Substrate processing method, method of manufacturing semiconductor device, substrate processing apparatus, and recording medium

Abstract

The invention relates to a substrate processing method, a method of manufacturing a semiconductor device, a substrate processing apparatus, and a recording medium. The present invention addresses the problem of providing a technique capable of improving the uniformity of a film formed on the surface of a substrate. The method includes: (a) a step of supplying a first gas to a substrate having a predetermined surface on which a first adsorption site is present, the first gas blocking adsorption of a second gas to the first adsorption site; and (b) a step of supplying the second gas to the substrate under the condition that the adsorption amount of the second gas to the predetermined surface becomes self-limiting, in which (a) and (b) are started at the same time or before (b), and the adsorption amount of the first gas on the predetermined surface is greater than that of the second gas.

Description

Technical Field

[0001] The present invention relates to a substrate processing method, a method for manufacturing a semiconductor device, a substrate processing apparatus and a recording medium. Background Art

[0002] As one of the steps of a substrate processing step (a step of manufacturing a semiconductor device), a step of forming a film on the surface of a substrate using a reaction inhibiting gas is sometimes performed (for example, see Patent Document 1).

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2022-110465 Summary of the invention

[0006] Problems to be solved by the invention

[0007] The present invention provides a technology capable of improving the uniformity of a film formed on a substrate surface.

[0008] Means for solving problems

[0009] According to one embodiment of the present invention, a technology is provided, which has:

[0010] (a) a process of supplying a first gas to a substrate having a specified surface having a first adsorption site, wherein the first gas is a gas that hinders the adsorption of a second gas on the first adsorption site; and (b) a process of supplying the second gas to the substrate under the condition that the amount of adsorption of the second gas on the specified surface becomes self-limiting, (a) starting simultaneously with (b) or before (b), and the amount of the first gas adsorbed on the specified surface is greater than that of the second gas.

[0011] Effects of the Invention

[0012] According to the present invention, the uniformity of a film formed on a substrate surface can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 1 is a schematic diagram of the structure of a vertical processing furnace of a substrate processing apparatus preferably used in one embodiment of the present invention, and shows a processing furnace 202 portion in a longitudinal cross-sectional view.

[0014] Figure 2 This is a schematic diagram of a vertical processing furnace of a substrate processing device preferably used in one embodiment of the present invention. Figure 1 A cross-sectional view taken along line AA shows a portion of the processing furnace 202 .

[0015] Figure 31 is a schematic diagram of the configuration of a controller 121 of a substrate processing apparatus preferably used in one embodiment of the present invention, and is a diagram showing a control system of the controller 121 in the form of a block diagram.

[0016] Figure 4 (a)~ Figure 4 (c) is a partially enlarged cross-sectional view showing an example of a substance formed in each step of the processing sequence in one embodiment of the present invention; Figure 4 (a) is a partially enlarged cross-sectional view of the surface of the wafer 200 after the first gas is adsorbed on the surface of the wafer 200; Figure 4 (b) is a partially 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 the first layer 300;

[0017] Figure 4 (c) is a partially 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 reformed into the second layer 400 by the third gas.

[0018] Figure 5 This is a partially enlarged cross-sectional view of a film formed on the surface of the wafer 200 in Modification 1 of the present invention.

[0019] Figure 6 (a)~ Figure 6 (c) is a partially enlarged cross-sectional view showing an example of a substance formed in each step of the processing sequence in Modification Example 2 of the present invention; Figure 6 (a) is a partially 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 the first layer 300; Figure 6 (b) is a partially 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; Figure 6 (c) is a partially 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 and the third layer 600 is formed.

[0020] Figure 7 This is a diagram showing the relationship between the supply time of the first gas per cycle and the concentration of the second element in the film when a film is formed using the processing sequence in one embodiment of the present invention.

[0021] Figure 8 This 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 a film is formed using the processing sequence in one embodiment of the present invention.

[0022] Description of Reference Numerals

[0023] 200 wafers (substrate) DETAILED DESCRIPTION

[0024] <One embodiment of the present invention>

[0025] The following mainly refers to Figure 1 to Figure 3 as well as Figure 4 (a)~ Figure 4 (c) of the present invention is described. It should be noted that the drawings used in the following description are schematic, and the relationship between the dimensions of the elements shown in the drawings, the ratio of the elements, etc. may not be consistent with reality. In addition, the relationship between the dimensions of the elements, the ratio of the elements, etc. may not be consistent between multiple drawings.

[0026] (1) Configuration of substrate processing apparatus

[0027] like Figure 1 As shown, the processing furnace 202 has a heater 207 as a temperature adjustment unit (heating unit). The heater 207 is cylindrical and is vertically installed by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) the gas by heat.

[0028] A reaction tube 203 is disposed concentrically with the heater 207 on the inner side of 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 into a cylindrical shape with a closed upper end and an open lower end. Below the reaction tube 203, a manifold 209 is disposed concentrically with 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 as a sealing member is provided between the manifold 209 and the reaction tube 203. The reaction tube 203 is installed vertically in the same manner as the heater 207. The reaction tube 203 and the manifold 209 mainly constitute a processing container (reaction container). A processing chamber 201 is formed in the hollow portion of the cylinder of the processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. The wafer 200 is processed in the processing chamber 201.

[0029] In the processing chamber 201, nozzles 249a to 249c as the first to third supply parts are respectively provided in a manner penetrating the side wall of the manifold 209. The nozzles 249a to 249c are also referred to as the first to third nozzles, respectively. The nozzles 249a to 249c are made of, for example, a heat-resistant material such as quartz or SiC. Gas supply pipes 232a to 232c are respectively connected to the nozzles 249a to 249c. The nozzles 249a to 249c are different nozzles, and the nozzles 249a and 249c are respectively provided adjacent to the nozzle 249b.

[0030] On the gas supply pipes 232a to 232c, mass flow controllers (MFCs) 241a to 241c as flow controllers (flow control units) and valves 243a to 243c as on-off valves are provided 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. MFCs 241d to 241g and valves 243d to 243g are provided in order from the upstream side of the gas flow on the gas supply pipes 232d to 232g.

[0031] like Figure 2 As shown, the nozzles 249a to 249c are respectively provided in a circular ring-shaped space between the inner wall of the reaction tube 203 and the wafer 200 in a manner of rising from the lower part of the inner wall of the reaction tube 203 along the upper part toward the upper side of the arrangement direction of the wafer 200. The nozzles 249a and 249c are arranged in a manner of sandwiching 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 wafer 200). The gas supply holes 250a to 250c are respectively opened in a manner of facing (facing) the exhaust port 231a in a plan view, and can supply gas toward the wafer 200. A plurality of gas supply holes 250a to 250c are provided from the lower part to the upper part of the reaction tube 203.

[0032] The first gas is supplied from the gas supply pipe 232a via the MFC 241a, the valve 243a, and the nozzle 249a into the processing chamber 201. Here, the first gas is a gas that prevents the second gas and the fourth gas described later from being adsorbed on the wafer 200, or prevents the second gas and the fourth gas from being adsorbed on the first adsorption site.

[0033] The third gas is supplied into the processing chamber 201 from the gas supply pipe 232 b via the MFC 241 b , the valve 243 b , and the nozzle 249 b .

[0034] The fourth gas is supplied into the processing chamber 201 from the gas supply pipe 232 c via the MFC 241 c , the valve 243 c , and the nozzle 249 c .

[0035] The second gas is supplied from the gas supply pipe 232 d into the processing chamber 201 via the MFC 241 d , the valve 243 d , the gas supply pipe 232 a , and the nozzle 249 a .

