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

Abstract

The present invention provides a technology which is capable of adjusting characteristics of a film. The present invention includes: (a) a step for supplying a first gas that contains a first element and chlorine to a substrate; (b) a step for supplying a second gas that contains iodine to the substrate; (c) a step for supplying a third gas that contains a second element to the substrate; (d) a step for forming a first film that contains the first element on the substrate by performing the steps (a) and (c) X times; and (e) a step for forming a second film that contains the first element and iodine on the substrate by performing the steps (a), (b), and (c) Y times.

Description

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

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

[0002] As part of the substrate processing process (manufacturing process for semiconductor devices), a film may be formed on the substrate by supplying a source gas containing halogen elements and a reaction gas to the substrate. (See, for example, Patent Document 1.)

[0003] International Publication No. 2019 / 058608

[0004] This disclosure provides a technology that enables the adjustment of film properties.

[0005] According to one aspect of the present disclosure, a technology is provided comprising the steps of: a) supplying a first gas containing a first element and chlorine to a substrate; b) supplying a second gas containing iodine to the substrate; c) supplying a third gas containing a second element to the substrate; d) performing steps a) and c) X times to form a first film containing the first element on the substrate; and e) performing steps a) and b) and c) Y times to form a second film containing the first element and iodine on the substrate.

[0006] According to this disclosure, it becomes possible to adjust the properties of the film.

[0007] Figure 1 is a longitudinal cross-sectional view showing the schematic of the substrate processing apparatus. Figure 2 is a schematic transverse cross-sectional view along line A-A in Figure 2. Figure 3 is a schematic configuration diagram of the controller of the substrate processing apparatus, showing the controller's control system in block diagram form. Figure 4 is a flowchart of a series of processes including the substrate processing process. Figure 5 is a flowchart of the film formation process. Figure 6 is a flowchart of the film formation process. Figure 7 is a flowchart of the film formation process. Figure 8 is a diagram showing the timing of gas supply in the film formation process.

[0008] <One Aspect of the Present Disclosure> Hereinafter, one aspect of the present disclosure will be described mainly with reference to FIGS. 1 to 8. Note that the drawings used in the following description are all schematic, and the dimensional relationships of each element shown in the drawings, the ratios of each element, etc. do not necessarily match the actual ones. Also, among the plurality of drawings, the dimensional relationships of each element, the ratios of each element, etc. do not necessarily match each other.

[0009] (1) Configuration of Substrate Processing Apparatus The substrate processing apparatus 10 includes a processing furnace 202 provided with a heater 207 as heating means (heating mechanism, heating system). The heater 207 has a cylindrical shape and is vertically installed by being supported by a heater base (not shown) as a holding plate.

[0010] Inside the heater 207, an outer tube 203 that forms a processing container concentrically with the heater 207 is disposed. The outer tube 203 is made of a heat-resistant material such as quartz or silicon carbide (SiC), and is formed in a cylindrical shape with the upper end closed and the lower end open. Below the outer tube 203, a manifold 209 (hereinafter referred to as MF209) is disposed concentrically with the outer tube 203. MF209 is made of a metal such as stainless steel and is formed in a cylindrical shape with the upper and lower ends open. An O-ring 220a as a seal member is provided between the upper end portion of MF209 and the outer tube 203. Since MF209 is supported by the heater base, the outer tube 203 is in a vertically installed state.

[0011] Inside the outer tube 203, an inner tube 204 that forms a processing container is disposed. The inner tube 204 is made of a heat-resistant material such as quartz or SiC, and is formed in a cylindrical shape with the upper end closed and the lower end open. Mainly, the processing container is constituted by the outer tube 203, the inner tube 204, and MF209. A processing chamber 201 is formed in the cylindrical hollow portion (inside the inner tube 204) of the processing container.

[0012] The processing chamber 201 is configured to be able to accommodate wafers 200 as substrates in a vertically multi-stage arrangement in a horizontal posture by a boat 217 described later.

[0013] Inside the processing chamber 201, nozzles 410, 420, 430, and 440 are provided so as to penetrate the side wall and the inner pipe 204 of the MF 209. Gas supply pipes 310, 320, 330, and 340 are respectively connected to the nozzles 410, 420, 430, and 440. However, the processing furnace 202 of the present embodiment is not limited to the above-described form.

[0014] Mass flow controllers (MFCs) 312, 322, 332, and 342, which are flow controllers (flow control units), and valves 314, 324, 334, and 344, which are on-off valves, are respectively provided in the gas supply pipes 310, 320, 330, and 340 in order from the upstream side. Gas supply pipes 510, 520, 530, and 540 for supplying an inert gas are respectively connected to the downstream sides of the valves 314, 324, 334, and 344 of the gas supply pipes 310, 320, 330, and 340. MFCs 512, 522, 532, and 542, which are flow controllers (flow control units), and valves 514, 524, 534, and 544, which are on-off valves, are respectively provided in the gas supply pipes 510, 520, 530, and 540 in order from the upstream side.

[0015] Nozzles 410, 420, 430, and 440 are respectively connected to the tip ends of the gas supply pipes 310, 320, 330, and 340. The nozzles 410, 420, 430, and 440 are configured as L-shaped nozzles, and their horizontal portions are provided so as to penetrate the side wall and the inner pipe 204 of the MF 209. The vertical portions of the nozzles 410, 420, 430, and 440 are provided inside a preliminary chamber 201a having a channel shape (groove shape) that protrudes radially outward of the inner pipe 204 and extends in the vertical direction, and are provided upward (upward in the arrangement direction of the wafers 200) along the inner wall of the inner pipe 204 in the preliminary chamber 201a.

[0016] Nozzles 410, 420, 430, and 440 are provided to extend from the lower region to the upper region of the processing chamber 201, and each has multiple gas supply holes 410a, 420a, 430a, and 440a at positions facing the wafer 200. As a result, processing gas is supplied to the wafer 200 from the gas supply holes 410a, 420a, 430a, and 440 of nozzles 410, 420, 430, and 440, respectively. Multiple gas supply holes 410a, 420a, 430a, and 440a are provided from the lower to the upper part of the inner tube 204, each having the same opening area and the same opening pitch.

