SUBSTRATE PROCESSING METHOD, SEMICONDUCTOR DEVICE MANUFACTURING APPARATUS, PROGRAM, AND SUBSTRATE PROCESSING APPARATUS

Abstract

A substrate processing method comprising a step for forming a film containing a predetermined element and nitrogen on a substrate by performing, a predetermined number of times, a cycle comprising: (a) a step for forming a first layer by supplying a raw material gas that contains the predetermined element and a halogen element to the substrate; (b) a step for generating an activated species X by plasma-exciting an elemental gas composed of a single element, and supplying the elemental gas including the activated species X to the substrate; and (c) a step for generating an activated species Y by plasma-exciting a reaction gas containing nitrogen, and forming a second layer by supplying the reaction gas including the activated species Y to the substrate. The step (b) further comprises a step for generating an activated species Z by plasma-exciting a compound gas composed of a plurality of elements, and supplying the compound gas including the activated species Z to the substrate, wherein in (b), the ratio of the amount of the compound gas supplied to the amount of the elemental gas supplied is less than 1 / 2.

Description

[Technical Field]

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

[0002] BACKGROUND ART As one step in the manufacturing process of a semiconductor device, a process of forming a film on a substrate by alternately supplying a source gas and a reactive gas to the substrate is sometimes performed (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-135475 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a technique for forming a film on a substrate that has excellent uniformity of film properties within the surface of the substrate. [Means for solving the problem]

[0005] According to one aspect of the present disclosure, (a) forming a first layer by supplying a source gas containing a predetermined element and a halogen element to a substrate; (b) generating activated species X by plasma-exciting an elemental gas composed of one type of element, and supplying the elemental gas containing the activated species X to the substrate; (c) generating activated species Y by plasma-exciting a reactive gas containing nitrogen, and supplying the reactive gas containing the activated species Y to the substrate to form a second layer; a step of forming a film containing the predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further comprises a step of generating activated species Z by plasma-exciting a compound gas composed of a plurality of kinds of elements, and supplying the compound gas containing the activated species Z to the substrate; In (b), a technique is provided in which the ratio of the supply amount of the compound gas to the supply amount of the simple substance gas is set to less than 1 / 2. [Effects of the Invention]

[0006] According to the present disclosure, it is possible to provide a technique for forming a film on a substrate that has excellent uniformity of film properties within the surface of the substrate. [Brief explanation 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 portion in vertical cross section. [Figure 2] FIG. 2 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 portion in a cross section taken along line AA. [Figure 3] FIG. 3 is a schematic configuration diagram of a controller 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. [Figure 4] FIG. 4 is a diagram showing an example of the supply timing of main gases and the supply timing of RF power in a film formation sequence according to one embodiment of the present disclosure. [Figure 5] FIG. 5 is a diagram showing an example of a film formation sequence in the embodiment. [Figure 6] FIG. 6 is a diagram showing the measurement results of the wet etching rates of the films formed in the examples. [Figure 7] FIG. 7 is a graph showing the relationship between the wet etching rate and the chlorine concentration of the films formed in the examples. DETAILED DESCRIPTION OF THE INVENTION

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

[0009] (1) Configuration of the substrate processing equipment 1, the process furnace 202 has a heater 207 as a heating means (heating mechanism). 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 (thermal 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 has 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 manifold 209 is made of a metal material such as stainless steel (SUS) and has a cylindrical shape with open upper and lower ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing member. The reaction tube 203 is installed vertically, similar to 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 the cylindrical hollow portion of the processing vessel. The processing chamber 201 is configured to be able to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed in this processing chamber 201, i.e., in this processing vessel.

[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 gas supply pipes 232a to 232c are also referred to as first to third gas supply pipes (R1 to R3), respectively.

[0012] Gas supply pipe 232a is provided with, in order from the upstream side of the gas flow, an MFC 241a, an on-off valve 243a, and a valve 242a. Gas supply pipe 232d is connected to gas supply pipe 232a downstream of valve 242a. Gas supply pipe 232d is provided with, in order from the upstream side of the gas flow, an MFC 241d and an on-off valve 243d.

[0013] Gas supply pipes 232b and 232c are respectively provided with mass flow controllers (MFCs) 241b and 241c, which are flow rate controllers (flow rate control parts), and valves 243b and 243c, which are on-off valves, in order from the upstream side of the gas flow. Gas supply pipe 232e is connected to gas supply pipe 232b downstream of valve 243b. Gas supply pipes 232f and 232g are respectively connected to gas supply pipe 232c downstream of valve 243c. Gas supply pipes 232e to 232g are respectively provided with MFCs 241e to 241g and valves 243e to 243g in order from the upstream side of the gas flow. Gas supply pipes 232a to 232g are made of a metal material, for example, stainless steel (SUS).

[0014] Downstream of valves 243b and 243c of gas supply pipes 232b and 232c, remote plasma units 300b and 300c are provided as excitation units (plasma excitation units, plasma activation mechanisms) that activate (excite) gas with plasma.

[0015] Each of the remote plasma units 300b and 300c is provided with two electrodes (not shown) for generating plasma. By applying power between these two electrodes, gas can be excited into plasma within the remote plasma units 300b and 300c, i.e., the gas can be plasma-excited. Hereinafter, the plasma-excitation of gas will also be simply referred to as "plasma excitation." By applying power, i.e., high-frequency power (RF power), to the electrodes, the plasma-excited gas within the remote plasma units 300b and 300c can be supplied into the processing chamber 201 via the gas supply pipes 232b and 232c and the nozzles 249b and 249c. A first buffer chamber (buffer structure) accommodating a nozzle 249b and a first plasma generation electrode (described later) inside the reaction tube 203 may be provided along the wall surface of the reaction tube 203, thereby constituting a remote plasma unit in which the gas supplied from the nozzle 249b is excited into plasma by the first buffer chamber and the first plasma generation electrode. Similarly, a second buffer chamber accommodating a nozzle 249c and a second plasma generation electrode (described later) inside the reaction tube 203 may be provided along the wall surface of the reaction tube 203, thereby constituting a remote plasma unit in which the gas supplied from the nozzle 249c is excited into plasma by the second buffer chamber and the second plasma generation electrode. Alternatively, the first buffer chamber, the second buffer chamber, and the first plasma generation electrode and the second plasma generation electrode may be configured as a common buffer chamber and plasma generation electrode, respectively.

[0016] 1 and 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, along the inner wall of the reaction tube 203 from the bottom to the top, so as to rise upward in the arrangement direction of the wafers 200. That is, the nozzles 249a to 249c are provided in regions that horizontally surround the wafer arrangement region on the sides of the wafer arrangement region where the wafers 200 are arranged, so as to extend along the wafer arrangement region.

[0017] The nozzle 249a is disposed farther from the exhaust port 231a (described later) than the nozzles 249b and 249c. That is, the nozzles 249b and 249c are disposed closer to the exhaust port 231a than the nozzle 249a. In addition, the nozzles 249b and 249c are disposed symmetrically with respect to the center of the wafer 200 when the wafer 200 is loaded into the processing chamber 201, that is, a line passing through the center of the reaction tube 203 and the center of the exhaust port 231a, in a plan view. The nozzles 249a and 249b are disposed opposite each other on a straight line across the center of the reaction tube 203.

[0018] Gas supply holes 250a to 250c for supplying gas are provided on the side surfaces of the nozzles 249a to 249c, respectively. The gas supply holes 250a to 250c are each opened to face the center of the reaction tube 203, making it possible to supply gas toward the wafer 200. The gas supply holes 250a and 250b are opened to face each other (face each other) on a straight line across the center of the wafer 200, i.e., the center of the reaction tube 203. A plurality of gas supply holes 250a to 250c are provided from the bottom to the top of the reaction tube 203.

[0019] A gas containing a predetermined element and a halogen element is supplied as a source gas from the gas supply pipe 232a into the processing chamber 201 via the MFC 241a, the valve 243a, the valve 242a, and the nozzle 249a.

[0020] A gas consisting of one type of element is supplied as a simple gas from the gas supply pipe 232b into the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b.

[0021] A gas containing nitrogen (N) as a reactive 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.