[0036] Inert gas is supplied from gas supply pipes 232e to 232g into the processing chamber 201 via MFCs 241e to 241g, valves 243e to 243g, gas supply pipes 232a to 232c, and nozzles 249a to 249c. The inert gas functions as a purge gas, a carrier gas, a dilution gas, and the like.

[0037] The first gas supply system is mainly composed of the gas supply pipe 232a, MFC241a, and valve 243a. The third gas supply system is mainly composed of the gas supply pipe 232b, MFC241b, and valve 243b. The fourth gas supply system is mainly composed of the gas supply pipe 232c, MFC241c, and valve 243c. The second gas supply system is mainly composed of the gas supply pipe 232d, MFC241d, and valve 243d. The inactive gas supply system is mainly composed of the gas supply pipes 232e to 232g, MFC241e to 241g, and valves 243e to 243g.

[0038] Any one or all of the above-mentioned various supply systems may also be configured as an integrated supply system 248 in which valves 243a to 243g, MFCs 241a to 241g, etc. are integrated. The integrated supply system 248 is configured to be connected to each of the gas supply pipes 232a to 232g, and the supply operation of various substances (various gases) in the gas supply pipes 232a to 232h, that is, the opening and closing operation of the valves 243a to 243g, the flow rate adjustment operation based on the MFCs 241a to 241g, etc., is controlled by the controller 121 described later. The integrated supply system 248 is configured as an integrated unit of an integral type or a split type, and can be mounted and disassembled relative to the gas supply pipes 232a to 232g, etc. as an integrated unit, and the integrated supply system 248 can be maintained, replaced, and added as an integrated unit.

[0039] An exhaust port 231a for exhausting the atmosphere in the processing chamber 201 is provided below the side wall of the reaction tube 203. Figure 2As shown, the exhaust port 231a is provided at a position opposite (facing) to the nozzles 249a to 249c (gas supply holes 250a to 250c) sandwiching the wafer 200 when viewed from above. The exhaust port 231a may also be provided along the lower part to the upper part of the side wall of the reaction tube 203, 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 regulating unit). The APC valve 244 can perform vacuum exhaust and stop vacuum exhaust in the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is in operation. The APC valve 244 is further configured to adjust the valve opening based on the pressure information detected by the pressure sensor 245 when the vacuum pump 246 is operated, thereby adjusting the pressure in the processing chamber 201. The exhaust system is mainly composed of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. It is also conceivable that the vacuum pump 246 is included in the exhaust system.

[0040] A sealing cover 219 as a furnace port cover body capable of hermetically closing the lower end opening of the manifold 209 is provided below the manifold 209. An O-ring 220b as a sealing member abutting against the lower end of the manifold 209 is provided on the upper surface of the sealing cover 219. A rotating mechanism 267 for rotating a wafer boat 217 described later is provided below the sealing cover 219. A rotating shaft 255 of the rotating mechanism 267 penetrates the sealing cover 219 and is connected to the wafer boat 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the wafer boat 217. The sealing cover 219 is configured to be lifted and lowered in the vertical direction by a wafer boat elevator 115 as a lifting mechanism provided outside the reaction tube 203. The wafer boat elevator 115 is configured as a conveying device (conveying mechanism) for carrying in and out (conveying) the wafer 200 into and out of the processing chamber 201 by lifting and lowering the sealing cover 219.

[0041] A gate 219s as a furnace cover is provided below the manifold 209, and can hermetically seal the lower end opening of the manifold 209 when the sealing cover 219 is lowered and the wafer boat 217 is carried out from the processing chamber 201. An O-ring 220c as a sealing member abutting against the lower end of the manifold 209 is provided on the upper surface of the gate 219s. The opening and closing actions (lifting and lowering actions, rotating actions, etc.) of the gate 219s are controlled by the gate opening and closing mechanism 115s.

[0042] The wafer boat 217 as a substrate support is configured to support a plurality of wafers 200, for example 25 to 200, in a horizontal posture and in a state where the centers are aligned with each other in a vertical direction and in multiple layers, that is, arranged at intervals. The wafer boat 217 is made of a heat-resistant material, such as quartz, SiC, etc. At the lower part of the wafer boat 217, a heat insulation plate 218 made of a heat-resistant material, such as quartz, SiC, etc., is supported in multiple layers. It should be noted that the expression of a numerical range such as "25 to 200 sheets" in this specification means that the lower limit and the upper limit are included in the range. Therefore, for example, "25 to 200 sheets" means "more than 25 sheets and less than 200 sheets". The same is true for other numerical ranges.

[0043] A temperature sensor 263 as a temperature detector is provided in the reaction tube 203. The temperature in the processing chamber 201 is adjusted to a desired temperature distribution by adjusting the power supply to the heater 207 based on the temperature information detected by the temperature sensor 263. The temperature sensor 263 is provided along the inner wall of the reaction tube 203.

[0044] like Figure 3 As shown, the controller 121 as a control unit (control unit) is configured as a computer having a CPU (Central Processing Unit; Central Processing Unit) 121a, a RAM (Random Access Memory; Random Access Memory) 121b, a storage device 121c, and an I / O port 121d. RAM121b, a storage device 121c, and an I / O port 121d are configured to be able to exchange data with the CPU121a via an internal bus 121e. An input and output device 122 such as a touch panel is connected to the controller 121. In addition, an external storage device 123 can be connected to the controller 121. It should be noted that the substrate processing device can be configured to have one control unit or multiple control units. That is, one control unit can be used to control the processing sequence described later, or multiple control units can be used to control the processing sequence described later. In addition, multiple control units can be configured as a control system interconnected by a wired or wireless communication network, or the control system as a whole can be used to control the processing sequence described later. When the term "control unit" is used in this specification, in addition to the case where one control unit is included, a plurality of control units may be included, and a control system composed of a plurality of control units may be included.

[0045] The storage device 121c is composed of, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc. A control program for controlling the actions of the substrate processing device, a process recipe recording the steps and conditions of the substrate processing described later, etc. are recorded and stored in a readable manner in the storage device 121c. The process recipe is a combination of the controller 121 that enables the substrate processing device to perform the various steps of the substrate processing described later and obtains a specified result, and functions as a program. Hereinafter, the process recipe, the control program, etc. are collectively referred to as a program. In addition, the process recipe is also referred to as a recipe. When the term "program" is used in this specification, sometimes only the recipe is included alone, sometimes only the control program is included alone, or sometimes both are included. RAM121b is configured as a memory area (work area) that temporarily holds programs, data, etc. read out by CPU121a.

[0046] 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, gate opening and closing mechanism 115s, etc.

[0047] The CPU 121a is configured to read a control program from the storage device 121c and execute it, and to read a recipe from the storage device 121c according to input of an operation command from the input / output device 122. The CPU 121a is configured to control, according to the contents of the read recipe, flow rate adjustment operations of various substances (various gases) by the MFCs 241a to 241g, opening and closing operations of the valves 243a to 243g, opening and closing operations of the APC valve 244 and pressure adjustment operations using the APC valve 244 by the pressure sensor 245, start and stop of the vacuum pump 246, temperature adjustment operations of the heater 207 by the temperature sensor 263, rotation of the wafer boat 217 by the rotation mechanism 267 and rotation speed adjustment operations, lifting and lowering operations of the wafer boat 217 by the wafer boat elevator 115, opening and closing operations of the gate 219s by the gate opening and closing mechanism 115s, and the like.