[0017] The gas supply holes 410a, 420a, 430a, and 440a of the nozzles 410, 420, 430, and 440 are provided in multiple locations at a height from the bottom to the top of the boat 217, which will be described later. Therefore, the processing gas supplied into the processing chamber 201 from the gas supply holes 410a, 420a, 430a, and 440 of the nozzles 410, 420, 430, and 440 is supplied to the entire area of ​​the wafer 200 housed from the bottom to the top of the boat 217. The nozzles 410, 420, 430, and 440 only need to be provided to extend from the lower region to the upper region of the processing chamber 201, but it is preferable that they extend to near the ceiling of the boat 217.

[0018] From the gas supply pipe 310, a first element-containing gas (first gas), which includes a first element, is supplied into the processing chamber 201 via the MFC 312, valve 314, and nozzle 410 as the first material (raw material, processing gas).

[0019] From the gas supply pipe 320, the second gas is supplied into the processing chamber 201 as the first reactant (processing gas, reactant) via the MFC 322, valve 324, and nozzle 420.

[0020] From the gas supply pipe 330, a third gas is supplied into the processing chamber 201 as a second reactant (processing gas, reactant) via the MFC 332, valve 334, and nozzle 430.

[0021] From the gas supply pipe 340, a fourth gas is supplied into the processing chamber 201 as a third reactant (processing gas, reactant) via the MFC 342, valve 344, and nozzle 440. The term "agent" as used in this disclosure includes at least one of gaseous substances and liquid substances. Liquid substances include mist-like substances. That is, film-forming agents, modifiers, and etching agents may contain gaseous substances, liquid substances such as mist-like substances, or both.

[0022] From the gas supply pipes 510, 520, 530, and 540, an inert gas, such as nitrogen (N), is supplied. ２ The gases are supplied into the processing chamber 201 via MFCs 512, 522, 532, 542, valves 514, 524, 534, 544, and nozzles 410, 420, 430, 440, respectively. Hereafter, N is used as the inert gas. ２ I will now explain an example using gas, and as an inert gas, N ２ In addition to gases, noble gases such as Ar gas, He gas, Ne gas, and Xe gas may also be used.

[0023] The processing gas supply system is mainly composed of gas supply pipes 310, 320, 330, 340, MFCs 312, 322, 332, 342, valves 314, 324, 334, 344, and nozzles 410, 420, 430, 440, but the processing gas supply system may also be considered to consist only of nozzles 410, 420, 430, 440. The processing gas supply system may also be simply called the gas supply system. When the first gas is supplied from the gas supply pipe 310, the first gas supply system (first gas supply section) is mainly composed of the gas supply pipe 310, MFC 312, and valve 314, but the nozzle 410 may also be considered as part of the first gas supply system. Furthermore, when the second gas is supplied from the gas supply pipe 320, the second gas supply system (second gas supply section) is mainly composed of the gas supply pipe 320, MFC 322, and valve 324, but the nozzle 420 may also be considered as part of the second gas supply system. Furthermore, when the third gas is supplied from the gas supply pipe 330, the third gas supply system (third gas supply section) is mainly composed of the gas supply pipe 330, MFC 332, and valve 334, but the nozzle 430 may also be considered as part of the third gas supply system. When the third gas is supplied as a reaction gas from the gas supply pipe 330, the third gas supply system can also be called the reaction gas supply system. Furthermore, when the fourth gas is supplied from the gas supply pipe 340, the fourth gas supply system (fourth gas supply section) is mainly composed of the gas supply pipe 340, MFC 342, and valve 344, but the nozzle 440 may also be considered as part of the fourth gas supply system. Furthermore, the inert gas supply system is mainly composed of gas supply pipes 510, 520, 530, 540, MFCs 512, 522, 532, 542, and valves 514, 524, 534, 544.

[0024] In this embodiment, the gas is supplied via nozzles 410, 420, 430, and 440, which are located in a preliminary chamber 201a within a vertically elongated, annular space defined by the inner wall of the inner tube 204 and the edges of the multiple wafers 200. The gas is then ejected into the inner tube 204 from multiple gas supply holes 410a, 420a, 430a, and 440a, which are located on the nozzles 410, 420, 430, and 440 facing the wafers.

[0025] The exhaust port (exhaust vent) 204a is an opening formed on the side wall of the inner tube 204, opposite the nozzles 410, 420, 430, and 440. The shape of the opening is, for example, a slit shape. The gas supplied into the processing chamber 201 from the gas supply holes 410a, 420a, 430a, and 440 of the nozzles 410, 420, 430, and 440, and flowing over the surface of the wafer 200, flows through the exhaust port 204a into the exhaust passage 206, which is formed in the gap between the inner tube 204 and the outer tube 203. The gas that has flowed into the exhaust passage 206 then flows into the exhaust pipe 231 and is discharged outside the processing furnace 202.

[0026] The exhaust port 204a is provided in a position facing the plurality of wafers 200, and the gas supplied from the gas supply holes 410a, 420a, 430a, and 440a to the vicinity of the wafers 200 in the processing chamber 201 flows horizontally and then flows into the exhaust passage 206 through the exhaust port 204a. The exhaust port 204a is not limited to being configured as a slit-shaped through-hole, but may also be configured as a plurality of holes.

[0027] The MF209 is provided with an exhaust pipe 231 for exhausting the atmosphere inside the processing chamber 201. Connected to the exhaust pipe 231, in order from the upstream side, are a pressure sensor 245 as a pressure detector (pressure detection unit) for detecting the pressure inside the processing chamber 201, an APC (Auto Pressure Controller) valve 243, and a pump 246 as an exhaust device. The APC valve 243 can be opened and closed while the pump 246 is operating to exhaust and stop the atmosphere inside the processing chamber 201. Furthermore, the pressure inside the processing chamber 201 can be adjusted by adjusting the valve opening while the pump 246 is operating. The exhaust system mainly consists of the exhaust port 204a, the exhaust passage 206, the exhaust pipe 231, the APC valve 243, and the pressure sensor 245. The pump 246 may also be considered as part of the exhaust system.