[0022] From the gas supply pipe 232f, a gas composed of multiple types of elements is supplied as a compound gas into the processing chamber 201 via the MFC 241f, the valve 243f, the gas supply pipe 232c, and the nozzle 249c. Note that although the elemental gas and the compound gas are respectively supplied from the nozzles 249b and 249c in the above description, each gas may be supplied from the same nozzle. Also, although the elemental gas and the reactive gas are respectively supplied from the nozzles 249b and 249c in the above description, each gas may be supplied from the same nozzle. Furthermore, the elemental gas, the reactive gas, and the compound gas may be supplied from a single nozzle (for example, either the nozzles 249b or 249c).

[0023] Inert gas is supplied from the gas supply pipes 232d, 232e, and 232g into the processing chamber 201 via the MFCs 241d, 241e, and 241g, the valves 243d, 243e, and 243g, the gas supply pipes 232a to 232c, and the nozzles 249a to 249c, respectively. The inert gas acts as a purge gas, a carrier gas, a dilution gas, etc.

[0024] The source gas supply system is mainly composed of the gas supply pipe 232a, MFC 241a, valves 243a and 242a, and a gas reservoir. The reactive gas supply system is mainly composed of the gas supply pipe 232b, MFC 241b, and valve 243b. The single gas supply system is mainly composed of the gas supply pipe 232c, MFC 241c, and valve 243c. The compound gas supply system is mainly composed of the gas supply pipe 232f, MFC 241f, and valve 243f. The inert gas supply system is mainly composed of the gas supply pipes 232d, 232e, and 232g, MFCs 241d, 241e, and 241g, and valves 243d, 243e, and 243g.

[0025] Any or all of the various gas supply systems described above may be configured as an integrated gas supply system 248 in which valves 243a-243g, gas reservoirs, MFCs 241a-241g, etc. are integrated. The integrated gas supply system 248 is connected to each of the gas supply pipes 232a-232g, and is configured so that the supply of various gases into the gas supply pipes 232a-232g, i.e., the opening and closing of the valves 243a-243g and the flow rate adjustment by the MFCs 241a-241g, etc., are controlled by a controller 121, which will be described later. The integrated gas supply system 248 is configured as an integrated or separate integrated unit, and can be attached and detached to and from the gas supply pipes 232a-232f, etc., so that maintenance, replacement, expansion, etc. of the integrated gas supply system 248 can be performed on an integrated unit basis.

[0026] An exhaust port 231a for exhausting the atmosphere inside the processing chamber 201 is provided at the bottom of the sidewall of the reaction tube 203. The exhaust port 231a may be provided along the sidewall of the reaction tube 203 from the bottom to the top, i.e., along the wafer arrangement area. An exhaust pipe 231 is connected to the exhaust port 231a. A vacuum pump 246 serving as a vacuum exhaust device is connected to the exhaust pipe 231 via a pressure sensor 245 serving as a pressure detector (pressure detection unit) that detects the pressure inside the processing chamber 201 and an APC (Auto Pressure Controller) valve 244 serving as a pressure regulator (pressure adjustment unit). The APC valve 244 can evacuate and stop the evacuation inside the processing chamber 201 by opening and closing the valve while the vacuum pump 246 is operating. Furthermore, the pressure inside the processing chamber 201 can be adjusted by adjusting the valve opening based on pressure information detected by the pressure sensor 245 while the vacuum pump 246 is operating. An exhaust system is mainly composed of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. A vacuum pump 246 may be included in the exhaust system.

[0027] A seal cap 219 serving as a furnace port cover capable of airtightly closing the lower end opening of the manifold 209 is provided below the manifold 209. The seal cap 219 is made of a metal material such as SUS and is formed in a disk shape. An O-ring 220b serving as a sealing member that abuts against the lower end of the manifold 209 is provided on the upper surface of the seal cap 219. A rotation mechanism 267 for rotating the boat 217 (described later) is provided below the seal cap 219. A rotation shaft 255 of the rotation mechanism 267 is made of a metal material such as SUS and is connected to the boat 217 through the seal cap 219. The rotation mechanism 267 is configured to rotate the boat 217, thereby rotating the wafers 200. The seal cap 219 is configured to be vertically raised and lowered by a boat elevator 115 serving 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 wafers 200 into and out of the processing chamber 201 by raising and lowering the seal cap 219. are.

[0028] A shutter 219s is provided below the manifold 209 as a furnace port cover that can airtightly close the lower end opening of the manifold 209 when the seal cap 219 is lowered and the boat 217 is removed from the processing chamber 201. The shutter 219s is made of a metal material such as SUS and has a disk shape. An O-ring 220c is provided on the upper surface of the shutter 219s as a sealing member that abuts against 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.

[0029] The boat 217, which serves as a support for supporting substrates, is configured to support a plurality of wafers 200, for example, 25 to 200, in multiple stages, horizontally and aligned vertically with their centers aligned. That is, the boat 217 is configured to arrange the plurality of wafers 200 in a horizontal position and spaced apart vertically. 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, also made of a heat-resistant material such as quartz or SiC, are supported in multiple stages. The boat 217 is configured to be able to support each of the plurality of wafers 200.

[0030] A temperature sensor 263 serving as a temperature detector is installed inside the reaction tube 203. By adjusting the power supply to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 can be adjusted to a desired temperature distribution. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0031] 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 also be connected to the controller 121.

[0032] The storage device 121c is configured with, for example, a flash memory, an HDD (Hard Disk Drive), an SSD (Solid State Drive), etc. The storage device 121c readably stores a control program for controlling the operation of the film forming apparatus, a process recipe describing the procedures and conditions of the processes described below, etc. The process recipe is a combination of procedures in the processes described below that are executed by the controller 121 in the film forming 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. The process recipe is also simply referred to as a recipe. In this specification, the term "program" may refer to a recipe alone, a control program alone, or both. The RAM 121b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 121a.

[0033] 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.

[0034] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to an input of an operation command from the input / output device 122. The CPU 121a is configured to control, in accordance with the contents of the read recipe, the flow rate adjustment operation of 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, and the like.

[0035] The controller 121 can be configured by installing the above-mentioned program stored in the external storage device 123 into a computer. The external storage device 123 includes, for example, a magnetic disk such as an HDD, an optical disk such as a CD, a magneto-optical disk such as an MO, and a semiconductor memory such as a USB memory or an SSD. The storage device 121c and the external storage device 123 are configured as computer-readable recording media. Hereinafter, these will be collectively referred to simply as recording media. When the term recording media is used in this specification, it may include only the storage device 121c alone, only the external storage device 123 alone, or both. Note that the program may be provided to the computer using a communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0036] (2) Substrate processing process An example of a substrate processing sequence, i.e., a film formation sequence, for forming a film containing a predetermined element and nitrogen (N) on a wafer 200 as a substrate using the above-described substrate processing apparatus as one step in the manufacturing process of a semiconductor device will be described. In the following description, the operation of each part constituting the substrate processing apparatus is controlled by a controller 121.

[0037] In the film formation sequence of this embodiment shown in FIG. (a) forming a first layer by supplying a source gas containing a predetermined element and a halogen element to the wafer 200; (b) generating activated species X by plasma-exciting an elemental gas composed of one kind of element, and supplying the elemental gas containing the activated species X to the wafer 200; (c) generating activated species Y by plasma-exciting a reactive gas containing N, and supplying the reactive gas containing the activated species Y to the wafer 200 to form a second layer; a predetermined number of times (n times, n is an integer of 1 or more) to form a film containing a predetermined element and N on the wafer 200, (b) further includes a step of supplying activated species Z generated by plasma-exciting a compound gas composed of a plurality of kinds of elements to the wafer 200; In (b), the ratio of the supply amount of the compound gas to the supply amount of the elemental gas is set to less than 1 / 2.

[0038] 4, (b) shows an example in which the ratio of the supply flow rate of the compound gas to the supply flow rate of the elemental gas is set to less than 1 / 2, thereby making the ratio of the supply amount of the compound gas to the supply amount of the elemental gas less than 1 / 2. Note that the ratio of the supply amount of the compound gas to the supply amount of the elemental gas is preferably set to 1 / 3 or less.

[0039] 4, (b) shows an example in which activated species X and activated species Z generated by plasma-exciting an elemental gas and a compound gas, respectively, are supplied to the wafer 200. (c) shows an example in which activated species Y generated by plasma-exciting a reactive gas is supplied to the wafer 200.

