second gas on the surface of the wafer 200 is less likely to exceed a desired amount. As a result, the uniformity of the amount of the second gas adsorbed on the surface of the wafer 200 can be improved.

[0077] In this embodiment, in step B, the second gas is supplied under conditions where the amount of adsorption of the second gas onto the surface of the wafer 200 is self-limiting. That is, the second gas is supplied under conditions where it can be considered that the amount of adsorption of the second gas onto the surface of the wafer 200 is saturated at a certain amount as the supply time of the second gas is extended. This makes it difficult for the amount of adsorption of the second gas onto the surface of the wafer 200 to exceed a desired amount in step B. As a result, it is possible to improve the controllability of the amount of adsorption of the second gas.

[0078] The tendency for the difference between the locations where the second gas is adsorbed in a large amount and the locations where the second gas is adsorbed in a small amount to become large when the second gas is supplied from the side of the wafer 200 in step B. The technology disclosed herein can improve the controllability of the adsorption amount of the second gas and the uniformity of the adsorption amount of the second gas on the surface of the wafer 200 even when the second gas is supplied from the side of the wafer 200.

[0079] (b) Step A is performed under conditions in which the amount of the first gas adsorbed onto the surface of the wafer 200 becomes self-limiting and the amount of the first gas adsorbed onto the surface of the wafer 200 becomes unsaturated. This makes it easier to control the number of first adsorption sites to which the first gas does not adsorb in step A. As a result, it is possible to improve the controllability of the amount of the second gas adsorbed onto a given surface.

[0080] (c) Since step B is performed under conditions where the amount of the second gas adsorbed to the surface of the wafer 200 is not saturated, step B can be performed in a shorter time than when step B is performed under conditions where the amount of the second gas adsorbed is saturated, thereby improving throughput.

[0081] (d) By performing steps A and B, the first layer 300 can be formed on the surface of the wafer 200. More specifically, by performing steps A and B, the first layer 300 that uniformly contains the first element and the second element can be formed on the surface of the wafer 200. In addition, the controllability of the amount of the second element contained in the first layer 300 can be improved.

[0082] (e) Since the second element is different from the first element, it is possible to form the first layer 300 containing the second element uniformly on the surface of the wafer 200. In addition, it is possible to improve controllability of the amount of the second element contained in the first layer 300.

[0083] (f) By performing step C, a second layer 400 can be formed on the surface of the wafer 200. More specifically, by performing step C, a film containing a first element, a second element, and a third element, in which the amount of the second element contained is well controlled, can be formed. In other words, a well-controlled amount of the second element can be added to a film mainly composed of the first element and the third element.

[0084] Here, the first element can be, for example, one or more of tungsten (W), titanium (Ti), molybdenum (Mo), tantalum (Ta), cobalt (Co), yttrium (Y), ruthenium (Ru), hafnium (Hf), zirconium (Zr), aluminum (Al), silicon (Si), boron (B), gallium (Ga), indium (In), phosphorus (P), carbon (C), etc.

[0085] For example, the third gas may be a gas containing, for example, a reducing gas, an oxidizing gas, a nitriding gas, a sulfide gas, a selenide gas, a telluride gas, or the like. The third gas may be one or more of these. For example, when the third gas is a reducing gas, a film composed of a first element and a second element may be formed on the wafer 200. For example, when the third gas is any one of an oxidizing gas, a nitriding gas, a sulfide gas, a selenide gas, and a telluride gas, an oxide film containing a first element and a second element, a nitride film containing a first element and a second element, a sulfide film containing a first element and a second element, a selenide film containing a first element and a second element, and a telluride film containing a first element and a second element may be formed on the wafer 200.