[0028] Below the MF209, a seal cap 219 (hereinafter referred to as SC219) is provided, which serves as a furnace opening cover capable of airtightly closing the lower end opening of the MF209. The SC219 is configured to abut the lower end of the MF209 from the vertically downward side. The SC219 is made of a metal such as SUS and is formed in a disc shape. An O-ring 220b is provided on the upper surface of the SC219 as a sealing member that abuts the lower end of the MF209. On the opposite side of the processing chamber 201 in the SC219, a rotating mechanism 267 is installed to rotate a boat 217 that houses the wafers 200. The rotating shaft 255 of the rotating mechanism 267 passes through the SC219 and is connected to the boat 217. The rotating mechanism 267 is configured to rotate the wafers 200 by rotating the boat 217. SC219 is configured to be raised and lowered vertically by a boat elevator 115 (hereinafter referred to as BE115), which is a lifting mechanism installed vertically outside the outer tube 203. BE115 is configured to allow the boat 217 to be moved in and out of the processing chamber 201 by raising and lowering SC219. BE115 is configured as a transport device (transport system) for transporting the boat 217 and the wafers 200 contained in the boat 217 to and from the processing chamber 201.

[0029] The boat 217, which serves as a substrate support, is configured to hold multiple wafers 200, for example 10 to 200 wafers 200, in a horizontal position with vertical spacing between them. The boat 217 is made of a heat-resistant material such as quartz or SiC. At the bottom of the boat 217, a heat-insulating plate 218, also made of a heat-resistant material such as quartz or SiC, is supported in multiple stages (not shown) in a horizontal position. This configuration makes it difficult for heat from the heater 207 to be transferred to the SC 219 side. However, this embodiment is not limited to the above-described form. For example, instead of providing a heat-insulating plate 218 at the bottom of the boat 217, a heat-insulating cylinder, which is a cylindrical member made of a heat-resistant material such as quartz or SiC, may be provided.

[0030] As shown in Figure 2, a temperature sensor 263 is installed inside the inner tube 204 as a temperature detector. The amount of current supplied to the heater 207 is adjusted based on the temperature information detected by the temperature sensor 263 so that the temperature inside the processing chamber 201 reaches a desired temperature distribution. The temperature sensor 263 is configured in an L-shape, similar to the nozzles 410, 420, 430, and 440, and is installed along the inner wall of the inner tube 204.

[0031] As shown in Figure 3, the controller 121, which is the control unit (control means), is configured as a computer equipped with a CPU (Central Processing Unit) 121a, RAM (Random Access Memory) 121b, storage device 121c, and I / O port 121d. The RAM 121b, storage device 121c, and I / O port 121d are configured to exchange data with the CPU 121a via an internal bus. An input / output device 122, configured as, for example, a touch panel, is connected to the controller 121.

[0032] The storage device 121c is composed of, for example, flash memory, an HDD (Hard Disk Drive), etc. The storage device 121c contains, in a readable format, a control program that controls the operation of the substrate processing device, and a process recipe that describes the procedures and conditions for the semiconductor device manufacturing method, which will be described later. The process recipe is a combination of elements that causes the controller 121 to execute each step in the semiconductor device manufacturing method, which will be described later, and to obtain a predetermined result; it functions as a program. Hereinafter, this process recipe, control program, etc., will be collectively referred to simply as a program. In this specification, the term "program" may include only the process recipe, only the control program, or a combination of the process recipe and the control program. The RAM 121b is configured as a memory area (work area) where programs and data read by the CPU 121a are temporarily held.

[0033] The I / O port 121d is connected to the above-mentioned MFCs 312, 322, 332, 342, 512, 522, 532, 542, valves 314, 324, 334, 344, 514, 524, 534, 544, pressure sensor 245, APC valve 243, pump 246, heater 207, temperature sensor 263, rotating mechanism 267, BE115, etc.

[0034] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read recipes and other information from the storage device 121c in response to input of operation commands from the input / output device 122. The CPU 121a is configured to control the flow rate adjustment operations of various gases by MFCs 312, 322, 332, 342, 512, 522, 532, and 542, the opening and closing operations of valves 314, 324, 334, 344, 514, 524, 534, and 544, the opening and closing operations of the APC valve 243 and the pressure adjustment operations based on the pressure sensor 245 by the APC valve 243, the temperature adjustment operations of the heater 207 based on the temperature sensor 263, the starting and stopping of the pump 246, the rotation and rotation speed adjustment operations of the boat 217 by the rotating mechanism 267, the raising and lowering operations of the boat 217 by the BE 115, and the loading operations of wafers 200 into the boat 217, etc., in accordance with the contents of the read recipe.

[0035] The controller 121 can be configured by installing the above-mentioned program stored in an external storage device (for example, a magnetic disk such as a hard disk, an optical disk such as a CD or DVD, or a semiconductor memory such as flash memory) 123 onto a computer. 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. In this specification, a recording media may include only the storage device 121c, only the external storage device 123, or both. The program (program product) may be provided to the computer using communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0036] (2) Substrate Processing Process (Substrate Processing Method) An example of a process in which a first element-containing film is formed on a wafer 200 as one step in the manufacturing process of a semiconductor device is described using Figures 4, 5, 6, and 7. This process is carried out using the processing furnace 202 of the substrate processing apparatus 10 described above. In the following description, the operation of each part constituting the substrate processing apparatus 10 is controlled by the controller 121.

[0037] The substrate processing step (device manufacturing step) according to this embodiment includes: a) a step of supplying a first gas containing a first element and chlorine to a wafer 200; b) a step of supplying a second gas containing iodine to a wafer 200; c) a step of supplying a third gas containing a second element to a wafer 200; d) a step of performing steps a) and c) X times to form a first film containing the first element on the wafer 200; and e) a step of performing steps a) and c) Y times to form a second film containing the first element and iodine on the wafer 200.

[0038] In this specification, the term "wafer" may mean either "the wafer itself" or "a laminate of a wafer and a predetermined layer or film formed on its surface." In this specification, the term "surface of a wafer" may mean either "the surface of the wafer itself" or "the surface of a predetermined layer or film formed on the wafer." In this specification, the term "substrate" has the same meaning as the term "wafer."

[0039] (Wafer (substrate) loading: S101) Once multiple wafers 200 are placed on the boat 217, as shown in Figure 1, the boat 217 supporting the multiple wafers 200 is lifted by the BE 115 and loaded into the processing chamber 201 of the processing container, and then housed inside the processing container.