[0040] In this specification, for convenience, such a film formation sequence may be expressed as follows: Similar notations will be used in the following descriptions of other aspects and modifications.

[0041] (Source gas → Plasma excited elemental gas / compound gas → Plasma excited reactive gas) × n

[0042] In the film formation sequence shown in Fig. 4, it is preferable to perform evacuation after each of (a) and (c). In this case, the film formation sequence can be expressed as follows.

[0043] (Source gas → Purge → Plasma excited elemental gas / compound gas → Plasma excited reactive gas → Purge) × n

[0044] In the present disclosure, the film containing a predetermined element and N includes a nitride film (SiN film) containing a predetermined element such as silicon, as well as a nitride film containing carbon (C) and oxygen (O). For example, nitride films include a silicon nitride film (SiN film), a silicon carbonitride film (SiCN film), a silicon oxynitride film (SiON film), a silicon oxycarbonitride film (SiOCN film), etc. Below, an example will be described in which the predetermined element is Si and a SiN film is formed as a film containing Si and N.

[0045] In this specification, the term "wafer" may refer to the wafer itself or a laminate of the wafer and a predetermined layer or film formed on its surface. In this specification, the term "surface of a wafer" may refer to the surface of the wafer itself or the surface of a predetermined layer or the like formed on the wafer. In this specification, the phrase "forming a predetermined layer on a wafer" may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. In this specification, the term "substrate" is also synonymous with the term "wafer".

[0046] (Wafer charge and boat load) 1, when a plurality of wafers 200 are loaded into the boat 217 (wafer charge), 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 reaction tube 203 via the O-ring 220b.

[0047] (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 (depressurized) by the vacuum pump 246 so as to reach 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 (pressure adjustment). Furthermore, the wafers 200 inside the processing chamber 201 are heated by the heater 207 so as to reach a desired processing temperature. At this time, the power supply to the heater 207 is feedback-controlled based on temperature information detected by the temperature sensor 263 so as to achieve a desired temperature distribution inside the processing chamber 201 (temperature adjustment). Furthermore, the rotation mechanism 267 starts to rotate the wafers 200. The operation of the vacuum pump 246 and the heating and rotation of the wafers 200 are all continued at least until the processing of the wafers 200 is completed.

[0048] (Gas Charge) Thereafter, valve 242a is closed, and valve 243a is opened to allow the source gas to flow into gas supply pipe 232a. The flow rate of the source gas is adjusted by MFC 241a, and the source gas is stored in gas supply pipe 232a between valves 243a and 242a (hereinafter also referred to as a gas reservoir). This allows the source gas to be filled into the gas reservoir. Once a predetermined amount of source gas has been filled into the gas reservoir, valve 243a is closed, and the state in which the source gas is filled into the gas reservoir is maintained.

[0049] (film formation process) Then, the following steps A, B, and C are executed in sequence.

[0050] [Step A] In step A, a source gas is supplied to the wafer 200 in the processing chamber 201 .

[0051] Specifically, the valve 242a is opened, and the high-pressure source gas filled in the gas reservoir is supplied into the processing chamber 201 in a burst (pulse-like manner) through the gas supply pipe 232a and the nozzle 249a. Hereinafter, this supply method will be referred to as a flash flow. At this time, the valves 243d, 243e, and 243g are opened, and an inert gas is supplied into the processing chamber 201 through each of the nozzles 249a to 249c. Note that the supply of the inert gas may not be performed for some of the methods described below. This step is preferably performed with the exhaust system substantially fully closed (the APC valve 244 substantially fully closed). With the APC valve 244 closed, the pressure in the processing chamber 201 rapidly increases and reaches a predetermined pressure. The pressurized state in the processing chamber 201 is then maintained for a predetermined time, and the wafer 200 is exposed to the high-pressure source gas atmosphere.

[0052] The processing conditions in this step are as follows: Treatment temperature: 250 to 600°C, preferably 300 to 600°C Processing pressure (before flash flow): 30 to 600 Pa Processing pressure (after flash flow): 500 to 1500 Pa Amount of raw material gas supplied (R1): 120 to 360 cc, preferably 120 to 240 cc Raw material gas exposure time: 1 to 20 seconds, preferably 5 to 10 seconds Inert gas supply flow rate (per R1 to R3): 0 to 10 slm, preferably 0 to 5 slm is exemplified.

[0053] In this specification, when a numerical range such as "250 to 600°C" is expressed, it means that the lower limit and the upper limit are included in the range. Therefore, for example, "250 to 600°C" means "250°C or higher and 600°C or lower." The same applies to other numerical ranges. In this specification, the processing temperature means the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure means the pressure inside the processing chamber 201. A gas supply flow rate of 0 slm means that the gas is not supplied. These also apply to the following explanations.

[0054] By supplying, for example, a chlorosilane-based gas as a source gas to the wafer 200 under the above-described processing conditions, a Cl-containing Si-containing layer is formed as a first layer on the top surface of the wafer 200 serving as a base. The Cl-containing Si-containing layer is formed on the top surface of the wafer 200 by physical adsorption or chemical adsorption of chlorosilane-based gas molecules, physical adsorption or chemical adsorption of molecules of a substance formed by partial decomposition of the chlorosilane-based gas, or deposition of Si due to thermal decomposition of the chlorosilane-based gas. The Cl-containing Si-containing layer may be an adsorption layer (physical adsorption layer or chemical adsorption layer) of chlorosilane-based gas molecules or molecules of a substance formed by partial decomposition of the chlorosilane-based gas, or may be a deposition layer of Cl-containing Si. In this specification, the Cl-containing Si-containing layer is also simply referred to as a Si-containing layer.

[0055] If the processing temperature is less than 250°C, it may be difficult for Si to be adsorbed onto the wafer 200, making it difficult to form the first layer. By setting the processing temperature to 250°C or higher, it becomes possible to form the first layer on the wafer 200. By setting the processing temperature to 300°C or higher, it becomes possible to form the first layer more sufficiently on the wafer 200.

[0056] If the processing temperature exceeds 600°C, the source gas, for example, a chlorosilane-based gas, may thermally decompose, resulting in multiple deposits of Si on the wafer 200, making it difficult to form a first layer with a substantially uniform thickness less than one atomic layer. Setting the processing temperature to 600°C or less allows a first layer with a substantially uniform thickness less than one atomic layer to be formed, thereby improving the in-plane film thickness uniformity of the wafer. Here, a layer with a thickness less than one atomic layer refers to an atomic layer that is formed discontinuously, and a layer with a thickness of one atomic layer refers to an atomic layer that is formed continuously. Furthermore, a substantially uniform layer with a thickness less than one atomic layer means that atoms are adsorbed on the surface of the wafer 200 with a substantially uniform density.

[0057] By supplying a source gas, such as a chlorosilane-based gas, to the wafer 200 under the above-described processing conditions, a first layer containing Cl can be formed on the wafer 200. Furthermore, the Cl concentration in the first layer formed on the outer periphery of the wafer 200 can be made the same as the Cl concentration in the first layer formed in the central portion of the wafer 200. Here, the term "same Cl concentration" is used to mean that the Cl concentrations are completely the same, but also include a predetermined error range. The predetermined error range refers to, for example, a ratio of the Cl concentrations at the outer periphery and the central portion of the wafer 200 (outer periphery) / (central portion) of 0.80 to 1.20.

[0058] After the first layer is formed, the valve 242a is closed to stop the supply of source gas into the processing chamber 201. Then, the APC valve 244 is, for example, fully opened to evacuate the processing chamber 201 and remove (purge) any gas remaining in the processing chamber 201. At this time, the valves 243d, 243e, and 243g are left open to maintain the supply of inert gas into the processing chamber 201. The inert gas supplied through each of the nozzles 249a to 249c acts as a purge gas, thereby purging the processing chamber 201.

[0059] The processing conditions for purging are as follows: Treatment temperature: 250 to 600°C, preferably 300 to 600°C Treatment pressure: 1 to 70 Pa, preferably 1 to 30 Pa Inert gas supply flow rate (per R1 to R3): 0.05 to 20 slm, preferably 1 to 5 slm Inert gas supply time: 1 to 20 seconds, preferably 1 to 10 seconds is exemplified.