[0086] As the first gas, for example, a gas containing the first element and a halogen element as described above can be used. Examples of such a gas include hexachlorotungsten (WCl6), hexafluorotungsten (WF6), titanium tetrachloride (TiCl4), titanium tetrafluoride (TiF4), molybdenum pentachloride (MoCl5), molybdenum pentafluoride (MoF5), molybdenum dioxide dichloride (MoO2Cl2), molybdenum oxide tetrachloride (MoOCl4), tantalum pentachloride (TaCl5), tantalum pentafluoride (TaF5), cobalt difluoride (CoF2), cobalt dichloride (CoCl2), yttrium trifluoride (YF3), yttrium trichloride (YCl3), ruthenium trichloride (RuCl3), ruthenium trifluoride (RuCl4 ... Examples of the first gas that can be used include fluoride (RuF3), hafnium tetrachloride (HfCl4), hafnium tetrafluoride (HfF4), zirconium tetrachloride (ZrCl4), zirconium tetrafluoride (ZrF4), aluminum trichloride (AlCl3), aluminum trifluoride (AlF3), dichlorosilane (SiH2Cl2), 1,2-dichlorodisilane (Si2H4Cl2), 1,1,1-trichlorodisilane (Si2H3Cl3), 1,1,2-trichlorodisilane (Si2H3Cl3), pentachlorodisilane (Si2HCl5), hexachlorodisilane (Si2Cl6), and tetrafluorosilane (SiF4). As the first gas, for example, monosilane (SiH4), disilane (Si2H6), trisilane (Si3H8), tetrasilane (Si4H 10 ), boron trifluoride (BF3), boron trichloride (BCl3), gallium trifluoride (GaF3), gallium trichloride (GaCl3), indium trifluoride (InF3), indium trichloride (InCl3), phosphorus trifluoride (PF3), phosphorus pentafluoride (PF5), phosphorus trichloride (PCl3), phosphorus pentachloride (PCl5), carbon tetrafluoride (CF4), carbon tetrachloride (CCl4), trifluoromethane (CHF3), fluoromethane (CH3F), trichloromethane (CHCl3), chloromethane (CH3Cl), etc. can be used.

[0087] In addition, the first gas may be, for example, a gas having the first element as described above and an organic ligand, or a gas having the first element as described above and a hydrogen group. Examples of such gases include hexadimethylaminoditungsten (W2[N(CH3)2]6), bistertiarybutylimide bisdimethylamidotungsten ((t-C4H9NH)2W=(Nt-C4H9)2), tetrakisethylmethylaminotitanium (Ti[N(C2H5)(CH3)]4), bisethylcyclopentadienylruthenium (Ru(CH2CH3)Cp)2), biscyclopentadienylruthenium (Ru(Cp)2), tetrakisethylmethylaminohafnium (Hf[N(CH3)(CH2CH3)]4), tetrakisdiethylaminohafnium (Hf[N(CH2CH3)2]4), tetrakisdimethylaminohafnium (Hf[N(CH3)2]4), tri ... Examples of suitable fluorine-containing organic compounds include tetrakis(ethylamino)cyclopentadienyl hafnium ((Cp)Hf[N(CH3)2]3), tetrakis(ethylmethylamino)zirconium (Zr[N(CH3)Cp]4), tetrakis(diethylamino)zirconium (Zr[N(CH2CH3)2]4), tetrakis(dimethylamino)zirconium (Zr[N(CH3)2]4), tris(dimethylamino)cyclopentadienyl zirconium ((Cp)Zr[N(CH3)2]3), trimethylaluminum (Al(CH3)3), tris(dimethylamino)silane (Si[N(CH3)2]3H), boron (BH3), trimethylgallium (Ga(CH3)3), trimethylindium (In(CH3)3), phosphine (PH3), and methane (CH4).

[0088] Here, the second element may be, for example, one or more of the elements given as examples of the first element, and the second gas may be, for example, a gas containing one or more of the gases given as examples of the first gas.