[0040] (Pressure and Temperature Adjustment: S102) The processing chamber 201, i.e., the space where the wafer 200 is located, is evacuated by the pump 246 to the desired pressure. At this time, the pressure inside the processing chamber 201 is measured by the pressure sensor 245, and the APC valve 243 is feedback controlled based on this measured pressure information (pressure adjustment). The pump 246 is kept running continuously at least until the processing of the wafer 200 is completed. The processing chamber 201 is also heated by the heater 207 to the desired temperature. At this time, the amount of power supplied to the heater 207 is feedback controlled based on the temperature information detected by the temperature sensor 263 so that the processing chamber 201 has the desired temperature distribution (temperature adjustment). Heating of the processing chamber 201 by the heater 207 is continued at least until the processing of the wafer 200 is completed. In the film formation process of this disclosure, the temperature of the heater 207 is set to such a temperature that the temperature of the wafer 200 is, for example, within the range of 200 to 600°C.

[0041] (Substrate processing: S103) (First film formation process: S104) In the first film formation process, the supply of the first gas and the supply of the third gas are performed X times.

[0042] (First gas supply process: S1041) The valve 314 is opened and the raw material is allowed to flow into the gas supply pipe 310. The first gas, whose flow rate has been adjusted by the MFC 312, is supplied into the processing chamber 201 from the gas supply hole 410a of the nozzle 410 and exhausted from the exhaust pipe 231.

[0043] At this time, the APC valve 243 is adjusted to set the pressure in the processing chamber 201 to a pressure within the range of, for example, 1 to 3990 Pa. The supply flow rate of the first gas controlled by the MFC 312 is set to a flow rate within the range of, for example, 0.01 to 3 slm. In this disclosure, numerical range notations such as "1 to 3990 Pa" mean that the lower limit and upper limit are included in that range. Therefore, for example, "1 to 3990 Pa" means "1 Pa or more and 3990 Pa or less". The same applies to other numerical ranges.

[0044] At this time, the first gas will be supplied to the wafer 200. By supplying the first gas to the wafer 200, a material containing the first element is adsorbed onto the wafer 200 (the underlying film on the surface). The first element includes, for example, at least one or more elements such as titanium (Ti), zirconium (Zr), hafnium (Hf), molybdenum (Mo), ruthenium (Ru), aluminum (Al), gallium (Ga), silicon (Si), germanium (Ge), etc. As the first gas, a gas containing the first element and a halogen element can be used. The halogen element is, for example, at least one or more of chlorine (Cl), fluorine (F), and bromine (Br). Such gases include, for example, WCl ６ , WF ６ , TiF ４ , MoCl ５ , MoF ５ , MoO ２ Cl ２ , RuCl ３ , RuF ３ , HfCl ４ , HfF ４ , ZrCl ４ , ZrF ４ , AlCl ３ , AlF), SiH ２ Cl ２ , Si ２ Cl ６ , etc. Among these, one or more can be used. Preferably, the raw material of the first gas contains chlorine among the halogen elements. In the present disclosure, the case where TiCl ４ is used as the raw material will be described. When TiCl ４ gas is used as the raw material, by supplying the TiCl ４ gas, TiClx (x is an integer of 4 or less) is adsorbed onto the wafer 200 (the underlying film on the surface), and the first Ti-containing layer is formed.

[0045] (Inert gas supply (purge): S1042) After a predetermined time has elapsed since the start of supplying the first gas, valve 314 is closed to stop the supply of the first gas. At this time, valves 514, 524, 534, and 544 are opened to allow inert gas to flow through the gas supply pipes 510, 520, 530, and 540 (purge). In other words, inert gas is supplied into the processing chamber 201.

[0046] At this time, the APC valve 243 is adjusted to set the pressure in the processing chamber 201 to a pressure within the range of, for example, 1 to 3990 Pa. The supply flow rates of the inert gas controlled by MFCs 512, 522, 532, and 542 are set to flow rates within the range of, for example, 0.1 to 30 slm each.

[0047] (Exhaust process: S1042) After a predetermined time has elapsed since the start of supplying the inert gas, valves 514, 524, 534, and 544 are closed to stop the supply of the inert gas. At this time, the APC valve 243 of the exhaust pipe 231 is opened, and the processing chamber 201 is evacuated using the pump 246. As a result, residual gas is removed from the wafer 200, and any remaining gases and reaction by-products in the processing chamber 201 are removed from the processing chamber 201. The time for evacuating the processing chamber 201 at this time is, for example, within the range of 0.1 to 30 seconds.

[0048] (Third gas supply process: S1043) Next, valve 334 is opened and the third gas is introduced into the gas supply pipe 330. The flow rate of the third gas is adjusted by MFC 332 and supplied into the processing chamber 201 from the gas supply hole 430a of nozzle 430, and exhausted from exhaust pipe 231.

[0049] At this time, the APC valve 243 is adjusted to set the pressure in the processing chamber 201 to a pressure within the range of, for example, 1 to 3990 Pa. The supply flow rate of the third gas controlled by the MFC 332 is set to a flow rate within the range of, for example, 0.1 to 30 slm. The time for supplying the third gas to the wafer 200 is set to a time within the range of, for example, 0.01 to 30 seconds.

[0050] At this time, a third gas is supplied to the wafer 200. Here, a reducing gas can be used as the third gas. Alternatively, for example, a nitride can be used. A nitride is a gas containing nitrogen. Specifically, NH ３ , N ２ H ２ , N ２ H ４ Gases containing nitrogen and hydrogen, such as the following, can be used. In the following, NH will be used as the third gas. ３ Let's explain an example using gas. NH ３ When supplied, it undergoes a substitution reaction with at least a portion of the Ti-containing layer formed on the wafer 200. During the substitution reaction, Ti and NH contained in the Ti-containing layer react. ３ The N contained in the gas combines to form a TiN layer on the wafer 200. Specifically, TiClx adsorbed on the wafer 200 and NH ３ The reaction forms a TiN film on the wafer 200. In addition, during the substitution reaction, HCl and ammonium chloride (NH4) are used. ４ Cl), H ２ Reaction by-products such as these are produced.

[0051] (Inert gas supply: S1044) After a predetermined time has elapsed since the start of supplying the third gas, valve 334 is closed to stop the supply of the third gas. At this time, valves 514, 524, 534, and 544 are opened to allow inert gas to flow into the gas supply pipes 510, 520, 530, and 540. In other words, inert gas is supplied into the processing chamber 201.