[0060] The source gas may be, for example, a silane-based gas containing silicon (Si) as the main element constituting the film formed on the wafer 200. The silane-based gas may be, for example, a gas containing halogen and Si, i.e., a halosilane-based gas. Halogen includes chlorine (Cl), fluorine (F), bromine (Br), iodine (I), and the like. The halosilane-based gas may be, for example, the above-mentioned chlorosilane-based gas containing Cl and Si.

[0061] The source gas may be, for example, a chlorosilane-based gas such as dichlorosilane (SiH2Cl2, abbreviated as DCS) gas, monochlorosilane (SiH3Cl, abbreviated as MCS) gas, trichlorosilane (SiHCl3, abbreviated as TCS) gas, tetrachlorosilane (SiCl4, abbreviated as 4CS) gas, hexachlorodisilane gas (Si2Cl6, abbreviated as HCDS) gas, or octachlorotrisilane (Si3Cl8, abbreviated as OCTS) gas. One or more of these may be used as the source gas.

[0062] The inert gas may be, for example, nitrogen (N2) gas or a rare gas such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, or xenon (Xe) gas. One or more of these may be used as the inert gas. This also applies to each step described below.

[0063] [Step B] After step A is completed, the elemental gas and compound gas are each plasma-excited and supplied to the wafer 200 in the processing chamber 201, that is, to the first layer (Si-containing layer) formed on the wafer 200.

[0064] Specifically, with the APC valve 244 open, i.e., with the processing chamber 201 evacuated, valves 243b and 243f are opened to allow elemental gases and compound gases to flow into the gas supply pipes 232b and 232c, respectively. The elemental gases and compound gases are adjusted in flow rate by MFCs 241b and 241f, respectively, supplied into the processing chamber 201 via nozzles 249b and 249c, and exhausted from the exhaust port 231a. At this time, the elemental gases and compound gases are supplied to the wafer 200 from the side of the wafer 200 (i.e., from the outer edge of the wafer 200 in a direction in-plane) (elemental gas and compound gas supply). At this time, valves 243d, 243e, and 243g are kept open to maintain the supply of inert gas into the processing chamber 201.

[0065] At this time, by applying RF power to the electrodes for plasma generation, the elemental gas and compound gas supplied into the gas supply pipes 232b and 232c are plasma-excited in the remote plasma units 300b and 300c, respectively, and activated species X is generated from the elemental gas and activated species Z is generated from the compound gas. The elemental gas and compound gas containing the activated species X and activated species Z generated in this way are supplied to the wafer 200 (plasma-excited elemental gas / compound gas supply).

[0066] When hydrogen (H2) gas is used as a single element gas, the H2 gas is excited into plasma and becomes H2 * and other activated species X are generated and supplied to the wafer 200. Note that * denotes a radical. The same applies to the following explanation.

[0067] By using a compound gas composed of multiple elements, for example, a hydrogen nitride gas containing nitrogen (N) and hydrogen (H), the hydrogen nitride gas is plasma-excited to produce NH3 *and the like are generated and supplied to the wafer 200.

[0068] The processing conditions in this step are as follows: Treatment temperature: 250 to 600°C, preferably 300 to 600°C Treatment pressure: 1 to 100 Pa, preferably 1 to 50 Pa Single gas supply flow rate: 0.1 to 3.0 slm, preferably 0.2 to 1.0 slm Single gas supply time: 5 to 60 seconds, preferably 5 to 20 seconds Compound gas supply flow rate: 0.05 to 1.0 slm, preferably 0.1 to 0.5 slm Compound gas supply time: 5 to 60 seconds, preferably 5 to 20 seconds Inert gas supply flow rate (per R1 to R3): 0 to 10 slm, preferably 0 to 1.5 slm High frequency power (RF power): 50 to 1000 W, preferably 50 to 300 W is exemplified.

[0069] By supplying plasma-excited elemental gases and compound gases to the wafer 200 under the above conditions, the first layer (Si-containing layer) formed on the surface of the wafer 200 in step A is modified so that Cl, a halogen element, is desorbed from the first layer. Also, a portion of the first layer is modified, for example, to become nitrided. In this way, a layer obtained by modifying the first layer (hereinafter referred to as a modified layer) is formed on the surface of the wafer 200. This will be explained in detail below.

[0070] By plasma-exciting the elemental gas under the above-mentioned conditions and supplying the elemental gas containing the activated species X to the wafer 200, Cl can be desorbed from the first layer formed on the wafer 200.

[0071] However, when the elemental gas is supplied from the side of the wafer 200, the activated species X supplied into the processing chamber 201 flows from the outer periphery of the wafer 200 toward the center. *) tends to be consumed (discharged) by bonding with Cl on the first layer formed on the outer periphery of the wafer 200, and is less likely to reach the center. Therefore, the degree of desorption of Cl in the center of the wafer 200 is weaker than the degree of desorption of Cl in the outer periphery of the wafer 200, and the Cl concentration in the center of the wafer 200 may be higher than the Cl concentration in the outer periphery.

[0072] Therefore, in this step, the plasma-excited compound gas is supplied from the side of the wafer 200 so that its supply amount (supply flow rate in this embodiment) is less than half of the supply amount (supply flow rate in this embodiment) of the plasma-excited elemental gas. Under these conditions, the activated species Z supplied into the processing chamber 201 flows from the outer periphery of the wafer 200 toward the center. Since the supply amount of the compound gas in this step is smaller than the supply amount of the elemental gas, the activated species Z (e.g., NH3 * ) is consumed by bonding with Si on the first layer formed on the outer periphery of the wafer 200, for example, and hardly reaches the central portion. This makes it possible to make the degree of inhibition of Cl desorption at the outer periphery of the wafer 200 stronger than the degree of inhibition of Cl desorption at the central portion. Therefore, the degree of Cl desorption at the outer periphery of the wafer 200 by the activated species X can be made to be approximately the same as the degree of Cl desorption at the central portion, making it possible to make the Cl concentration at the outer periphery and the Cl concentration at the central portion the same. Here, the term "same Cl concentration" is used to mean that the Cl concentrations are completely the same, as well as within a predetermined error range. The predetermined error range refers, for example, to a ratio of the Cl concentrations at the outer periphery and the central portion of the wafer 200 (outer periphery) / (central portion) being 0.80 or more and 1.20 or less.

[0073] The reason why supplying the active species Z to the wafer 200 can inhibit the desorption of Cl from the first layer is thought to be that the active species Z having a three-dimensional structure is adsorbed on the surface of the wafer 200, and the active species Z having polarity is adsorbed, thereby inhibiting the active species X from reaching the first layer.

[0074] When the ratio of the supply amount of the plasma-excited compound gas to the supply amount of the plasma-excited elemental gas is ½ or more, an amount of the supplied activated species Z greater than the amount that inhibits desorption of Cl may reach the central portion of the wafer 200, inhibiting desorption of Cl from almost the entire surface of the first layer. That is, when the ratio of the supply amount of the plasma-excited compound gas to the supply amount of the plasma-excited elemental gas is ½ or more, the Cl desorption effect obtained by supplying the activated species X may be suppressed over the entire surface of the wafer 200, and the Cl desorption effect by the activated species X may not be sufficiently obtained. By setting the ratio of the supply amount of the plasma-excited compound gas to the supply amount of the plasma-excited elemental gas to less than ½, the arrival of the activated species Z at the central portion of the wafer 200 is restricted, and the Cl desorption suppression effect by the activated species Z at the peripheral portion can be obtained while maintaining the Cl desorption effect by the activated species X at the central portion.

[0075] If the treatment temperature is less than 250°C, the Cl elimination reaction caused by the active species X may not occur easily. By setting the treatment temperature to 250°C or higher, it is possible to promote the Cl elimination reaction caused by the active species X. By setting the treatment temperature to 300°C or higher, it is possible to more reliably proceed the Cl elimination reaction caused by the active species X.

[0076] If the treatment temperature exceeds 600°C, the reaction of inhibiting desorption of Cl by the active species Z may not occur easily. By setting the treatment temperature to 600°C or less, it is possible to promote the reaction of inhibiting desorption of Cl by the active species Z.

[0077] After forming the modified layer on the wafer 200, the valves 243b and 243f are closed, the application of RF power to the plasma generating electrode is stopped, and the supply of elemental gases and compound gases into the processing chamber 201 is stopped. At this time, the valves 243d, 243e, and 243g are left open to maintain the supply of the inert gas into the processing chamber 201.