[0089] The reducing gas may be, for example, one or more of hydrogen (H2) gas, deuterium (D2) gas, borane (BH3) gas, diborane (B2H6) gas, carbon monoxide (CO) gas, ammonia (NH3) gas, monosilane (SiH4) gas, disilane (Si2H6) gas, trisilane (Si3H8) gas, monogermane (GeH4) gas, digermane (Ge2H6), etc. The reactive gas may be, for example, an oxidizing gas containing oxygen (O). The oxidizing gas may be, for example, one or more of oxygen (O2), ozone (O3), water vapor (H2O), a mixed gas of H2 and O2, hydrogen peroxide (H2O2), nitrous oxide (N2O), etc. As the nitriding gas, for example, one or more of hydrogen nitride gases such as ammonia (NH3) gas, diazene (N2H2) gas, hydrazine (N2H4) gas, and N3H8 gas can be used. As the sulfurizing gas, for example, gases containing sulfane (H2S), disulfane (H2S2), diammonium sulfide ((NH4)2S), dimethyl sulfide ((CH3)2S), etc. can be used. As the sulfurizing gas, for example, one or more of these can be used. As the selenizing gas, for example, gases containing selenium (H2Se), diselane (H2Se2), dimethylselenium ((CH3)2Se), etc. can be used. As the selenizing gas, for example, one or more of these can be used. As the tellurizing gas, for example, gases containing terane (H2Te), diterane (H2Te2), dimethylselenium ((CH3)2Te), etc. can be used. As the tellurizing gas, for example, one or more of these can be used.

[0090] (4) Variations The substrate processing sequence in this embodiment can be modified as shown in the following modified examples. These modified examples can be combined as desired. Unless otherwise specified, the processing procedure and processing conditions in each step of each modified example can be the same as the processing procedure and processing conditions in each step of the substrate processing sequence described above. In the configuration of the layer (film) formed on the surface of the wafer 200 described below with reference to FIG. 5 and FIG. 6(a) to FIG. 6(c), only elements different from the layer formed on the surface of the wafer 200 described above with reference to FIG. 4(a) to FIG. 4(c) will be described below, and substantially the same elements will be denoted by the same reference numerals and their description will be omitted.

[0091] (Variation 1) As shown in the processing sequence below, a first cycle in which step A and step B are followed by step C may be performed a predetermined number of times (n1 times, n1 is an integer of 1 or 2 or more), and further a second cycle in which step A and step C are performed in the same order a predetermined number of times (n2 times, n2 is an integer of 1 or 2 or more), and a cycle in which step A and step C are performed a predetermined number of times (n3 times, n3 is an integer of 1 or 2 or more).

[0092] {(1st gas → purge → 2nd gas → purge → 3rd gas → purge) × n1 → (1st gas → purge → 3rd gas → purge) × n2} × n3

[0093] Fig. 5 shows, as an example, a layer (film) formed by performing two cycles, one each of the first cycle and the second cycle. In Fig. 5, the first cycle is indicated by the letter X, and the second cycle is indicated by the letter Y. In Fig. 5, the layer (second layer) formed by performing the first cycle is labeled with the number 400, and the layer formed by performing the second cycle is labeled with the number 500.

[0094] This modification also provides the same effects as those of the above embodiment or some of the effects thereof. In addition, in this modification, a layer 500 not including the second element is formed in addition to the second layer 400 including the second element, thereby making it possible to form a film having a low content of the second element. For example, by increasing the number of times the second cycle is performed compared to the number of times the first cycle is performed, a film having an even lower content of the second element than that of the above embodiment can be formed.

[0095] In addition, FIG. 5 shows, as an example, a case where the first adsorption sites are formed on the entire surface of the second layer 400 in step C, but is not limited thereto, and the first adsorption sites may be formed only on a part of the surface of the second layer 400. In this case, the same effect as the above-mentioned embodiment can be obtained. In this case, since the first adsorption sites are formed only on a part of the surface of the second layer 400 in step C, the number of first adsorption sites on the surface of the second layer 400 can be reduced. This makes it possible to form the first layer 300 with a lower content of the second element in the next cycle. As a result, it is possible to form a film with an even lower content of the second element.

[0096] (Variation 2) As shown in the processing sequence below, after performing steps A and B, a cycle of performing step D to remove at least a portion of the first gas adsorbed to the surface of wafer 200 may be performed a predetermined number of times (m1 times, m1 is an integer of 1 or 2 or more).