[0052] At this time, the APC valve 243 is adjusted to set the pressure in the processing chamber 201 to a pressure within the range of, for example, 1 to 3990 Pa. The supply flow rate of the inert gas controlled by the MFCs 512, 522, 532, and 542 is set to a flow rate within the range of, for example, 0.1 to 30 slm. At this time, the time for supplying the inert gas to the wafer 200 is set to a time within the range of, for example, 0.1 to 30 seconds.

[0053] At this time, an inert gas is supplied into the processing chamber 201. This reduces the amount of unreacted material, third gases that have contributed to film formation, and reaction by-products remaining in the processing chamber 201.

[0054] (Exhaust process: S1044) After a predetermined time has elapsed since the start of supplying the inert gas, valves 514, 524, 534, and 544 are closed to stop the supply of the inert gas. At this time, the APC valve 243 of the exhaust pipe 231 is opened and the processing chamber 201 is exhausted by the pump 246. This removes residual gas from the wafer 200 and eliminates unreacted or third gases that have contributed to film formation, as well as reaction by-products, etc., remaining in the processing chamber 201. The time for exhausting the processing chamber 201 is, for example, within the range of 0.1 to 30 seconds.

[0055] (Performed a predetermined number of times: S1045) In the first film formation process, the first gas supply process and the third gas supply process described above are performed sequentially a predetermined number of times (X times, where X is an integer of 1 or 2 or more) to form a first film of a predetermined thickness on the wafer 200. Here, for example, a titanium nitride (TiN) film is formed. The first film is a TiN film that may contain chlorine as a halogen element.

[0056] (Second film formation process: S105) In the second film formation process, the supply of the first gas S1051, the supply of the second gas S1053, and the supply of the third gas S1055 are performed Y times. These processes will be explained. Note that the supply of the first gas S1051 and the supply of the third gas S1055 are the same processes as in the first film formation process S104, so their explanation will be omitted, and the supply of the second gas S1053 will be explained.

[0057] In the second film formation step S1053, the second gas supply step S1053 is performed after the first gas supply step S1051. That is, it is performed with a layer containing the first element and a halogen formed on the surface of the wafer 200. For example, it is performed with a first Ti-containing layer formed on the surface of the wafer 200. The first Ti-containing layer is a layer containing Ti as the first element and Cl as the halogen.

[0058] (Second gas supply process S1053) The valve 324 is opened and the second gas flows into the gas supply pipe 320. The second gas, whose flow rate has been adjusted by the MFC 322, is supplied into the processing chamber 201 from the gas supply section 420a of the nozzle 420. The second gas in the processing chamber 201 is exhausted from the exhaust pipe 231.

[0059] At this time, the APC valve 243 is adjusted to set the pressure in the processing chamber 201 to a pressure within the range of, for example, 1 to 3990 Pa. The supply flow rate of the second gas controlled by the MFC 342 is set to a flow rate within the range of, for example, 0.01 to 3 slm.

[0060] At this time, a second gas is supplied to the wafer 200. The second gas is, for example, a halogen element-containing agent. The halogen elements are chlorine (Cl), fluorine (F), iodine (I), and bromine (Br). Specifically, as a halogen element-containing agent, F ２ NF ３ , Cl ２ , ClF ３ , Br ２ , I ２ , HCl, HBr, HI, BCl ３ WF ６ , WCl ６ MoCl ３ , MoCl ５These include, for example. Preferably, a gas containing an element different from the halogen contained in the first gas can be used. Specifically, if the first gas is a material containing the element chlorine, the second gas can be a gas containing iodine. Preferably, a gas that does not contain a metal element can be used. In this disclosure, an example in which HI is used as the second gas will be described. By supplying HI gas as the second gas to the wafer 200, the Cl in the Ti and Cl layer formed on the wafer 200 reacts with HI, and the Cl on the surface of the Ti-containing layer is removed from the surface of the wafer 200 as HCl. In addition, a layer containing TiIx as the second Ti-containing layer is formed on the surface of the Ti-containing layer. In this way, by supplying the second gas, at least the surface of the first Ti-containing layer can be converted into the second Ti-containing layer. The supply step of the second gas is also called the treatment step of the first Ti-containing layer. This second Ti-containing layer containing TiIx has high reactivity with the nitride agent as the third gas, and can improve the efficiency of TiN formation. Furthermore, by reacting TiClx with a nitride agent, HCl and NH are produced. ４ Although by-products such as Cl are formed, such by-products are less likely to form if TiIx is present on the surface. Furthermore, the formed TiN may contain iodine. That is, iodine-doped TiN can be formed. By adding iodine, the work function can be increased compared to iodine-free TiN films.

[0061] At this time, the valve 524 may be opened to supply an inert gas (diluting gas) from the gas supply pipe 520 to the gas supply 320, thereby diluting the second gas. The concentration (partial pressure) of the second gas can be adjusted by adjusting the flow rate of the inert gas with the MFC 522.

[0062] After supplying the second gas onto the wafer 200, the valve 324 is closed and the purging and exhaust process S1054 is performed. The purging and exhaust process S1054 is performed in the same manner as the process performed after the supply of the first gas S1041 and the supply of the third gas S1043.

[0063] After the supply process of the second gas S1053, the supply process of the third gas S1055 is performed. The procedure for the supply process of the third gas S1055 is the same as that for the supply process of the third gas S1043 described above.

[0064] (Performed a predetermined number of times: S1057) In the second film formation process, the first gas supply process, the second gas supply process, and the third gas supply process described above are performed in order a predetermined number of times (Y times, where Y is an integer of 1 or more) to form a second film of a predetermined thickness on the wafer 200. Here, for example, a titanium nitride film containing iodine is formed. Note that in the first film formation process, by-products were generated by supplying the nitride agent, but in the second film formation process, the amount of by-products generated is reduced. The by-products inhibit the adsorption of the first gas material onto the surface of the wafer 200 in the second and subsequent first gas supply processes. However, in the second film formation process, because the generation of by-products is suppressed, the inhibition of adsorption of the first gas material by by-products is less likely to occur in the second and subsequent first gas supply processes. In other words, in the second film formation process, the adsorption efficiency of the first gas material can be improved from the second predetermined number of times onward.