[0078] As the single gas, in addition to the above-mentioned H2 gas, for example, nitrogen (N2) gas, or a rare gas such as argon (Ar) gas or helium (He) gas, or at least any of these can be used.

[0079] When N2 gas is used as the single gas, the N2 gas is excited into plasma and * , N2 * When Ar gas is used as the single gas, the Ar gas is plasma-excited to produce activated species X such as Ar * When He gas is used as the single gas, the He gas is plasma-excited to produce activated species X such as He * and other activated species X are generated.

[0080] As the compound gas, for example, a hydrogen nitride gas such as ammonia (NH3) gas, diazene (N2H2) gas, hydrazine (N2H4) gas, N3H8 gas, etc. As the compound gas, one or more of these can be used.

[0081] When a hydrogen nitride gas is used as the compound gas, the hydrogen nitride gas is plasma-excited to form NH * , NH2 * , NH3 * Active species Z such as

[0082] [Step C] After step B is completed, a reactive gas is plasma-excited and supplied to the wafer 200 in the processing chamber 201, i.e., to the modified layer formed on the wafer 200. In this embodiment, the processing chamber 201 is not purged between steps B and C.

[0083] Specifically, with the APC valve 244 open, i.e., with the processing chamber 201 evacuated, the valve 243c is opened to allow the reactive gas to flow into the gas supply pipe 232c. The reactive gases are adjusted in flow rate by the MFC 241c, supplied into the processing chamber 201 via the nozzle 249c, and exhausted from the exhaust port 231a. At this time, the reactive gas is supplied to the wafer 200 from the side of the wafer 200 (reactive gas supply). At this time, the valves 243d, 243e, and 243g are kept open to maintain the supply of the inert gas into the processing chamber 201.

[0084] At this time, by applying RF power to the electrode for plasma generation, the reactive gas supplied into the gas supply pipe 232c is excited into plasma in the remote plasma unit 300c, generating activated species Y. The reactive gas containing the activated species Y thus generated is supplied to the wafer 200 (plasma-excited reactive gas supply).

[0085] When a hydrogen nitride gas containing N and H is used as the reactive gas containing N, the hydrogen nitride gas is plasma-excited to produce NH * , NH2 * , NH3 * and the like are generated and supplied to the wafer 200.

[0086] The processing conditions in this step are as follows: Treatment temperature: 250 to 600°C, preferably 300 to 600°C Treatment pressure: 1 to 100 Pa, preferably 1 to 50 Pa Reactant gas supply rate: 0.1 to 10 slm, preferably 0.5 to 5.0 slm Reaction gas supply time: 1 to 60 seconds, preferably 10 to 40 seconds Inert gas supply flow rate (per R1 to R3): 0 to 10 slm, preferably 0 to 1.5 slm High frequency power (RF power): 50 to 1000 W, preferably 50 to 300 W is exemplified.

[0087] By supplying the reactive gas to the wafer 200 under the above-described processing conditions, at least a portion of the modified layer formed on the surface of the wafer 200 in step B is nitrided (modified). As a result, a silicon nitride layer (SiN layer) containing Si and N is formed as a second layer on the surface of the wafer 200. When the second layer is formed, impurities such as Cl contained in the modified layer form gaseous substances containing at least Cl during the process of the modification reaction by the plasma-excited reactive gas, and are exhausted from the processing chamber 201. As a result, the second layer contains fewer impurities such as Cl than the modified layer formed in step B.

[0088] If the treatment temperature is less than 250°C, the reaction gas is difficult to thermally decompose, which may make it difficult to form the second layer. By setting the treatment temperature to 250°C or higher, it becomes possible to form the second layer. By setting the treatment temperature to 300°C or higher, it becomes possible to reliably form the second layer.

[0089] If the treatment temperature exceeds 600°C, the thermal decomposition of the reactive gas may become excessive, making it difficult to form the second layer. By setting the treatment temperature to 600°C or less, excessive thermal decomposition of the reactive gas can be suppressed, making it possible to form the second layer.

[0090] After the second layer is formed on the wafer 200, the valve 243c is closed, the application of RF power to the plasma generating electrode is stopped, and the supply of the reactive gas into the processing chamber 201 is stopped. Then, gases remaining in the processing chamber 201 are removed from the processing chamber 201 using the same processing procedures and conditions as those for purging in step A.

[0091] The reactive gas may be, for example, a hydrogen nitride gas such as NH3 gas, N2H2 gas, N2H4 gas, N3H8 gas, etc. One or more of these may be used as the reactive gas.

[0092] In addition to these, a gas containing N, C, and H can also be used as the reactive gas. The N, C, and H-containing gas can be, for example, an amine-based gas or an organic hydrazine-based gas. The N, C, and H-containing gas can be an N-containing gas, a C-containing gas, an H-containing gas, or an N- and C-containing gas.

[0093] Examples of the reactive gas include ethylamine-based gases such as monoethylamine (C2H5NH2, abbreviated as MEA) gas, diethylamine ((C2H5)2NH, abbreviated as DEA) gas, and triethylamine ((C2H5)3N, abbreviated as TEA) gas; methylamine-based gases such as monomethylamine (CH3NH2, abbreviated as MMA) gas, dimethylamine ((CH3)2NH, abbreviated as DMA) gas, and trimethylamine ((CH3)3N, abbreviated as TMA) gas; and organic hydrazine-based gases such as monomethylhydrazine ((CH3)HN2H2, abbreviated as MMH) gas, dimethylhydrazine ((CH3)2N2H2, abbreviated as DMH) gas, and trimethylhydrazine ((CH3)2N2(CH3)H, abbreviated as TMH) gas. One or more of these can be used as the reactive gas. The reactive gas may be the same as the compound gas, or may be a different gas. When the same gas is used, the activated species Z and the activated species Y may be the same activated species.

[0094] [Perform the cycle a specified number of times] By performing the above-described steps A, B, and C asynchronously, i.e., by repeating the cycle a predetermined number of times (n times, where n is an integer equal to or greater than 1), a SiN film can be formed on the surface of wafer 200. The above-described cycle is preferably repeated multiple times. That is, it is preferable to make the thickness of the SiN layer formed per cycle thinner than the desired film thickness, and to repeat the above-described cycle multiple times until the film formed by stacking SiN layers reaches the desired film thickness.

[0095] In the above-mentioned step B, by desorbing Cl from the first layer, it is possible to reduce the wet etching rate (WER) of the SiN film formed by repeating the above-mentioned cycle.

[0096] In the above-described step B, by making the Cl concentration at the outer periphery of the wafer 200 (substantially) the same as the Cl concentration at the center of the wafer 200, the WER at the center and outer periphery of the SiN film formed by repeating the above-described cycle can be made substantially the same. This makes it possible to improve the uniformity of the wet etching process of the SiN film within the wafer surface (hereinafter simply referred to as in-plane uniformity). In other words, the film characteristics at the center and outer periphery of the SiN film can be made substantially the same, thereby improving the in-plane uniformity of the film characteristics of the SiN film.

[0097] (After purging and atmospheric pressure recovery) After the process of forming a nitride film of a desired thickness on the wafer 200 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 (atmospheric pressure return).

[0098] (Boat unloading and wafer discharge) Thereafter, the seal cap 219 is lowered by the boat elevator 115 to open the lower end of the reaction tube 203. Then, the processed wafers 200, supported by the boat 217, are unloaded from the lower end of the reaction tube 203 to the outside of the reaction tube 203 (boat unloading). Thereafter, the processed wafers 200 are removed from the boat 217 (wafer discharging).

[0099] (3) Effects of this mode According to this aspect, one or more of the following effects can be obtained.

[0100] (a) In step B, supplying an elemental gas causes the activated species X to desorb Cl from the first layer. This makes it possible to densify the first layer and to make the film finally formed on the wafer 200 a film with a low WER. Furthermore, supplying a compound gas in step B causes the activated species Z to inhibit desorption of Cl from the first layer, thereby controlling the distribution of the degree of desorption of Cl by the activated species X within the surface of the wafer 200.