[0048] The controller 121 can be configured by installing the above-mentioned program recorded and stored in the external storage device 123 on a computer. The external storage device 123 includes, for example, a disk such as an HDD, an optical disk such as a CD, an optical disk such as an MO, a semiconductor memory such as a USB memory, and an SSD. The storage device 121c and the external storage device 123 are configured as a computer-readable recording medium. Hereinafter, they are collectively referred to as recording media. When the term recording medium is used in this specification, sometimes only the storage device 121c is included alone, sometimes only the external storage device 123 is included alone, or sometimes both are included. In addition, it is also possible to provide the program to the computer using a communication unit such as the Internet or a dedicated line instead of using the external storage device 123.

[0049] (2) Substrate processing step

[0050] The method of processing a substrate as one of the steps of manufacturing a semiconductor device using the substrate processing apparatus described above, that is, a processing sequence example of forming a film on a wafer 200 as a substrate, mainly using Figure 4 In the following description, the operations of the various components constituting the substrate processing apparatus are controlled by the controller 121 .

[0051] In the processing sequence of this method, there are:

[0052] (a) supplying a first gas to a wafer 200 having a predetermined surface on which a first adsorption site exists, wherein the first gas is a gas that prevents a second gas from being adsorbed to the first adsorption site; and

[0053] (b) supplying the second gas to the wafer 200 under the condition that the amount of the second gas adsorbed to the predetermined surface becomes self-limiting,

[0054] Where (a) starts at the same time as (b) or before (b),

[0055] The amount of the first gas adsorbed on the predetermined surface is greater than that of the second gas.

[0056] In addition, the following situations are described below:

[0057] The method further comprises the step of (c) forming a first adsorption site on at least a portion of a predetermined surface,

[0058] The first cycle of (a) and (b) followed by (c) is performed a predetermined number of times (n times, where n is an integer of 1 or 2 or more).

[0059] In addition, the following describes a case where the third gas is supplied to the wafer 200 in (c) to form a first adsorption site on at least a portion of a predetermined surface.

[0060] Hereinafter, a case will be described in which the first gas contains the first element, the second gas contains the second element, and the third gas contains the third element.

[0061] In this specification, for convenience, the above-mentioned processing order may be expressed as follows. The same expression is also used in the following description of the modified examples, other aspects, etc.

[0062] (1st gas→purge→2nd gas→purge→3rd gas→purge)×n

[0063] The term "wafer" used in this specification may refer to the wafer itself or to a laminate of a 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, etc. formed on the wafer. When it is stated in this specification that "a predetermined layer is formed on the wafer", it may refer to directly forming the predetermined layer on the surface of the wafer itself or to forming the predetermined layer on the layer, etc. formed on the wafer. The use of "substrate" in this specification is also synonymous with the use of "wafer".

[0064] 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 oxidant may include a gaseous substance, a liquid substance such as a mist substance, or both.

[0065] The term "layer" used in this specification 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.

[0066] In the present specification, when describing the adsorption and reaction of the first gas, the second gas, the third gas and the fourth gas on the surface of the chip 200, it not only includes the manner in which they adsorb and react on the surface of the chip in an undecomposed state, but also includes the manner in which intermediates generated by their decomposition and the separation of their ligands adsorb and react on the surface of the chip 200.

[0067] (Wafer filling and wafer boat loading)

[0068] When a plurality of wafers 200 are loaded (wafer filling) into the wafer boat 217, the gate 219s is moved by the gate opening and closing mechanism 115s, and the lower end opening of the manifold 209 is opened (gate opening). Figure 1As shown, the wafer boat 217 supporting a plurality of wafers 200 is lifted by the wafer boat elevator 115 and carried into the processing chamber 201 (wafer boat loading). In this state, the sealing cap 219 is in a state of sealing the lower end of the manifold 209 via the O-ring 220b. In this way, the wafers 200 are prepared (provided) in the processing chamber 201.

[0069] It should be noted that the wafer 200 filled in the wafer boat 217 has a predetermined surface having a first adsorption site. In this embodiment, as an example, a case where the first adsorption site exists on the predetermined surface of the wafer 200 is described. It should be noted that the wafer 200 may also have a surface where a material different from the material constituting the predetermined surface is exposed.

[0070] (Pressure regulation and temperature regulation)

[0071] After the wafer boat is loaded, vacuum exhaust (decompression exhaust) is performed by the vacuum pump 246 so that the space in the processing chamber 201, that is, the space where the wafer 200 is located, becomes the desired pressure (vacuum degree). At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 244 is feedback-controlled based on the measured pressure information. In addition, the wafer 200 in the processing chamber 201 is heated by the heater 207 so that it becomes the desired processing temperature. At this time, the power supply status to the heater 207 is feedback-controlled based on the temperature information detected by the temperature sensor 263 so that the temperature distribution in the processing chamber 201 becomes the desired temperature distribution. In addition, the rotation of the wafer 200 by the rotation mechanism 267 is started. The exhaust in the processing chamber 201, the heating and rotation of the wafer 200 are all continuously performed at least until the processing of the wafer 200 is completed.

[0072] (Film forming treatment)

[0073] After that, execute the following steps A, B, and C in sequence.

[0074] [Step A]

[0075] In this step, the first gas is supplied to the wafer 200 in the processing chamber 201 .

[0076] Specifically, the valve 243a is opened to allow the first gas to flow into the gas supply pipe 232a. The first gas is flow-regulated by the MFC 241a, 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 inert gas into the processing chamber 201 through each of the nozzles 249a to 249c.

[0077] As the processing conditions when the first gas is supplied in this step, the following can be exemplified:

[0078] Processing temperature: 350-700°C, preferably 500-600°C

[0079] Processing pressure: 1-10000Pa, preferably 10-1333Pa

[0080] First gas supply flow rate: 0.01 to 3 slm, preferably 0.1 to 1 slm

[0081] First gas supply time: 10 to 120 seconds, preferably 20 to 60 seconds

[0082] Inert gas supply flow rate (per gas supply pipe): 0~10slm

[0083] The processing temperature in this specification refers to the temperature of the wafer 200 or the temperature in the processing chamber 201, and the processing pressure refers to the pressure in the processing chamber 201, in other words, the pressure of the space where the wafer 200 exists. In addition, when the supply flow rate includes 0 slm, 0 slm means that the gas (substance) is not supplied. This is also the same in the following description.

[0084] 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 on the first adsorption site existing on the surface of the wafer 200 (see Figure 4 (a) in the above). Hereinafter, the first gas, a substance having a part of the molecular structure of the first gas, at least one of the first elements contained in the first gas may be referred to as the first gas. Figure 4 (a)~ Figure 4 In (c) of FIG. 1 , the first gas and the like are represented by the letter α.

[0085] For reasons described later, 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. 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 gradually approaches a certain constant value. Specifically, it refers to the condition that the amount of adsorption of the gas is considered to be saturated at a certain amount if the supply time of the gas is extended. The concept of considering that the amount of adsorption of the gas is saturated at a certain amount does not only include the case where the amount of adsorption of the gas is actually saturated, but also includes the concept of including the case where saturation occurs over time (in the future) although saturation does not actually occur. In addition, the condition that the amount of adsorption of the first gas on the surface of the wafer 200 becomes unsaturated specifically refers to the condition that the first gas is not adsorbed on all the first adsorption sites on the surface of the wafer 200, and the first adsorption sites of the second gas supplied in the later-described step B are left.

[0086] As the inert gas, rare gases such as nitrogen (N2), argon (Ar), helium (He), neon (Ne), and xenon (Xe) can be used. As the inert gas, one or more of them can be used. This is also the same in each step described later.

[0087] After the first gas is adsorbed on 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 the gaseous substances and the like remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243e to 243g are opened to supply the inert gas into the processing chamber 201 through the nozzles 249a to 249c. The inert gas supplied from the nozzles 249a to 249c functions as a purge gas, thereby purging the space where the wafer 200 is present, that is, the processing chamber 201.