[0097] (1st gas → purge → 2nd gas → purge → 1st gas removal → purge) × m1

[0098] By performing step A and step B, the first gas, etc. and the second gas, etc. are adsorbed on the surface of the wafer 200 to form the first layer 300 (see FIG. 6(a)). Then, by performing step D, at least a part of the first gas adsorbed on the surface of the wafer 200 is removed (see FIG. 6(b)). As step D, for example, a step of removing the first gas from the wafer 200 can be performed. Examples of the removal of the first gas include raising the temperature of the wafer 200 to a temperature at which the first gas is desorbed from the wafer 200, and supplying a remover (for example, one or more of a reducing gas, an oxidizing gas, and a nitriding gas, which will be described later) to the wafer 200. Here, as the processing conditions for supplying the remover in this step, the processing conditions for supplying the third gas in step C can be used.

[0099] In addition, as shown in the processing sequence below, a cycle of performing steps A, B, and D, and further performing step E of supplying a fourth gas that has a fourth element and is different from the first gas, may be performed a predetermined number of times (m2 times, m2 is an integer of 1 or 2 or more).

[0100] (1st gas → purge → 2nd gas → purge → 1st gas removal → purge → 4th gas → purge) × m2

[0101] In this modification, the fourth element may be, for example, one or more of the elements given as examples of the first element, and the fourth gas may be, for example, a gas containing one or more of the gases given as examples of the first gas.

[0102] In step E, which is performed after step D is completed, a fourth gas supply system supplies a fourth gas to the wafer 200 in the processing chamber 201, i.e., the wafer 200 from which the first gas has been removed and the second gas has been adsorbed onto its surface.

[0103] The processing conditions for supplying the fourth gas in this step are as follows: Treatment temperature: 350 to 700°C, preferably 500 to 600°C Treatment pressure: 1 to 10,000 Pa, preferably 10 to 1,333 Pa Fourth gas supply flow rate: 0.01 to 3 slm, preferably 0.1 to 1 slm Fourth gas supply time: 10 to 120 seconds, preferably 20 to 60 seconds Inert gas supply flow rate (per gas supply pipe): 0 to 10 slm Examples include:

[0104] By supplying the fourth gas to the wafer 200 under the above-mentioned processing conditions, the fourth gas and / or the fourth element contained in the fourth gas can be adsorbed to the portions on the surface of the wafer 200 where the second gas, etc., are not adsorbed (see FIG. 6(c)). More specifically, by supplying the fourth gas to the wafer 200 under the above-mentioned processing conditions, the fourth gas, etc., can be adsorbed to the surface of the wafer 200, and a third layer 600 having the second element and the fourth element can be formed (see FIG. 6(c)). In FIG. 6(c), the fourth gas and / or the fourth element contained in the fourth gas is indicated by the letter δ. Hereinafter, the fourth gas and / or the fourth element contained in the fourth gas may be referred to as the fourth gas, etc.

[0105] This modification also provides the same effects as those of the above embodiment or some of the effects thereof. Furthermore, in this modification, by removing the first gas on the surface of the wafer 200 in step D, a layer containing the second element uniformly and not the first element can be formed on the surface of the wafer 200 (see FIG. 6(b)). Furthermore, by supplying a fourth gas in step E, a third layer 600 containing the second element and the fourth element uniformly can be formed on the surface of the wafer 200 (see FIG. 6(c)). Furthermore, the controllability of the amount of the second element contained in the third layer 600 can be improved.

[0106] (Variation 3) As in the processing sequence shown below, a cycle of steps A, B, E, and C may be performed a predetermined number of times (p1 times, p1 is an integer of 1 or 2 or more).

[0107] (1st gas → purge → 2nd gas → purge → 4th gas → purge → 3rd gas → purge) × p1

[0108] This modification also provides the same effects as the above-mentioned embodiment or some of the effects. In addition, in this modification, a layer containing a first element, a second element, a third element, and a fourth element is formed. This makes it possible to form a film containing the second element and the fourth element uniformly on the surface of the wafer 200. In other words, it is possible to add a well-controlled amount of the second element and the fourth element to a film mainly composed of the first element and the third element.