[0101] Furthermore, by setting the ratio of the supply amount of the compound gas to the supply amount of the elemental gas to less than 1 / 2 in step B, under the condition that the degree of Cl desorption at the outer periphery of the wafer 200 is stronger than the degree of Cl desorption at the central portion of the wafer 200, the degree of inhibition (of Cl desorption) at the outer periphery of the wafer 200 can be made stronger than the degree of inhibition (of Cl desorption) at the central portion of the wafer 200. As a result, after step B is performed, the Cl concentration in the first layer at the outer periphery of the wafer 200 can be made the same as the Cl concentration in the first layer at the central portion of the wafer 200. As a result, the WER at the central portion and the outer periphery of the film finally formed on the wafer 200 can be made substantially the same, and the film can be made to have excellent in-plane WER uniformity. As a result, it is possible to form a film with low WER and excellent in-plane uniformity of WER, i.e., it is possible to form a film with excellent film properties and excellent in-plane uniformity of film properties.

[0102] (b) Furthermore, in step B, by setting the ratio of the compound gas supply rate to the elemental gas supply rate to 1 / 3 or less, it is possible to reliably form a film with low WER and excellent in-plane WER uniformity. If the ratio of the compound gas supply rate to the elemental gas supply rate exceeds 1 / 3, the Cl concentration, particularly at the center of the wafer 200, cannot be sufficiently reduced, and the desired in-plane WER uniformity may not be obtained.

[0103] (c) In step B, by setting the ratio of the compound gas supply rate to the elemental gas supply rate to less than 1 / 2, it is possible to form a film with low WER and excellent in-plane WER uniformity even when the processing temperature in steps A to C is set to a relatively low temperature of 250 to 600° C. By setting the processing temperature in steps A to C to a relatively low temperature, damage to the processing furnace 202 and the wafers 200 can be reduced.

[0104] (d) In step B, by setting the ratio of the supply amount of the compound gas to the supply amount of the elemental gas to be less than 1 / 2, it is possible to form a film with low WER and excellent in-plane WER uniformity even when processing is performed using a so-called vertical processing furnace in which both the elemental gas and the compound gas are supplied from the side of the wafer 200. Since a batch-type vertical processing furnace that processes multiple wafers 200 at once can be used, the productivity of the film formation process can be improved.

[0105] <Other Aspects of the Present Disclosure> Although the embodiments of the present disclosure have been specifically described above, the present disclosure is not limited to the above-described embodiments and can be modified in various ways without departing from the spirit of the present disclosure.

[0106] Although the above-described embodiment has been described as an example in which a silicon nitride film is used, the present disclosure is not limited thereto. For example, the present disclosure can also be suitably applied to the formation of a nitride film (metal nitride film) containing a metal element such as titanium (Ti), zirconium (Zr), hafnium (Hf), tantalum (Ta), niobium (Nb), molybdenum (Mo), tungsten (W), yttrium (Y), strontium (Sr), lanthanum (La), ruthenium (Ru), or aluminum (Al) as a main element.

[0107] For example, the present disclosure can also be suitably applied to the case where a metal nitride film such as a titanium nitride film (TiN film), a hafnium nitride film (HfN film), a tantalum nitride film (TaN film), or an aluminum nitride film (AlN film) is formed on a wafer 200 using titanium tetrachloride (TiCl4) gas, hafnium tetrachloride (HfCl4) gas, tantalum pentachloride (TaCl5) gas, trimethylaluminum (Al(CH3)3, abbreviated as TMA) gas, or the like, by the film formation sequence shown below.

[0108] (TiCl4 → H2 * →NH3 * )×n ⇒ TiN (HfCl4 → H2 * →NH3 * )×n ⇒ HfN (TaCl5 → H2 * →NH3 * )×n ⇒ TaN (TMA → H2 * →NH3 * )×n ⇒ AlN

[0109] The process procedure and process conditions of the film formation process in this case can be the same as those of the above-mentioned embodiment and modified example. In these cases, the same effects as those of the above-mentioned embodiment and modified example can be obtained. In other words, the present disclosure can be suitably applied to the formation of a metalloid nitride film containing a metalloid element such as Si as a main element, or the formation of a metal nitride film containing the above-mentioned various metal elements as a main element.

[0110] In the above-described embodiment, the adjustment of the supply rate of the compound gas relative to the supply rate of the elemental gas in step B is performed by adjusting the supply flow rate of the compound gas relative to the supply flow rate of the elemental gas. However, the present disclosure is not limited to this. For example, the adjustment may be performed by adjusting at least one of the following in the process chamber 201: the partial pressure of the compound gas relative to the partial pressure of the elemental gas, the concentration of the compound gas relative to the concentration of the elemental gas, and the supply time of the compound gas relative to the supply time of the elemental gas. Specifically, the ratio of the supply rate of the compound gas relative to the supply rate of the elemental gas may be set to less than 1 / 2 by setting the ratio of the partial pressure of the compound gas relative to the partial pressure of the elemental gas, the ratio of the supply flow rate of the compound gas relative to the supply flow rate of the elemental gas, the ratio of the concentration of the compound gas relative to the concentration of the elemental gas, or the ratio of the supply time of the compound gas relative to the supply time of the elemental gas, or two or more of these to less than 1 / 2. In these cases, the same effects as those in the above-described embodiment can be obtained.

[0111] In the above-described embodiment, an example in which the supply of the elemental gas and the supply of the compound gas to the wafer 200 in step B are started and stopped simultaneously has been described, but the present disclosure is not limited to this. For example, the supply of the compound gas may be started before the supply of the elemental gas is started, and then the elemental gas and the compound gas are supplied simultaneously. Also, in a state in which the elemental gas and the compound gas are supplied simultaneously, the supply of the compound gas may be stopped before the supply of the elemental gas is stopped, and then the supply of the elemental gas is stopped. In these cases, the same effects as those in the above-described embodiment can be obtained.

[0112] In the above embodiment, an example has been described in which the elemental gas is plasma-excited in the remote plasma unit 300b and the compound gas is plasma-excited in the remote plasma unit 300c, and the activated species X and activated species Z are supplied into the processing chamber 201 via the nozzles 249b and 249c, respectively. However, the present disclosure is not limited to this. For example, the elemental gas and the compound gas may be mixed in a supply pipe, and then the mixed gases may be plasma-excited in one remote plasma unit to generate the activated species X and activated species Z. In this case, a mixed gas of the elemental gas and the compound gas containing the activated species X and activated species Z is supplied to the wafer 200.

[0113] In the above embodiment, the supply of the source gas in step A is performed by flash flow, but the present disclosure is not limited to this. For example, the source gas may be supplied in the same manner as the gas supply method in steps B and C. In this case, the same effects as those in the above embodiment can be obtained.

[0114] It is preferable that the recipes used for each process are individually prepared according to the process content and stored in the storage device 121c via an electric communication line or an external storage device 123. Then, when starting each process, it is preferable that the CPU 121a appropriately selects an appropriate recipe according to the process content from among the multiple recipes stored in the storage device 121c. This makes it possible to reproducibly form films with various film types, composition ratios, film qualities, and film thicknesses using a single substrate processing device. It also reduces the burden on the operator, prevents operational errors, and enables each process to be started quickly.

[0115] The above-mentioned recipes do not necessarily have to be newly created, but may be prepared by modifying an existing recipe already installed in the substrate processing apparatus. When modifying a recipe, the modified recipe may be installed in the substrate processing apparatus via an electric communication line or a recording medium on which the modified recipe is recorded. Alternatively, an existing recipe already installed in the substrate processing apparatus may be directly modified by operating the input / output device 122 provided in the existing substrate processing apparatus.

[0116] In the above-described embodiment, an example of forming a film using a substrate processing apparatus having a hot-wall type processing furnace has been described. However, the present disclosure is not limited to the above-described embodiment, and can also be suitably applied to a case where a film is formed using a substrate processing apparatus having a cold-wall type processing furnace.

[0117] When such a substrate processing apparatus is used, each process can be performed under the same process procedures and conditions as in the above-described embodiment, and the same effects as in the above-described embodiment can be obtained.

[0118] The above-described embodiments can be used in combination as appropriate. In this case, the processing procedures and processing conditions can be the same as those of the above-described embodiments, for example. [Example]

[0119] (Example) Using the above-mentioned substrate processing apparatus, the following film formation sequence was carried out to form SiN films on wafers, thereby producing Samples 1 to 6 (see FIG. 5).