[0065] (Lamination of the first and second films) By laminating the first and second films, the properties of the resulting laminated film can be adjusted. Lamination of the first and second films can take the form of a first / second film structure or a second / first film structure. The first / second film structure means that the first film is formed on top of the second film. The second / first film structure means that the second film is formed on top of the first film. In this disclosure, the first and second films also include forms in which they are not complete films. Such forms include, for example, a state in which crystal nuclei are sparsely formed on the wafer 200. In other words, crystal nuclei are not densely formed on the wafer 200, that is, crystal nuclei are sparsely formed on the wafer 200. In other words, this can also be called a state in which the film is formed in an island-like manner on the wafer 200. An example of such a film is the TiN film described above.

[0066] (Formation of the second / first film) As shown in Pattern 1 of Figure 7, we will now describe the case where the second film formation step S105 is performed after the first film formation step S104. First, we will describe the case where the predetermined number of times Z is 1. When a thin film of TiN is formed on the wafer 200 as the first film, TiN crystal nuclei are formed in an island-like manner on the wafer 200. The film thickness here is, for example, 10 to 30 Å. By performing the second film formation step on the wafer 200 on which such an island-like first film has been formed, TiN can grow based on the crystal nuclei of the first film, and TiN crystals can be grown. By growing the crystals in this way, the size of the crystals can be increased. By growing crystals based on crystal nuclei, the number of grain boundaries can be reduced when the film becomes thicker. In addition, a TiN film with iodine added to the surface side of the crystal can be formed, and a TiN film with a different work function can be formed compared to TiN without iodine.

[0067] (Formation of the first / second film) As shown in Pattern 2 of Figure 7, we will now describe the case in which the first film formation step S104 is performed after the second film formation step S105. First, we will describe the case in which the predetermined number of times Z is 1. When iodine-doped TiN is formed as the second film on the outermost surface of wafer 200, crystal nuclei are formed in an island-like manner on wafer 200, but the crystal nuclei are formed more densely compared to TiN without iodine. As mentioned above, this is because the amount of by-products produced in the second film formation step is small, and the reactivity between the second Ti-containing layer and the nitride is improved. In this way, by forming the second film first, it is possible to form an iodine-doped TiN film on wafer 200 while improving the nucleus density of the film.

[0068] (Lamination of the first / second film or the second / first film) As described above, in the lamination of the first and second films, not only a two-layer structure is possible, but the formation of the first film and the formation of the second film may be performed alternately for a predetermined number of times Z. That is, in both pattern 1 and pattern 2 of Figure 7, Z is an integer of 2 or more. By forming multiple layers of the first and second films, it is possible to form an iodine-doped TiN film while promoting nucleation as described above. The amount of iodine contained in multiple laminated films (hereinafter referred to as laminated films) can be adjusted by adjusting the ratio of the predetermined number of times X in the first film formation process and the predetermined number of times Y in the second film formation process. For example, by making the predetermined number of times Y greater than the predetermined number of times X, the amount of second halogen added (e.g., the amount of iodine added) can be increased. Also, by making the predetermined number of times Y less than the predetermined number of times X, the amount of second halogen added can be decreased. Furthermore, when forming the laminated film, the characteristics of the films can be made different as described above by appropriately selecting whether the first film formed on the wafer 200 is the first film or the second film. For example, if an insulating film is formed on the surface of the wafer 200, the process is carried out in the order of second film formation → first film formation. For example, this order is carried out when the laminated film is used as the upper electrode of a capacitor. If a conductive film is formed on the surface of the wafer 200, the process is carried out in the order of first film formation → second film formation. For example, this order is carried out when the laminated film is used as the lower electrode of a capacitor. Furthermore, the ratio of the predetermined number of X and predetermined number of Y can be changed each time the predetermined number of Z is performed an arbitrary number of times. For example, by increasing the predetermined number of Y each time the predetermined number of Z is performed an arbitrary number of times, the amount of the second halogen (e.g., iodine) added to the surface side of the laminated film formed on the wafer 200 can be increased compared to the lower side of the laminated film. Conversely, by repeatedly performing the predetermined number of Z operations a predetermined number of times and decreasing the predetermined number of Y operations, the amount of the second halogen (e.g., iodine) added to the lower side of the laminated film formed on the wafer 200 can be increased compared to the surface side of the laminated film.

[0069] Furthermore, as shown by the dashed line in Pattern 1 of Figure 7, a third film formation step S108 may be performed to pre-form a third film as a seed before forming the laminated film. The third film can be formed in the same procedure as the second film described above, but the supply conditions for the second gas may be different from those in the second film formation step S105. The supply conditions for the second gas in the third film formation step S108 are conditions that improve the nuclear density formed on the wafer 200. The supply conditions for the second gas in the second film formation step S105 are conditions that mainly add iodine to the film being formed. Specifically, the amount of second gas supplied in the second film formation step S105 is greater than the amount of second gas supplied in the third film formation step. Here, the supply amount is at least one of the following: the gas supply flow rate adjusted by MFC 322, the supply time, and the concentration (partial pressure) of the second gas due to the inert gas flow rate adjusted by MFC 522. Preferably, the flow rate of the second gas and the concentration of the second gas are adjusted.

[0070] Furthermore, the process of forming the third film may be carried out using the same procedure as the second film formation process described above, but with a smaller supply amount of the second gas than in the second film formation process. This third film is, for example, provided between the first film and the second film. By forming such a third film, it is possible to form a film between the first film and the second film with a smaller amount of iodine added compared to the second film.

[0071] As described above, after forming a predetermined film on the wafer 200, a purging and atmospheric pressure return process and a wafer 200 removal process are performed.

[0072] (Purge and return to atmospheric pressure: S106) Inert gas is supplied into the processing chamber 201 from each of the gas supply pipes 510 to 540 and exhausted from the exhaust pipe 231. The inert gas acts as a purge gas, thereby purging the processing chamber 201 with the inert gas and removing any remaining gases and reaction by-products from the processing chamber 201. Subsequently, the atmosphere inside the processing chamber 201 is replaced with the inert gas, and the pressure inside the processing chamber 201 is returned to atmospheric pressure.