[0109] Furthermore, as in the processing sequence shown below, a cycle of performing step A, step B, and step C may be performed a predetermined number of times (p1 times, where p1 is an integer of 1 or 2 or more), and further a cycle of performing step A, step E, and step C in that order may be performed a predetermined number of times (p2 times, where p2 is an integer of 1 or 2 or more), and further a cycle of performing step A, step E, and step C in that order may be performed a predetermined number of times (p3 times, where p3 is an integer of 1 or 2 or more).

[0110] {(1st gas → purge → 2nd gas → purge → 3rd gas → purge) × p1 → (1st gas → purge → 4th gas → purge → 3rd gas → purge) × p2} × p3

[0111] In this modification, the fourth element may be, for example, one or more of the elements given as examples of the first element, and may be different from the first element and the second element. Also, the fourth gas may be, for example, a gas containing one or more of the gases given as examples of the first gas.

[0112] In this modification, the same effect as the above-mentioned embodiment or some of the effects are obtained. In addition, in this modification, a layer containing the first element, the second element, and the third element, and a layer containing the first element, the fourth element, and the third element are formed. This makes it possible to form a film containing the second element and the fourth element uniformly on the surface of the wafer 200. In other words, it is possible to add a well-controlled amount of the second element and the fourth element to a film mainly composed of the first element and the third element.

[0113] <Other Aspects of the 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.

[0114] For example, when the amount of adsorption of the second gas on the surface of the wafer 200 is set to 0.001 to 30.0% of the total amount of the adsorption of the first gas and the second gas, the variation in the amount of adsorption of the second gas on the surface of the wafer 200 tends to increase. When the amount of adsorption of the second gas is set to 0.005 to 10.0% or less of the total amount of the adsorption of the first gas and the second gas, the variation in the amount of adsorption of the second gas on the surface of the wafer 200 tends to increase. Furthermore, when the amount of adsorption of the second gas is set to 0.010 to 5.0% of the total amount of the adsorption of the first gas and the second gas, the variation in the amount of adsorption of the second gas on the surface of the wafer 200 becomes significant. Even in these cases, the technique disclosed herein can improve the controllability of the amount of adsorption of the second gas on the surface of the wafer 200.

[0115] For example, in the above-mentioned embodiment, the amount of the second gas adsorbed on the surface of the wafer 200 in step B may be controlled by the supply conditions of the first gas in step A. The supply conditions of the first gas refer to, for example, at least one of the supply flow rate of the first gas, the supply time of the first gas, the partial pressure of the first gas in the processing chamber 201 when the first gas is supplied, and the concentration of the first gas (the ratio of the first gas to the inert gas) in the processing chamber 201. In this embodiment, the same effect as in the above-mentioned embodiment can be obtained.

[0116] Fig. 7 is a graph showing the relationship between the supply time of the first gas in step A and the concentration of the second element in the film when a film containing a first element, a second element, and a third element is formed by the process sequence described in the above embodiment. The horizontal axis of the graph in Fig. 7 shows the supply time of the first gas per cycle. The vertical axis of the graph in Fig. 7 shows the concentration of the second element in the film, in units of [atomic % (at.%)].

[0117] 7, it can be seen that the concentration of the second element in the film decreases as the supply time of the first gas per cycle increases and the amount of the first gas adsorbed to the first adsorption sites increases. Thus, when step A is performed under conditions in which the amount of the first gas adsorbed to the surface of the wafer 200 is unsaturated, the amount of the second gas adsorbed to the surface of the wafer 200 in step B can be reduced by increasing the supply time of the first gas in step A.

[0118] Similarly, when the supply flow rate of the first gas is increased in step A, when the partial pressure of the first gas in the processing chamber 201 during the supply of the first gas is increased, or when the concentration of the first gas in the processing chamber 201 is increased, the amount of the first gas adsorbed to the first adsorption sites in step A increases. Therefore, in these cases, the amount of the second gas adsorbed to the surface of the wafer 200 in step B decreases. In this way, by controlling the amount of the first gas adsorbed to the first adsorption sites by the supply conditions of the first gas in step A, it is possible to control the amount of the second gas adsorbed to the surface of the wafer 200 in step B.