[0088] [Step B]

[0089] After step A is completed, the second gas is supplied to the wafer 200 in the processing chamber 201 , that is, the wafer 200 on the surface of which the first gas is adsorbed.

[0090] Specifically, the valve 243d is opened to allow the second gas to flow into the gas supply pipe 232d. The second gas is flow-regulated by the MFC 241d, supplied into the processing chamber 201 through 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 inert gas into the processing chamber 201 through each of the nozzles 249a to 249c.

[0091] As the processing conditions when the second gas is supplied in this step, the following can be exemplified:

[0092] Treatment temperature: 20-700°C, preferably 200-600°C, more preferably 500-600°C Treatment pressure: 1-10000 Pa, preferably 10-2666 Pa, more preferably 1000-2666 Pa

[0093] Second gas supply flow rate: 0.01 to 4 slm, preferably 0.3 to 1 slm

[0094] Second gas supply time: 1 to 360 seconds, preferably 5 to 180 seconds.

[0095] The other processing conditions may be the same as those when the first gas is supplied in step A. However, this step is performed under the condition that the amount of the second gas adsorbed onto the surface of the wafer 200 where the first adsorption site exists becomes self-limiting.

[0096] 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 the second element contained in the second gas can be adsorbed on the portion of the surface of the wafer 200 where the first gas is not adsorbed, that is, the first adsorption site remaining on the surface of the wafer 200. As a result, a first layer 300 having the first element and the second element can be formed on the surface of the wafer 200 (see Figure 4 (b) in the above). Hereinafter, the second gas, a substance having a part of the molecular structure of the second gas, at least one of the second elements contained in the second gas may be referred to as the second gas. Figure 4 (b) and Figure 4 In (c), the second gas and the like are represented by the letter β.

[0097] Here, the first gas is a gas that prevents the second gas from being adsorbed on the first adsorption site. Figure 4 As shown in (b) in FIG. 2 , the second gas, etc. is not adsorbed on the first gas, etc. on the surface of the wafer 200. Here, in this specification, the so-called "the second gas, etc. is not adsorbed on the first gas, etc." includes not only the case where the second gas, etc. is not adsorbed on the first gas, etc. at all, but also the case where a very small amount of the second gas, etc. is adsorbed on the first gas, etc., for example, the case where the second gas, etc. is adsorbed on about 1% of the first gas, etc. on the wafer 200, and preferably the case where the second gas, etc. is adsorbed on less than 1% of the first gas, etc.

[0098] By performing step A and step B, the first gas and the second gas are adsorbed on the first adsorption site provided on the surface of the wafer 200, thereby forming a first layer 300 including the first element and the second element (see Figure 4 In other words, a first layer to which the second element is added (doped) can be formed. A predetermined adsorption site for adsorbing the third gas supplied in step C described later is formed on the surface of the first layer 300 .

[0099] By performing step A and step B under the above-mentioned processing conditions, the amount of the first gas adsorbed on the surface of the wafer 200 can be made larger than the amount of the second gas adsorbed on the surface of the wafer 200 .

[0100] This step (step B) can be performed under the condition that the amount of adsorption of the second gas on the surface of the wafer 200 is not saturated, or can be performed under the condition that it is saturated. It should be noted that the condition that the amount of adsorption of the second gas on the surface of the wafer 200 is not saturated refers to all conditions that do not allow the second gas to be adsorbed on the adsorption sites remaining on the surface of the wafer 200.

[0101] 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 the gaseous substances and the like remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243e to 243g are opened to supply the inert gas into the processing chamber 201 through the nozzles 249a to 249c. The inert gas supplied from the nozzles 249a to 249c functions as a purge gas, thereby purging the space where the wafer 200 is present, that is, the processing chamber 201.

[0102] [Step C]

[0103] After step B is completed, the third gas is supplied to the wafer 200 in the processing chamber 201 , that is, the wafer 200 after the first layer 300 is formed on the surface thereof.

[0104] Specifically, the valve 243b is opened to allow the third gas to flow into the gas supply pipe 232b. The third gas is flow-regulated by the MFC 241b, 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 inert gas into the processing chamber 201 through each of the nozzles 249a to 249c.

[0105] As the processing conditions when the third gas is supplied in this step, the following can be exemplified:

[0106] Treatment temperature: 20-700°C, preferably 200-600°C, more preferably 500-600°C Treatment pressure: 100-10000 Pa, preferably 1000-10000 Pa

[0107] Third gas supply flow rate: 0.1 to 20 slm, preferably 1 to 10 slm

[0108] Third gas supply time: 1 to 120 seconds, preferably 3 to 15 seconds.

[0109] The other processing conditions can be the same as those in step A when the first gas is supplied.

[0110] 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 on at least a portion of the first layer 300 formed on the surface of the wafer 200 (see Figure 4 (c) in ). It should be noted that Figure 4 In (c), the third gas and / or the third element contained in the third gas is represented 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 or the like.

[0111] 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 having a first adsorption site as a modified layer of the first layer 300 is formed on at least a portion of the surface of the wafer 200 (see Figure 4 (c) in the above). The first adsorption site formed in this step functions as an adsorption site for the first gas and the second gas supplied in step A and step B of the next cycle.

[0112] 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 the gaseous substances and the like remaining in the processing chamber 201 from the processing chamber 201. At this time, the valves 243e to 243g are opened to supply the inert gas into the processing chamber 201 through the nozzles 249a to 249c. The inert gas supplied from the nozzles 249a to 249c functions as a purge gas, thereby purging the space where the wafer 200 is present, that is, the processing chamber 201.

[0113] [Number of times of implementation]

[0114] By performing the first cycle of the above steps A to C in a non-simultaneous, i.e., asynchronous, order n times (n is an integer greater than 1 or 2), a predetermined film is formed on the surface of the wafer 200. The above first cycle is preferably repeated a plurality of times. That is, it is preferred that the thickness of, for example, the second layer 400 formed in each cycle is made thinner than the desired film thickness, and the above first cycle is repeated a plurality of times until the thickness of the predetermined film formed by laminating the second layer 400 reaches the desired thickness.

[0115] In this embodiment, the first gas supplied in step A may be regarded as an adsorption inhibitor that inhibits the adsorption of the raw material of the above-mentioned predetermined film and the second gas supplied in step B to the first adsorption site and the surface of the wafer 200. The second gas supplied in step B may be regarded as a dopant gas for forming the above-mentioned predetermined film doped with the second element. The third gas supplied in step C may be regarded as a modifier for modifying the first layer 300 formed by performing steps A and B into the second layer 400.

[0116] (Post-purge and atmospheric pressure recovery)

[0117] After the film forming process is completed, an inert gas is supplied from each of the nozzles 249a to 249c as a purge gas into the process chamber 201, and the gas is exhausted from the exhaust port 231a. Thus, the process chamber 201 is purged, and the gas remaining in the process chamber 201, the reaction by-products, etc. are removed from the process chamber 201 (post-purge). Then, 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 restored to normal pressure (atmospheric pressure recovery).

[0118] (Wafer boat unloading and wafer removal)

[0119] After that, the sealing cover 219 is lowered by the wafer boat elevator 115, and the lower end of the manifold 209 is opened. Then, the processed wafer 200 is carried out from the lower end of the manifold 209 to the outside of the reaction tube 203 while being supported by the wafer boat 217 (wafer boat unloading). After the wafer boat is unloaded, the gate 219s is moved, and the lower end opening of the manifold 209 is sealed by the gate 219s via the O-ring 220c (gate closing). After the processed wafer 200 is carried out to the outside of the reaction tube 203, it is taken out from the wafer boat 217 (wafer taking out).