[0120] Sample 1: (source gas → purge → plasma-excited reactive gas → purge) × n Sample 2: (source gas → purge → plasma-excited reactive gas → purge) × n Sample 3: (source gas → purge → plasma excited compound gas → plasma excited reactant gas → purge) × n Sample 4: (Source gas → Purge → Plasma excited simple substance gas → Plasma excited reactive gas → Purge) × n Sample 5: (Source gas → Purge → Plasma excited elemental gas / compound gas → Plasma excited reactive gas → Purge) × n Sample 6: (Source gas → Purge → Plasma excited elemental gas / compound gas → Plasma excited reactive gas → Purge) × n

[0121] FIG. 5 shows that the element gas, the reactive gas, and the compound gas are excited to supply activated species X, activated species Y, and activated species Z, respectively.

[0122] DCS gas was used as the source gas, H gas as the elemental gas, NH gas as the compound gas and reactive gas, and N gas as the inert gas, except for sample 6, where N gas was used as the elemental gas.

[0123] The processing conditions were set to predetermined conditions within the range of processing conditions for each step shown in the above-mentioned embodiment, except that in Sample 2, the purging time performed after supplying the source gas was set to a long time of 30 seconds.

[0124] After preparing Samples 1 to 6, the WER was measured at a plurality of predetermined locations on the SiN film formed on the wafer for each of Samples 1 to 6. The measurement results are shown in FIG.

[0125] The vertical axis of Figure 6 shows the WER (Å / min) of the SiN film in 1% hydrofluoric acid (1% HF aqueous solution). The horizontal axis of Figure 6 shows a predetermined position of the SiN film on the diameter of a 300 mm diameter wafer. For example, -150 (mm) indicates one end of the wafer diameter, 0 (mm) indicates the midpoint of the wafer diameter (the center point of the wafer), and 150 (mm) indicates the other end of the wafer diameter. In Figure 6, ●, ■, ×, △, ◇, and ■ indicate the measurement results for Samples 1 to 6, respectively.

[0126] As shown in Figure 6, it was confirmed that Sample 1 had the highest WER. It was also confirmed that Sample 2 had the second highest WER, and Sample 3 had the third highest WER. These results show that the WER cannot be significantly reduced even if the purging time after the supply of the source gas is extended or if a compound gas is supplied after the supply of the source gas.

[0127] In contrast, it was confirmed that Sample 4 had a significantly reduced WER. This indicates that supplying a single gas after supplying the source gas can reduce the WER. On the other hand, it was confirmed that Sample 4 had a significantly different WER within the wafer surface compared to Samples 1 to 3. Specifically, it was confirmed that the difference in WER between the periphery and center of the wafer was within 2 Å / min for all Samples 1 to 3, whereas it was approximately 5 Å / min for Sample 4. This indicates that supplying (only) a single gas after supplying the source gas can reduce the WER, but it also deteriorates the uniformity (in-plane uniformity) of the wet etching process within the wafer surface.

[0128] It was confirmed that Sample 5 could reduce the WER and maintain good in-plane uniformity compared to Samples 1 to 3. Specifically, it was confirmed that Sample 5 could maintain the difference in WER between the peripheral and central portions of the wafer within 2 Å / min. From the above, it was found that supplying both elemental gases and compound gases after supplying the source gas could reduce the WER and maintain good in-plane uniformity. It is preferable that the ratio of WER between the peripheral and central portions of the wafer (periphery) / (central portion) be 0.80 or more and 1.20 or less.

[0129] It was also confirmed that Sample 6 also provided results similar to those of Sample 5. This shows that results similar to those of Sample 5 can be obtained when N2 gas is used as the single gas.

[0130] After preparing Samples 1 to 6, the WER and Cl concentration at predetermined locations on the SiN film formed on the wafer were measured for Samples 4 and 5. The measurement results are shown in FIG.

[0131] The vertical axis of Fig. 7 shows the Cl concentration in the SiN film (atoms / cm 3 ) in Fig. 7. The horizontal axis of Fig. 7 shows the WER (Å / min) of the SiN film in 1% hydrofluoric acid (1% HF aqueous solution). The circles, double circles, triangles, and half-edges in Fig. 7 respectively represent the WER and Cl concentration at the periphery of the wafer for Sample 4, the WER and Cl concentration at the center of the wafer for Sample 4, the WER and Cl concentration at the periphery of the wafer for Sample 5, and the WER and Cl concentration at the center of the wafer for Sample 5.

[0132] 7, it was confirmed that the difference in Cl concentration between the peripheral and central parts of the wafer was relatively large in Sample 4. In contrast, it was confirmed that the difference in Cl concentration between the peripheral and central parts of the wafer was relatively small in Sample 5.

[0133] Furthermore, it was confirmed that Sample 4 had a relatively large difference in WER between the periphery and center of the wafer, meaning that the in-plane uniformity was poor. In contrast, Sample 5 had a relatively small difference in WER between the periphery and center of the wafer, meaning that the in-plane uniformity was good.

[0134] These results confirmed that there is a correlation between the difference in Cl concentration between the periphery and center of the wafer and the quality of the in-plane WER uniformity, and that the smaller the difference in Cl concentration between the periphery and center of the wafer, the better the in-plane WER uniformity. [Explanation of symbols]

[0135] 200 wafers 201 Processing Room

Claims

1. (a) forming a first layer by supplying a source gas containing a predetermined element and a halogen element to a substrate; (b) generating activated species X by plasma-exciting H gas, and supplying the H gas containing the activated species X to the substrate; (c) generating activated species Y by plasma-exciting a reactive gas containing nitrogen, and supplying the reactive gas containing the activated species Y to the substrate to form a second layer; a step of forming a film containing the predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further includes a step of generating activated species Z by plasma-exciting a compound gas composed of a plurality of types of elements, and supplying the compound gas containing the activated species Z to the substrate; In (b), the ratio of the supply amount of the compound gas to the supply amount of H 2 gas is less than 1 / 2.

2. In (b), the ratio of the partial pressure of the compound gas to the partial pressure of H 2 gas is less than 1 / 2; The substrate processing method according to claim 1 .

3. In (b), the ratio of the concentration of the compound gas to the concentration of H 2 gas is less than 1 / 2; 3. The substrate processing method according to claim 1.

4. In (b), the ratio of the supply flow rate of the compound gas to the supply flow rate of H 2 gas is less than 1 / 2; 3. The substrate processing method according to claim 1.

5. In (b), the ratio of the supply time of the compound gas to the supply time of the H 2 gas is less than 1 / 2.

3. The substrate processing method according to claim 1.

6. In (b), the desorption of the halogen element from the first layer by the active species X is inhibited by the active species Z, and the degree of inhibition at the outer periphery of the substrate is made stronger than the degree of inhibition at the center of the substrate.

3. The substrate processing method according to claim 1.

7. In (a), the halogen element concentration in the first layer formed in the outer peripheral portion before (b) is made the same as the halogen element concentration in the first layer formed in the central portion. The substrate processing method according to claim 6 .

8. In (b), the halogen element concentration in the first layer formed in the outer periphery after (b) is made lower than the halogen element concentration in the first layer formed in the outer periphery before (b) is made the same as the halogen element concentration in the first layer formed in the central portion after (b). The substrate processing method according to claim 7 .

9. (c) after which wet etching is performed using a hydrogen fluoride aqueous solution having a hydrogen fluoride concentration of 1 mass %, the ratio of the wet etching rate in the outer periphery to the wet etching rate in the central portion is 0.80 or more and 1.20 or less. The substrate processing method according to claim 8 .

10. (a) to (c) are carried out at a temperature of 250 to 600°C; 3. The substrate processing method according to claim 1.

11. 3. The substrate processing method according to claim 1, wherein in (b), a ratio of the supply amount of the compound gas to the supply amount of H.sub.2 gas is set to 1 / 3 or less.

12. In (b), both H2 gas and the compound gas are supplied from the side of the substrate.

3. The substrate processing method according to claim 1.

13. The source gas is a chlorosilane-based gas.

3. The substrate processing method according to claim 1.

14. the compound gas is a hydrogen nitride gas, The hydrogen nitride gas is at least one of ammonia gas and hydrazine gas.