[0073] (Wafer (substrate) removal: S107) Subsequently, SC219 is lowered by BE115, and the lower end of the outer tube 203 is opened. Then, the processed wafer 200 is removed from the outer tube 203 through the lower end while still supported by the boat 217. After that, the processed wafer 200 is removed from the boat 217.

[0074] (3) Effects of this embodiment According to this embodiment, one or more of the following effects can be obtained: (a) By forming a film using a gas containing a second halogen element different from the first halogen element contained in the first gas (second gas: e.g., a gas containing iodine), as in the formation of the second film, the amount of by-products can be reduced. Also, by substituting the first halogen of the first gas material adsorbed on the wafer 200 with the second halogen, the reactivity with the third gas can be improved. (b) By stacking the first film and the second film, the amount of the second halogen in the film can be adjusted. As a result of adjusting the amount of the second halogen, the work function of the film formed on the wafer 200 can be adjusted. (c) By using a two-layer structure of second film / first film, TiN can be grown based on the crystal nuclei of the first film, and TiN crystals can be grown. By performing this crystal growth, the size of the crystals can be increased. By growing crystals based on crystal nuclei, the number of grain boundaries can be reduced when the film becomes thicker. Furthermore, a TiN film with iodine added to the crystal surface can be formed, and a TiN film with a different work function can be formed compared to TiN without iodine. (d) By forming a two-layer structure of the first film / second film, crystal nuclei are formed in an island-like manner on the wafer 200, but the crystal nuclei are formed more densely compared to TiN without iodine. As mentioned above, this is because the amount of by-products generated in the second film formation process is small, and the reactivity between the second Ti-containing layer and the nitride is improved. In this way, by forming the second film first, an iodine-added TiN film can be formed on the wafer 200 while improving the nucleus density of the film. (e) By stacking the first film / second film or the second film / first film, an iodine-added TiN film can be formed while promoting nucleus growth. (f) When forming a first film / second film lamination or a second film / first film lamination, the amount of second halogen (e.g., iodine) contained in the laminated film can be adjusted by adjusting the ratio of a predetermined number of times X to a predetermined number of times Y. (g) Nucleation can be performed on the wafer 200 by forming a third film before forming a first film / second film lamination or a second film / first film lamination.Furthermore, in the process of forming the lamination, a film with a second halogen added can be formed.

[0075] (4) Other Embodiments The embodiments of the present disclosure have been described in detail above. However, the present disclosure is not limited to the embodiments described above and can be modified in various ways without departing from its essence.

[0076] (Simultaneous supply of the first and fourth gases) As shown in Figure 8, the sequence may be configured to have a timing for supplying the fourth gas in parallel with the supply of the first gas. When supplying the fourth gas, the valve 344 is opened and the fourth gas flows into the gas supply pipe 340. The flow rate of the fourth gas is adjusted by the MFC 342 and supplied into the processing chamber 201 from the gas supply hole 440a of the nozzle 440, and exhausted from the exhaust pipe 231.

[0077] At this time, the APC valve 243 is adjusted to set the pressure in the processing chamber 201 to a pressure within the range of, for example, 1 to 3990 Pa. The supply flow rate of the fourth gas controlled by the MFC 332 is set to a flow rate within the range of, for example, 1 to 10 slm. The time for supplying the first gas and the fourth gas to the wafer 200 in parallel is set to a time within the range of, for example, 0.01 to 70 seconds.

[0078] At this time, the first gas and the fourth gas are supplied to the wafer 200. That is, at least the first gas and the fourth gas are supplied at the same time. As the fourth gas, for example, a gas containing at least one element from group 13 and group 14 of the periodic table and hydrogen can be used. Such a gas is, for example, SiH ４ Si ２ H ６ Si ３ H ８ Silane-based gases such as BH ３ , B ２ H ６ These are borane-based gases. In the following explanation, the fourth gas is SiH ４ This section explains when to use this method.

[0079] By supplying the fourth gas in this manner, by-products, such as hydrogen chloride (HCl), which are adsorption-inhibiting gases that inhibit film formation, are removed. Furthermore, by-products such as HCl that were adsorbed in areas where no by-products were adsorbed can be removed. As a result, adsorption sites on the wafer 200 where raw materials can be adsorbed become available, and adsorption sites where raw materials such as TiClx can be adsorbed can be formed on the surface of the wafer 200. Here, adsorption sites where raw materials can be adsorbed refer to areas on the wafer 200 where no by-products are adsorbed.

[0080] (Stopping the supply of the first gas and continuing the supply of the fourth gas) After a predetermined time has elapsed since the start of raw material supply, valve 314 is closed and the supply of the first gas is stopped. In other words, after a predetermined time has elapsed since the start of supplying the fourth gas, while the fourth gas is being supplied, the supply of the first gas is stopped in the middle of the supply of the fourth gas.

[0081] At this time, the APC valve 243 is adjusted to set the pressure in the processing chamber 201 to a pressure within the range of, for example, 1 to 3990 Pa. The time for simultaneously supplying the first gas and the fourth gas to the wafer 200 is, for example, within the range of 0.1 to 30 seconds.

[0082] At this time, the fourth gas is supplied to the wafer 200.

[0083] In this way, by stopping the supply of the first gas while the fourth gas is being supplied, and stopping the supply of the fourth gas after a predetermined time has elapsed since the first gas was stopped, the amount of by-products remaining in the processing chamber 201 can be reduced, and the film quality of the first element-containing film, such as the titanium nitride (TiN) film, can be improved.

[0084] It is preferable to supply the first and fourth gases simultaneously in the second film formation process. By doing so in the second film formation process, the suppression of by-product generation by the fourth gas and the suppression of by-product generation by the second gas can be combined to further suppress the generation of by-products. In this case, since the fourth gas reduces the x of TiClx that causes by-product generation, the second gas may enhance the effect of adding elements contained in the second gas (e.g., iodine).

[0085] Furthermore, although the above embodiment described the case in which a nitride agent is used as the third gas, this disclosure is not limited thereto, and when forming a film of a single metal instead of a nitride film on a substrate, a hydrogen-containing gas that does not contain nitrogen may be used. Examples of hydrogen-containing gases that do not contain nitrogen include H ２ Gas, deuterium (D ２ ) gases, etc. Also, when forming an oxide film, an oxidizing agent may be used. As an oxidizing agent, an oxygen-containing gas can be used. Specifically, O ２ , O ３ , H ２ O, H ２ +O ２ , H ２ O ２ , N ２ At least one of O, can be used. Furthermore, each of the nitride, reducing agent, and oxidizing agent can be a gas obtained by activating at least one of the gases of this disclosure.