[0120] (3) Effects of this method

[0121] According to this aspect, in addition to the above-described effects, one or more of the following effects can be obtained.

[0122] (a) After the first gas is supplied in step A, the second gas is supplied in step B so that the amount of the first gas adsorbed on the surface of the wafer 200 is greater than the amount of the second gas adsorbed. Thus, even when the amount of the second gas adsorbed is small relative to the number of the first adsorption sites at the start of step A, the controllability of the amount of the second gas adsorbed and the uniformity of the amount of the second gas adsorbed on the surface of the wafer 200 can be improved. In addition, in step B, the controllability of the amount of the second gas adsorbed can be improved by supplying the second gas under the condition that the amount of the second gas adsorbed on the surface of the wafer 200 becomes self-limited. This will be described below.

[0123] When the second gas is adsorbed on the first adsorption sites existing on the surface of the wafer 200, the more the amount of the second gas adsorbed is reduced relative to the number of the first adsorption sites, the greater the difference between the site where the amount of the second gas adsorbed is large and the site where the amount of the second gas adsorbed is small tends to become. That is, the deviation of the amount of the second gas adsorbed on the surface of the wafer 200 becomes large. Therefore, the uniformity of the amount of the second gas adsorbed on the surface of the wafer 200 and the controllability of the amount of the second gas adsorbed are likely to be reduced.

[0124] In this embodiment, after the first gas is supplied in step A, the second gas is supplied in step B, and the amount of the first gas adsorbed on the surface of the wafer 200 is made greater than the amount of the second gas adsorbed. That is, before starting step B, the first gas is adsorbed on a relatively large number of the first adsorption sites among the plurality of first adsorption sites on the surface of the wafer 200. As a result, when step B starts, the number of first adsorption sites to which the second gas can be adsorbed decreases, and thus the variation in the amount of the second gas adsorbed on the surface of the wafer 200 can be reduced. In addition, the first gas is a gas that prevents the second gas from being adsorbed on the first adsorption site or on a predetermined surface. As a result, the second gas becomes less likely to be adsorbed on the first gas adsorbed on the surface of the wafer 200. As can be seen from the above, the second gas becomes more likely to be preferentially adsorbed on the first adsorption site on the surface of the wafer 200 to which the first gas is not adsorbed. Therefore, in step B, the amount of the second gas adsorbed on the surface of the wafer 200 can be made 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.

[0125] In addition, in the present embodiment, in step B, the second gas is supplied under the condition that the amount of the second gas adsorbed onto the surface of the wafer 200 becomes self-limiting. That is, the second gas is supplied under the condition that the amount of the second gas adsorbed onto the surface of the wafer 200 is considered to be saturated at a certain amount as the supply time of the second gas increases. Thus, in step B, the amount of the second gas adsorbed onto the surface of the wafer 200 can be made less likely to exceed a desired amount. As a result, the controllability of the amount of the second gas adsorbed can be improved.

[0126] It should be noted that the tendency for the difference between the portion with a large amount of the second gas adsorbed and the portion with a small amount of the second gas adsorbed to become large when the second gas is adsorbed on the first adsorption site described above becomes significant when the second gas is supplied from the side of the wafer 200 in step B. The technology of the present invention 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.

[0127] (b) Step A is performed under the condition that 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. Thus, in step A, it becomes easy to control the number of first adsorption sites where the first gas is not adsorbed. As a result, the controllability of the amount of the second gas adsorbed onto the predetermined surface can be improved.

[0128] (c) By performing step B under the condition that the amount of the second gas adsorbed on the surface of the wafer 200 is not saturated, step B can be performed in a shorter time than when the amount of the second gas adsorbed is saturated. This can improve productivity.

[0129] (d) By performing step A and step B, the first layer 300 can be formed on the surface of the wafer 200. More specifically, by performing step A and step B, the first layer 300 uniformly containing 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.

[0130] (e) By making the second element different from the first element, the first layer 300 containing the second element can be uniformly 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.

[0131] (f) By performing step C, the second layer 400 can be formed on the surface of the wafer 200. More specifically, by performing step C, a film containing the first element, the second element, and the third element in which the amount of the second element contained is sufficiently controlled can be formed. In other words, a sufficiently controlled amount of the second element can be added to a film mainly composed of the first element and the third element.

[0132] Here, as the first element, 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. can be used.

[0133] For example, as the third gas, a gas including a reducing gas, an oxidizing gas, a nitriding gas, a sulfiding gas, a seleniding gas, a telluriding gas, etc. can be used. As the third gas, one or more of them can be used. For example, when the third gas is a reducing gas, a film composed of the first element and the second element can be formed on the wafer 200. For example, when the third gas is any one of an oxidizing gas, a nitriding gas, a sulfiding gas, a seleniding gas, and a telluriding gas, an oxide film including the first element and the second element, a nitride film including the first element and the second element, a sulfide film including the first element and the second element, a seleniding film including the first element and the second element, and a telluriding film including the first element and the second element can be formed on the wafer 200.

[0134] As the first gas, for example, a gas containing the first element and a halogen element as described above can be used. As such a gas, for example, tungsten hexachloride (WCl6), tungsten hexafluoride (WF6), titanium tetrachloride (TiCl4), titanium tetrafluoride (TiF4), molybdenum pentachloride (MoCl5), molybdenum pentafluoride (MoF5), molybdenum dichloride dioxide (MoO2Cl2), molybdenum tetrachloride oxide (MoOCl4), tantalum pentachloride (TaCl5), tantalum pentafluoride (TaF5), cobalt difluoride (CoF2), cobalt dichloride (CoCl2), yttrium trifluoride (YF3), yttrium trichloride (YCl3), ruthenium trichloride (RuCl3), ruthenium trifluoride (RuF5), and tungsten trichloride (TFA). (RuF3), hafnium tetrachloride (HfCl4), hafnium tetrafluoride (HfF4), zirconium tetrachloride (ZrCl4), zirconium tetrafluoride (ZrF4), aluminum trichloride (AlCl3), aluminum trifluoride (AlF3), dichlorosilane (SiH2Cl2), 1,2-dichlorosilane (Si2H4Cl2), 1,1,1-trichlorodisilane (Si2H3Cl3), 1,1,2-trichlorodisilane (Si2H3Cl3), pentachlorodisilane (Si2HCl5), hexachlorodisilane (Si2Cl6), tetrafluorosilane (SiF4), etc. In addition, as the first gas, for example, monosilane (SiH4), disilane (Si2H6), trisilane (Si3H8), butasilane (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), chloroform (CHCl3), chloromethane (CH3Cl), etc.

[0135] In addition, as the first gas, for example, a gas having the first element and an organic ligand as described above, or a gas having the first element and a hydrogen group as described above can be used. As such a gas, for example, hexakidimethylamidoditungsten (W2[N(CH3)2]6), bis-tert-butylimide bisdimethylamidotungsten ((t-C4H9NH)2W=(Nt-C4H9)2), tetraethylmethylamidotitanium (Ti[N(C2H5)(CH3)]4), bisethylcyclopentadienylruthenium (Ru(CH2CH3)Cp)2), biscyclopentadienylruthenium (Ru(Cp)2), tetraethylmethylamidohafnium (Hf[N(CH3)(CH2CH3)]4), tetrakisdiethylamidohafnium (Hf[N(CH2CH3)2]4), tetrakisdimethylamidohafnium (Hf[N(CH3)2]4), Trisdimethylaminocyclopentadienyl hafnium ((Cp)Hf[N(CH3)2]3), tetraethylmethylaminozirconium (Zr[N(CH3)Cp]4), tetrakisdiethylaminozirconium (Zr[N(CH2CH3)2]4), tetrakisdimethylaminozirconium (Zr[N(CH3)2]4), trisdimethylaminocyclopentadienyl zirconium ((Cp)Zr[N(CH3)2]3), trimethylaluminum (Al(CH3)3), trisdimethylaminosilane (Si[N(CH3)2]3H), borane (BH3), trimethylgallium (Ga(CH3)3), trimethylindium (In(CH3)3), phosphine (PH3), methane (CH4), etc.

