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

Abstract

The present invention provides a technology with which it is possible to improve characteristics of a film.　The present invention includes: (a) a step for supplying a first metal-containing agent which contains a first metal to a substrate; (b) a step for supplying a first reactant which contains oxygen to the substrate; (c) a step for supplying a second reactant which contains oxygen and has an oxidizing power different from that of the first reactant to the substrate; (d) a step for forming a first layer which contains the first metal and oxygen on the substrate by performing the steps (a) and (b); and (e) a step for forming a second layer which contains the first metal and oxygen on the substrate by performing the steps (a) and (c).

Description

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

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

[0002] 2. Description of the Related Art One step in the manufacturing process of a semiconductor device is to form a film on a substrate (see, for example, Japanese Patent Application Laid-Open No. 2003-122998).

[0003] Japanese Patent Application Laid-Open No. 2008-147636

[0004] The present disclosure provides techniques that can improve film properties.

[0005] According to one aspect of the present disclosure, there is provided a technique comprising: (a) supplying a first metal-containing agent containing a first metal to a substrate; (b) supplying a first reactant containing oxygen to the substrate; (c) supplying a second reactant containing oxygen and having an oxidizing power different from that of the first reactant to the substrate; (d) performing (a) and (b) to form a first layer containing the first metal and oxygen on the substrate; and (e) performing (a) and (c) to form a second layer containing the first metal and oxygen on the substrate.

[0006] According to the present disclosure, it is possible to improve the properties of the film.

[0007] FIG. 1 is a longitudinal cross-sectional view showing an outline of a substrate processing apparatus. FIG. 2 is a schematic diagram of a controller of the substrate processing apparatus, and is a block diagram showing a control system of the controller. FIG. 3 is a series of flowcharts including a substrate processing process. FIG. 4 is a flowchart showing details of a first layer forming process and a second layer forming process. FIG. 5 is an image diagram for explaining a film formed on a substrate. FIG. 6(A) is an image diagram for explaining a first modification of a film formed on a substrate. FIG. 6(B) is an image diagram for explaining a second modification. FIG. 6(C) is an image diagram for explaining a third modification.

[0008] <One Aspect of the Present Disclosure> One aspect of the present disclosure will be described below, mainly with reference to FIGS. 1 to 5. It should be noted that all drawings used in the following description are schematic, and the dimensional relationships, ratios, etc. of the elements shown in the drawings do not necessarily correspond to the actual ones. Furthermore, the dimensional relationships, ratios, etc. of the elements between multiple drawings do not necessarily correspond to the actual ones. Furthermore, substantially identical elements between multiple drawings are assigned the same reference numerals, and each element is described in the drawing in which it first appears, and its description is omitted in subsequent drawings unless particularly necessary. Furthermore, the present disclosure is not limited to the following aspects, and can be implemented with appropriate modifications within the scope of the present disclosure.

[0009] (1) Configuration of the Substrate Processing Apparatus The substrate processing apparatus 10 includes a processing furnace 202 provided with a heater 207 as a heating unit. The heater 207 has a cylindrical shape and is installed vertically by being supported by a holding plate.

[0010] An outer tube 203 constituting a processing vessel is disposed concentrically with the heater 207 inside the heater 207. The outer tube 203 is made of a heat-resistant material such as quartz or silicon carbide and has a cylindrical shape with a closed upper end and an open lower end. A manifold 209 (hereinafter referred to as MF 209) is disposed concentrically below the outer tube 203. The MF 209 is made of a metal material such as stainless steel and has a cylindrical shape with open upper and lower ends. An O-ring 220a is provided as a sealing member between the upper end of the MF 209 and the outer tube 203. The outer tube 203 is installed vertically, similar to the heater 207.

[0011] An inner tube 204 that constitutes the processing vessel is disposed inside the outer tube 203. The inner tube 204 is made of a heat-resistant material such as quartz or silicon carbide, and is formed in a cylindrical shape with a closed upper end and an open lower end. The processing vessel is mainly constituted by the outer tube 203, the inner tube 204, and the MF 209. A processing chamber 201 is formed in the cylindrical hollow portion of the processing vessel (inside the inner tube 204).

[0012] The processing chamber 201 is configured to accommodate wafers 200 as substrates arranged in multiple stages in the vertical direction in a horizontal position on a boat 217 (described later).