[0086] It is preferable to prepare (or have multiple) process recipes (programs describing processing procedures and conditions, etc.) used for forming these various thin films, according to the content of the substrate processing (type of film to be formed, composition ratio, film quality, film thickness, processing procedure, processing conditions, etc.). When starting the substrate processing, it is preferable to appropriately select an appropriate process recipe from among the multiple process recipes according to the content of the substrate processing. Specifically, it is preferable to pre-store (install) multiple process recipes (program products) prepared individually according to the content of the substrate processing in the storage device 121c of the substrate processing apparatus via a telecommunications line or a recording medium (external storage device 123) that records the process recipes. When starting the substrate processing, it is preferable for the CPU 121a of the substrate processing apparatus to appropriately select an appropriate process recipe from among the multiple process recipes stored in the storage device 121c according to the content of the substrate processing. With this configuration, a single substrate processing apparatus can form thin films of various types, composition ratios, film quality, and film thickness in a general-purpose and reproducible manner. Furthermore, it reduces the operator's workload (such as the burden of inputting processing procedures and conditions), allowing for quicker initiation of substrate processing while avoiding operational errors.

[0087] Furthermore, this disclosure can also be implemented, for example, by changing the process recipe of an existing substrate processing apparatus. When changing the process recipe, it is possible to install the process recipe relating to this disclosure into the existing substrate processing apparatus via a telecommunications line or a recording medium on which the process recipe is stored, or to change the process recipe itself to the process recipe relating to this disclosure by operating the input / output device of the existing substrate processing apparatus.

[0088] Furthermore, this disclosure can be used, for example, in the wordline portion of NAND flash memory or DRAM having a three-dimensional structure.

[0089] Furthermore, the above embodiments and modifications describe examples of forming a film using a batch-type substrate processing apparatus that processes multiple wafers 200 at once. This disclosure is not limited to the above embodiments and can be suitably applied, for example, when forming a film using a single-wafer substrate processing apparatus that processes one or several wafers 200 at once. Furthermore, the above embodiments describe examples of forming a film using a substrate processing apparatus having a hot-wall type processing furnace. This disclosure is not limited to the above embodiments and can be suitably applied when forming a film using a substrate processing apparatus having a cold-wall type processing furnace.

[0090] In the above-described embodiments, an example was given in which the above-described processing sequence is performed in the same processing chamber of the same processing apparatus (in-situ). The present disclosure is not limited to the above-described embodiments, and for example, any step of the above-described processing sequence may be performed in different processing chambers of different processing apparatuses (ex-situ), or in different processing chambers of the same processing apparatus.

[0091] Even when using these substrate processing devices, each process can be carried out using the same processing procedures and conditions as described above, and the same effects as described above can be obtained.

[0092] The above-described embodiments and modifications can be used in combination as appropriate. The processing procedure and processing conditions in this case can be the same as, for example, the processing procedure and processing conditions of the above-described embodiments and modifications.

[0093] 200 wafers (substrates)

Claims

1. A substrate processing method comprising: a) supplying a first gas containing a first element and chlorine to a substrate; b) supplying a second gas containing iodine to the substrate; c) supplying a third gas containing a second element to the substrate; d) performing a) and c) X times to form a first film containing the first element on the substrate; and e) performing a) and b) and c) Y times to form a second film containing the first element and iodine on the substrate.

2. The substrate processing method according to claim 1, wherein step e) is performed after step d).

3. The substrate processing method according to claim 1, wherein step d) is performed after step e).

4. The substrate processing method according to claim 1, further comprising the step of performing f), d), and e) a predetermined number of times.

5. The substrate processing method according to claim 2, further comprising the step of performing f), d), and e) a predetermined number of times.

6. The substrate processing method according to claim 3, further comprising the step of performing f) e) and d) a predetermined number of times.

7. The substrate processing method according to claim 5, further comprising the step of performing e) before g) and f).

8. The substrate processing method according to claim 6, further comprising the step of performing e) before g) and f).

9. The substrate processing method according to claim 7 or 8, wherein the supply conditions for the second gas in g) and the supply conditions for the second gas in f) are different.

10. The substrate processing method according to claim 7 or 8, wherein the amount of the second gas supplied in f) is greater than the amount of the second gas supplied in g).

11. The substrate processing method according to claim 1, comprising the step of performing a), b), and c) Y2 times with a supply amount less than the supply amount of the second gas in h) and e), wherein h) is performed between e) and d).

12. A method for manufacturing a semiconductor device, comprising: a) supplying a first gas containing a first element and chlorine to a substrate; b) supplying a second gas containing iodine to the substrate; c) supplying a third gas containing a second element to the substrate; d) performing steps a) and c) X times to form a first film containing the first element on the substrate; and e) performing steps a) and b) and c) Y times to form a second film containing the first element and iodine on the substrate.

13. A program that causes a substrate processing apparatus to execute the following steps via computer: a) a procedure to supply a first gas containing a first element and chlorine to a substrate; b) a procedure to supply a second gas containing iodine to the substrate; c) a procedure to supply a third gas containing a second element to the substrate; d) a procedure to perform steps a) and c) X times to form a first film containing the first element on the substrate; e) a procedure to perform steps a) and c) Y times to form a second film containing the first element and iodine on the substrate.

14. A substrate processing apparatus comprising: a first supply unit that supplies a first gas containing a first element and chlorine to a substrate; a second supply unit that supplies a second gas containing iodine to the substrate; a third supply unit that supplies a third gas containing a second element to the substrate; and a control unit configured to control the first supply unit, the second supply unit, and the third supply unit so as to perform: a) a process of supplying the first gas to the substrate; b) a process of supplying the second gas to the substrate; c) a process of supplying the third gas to the substrate; d) a process of performing a) and c) X times to form a first film containing the first element on the substrate; and e) a process of performing a) and b) and c) Y times to form a second film containing the first element and iodine on the substrate.

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