[0136] Here, as the second element, for example, one or more of the elements cited as examples of the first element may be used. Also, as the second gas, for example, a gas containing one or more of the gases cited as examples of the first gas may be used.

[0137] As the reducing gas, for example, one or more of the following gases can be used: 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, germane (GeH4) gas, digermane (Ge2H6) gas, etc. In addition, as the reaction gas, for example, an oxidizing gas containing oxygen (O) gas can be used. As the oxidizing gas, for example, one or more of the following gases can be used: 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 the following hydrogen nitride-based gases can be used: ammonia (NH3) gas, diazine (N2H2) gas, hydrazine (N2H4) gas, N3H8 gas, etc. As the sulfiding gas, for example, gases containing sulfane (H2S), disulfane (H2S2), diammonium sulfide ((NH4)2S), dimethyl sulfide ((CH3)2S), etc. can be used. As the sulfiding gas, one or more of them can be used. As the selenization gas, for example, gases containing hydrogen selenide (H2Se), hydrogen diselenide (H2Se2), dimethyl selenium ((CH3)2Se), etc. can be used. As the selenization gas, one or more of them can be used. As the telluride gas, for example, gases containing hydrogen telluride (H2Te), hydrogen ditelluride (H2Te2), dimethyl tellurium ((CH3)2Te), etc. can be used. As the telluride gas, one or more of them can be used.

[0138] (4) Modification

[0139] The substrate processing sequence in this method can be changed as shown in the following modified examples. These modified examples can be combined arbitrarily. Unless otherwise specified, the processing steps and processing conditions in each step of each modified example can be set to be the same as the processing steps and processing conditions in each step of the above-mentioned substrate processing sequence. Figure 5 and Figure 6 (a)~ Figure 6 In the structure of the layer (film) formed on the surface of the wafer 200 described in (c), only the above Figure 4 (a)~ Figure 4 Different elements in the layer formed on the surface of the wafer 200 described in (c) will be described, and substantially the same elements are denoted by the same reference numerals and their description will be omitted.

[0140] (Variant 1)

[0141] As shown in the processing order below, the first cycle of performing step C after step A and step B can be performed a specified number of times (n1 times, n1 is an integer greater than 1 or 2), and then the second cycle of performing the specified number of times (n2 times, n2 is an integer greater than 1 or 2) can be performed a specified number of times (n3 times, n3 is an integer greater than 1 or 2), wherein the second cycle is a cycle of performing steps A and C in sequence.

[0142] {(first gas→purge→second gas→purge→third gas→purge)×n1→(first gas→purge→third gas→purge)×n2}×n3

[0143] As an example, Figure 5 The following shows a layer (film) formed by performing the following cycle twice, in which the first cycle and the second cycle are performed one by one. Figure 5 In the example, the first cycle is represented by the letter X, and the second cycle is represented by the letter Y. Figure 5 In FIG. 1 , a layer (second layer) formed by performing the first cycle is denoted by 400, and a layer formed by performing the second cycle is denoted by 500.

[0144] In this modification, the same effect as the above-mentioned method or a part of the effect can be obtained. In addition, in this modification, in addition to the second layer 400 containing the second element, a layer 500 not containing the second element is formed, thereby forming a film with a small content of the second element. For example, if the number of times the second cycle is performed is increased relative to the number of times the first cycle is performed, a film with a smaller content of the second element than the above-mentioned method can be formed.

[0145] It should be noted that in Figure 5 In the embodiment, as an example, the case where the first adsorption site is formed on the entire surface of the second layer 400 in step C is shown, but the present invention is not limited thereto, and the first adsorption site may be formed only on a portion 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 site is formed only on a portion of the surface of the second layer 400 in step C, the number of the first adsorption sites on the surface of the second layer 400 can be reduced. As a result, in the next cycle, the first layer 300 having a lower content of the second element can be formed. As a result, a film having a lower content of the second element can be formed.

[0146] (Variant 2)

[0147] As in the processing sequence shown below, after performing steps A and B, step D of removing at least a portion of the first gas adsorbed on the surface of the chip 200 may be cycled a predetermined number of times (m1 times, where m1 is an integer greater than 1 or 2).

[0148] (1st gas → purge → 2nd gas → purge → remove 1st gas → purge) × m1

[0149] By performing step A and step B, the first gas and the second gas are adsorbed on the surface of the wafer 200 to form the first layer 300 (see Figure 6 Then, by performing step D, at least a portion of the first gas adsorbed on the surface of the wafer 200 is removed (see Figure 6 (b) in step D). For example, a step of removing the first gas may be performed on the wafer 200. As the removal of the first gas, for example, the wafer 200 is heated to a temperature at which the first gas is separated from the wafer 200; and a removing agent (for example, one or more of the reducing gas, oxidizing gas, and nitriding gas described later) is supplied to the wafer 200. Here, as the processing conditions when the removing agent is supplied in this step, the processing conditions when the third gas is supplied in step C can be used.

[0150] In addition, the following cycle can be performed a specified number of times (m2 times, m2 is an integer greater than 1 or 2) as in the processing order shown below, in which step A, step B and step D are performed, and then step E is performed to supply a fourth gas which is a gas having a fourth element and different from the first gas.

[0151] (1st gas → purge → 2nd gas → purge → remove 1st gas → purge → 4th gas → purge) × m2

[0152] Here, in this modification, as the fourth element, for example, one or more of the elements cited as examples of the first element can be used. Also, as the fourth gas, for example, a gas containing one or more of the gases cited as examples of the first gas can be used.

[0153] In step E performed after step D, the fourth gas supply system supplies the fourth gas to the wafer 200 in the processing chamber 201 , that is, the wafer 200 from which the first gas has been removed and on which the second gas is adsorbed.

[0154] As the processing conditions when the fourth gas is supplied in this step, the following can be exemplified:

[0155] Processing temperature: 350-700°C, preferably 500-600°C

[0156] Processing pressure: 1-10000Pa, preferably 10-1333Pa

[0157] Fourth gas supply flow rate: 0.01 to 3 slm, preferably 0.1 to 1 slm

[0158] 4th gas supply time: 10 to 120 seconds, preferably 20 to 60 seconds

[0159] Inert gas supply flow rate (per gas supply pipe): 0~10slm

[0160] 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 on the surface of the wafer 200 where the second gas or the like is not adsorbed (see Figure 6 In more detail, by supplying the fourth gas to the wafer 200 under the above-mentioned processing conditions, the fourth gas can be adsorbed on the surface of the wafer 200 to form a third layer 600 having the second element and the fourth element (see Figure 6 (c) in ). It should be noted that Figure 6 In (c) of FIG. 1 , the fourth gas and / or the fourth element contained in the fourth gas is represented 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 or the like.

[0161] In this modification, the same effect as in the above method or a part of the effect can be obtained. In addition, in this modification, by further removing the first gas on the surface of the wafer 200 in step D, a layer uniformly containing the second element and not containing the first element can be formed on the surface of the wafer 200 (see Figure 6 Furthermore, by supplying the fourth gas in step E, a third layer 600 uniformly containing the second element and the fourth element can be formed on the surface of the wafer 200 (see Figure 6 In addition, the controllability of the amount of the second element contained in the third layer 600 can be improved.