3. The substrate processing method according to claim 1.

15. (a) supplying a source gas containing a predetermined element and a halogen element to a substrate to form a first layer; (b) supplying activated species X generated by plasma-exciting H2 gas to the substrate; (c) supplying activated species Y generated by plasma-exciting a nitrogen-containing reactive gas to the substrate to form a second layer; a step of forming a film containing a predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further includes a step of supplying activated species Z generated by plasma-exciting a compound gas composed of a plurality of kinds of elements to the substrate; In the method (b), the desorption of the halogen element from the first layer caused by the activated species X is inhibited by the activated species Z.

16. In (b), the degree of inhibition of desorption of the halogen element in the outer periphery of the substrate is made stronger than the degree of inhibition in the central portion of the substrate. The substrate processing method according to claim 15.

17. (a) supplying a source gas containing a predetermined element and a halogen element to a substrate to form a first layer; (b) supplying activated species X generated by plasma-exciting H2 gas to the substrate from the side of the substrate; (c) supplying activated species Y generated by plasma-exciting a nitrogen-containing reactive gas to the substrate to form a second layer; a step of forming a film containing a predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further includes a step of supplying activated species Z generated by plasma-exciting a compound gas composed of a plurality of kinds of elements to the substrate from a side of the substrate; (b) is a substrate processing method in which the in-plane distribution of the wet etching rate of the film is adjusted by steric reaction hindrance or polarity-based desorption hindrance caused by the compound gas.

18. 18. The substrate processing method according to claim 17, wherein in (b), desorption of the halogen element from the first layer by the activated species X is inhibited by the activated species Z, and the compound gas is supplied so that a degree of inhibition in a peripheral portion of the substrate is stronger than a degree of inhibition in a central portion of the substrate.

19. (a) forming a first layer by supplying a source gas containing a predetermined element and a halogen element to a substrate; (b) generating activated species X by plasma-exciting H gas, and supplying the H gas containing the activated species X to the substrate; (c) generating activated species Y by plasma-exciting a reactive gas containing nitrogen, and supplying the reactive gas containing the activated species Y to the substrate to form a second layer; a step of forming a film containing the predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further includes a step of generating activated species Z by plasma-exciting a compound gas composed of a plurality of types of elements, and supplying the compound gas containing the activated species Z to the substrate; (b) A method for manufacturing a semiconductor device, wherein the ratio of the supply amount of the compound gas to the supply amount of H 2 gas is less than 1 / 2.

20. (a) forming a first layer by supplying a source gas containing a predetermined element and a halogen element to a substrate; (b) generating activated species X by plasma-exciting H gas, and supplying the H gas containing the activated species X to the substrate; (c) generating activated species Y by plasma-exciting a nitrogen-containing reactive gas, and supplying the reactive gas containing the activated species Y to the substrate to form a second layer; a step of forming a film containing the predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further includes a step of generating activated species Z by plasma-exciting a compound gas composed of a plurality of kinds of elements, and supplying the compound gas containing the activated species Z to the substrate; (b) a step of setting the ratio of the supply amount of the compound gas to the supply amount of H2 gas to less than 1 / 2; A program that causes a computer to execute the above in a substrate processing apparatus.

21. a source gas supply system for supplying a source gas containing a predetermined element and a halogen element to the substrate; a H2 gas supply system that supplies H2 gas to the substrate; a compound gas supply system for supplying a compound gas composed of a plurality of types of elements to the substrate; a reactive gas supply system for supplying a reactive gas containing nitrogen to the substrate; an excitation unit that excites the gas into plasma; a control unit configured to be able to control the source gas supply system, the H2 gas supply system, the compound gas supply system, the reactive gas supply system, and the excitation unit so that the ratio of the supply amount of the compound gas to the supply amount of H2 gas in (b) is less than 1 / 2; and a control unit configured to be able to control the source gas supply system, the H2 gas supply system, the compound gas supply system, the reactive gas supply system, and the excitation unit so that the ratio of the supply amount of the compound gas to the supply amount of H2 gas in (b) is less than 1 / 2; A substrate processing apparatus having: (a) supplying a source gas containing a predetermined element and a halogen element to a substrate to form a first layer; (b) supplying activated species X generated by plasma-exciting H 2 gas to the substrate; (c) supplying activated species Y generated by plasma-exciting a nitrogen-containing reactive gas to the substrate to form a second layer; a step of forming a film containing a predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further includes a step of supplying activated species Z generated by plasma-exciting a compound gas composed of a plurality of kinds of elements to the substrate; In (b), the method for manufacturing a semiconductor device includes inhibiting the desorption of the halogen element from the first layer by the active species X with the active species Z. (a) supplying a source gas containing a predetermined element and a halogen element to a substrate to form a first layer; (b) supplying activated species X generated by plasma-exciting H 2 gas to the substrate from the side of the substrate; (c) supplying activated species Y generated by plasma-exciting a nitrogen-containing reactive gas to the substrate to form a second layer; a step of forming a film containing a predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further includes a step of supplying activated species Z generated by plasma-exciting a compound gas composed of a plurality of kinds of elements to the substrate from a side of the substrate; (b) A method for manufacturing a semiconductor device, in which the in-plane distribution of the wet etching rate of the film is adjusted by steric reaction hindrance or polarity-based desorption hindrance caused by the compound gas. (a) supplying a source gas containing a predetermined element and a halogen element to a substrate to form a first layer; (b) supplying activated species X generated by plasma-exciting H 2 gas to the substrate; (c) supplying activated species Y generated by plasma-exciting a nitrogen-containing reactive gas to the substrate to form a second layer; a step of forming a film containing a predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further comprises a step of supplying activated species Z generated by plasma-exciting a compound gas composed of a plurality of kinds of elements to the substrate, and in (b), inhibiting desorption of the halogen element from the first layer by the activated species X with the activated species Z, A program executed by a computer in a substrate processing apparatus. (a) supplying a source gas containing a predetermined element and a halogen element to a substrate to form a first layer; (b) supplying activated species X generated by plasma-exciting H 2 gas to the substrate from a side of the substrate; (c) supplying activated species Y generated by plasma-exciting a nitrogen-containing reactive gas to the substrate to form a second layer; a step of forming a film containing a predetermined element and nitrogen on the substrate by performing a cycle including the steps of: (b) further comprises a step of supplying activated species Z generated by plasma-exciting a compound gas composed of a plurality of elements to the substrate from the side of the substrate, and (b) adjusting the in-plane distribution of the wet etching rate of the film by steric reaction hindrance or polarity-based desorption hindrance caused by the compound gas; A program executed by a computer in a substrate processing apparatus.

26. A source gas supply system for supplying a source gas containing a predetermined element and a halogen element to a substrate; an H 2 gas supply system that supplies H 2 gas to the substrate; a compound gas supply system for supplying a compound gas composed of a plurality of types of elements to the substrate; a reactive gas supply system for supplying a reactive gas containing nitrogen to the substrate; an excitation unit that excites the gas into plasma; a control unit configured to be able to control the source gas supply system, the H 2 gas supply system, the compound gas supply system, the reactive gas supply system, and the excitation unit so that in (b), activated species Z generated by plasma excitation of the compound gas is supplied to the substrate, and desorption of the halogen element from the first layer by the activated species X is inhibited by the activated species Z; and A substrate processing apparatus having:

27. ​​A source gas supply system for supplying a source gas containing a predetermined element and a halogen element to a substrate; an H 2 gas supply system that supplies H 2 gas to the substrate; a compound gas supply system for supplying a compound gas composed of a plurality of types of elements to the substrate; a reactive gas supply system for supplying a reactive gas containing nitrogen to the substrate; an excitation unit that excites the gas into plasma; a control unit configured to be able to control the source gas supply system, the H2 gas supply system, the compound gas supply system, the reactive gas supply system, and the excitation unit so as to adjust the in-plane distribution of the wet etching rate of the film by steric reaction hindrance or polarity hindrance of desorption caused by the compound gas in (b); and a control unit configured to be able to control the source gas supply system, the H2 gas supply system, the compound gas supply system, the reactive gas supply system, and the excitation unit so as to adjust the in-plane distribution of the wet etching rate of the film by steric reaction hindrance or polarity hindrance of desorption caused by the compound gas in (b); A substrate processing apparatus having:

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