[0013] Nozzles 410, 420, 430, and 440 are provided in the processing chamber 201 so as to penetrate the sidewall of the MF 209 and the inner pipe 204. Gas supply pipes 310, 320, 330, and 340 are connected to the nozzles 410, 420, 430, and 440, respectively. However, the processing furnace 202 of this embodiment is not limited to the above-mentioned configuration.

[0014] The gas supply pipes 310, 320, and 330 are respectively provided with mass flow controllers (MFCs) 312, 322, and 332, which are flow rate control devices (flow rate control parts), and valves 314, 324, and 334, which are on-off valves, in this order from the upstream side. The gas supply pipe 340 is provided with an MFC 342, an ozone (O ３ An ozonizer 600 that generates an inert gas and a valve 344 are provided. Gas supply pipes 510, 520, 530, and 540 that supply an inert gas are connected to the downstream sides of the valves 314, 324, 334, and 344 of the gas supply pipes 310, 320, 330, and 340, respectively. MFCs 512, 522, 532, and 542 and valves 514, 524, 534, and 544 are provided in the gas supply pipes 510, 520, 530, and 540, respectively, in this 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 of the MF 209 and the inner pipe 204. The vertical portions of the nozzles 410, 420, 430, and 440 are provided inside the channel-shaped (groove-shaped) pre-chamber 201a, which protrudes radially outward from the inner pipe 204 and extends vertically, and are provided in the pre-chamber 201a along the inner wall of the inner pipe 204 facing upward (upward in the arrangement direction of the wafers 200) along the inner wall of the inner pipe 204.

[0016] The nozzles 410 , 420 , 430 , and 440 are provided to extend from the lower region of the processing chamber 201 to the upper region of the processing chamber 201 , and are provided with a plurality of gas supply holes 410 a , 420 a , 430 a , and 440 a at positions facing the wafer 200 .

[0017] A first metal-containing agent containing a first metal is supplied as a processing gas from the gas supply pipe 310 into the processing chamber 201 via the MFC 312 , the valve 314 , and the nozzle 410 .

[0018] A second metal-containing agent containing a second metal is supplied as a processing gas from the gas supply pipe 320 into the processing chamber 201 via the MFC 322 , the valve 324 , and the nozzle 420 .

[0019] A first reactant (also referred to as a first reactant) containing oxygen (O) is supplied from the gas supply pipe 330 into the processing chamber 201 via an MFC 332, a valve 334, and a nozzle 430 as a reactive gas that reacts with the processing gas.

[0020] A second reactant (also referred to as a second reactant) containing O and having an oxidizing power different from that of the first reactant is supplied from the gas supply pipe 340 as a reactive gas that reacts with the processing gas into the processing chamber 201 via the MFC 342, the valve 344, and the nozzle 440.

[0021] Inert gas is supplied from gas supply pipes 510, 520, 530, and 540 into the processing chamber 201 via MFCs 512, 522, 532, and 542, valves 514, 524, 534, and 544, and nozzles 410, 420, 430, and 440, respectively.

[0022] The term "agent" as used herein includes at least one of a gaseous substance and a liquid substance. Liquid substances include mist-like substances. That is, the first metal-containing agent and the second metal-containing agent may each contain a gaseous substance, a liquid substance such as a mist-like substance, or both.

[0023] The gas supply system is mainly configured by the gas supply pipes 310, 320, 330, 340, the MFCs 312, 322, 332, 342, the valves 314, 324, 334, 344, and the nozzles 410, 420, 430, 440, but the gas supply system may also be considered to include only the nozzles 410, 420, 430, 440. When the first metal-containing agent is flowed from the gas supply pipe 310, the first metal-containing agent supply system (also referred to as a first metal supply unit or a first supply unit) is mainly configured by the gas supply pipe 310, the MFC 312, and the valve 314, but the nozzle 410 may also be considered to be included in the first metal-containing agent supply system. Furthermore, when the second metal-containing agent is flowed from the gas supply pipe 320, a second metal-containing agent supply system (also referred to as a second metal supply unit) is mainly constituted by the gas supply pipe 320, the MFC 322, and the valve 324, but the nozzle 420 may be considered to be included in the second metal-containing agent supply system. Furthermore, when the first reactant is flowed from the gas supply pipe 330, a first reactant supply system (also referred to as a first reactant supply unit, a first reactant supply unit, or a second supply unit) is mainly constituted by the gas supply pipe 330, the MFC 332, and the valve 334, but the nozzle 430 may be considered to be included in the first reactant supply system. Furthermore, when the second reactant is flowed from the gas supply pipe 340, a second reactant supply system (also referred to as a second reactant supply unit, second reactant supply unit, or third supply unit) is mainly constituted by the gas supply pipe 340, the MFC 342, and the valve 344, but the ozonizer 600 and / or the nozzle 440 may also be considered to be included in the second reactant supply system. Furthermore, an inert gas supply system (also referred to as an inert gas supply unit) is mainly constituted by the gas supply pipes 510, 520, 530, 540, the MFCs 512, 522, 532, 542, and the valves 514, 524, 534, 544.