[0162] (Variant 3)

[0163] As in the processing sequence shown below, a loop of step A, step B, step E, and step C may be performed a predetermined number of times (p1 times, where p1 is an integer greater than or equal to 1 or 2).

[0164] (1st gas → purge → 2nd gas → purge → 4th gas → purge → 3rd gas → purge) × p1

[0165] In this modification, the same effect as in the above-mentioned method or a part of the effect can also be obtained. In addition, in this modification, a layer comprising the first element, the second element, the third element and the fourth element is formed. Thus, a film uniformly comprising the second element and the fourth element can be formed on the surface of the wafer 200. In other words, the second element and the fourth element of a fully controlled amount can be added to the film mainly composed of the first element and the third element.

[0166] In addition, as in the processing order shown below, a loop of step A, step B and step C may be performed a prescribed number of times (p1 times, p1 is an integer greater than 1 or 2), and then a loop of step A, step E and step C may be performed a prescribed number of times (p2 times, p2 is an integer greater than 1 or 2) in sequence.

[0167] {(1st gas→purge→2nd gas→purge→3rd gas→purge)×p1→(1st gas→purge→4th gas→purge→3rd gas→purge)×p2}×p3

[0168] Here, in this modification, as the fourth element, for example, one or more of the elements cited as examples of the first element and an element different from the first element and the second element is used. In addition, as the fourth gas, for example, a gas containing one or more of the gases cited as examples of the first gas can be used.

[0169] In this modification, the same effect as in the above-mentioned method or a part of the effect can also be obtained. In addition, in this modification, a layer comprising the first element, the second element and the third element and a layer comprising the first element, the fourth element and the third element are formed respectively. Thus, a film uniformly comprising the second element and the fourth element can be formed on the surface of the wafer 200. In other words, the second element and the fourth element of a fully controlled amount can be added to the film mainly composed of the first element and the third element.

[0170] <Other aspects of the present invention>

[0171] The embodiments of the present invention have been specifically described above. However, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the gist of the present invention.

[0172] For example, when the amount of the second gas adsorbed on the surface of the wafer 200 is set to 0.001 to 30.0% of the total amount of the amount of the first gas adsorbed and the amount of the second gas adsorbed, the deviation of the amount of the second gas adsorbed on the surface of the wafer 200 is likely to become large. In addition, when the amount of the second gas adsorbed is set to less than 0.005 to 10.0% of the total amount of the amount of the first gas adsorbed and the amount of the second gas adsorbed, the deviation of the amount of the second gas adsorbed on the surface of the wafer 200 is likely to become large. Furthermore, when the amount of the second gas adsorbed is set to 0.010 to 5.0% of the total amount of the amount of the first gas adsorbed and the amount of the second gas adsorbed, the deviation of the amount of the second gas adsorbed on the surface of the wafer 200 becomes significant. In these cases, the controllability of the amount of the second gas adsorbed on the surface of the wafer 200 can also be improved by the technology of the present invention.

[0173] For example, in the above-described method, the amount of the second gas adsorbed on the surface of the wafer 200 in step B can also be controlled by the supply condition of the first gas in step A. The supply condition of the first gas refers 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, or the concentration of the first gas in the processing chamber 201 (the ratio of the first gas to the inert gas). In this method, the same effect as in the above-described method can be obtained.

[0174] Figure 7 This is a diagram 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 including the first element, the second element, and the third element is formed by the processing sequence described in the above embodiment. Figure 7 The horizontal axis of the graph represents the supply time of the first gas per cycle. Figure 7 The vertical axis of the graph represents the concentration of the second element in the film, and the unit is [atomic % (at. %)].

[0175] Depend on Figure 7 It can be seen that the longer the supply time of the first gas per cycle is, the more the amount of the first gas adsorbed on the first adsorption site increases, and the lower the concentration of the second element in the film. Therefore, when step A is performed under the condition that the amount of the first gas adsorbed on the surface of the wafer 200 becomes unsaturated, the longer the supply time of the first gas in step A is extended, the more the amount of the second gas adsorbed on the surface of the wafer 200 in step B can be reduced.

[0176] 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 is increased when the first gas is supplied, or when the concentration of the first gas in the processing chamber 201 is increased, the amount of the first gas adsorbed on the first adsorption site in step A increases. Therefore, in these cases, the amount of the second gas adsorbed on the surface of the wafer 200 in step B decreases. In this way, by controlling the amount of the first gas adsorbed on the first adsorption site according to the supply conditions of the first gas in step A, the amount of the second gas adsorbed on the surface of the wafer 200 in step B can be controlled.

[0177] In addition, for example, in the above-described method, the amount of the second gas adsorbed on the surface of the wafer 200 in step B may be controlled according to 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 when the second gas is supplied, or the concentration of the second gas in the processing chamber 201 (the ratio of the second gas to the inert gas). In this method, the same effect as in the above-described method can be obtained.

[0178] Figure 8 This is a diagram 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 including the first element, the second element, and the third element is formed by the processing sequence described in the above embodiment. Figure 8 The horizontal axis of the graph represents the supply amount of the second gas per cycle. Figure 8 The vertical axis of the graph represents the concentration of the second element in the film, and the unit is [atomic % (at. %)].

[0179] Depend on Figure 8 It can be seen that the greater the amount of the second gas supplied per cycle, the greater the amount of the first gas adsorbed on the first adsorption site, and the higher the concentration of the second element in the film. That is, the greater the amount of the second gas supplied in step B, the greater the amount of the second gas adsorbed on the surface of the wafer 200 in step B.

[0180] 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 is increased when the second gas is supplied, or when the concentration of the second gas in the processing chamber 201 is increased, the amount of the second gas adsorbed on the first adsorption site in step B increases. Therefore, in these cases, the amount of the second gas adsorbed on the surface of the wafer 200 in step B increases. In this way, by controlling the amount of the second gas adsorbed on the first adsorption site according to the supply conditions of the second gas in step B, the amount of the second gas adsorbed on the surface of the wafer 200 in step B can be controlled.

[0181] For example, in the above-mentioned method, the case where step B is performed under the condition that the amount of adsorption of the second gas on the surface of the wafer 200 is not saturated is described as an example. However, the present invention is not limited to this method. For example, step B may be performed in a manner that the second gas is adsorbed on all the first adsorption sites that are not adsorbed by the first gas. In this method, the same effect as in the above-mentioned method can be obtained. In this method, the controllability of the amount of adsorption of the second gas can be further improved compared to the case where the method is performed under the condition that saturation is not generated.

[0182] For example, in the above-mentioned method, an example is given in which step A is started before step B. However, the present invention is not limited to this method. For example, step A may be partially performed simultaneously with step B, and step A may be started simultaneously with step B. In this case, the same effect as in the above-mentioned method can be obtained.

[0183] Generally, when hydrophilic ligands are present on the surface of the wafer 200 (hydrophilic adsorption sites are formed), the gas having hydrophilic ligands (hydrophilic gas) becomes less likely to be adsorbed on the surface of the wafer 200. Similarly, when hydrophobic ligands are present on the surface of the wafer 200 (hydrophobic adsorption sites are formed), the gas having hydrophobic ligands (hydrophobic gas) becomes less likely to be adsorbed on the surface of the wafer 200. Here, the hydrophilic ligand refers to a ligand having a charge or high polarity, such as a halide (e.g., fluoride, chloride, bromide, 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), and the like. In addition, hydrophobic ligands refer to alkyl groups (e.g., -CH3, -CH2CH3), hydrogen groups (-H), cycloalkyl groups (e.g., -C3H5, -C4H7, -C5H9, -C6H 11 ), functional groups with a carbocyclic structure (such as phenyl (-C6H5), cyclopentadienyl (Cp)), etc.