[0119] Furthermore, for example, in the above-mentioned embodiment, the amount of the second gas adsorbed on the surface of the wafer 200 in step B may be controlled by the supply conditions of the second gas in step B. The supply conditions of the second gas refer to, for example, at least one of the supply flow rate of the second gas, the supply time of the second gas, the partial pressure of the second gas in the processing chamber 201 during the supply of the second gas, and the concentration of the second gas (the ratio of the second gas to the inert gas) in the processing chamber 201. In this embodiment, the same effect as in the above-mentioned embodiment can be obtained.

[0120] Fig. 8 is a graph showing the relationship between the supply flow rate of the second gas in step B and the concentration of the second element in the film when a film containing a first element, a second element, and a third element is formed by the process sequence described in the above embodiment. The horizontal axis of the graph in Fig. 8 shows the supply amount of the second gas per cycle. The vertical axis of the graph in Fig. 8 shows the concentration of the second element in the film, in units of [atomic % (at.%)].

[0121] 8, it can be seen that the concentration of the second element in the film increases as the amount of the second gas supplied per cycle increases and the amount of the first gas adsorbed to the first adsorption sites increases. That is, the amount of the second gas adsorbed to the surface of the wafer 200 in step B increases as the amount of the second gas supplied in step B increases.

[0122] Similarly, when the supply flow rate of the second gas is increased in step B, when the partial pressure of the second gas in the processing chamber 201 during supply of the second gas is increased, or when the concentration of the second gas in the processing chamber 201 is increased, the amount of the second gas adsorbed to the first adsorption sites in step B increases. Therefore, in these cases, the amount of the second gas adsorbed to the surface of the wafer 200 in step B increases. In this way, by controlling the amount of the second gas adsorbed to the first adsorption sites by the supply conditions of the second gas in step B, it is possible to control the amount of the second gas adsorbed to the surface of the wafer 200 in step B.

[0123] For example, in the above-mentioned embodiment, the case where step B is performed under conditions where the amount of adsorption of the second gas on the surface of the wafer 200 is not saturated has been described as an example. However, the present disclosure is not limited to such an embodiment. For example, step B may be performed so that the second gas is adsorbed to all of the first adsorption sites to which the first gas is not adsorbed. In this embodiment, the same effect as the above-mentioned embodiment can be obtained. In this embodiment, the controllability of the amount of adsorption of the second gas can be further improved compared to the case where step B is performed under conditions where the second gas is not adsorbed.

[0124] For example, in the above embodiment, a case has been described in which step A is started before step B. However, the present disclosure is not limited to such an embodiment. For example, a part of step A may be performed simultaneously with step B, or step A may be started simultaneously with step B. In this case, the same effect as in the above embodiment can be obtained.

[0125] In general, when a hydrophilic ligand is present on the surface of the wafer 200 (when a hydrophilic adsorption site is formed), a gas having a hydrophilic ligand (a hydrophilic gas) is less likely to be adsorbed to the surface of the wafer 200. Similarly, when a hydrophobic ligand is present on the surface of the wafer 200 (when a hydrophobic adsorption site is formed), a gas having a hydrophobic ligand (a hydrophobic gas) is less likely to be adsorbed to the surface of the wafer 200. Here, the hydrophilic ligand is a ligand having an electric charge or high polarity, such as a halide (e.g., a fluoride, a chloride, a bromide, an iodide), an alkoxide group (e.g., -O(CH3), -O(CH2CH3)), an amino group (e.g., -NH2, -NH(CH3), -N(CH3)2, -NH(CH2CH3), -N(CH2CH3)2), etc. In addition, hydrophobic ligands include alkyl groups (e.g., -CH3, -CH2CH3), hydrogen groups (-H), cycloalkyl groups (e.g., -C3H5, -C4H7, -C5H9, -C6H 11 ), functional groups having a carbon ring structure, (for example, a phenyl group (-C6H5), a cyclopentadienyl group (Cp)), etc.