[0184] Thus, for example, in step A, when the first gas adsorbed on 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. In addition, in step A, when the first gas adsorbed on 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. In the case of either of these, the first gas becomes easy to hinder the second gas etc. from being adsorbed on the wafer 200, so the second gas becomes less likely to be adsorbed on the first gas etc. adsorbed on the surface of the wafer 200. Therefore, the second gas becomes more likely to be preferentially adsorbed on 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 the second gas adsorbed on the surface of the wafer 200 becomes less likely to exceed the desired amount.

[0185] Here, as the hydrophilic gas, for example, a gas having a hydrophilic ligand among the gases cited as examples of the first gas can be used. In addition, as the hydrophilic gas, even if it is a gas not cited 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 the gases cited as examples of the first gas can be used. As the hydrophobic gas, even if it is a gas not cited as an example of the first gas, a gas having a hydrophobic ligand can be appropriately used.

[0186] For example, in the above-mentioned method, an example is given in which the second element contained in the second gas is an element different from the first element contained in the first gas. However, the present invention is not limited to this method. 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 in the above-mentioned method can be obtained. In addition, in this case, the first layer 300 uniformly containing the first element can also be formed on the surface of the wafer 200.

[0187] The process for each treatment is preferably prepared separately in advance according to the treatment content, and recorded and stored in the storage device 121c via the electric communication line and the external storage device 123. In addition, when starting each treatment, it is preferred that the CPU 121a appropriately selects an appropriate process from the multiple processes recorded and stored in the storage device 121c according to the treatment content. In this way, films of various film types, composition ratios, film qualities, and film thicknesses can be formed with good reproducibility using one substrate processing device. In addition, the burden on the operator can be reduced, and each treatment can be started quickly while avoiding operational errors.

[0188] The above-mentioned process is not limited to the case of newly making, and can also be prepared by, for example, changing an existing process already installed in a substrate processing device. When changing a process, the changed process can also be installed in the substrate processing device via an electrical communication line or a recording medium recording the process. In addition, the input / output device 122 of the existing substrate processing device can be operated to directly change the existing process already installed in the substrate processing device.

[0189] In the above-mentioned method, an example of forming a film using a batch-type substrate processing device that processes a plurality of substrates at a time is described. The present invention is not limited to the above-mentioned method, and for example, it can also be appropriately applied to a case where a film is formed using a single-sheet substrate processing device that processes one or more substrates at a time. In addition, in the above-mentioned method, an example of forming a film using a substrate processing device having a hot-wall type processing furnace is described. The present invention is not limited to the above-mentioned method, and it can also be appropriately applied to a case where a film is formed using a substrate processing device having a cold-wall type processing furnace.

[0190] Also when these substrate processing apparatuses are used, each process can be performed with the same processing steps and processing conditions as those of the above-mentioned embodiment and modified example, and the same effects as those of the above-mentioned embodiment and modified example can be obtained.

[0191] The above-mentioned aspects and modifications can be used in combination as appropriate. The processing steps and processing conditions in this case can be, for example, the same as those of the above-mentioned aspects and modifications.

Claims

1. A substrate processing method, comprising: (a) a step of supplying a first gas to a substrate having a predetermined surface on which a first adsorption site exists, wherein: The first gas is a gas that hinders the second gas from being adsorbed on the first adsorption site; and (b) supplying the second gas to the substrate under the condition that the amount of the second gas adsorbed to the predetermined surface becomes self-limiting, Where (a) starts at the same time as (b) or before (b), The amount of the first gas adsorbed on the predetermined surface is greater than that of the second gas.

2. The substrate processing method according to claim 1, wherein: By controlling the supply conditions of the first gas in (a), the amount of the second gas adsorbed on the predetermined surface in (b) is controlled.

3. The substrate processing method according to claim 2, wherein: (a) The method is performed under the condition that the amount of the first gas adsorbed on the predetermined surface becomes self-limiting and the amount of the first gas adsorbed on the predetermined surface becomes unsaturated.

4. The substrate processing method according to claim 1, wherein: By controlling the supply conditions of the second gas in (b), the amount of the second gas adsorbed on the predetermined surface in (b) is controlled.

5. The substrate processing method according to claim 1, wherein: (b) The step is performed under the condition that the amount of adsorption of the second gas on the predetermined surface does not reach saturation.

6. The substrate processing method according to claim 1, wherein: In (b), the second gas is adsorbed on all of the first adsorption sites that are not adsorbed by the first gas.

7. The substrate processing method according to claim 1, wherein: The first gas has a first element, The second gas has a second element, Through (a) and (b), a first layer including the first element and the second element is formed on the predetermined surface.

8. The substrate processing method according to claim 7, wherein: The method further comprises the step of (c) forming the first adsorption site on at least a portion of the predetermined surface. The method further includes performing a first cycle of (c) after (a) and (b) a predetermined number of times.

9. The substrate processing method according to claim 8, wherein: The method further comprises performing a second cycle of (a) and (c) in sequence for a predetermined number of times, The first cycle and the second cycle are each performed a predetermined number of times.

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

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

12. The substrate processing method according to claim 8, wherein: In (c), a third gas is supplied to the substrate to form the first adsorption site on at least a portion of the predetermined surface.

13. The substrate processing method according to claim 12, wherein: The third gas has a third element, In (c), a second layer including the third element and having the first adsorption site on the surface is formed on at least a portion of the predetermined surface.

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

15. The substrate processing method according to claim 14, wherein: The method further comprises: (e) supplying a fourth gas which is a gas different from the first gas and contains a fourth element, to form a third layer containing the second element and the fourth element on the predetermined surface.

16. The substrate processing method according to claim 1, wherein: In (b), the second gas is supplied from the side of the substrate.

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

18. A method for manufacturing a semiconductor device, comprising: (a) a step of supplying a first gas to a substrate having a predetermined surface on which a first adsorption site exists, wherein: The first gas is a gas that hinders the second gas from being adsorbed on the predetermined surface; and (b) supplying the second gas to the substrate under the condition that the amount of the second gas adsorbed to the predetermined surface becomes self-limiting, Where (a) starts at the same time as (b) or before (b), The amount of the first gas adsorbed on the predetermined surface is greater than that of the second gas.

19. A substrate processing apparatus comprising: A first gas supply system supplies a first gas to a substrate having a predetermined surface on which a first adsorption site exists, wherein: The first gas is a gas that hinders the second gas from being adsorbed on the predetermined surface; a second gas supply system that supplies the second gas to the substrate; and A control unit configured to control the first gas supply system and the second gas supply system so as to be able to perform the following process, wherein: (a) supplying the first gas to the substrate; and (b) supplying the second gas to the substrate under the condition that the amount of the second gas adsorbed to the predetermined surface becomes self-limiting, Where (a) starts at the same time as (b) or before (b), The amount of the first gas adsorbed on the predetermined surface is greater than that of the second gas.

20. A computer-readable recording medium having a program recorded thereon for causing a substrate processing apparatus to execute the following steps through a computer, the steps comprising: (a) a step of supplying a first gas to a substrate having a predetermined surface on which a first adsorption site exists, wherein: The first gas prevents the second gas from being adsorbed on the specified surface; and (b) supplying the second gas to the substrate under the condition that the amount of the second gas adsorbed to the predetermined surface becomes self-limiting, Where (a) starts at the same time as (b) or before (b), The amount of the first gas adsorbed on the predetermined surface is greater than that of the second gas.

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