[0126] For this reason, for example, in step A, if the first gas adsorbed to the first adsorption site forms a hydrophilic adsorption site on the surface of the wafer 200, the second gas supplied in step B is preferably a hydrophilic gas. Also, in step A, if the first gas adsorbed to the first adsorption site forms a hydrophobic adsorption site on the surface of the wafer 200, the second gas supplied in step B is preferably a hydrophobic gas. If any of these is true, the first gas tends to inhibit the second gas, etc. from adsorbing onto the wafer 200, so that the second gas becomes even more difficult to adsorb onto the first gas, etc. adsorbed onto the surface of the wafer 200. Therefore, the second gas becomes even more easily preferentially adsorbed onto the first adsorption site on the surface of the wafer 200 to which the first gas, etc. is not adsorbed. Therefore, in step B, the amount of adsorption of the second gas onto the surface of the wafer 200 becomes even more difficult to exceed the desired amount.

[0127] Here, as the hydrophilic gas, for example, a gas having a hydrophilic ligand among those listed as examples of the first gas can be used. In addition, as the hydrophilic gas, even if it is a gas not listed as an example of the first gas, a gas having a hydrophilic ligand can be appropriately used. Similarly, as the hydrophobic gas, for example, a gas having a hydrophobic ligand among those listed as examples of the first gas can be used. As the hydrophobic gas, even if it is a gas not listed as an example of the first gas, a gas having a hydrophobic ligand can be appropriately used.

[0128] For example, in the above-mentioned embodiment, the second element contained in the second gas is an element different from the first element contained in the first gas. However, the present disclosure is not limited to such an embodiment. For example, the second element may be the same element as the first element, and the second gas may be a gas having a molecular structure different from that of the first gas. In this case, the same effect as the above-mentioned embodiment can be obtained. In this case, the first layer 300 containing the first element uniformly on the surface of the wafer 200 can be formed.

[0129] It is preferable that the recipes used for each process are prepared individually according to the process contents, and are recorded 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 contents from among the multiple recipes recorded and stored in the storage device 121c. This makes it possible to form films of various film types, composition ratios, film qualities, and film thicknesses with good reproducibility using a single substrate processing device. It is also possible to reduce the burden on the operator, and to quickly start each process while avoiding operational errors.

[0130] The above-mentioned recipes may not only be newly created, but may also be prepared by modifying an existing recipe that has already been installed in the substrate processing apparatus. 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 recipe has been recorded. Also, an existing recipe that has already been installed in the substrate processing apparatus may be directly modified by operating the input / output device 122 provided in the existing substrate processing apparatus.

[0131] In the above-mentioned embodiment, an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at a time has been described. The present disclosure is not limited to the above-mentioned embodiment, and can be suitably applied to, for example, a case where a film is formed using a single-wafer type substrate processing apparatus that processes one or several substrates at a time. In addition, in the above-mentioned embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace has been described. The present disclosure is not limited to the above-mentioned embodiment, and can be suitably applied to, for example, a case where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0132] When using these substrate processing apparatuses, each process can be performed according to the same process procedures and under the same process conditions as in the above-mentioned aspects and modifications, and the same effects as in the above-mentioned aspects and modifications can be obtained.

[0133] The above-mentioned aspects and modifications may be used in appropriate combination. The processing procedures and processing conditions in such a case may be the same as those of the above-mentioned aspects and modifications. [Explanation of symbols]

[0134] 200 wafers (substrates)

Claims

1. (a) supplying a first gas to a substrate having a predetermined surface on which first adsorption sites are present, the first gas inhibiting adsorption of a second gas to the first adsorption sites; (b) supplying the second gas to the substrate under conditions such that an amount of adsorption of the second gas onto the predetermined surface is self-limiting; (a) commences simultaneously with or prior to (b); the first gas is adsorbed to the predetermined surface in a larger amount than the second gas; A method for processing a substrate.

2. (b) controlling the amount of the second gas adsorbed on the predetermined surface by adjusting the supply conditions of the first gas in (a); The method of claim 1 .

3. (a) is performed under a condition in which the amount of the first gas adsorbed onto the predetermined surface becomes self-limiting and the amount of the first gas adsorbed onto the predetermined surface becomes unsaturated; The substrate processing method according to claim 2 .

4. (b) controlling the amount of the second gas adsorbed on the predetermined surface by adjusting the supply conditions of the second gas in (b); The method of claim 1 .

5. (b) is performed under conditions in which the amount of the second gas adsorbed onto the predetermined surface is not saturated; The method of claim 1 .

6. (b) adsorbing the second gas to all of the first adsorption sites to which the first gas has not been adsorbed; The method of claim 1 .

7. the first gas has a first element; the second gas has a second element; (a) and (b) form a first layer containing the first element and the second element on the predetermined surface; The method of claim 1 .

8. (c) forming the first adsorption site on at least a portion of the predetermined surface; performing a first cycle of (a) and (b) followed by (c) a predetermined number of times; The substrate processing method according to claim 7 .

9. The first cycle and a second cycle in which (a) and (c) are performed in this order are each performed a predetermined number of times. The substrate processing method according to claim 8 .

10. the second element is the same element as the first element, The second gas has a molecular structure different from that of the first gas. The substrate processing method according to claim 7 .

11. The second element is an element different from the first element. The substrate processing method according to claim 8 .

12. (c) supplying a third gas to the substrate to form the first adsorption site on at least a portion of the predetermined surface; The substrate processing method according to claim 8 .

13. the third gas has a third element; (c) forming a second layer containing the third element and having the first adsorption site on a surface of the second layer on at least a portion of the predetermined surface; The method of claim 12.

14. (d) removing at least a portion of the first gas adsorbed on the predetermined surface; The substrate processing method according to claim 7 .

15. (e) supplying a fourth gas having a fourth element and being different from the first gas, and forming a third layer having the second element and the fourth element on the predetermined surface; The method of claim 14.

16. In (b), the second gas is supplied from a side of the substrate. The method of claim 1 .

17. The substrate processing method according to any one of claims 1 to 16, wherein the following (1) or (2) is satisfied: (1) The first gas adsorbed to the first adsorption site forms a hydrophilic adsorption site on the predetermined surface, and the second gas is a hydrophilic gas. (2) The first gas adsorbed to the first adsorption site forms a hydrophobic adsorption site on the predetermined surface, and the second gas is a hydrophobic gas.

18. (a) supplying a first gas to a substrate having a predetermined surface on which a first adsorption site is present, the first gas inhibiting adsorption of a second gas to the predetermined surface; (b) supplying the second gas to the substrate under conditions such that an amount of adsorption of the second gas onto the predetermined surface is self-limiting; (a) commences simultaneously with or prior to (b); the first gas is adsorbed to the predetermined surface in a larger amount than the second gas; A method for manufacturing a semiconductor device.

19. a first gas supply system that supplies a first gas to a substrate having a predetermined surface on which a first adsorption site is present, the first gas inhibiting the second gas from being adsorbed to the predetermined surface; a second gas supply system that supplies the second gas to the substrate; a control unit configured to be capable of controlling the first gas supply system and the second gas supply system so that a process including (a) a process of supplying the first gas to the substrate and (b) a process of supplying the second gas is performed, the process (a) being started simultaneously with or prior to (b), and the first gas is adsorbed in a larger amount on the predetermined surface than the second gas; A substrate processing apparatus comprising:

20. (a) supplying a first gas to a substrate having a predetermined surface on which a first adsorption site is present, the first gas inhibiting adsorption of a second gas to the predetermined surface; (b) supplying the second gas to the substrate under conditions such that an amount of adsorption of the second gas onto the predetermined surface is self-limiting; (a) commences simultaneously with or prior to (b); the first gas being more highly adsorbed on the predetermined surface than the second gas; A program executed by the substrate processing apparatus.

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