[0024] The exhaust hole 204a is provided at a position facing the plurality of wafers 200. 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 path 206 through the exhaust hole 204a. The exhaust hole 204a is not limited to being configured as a slit-shaped through-hole, and may be configured as a plurality of holes.

[0025] The MF 209 is provided with an exhaust pipe 231 that exhausts the atmosphere inside the process chamber 201. The exhaust pipe 231 is connected to, in order from upstream, a pressure sensor 245 serving as a pressure detector (pressure detection unit) that detects the pressure inside the process chamber 201, an APC (Auto Pressure Controller) valve 243, and a pump 246 serving as an exhaust device. The APC valve 243 can exhaust or stop exhausting the atmosphere inside the process chamber 201 by opening and closing the valve while the pump 246 is operating. Furthermore, the pressure inside the process chamber 201 can be adjusted by adjusting the valve opening while the pump 246 is operating. An exhaust system is mainly composed of the exhaust hole 204a, the exhaust path 206, the exhaust pipe 231, the APC valve 243, and the pressure sensor 245. The pump 246 may be included in the exhaust system.

[0026] A seal cap 219 (hereinafter referred to as SC219) is provided below the MF209 as a furnace port cover capable of airtightly closing the lower end opening of the MF209. The SC219 is configured to abut against the lower end of the MF209 from below in the vertical direction. The SC219 is made of a metal material such as SUS and is formed in a disk shape. An O-ring 220b is provided on the upper surface of the SC219 as a sealing member that abuts against the lower end of the MF209. A rotation mechanism 267 that rotates the boat 217 is installed on the opposite side of the SC219 from the process chamber 201. A rotation shaft 255 of the rotation mechanism 267 passes through the SC219 and is connected to the boat 217. The rotation mechanism 267 is configured to rotate the boat 217 to rotate the wafers 200. The SC 219 is configured to be raised and lowered in the vertical direction by a boat elevator 115 (hereinafter referred to as BE 115) as a lifting mechanism installed vertically outside the outer tube 203. The BE 115 is configured to be able to load and unload the boat 217 into and out of the processing chamber 201 by lifting and lowering the SC 219. The BE 115 is configured as a transfer device (transfer system) that transfers the boat 217 and the wafers 200 accommodated in the boat 217 into and out of the processing chamber 201.

[0027] The boat 217, serving as a substrate support, is configured to hold multiple wafers 200, e.g., 10 to 200, arranged horizontally and with their centers aligned and spaced apart in the vertical direction. The boat 217 is made of a heat-resistant material such as quartz or silicon carbide. The lower part of the boat 217 is supported by a heat-insulating cylinder 218, which is a cylindrical member made of a heat-resistant material such as quartz or silicon carbide. This configuration makes it difficult for heat from the heater 207 to be transmitted to the SC 219. However, this embodiment is not limited to the above. For example, instead of providing the heat-insulating cylinder 218, multiple heat-insulating plates (not shown) made of a heat-resistant material such as quartz or silicon carbide may be supported horizontally at the lower part of the boat 217.

[0028] In this specification, when a numerical range such as "10 to 200 sheets" is expressed, it means that the lower limit and upper limit are included in the range. Therefore, for example, "10 to 200 sheets" means "10 sheets or more and 200 sheets or less." The same applies to other numerical ranges.

[0029] A temperature sensor 263 serving as a temperature detector is installed inside the inner pipe 204. The amount of power supplied to the heater 207 is adjusted based on temperature information detected by the temperature sensor 263, thereby achieving a desired temperature distribution inside the processing chamber 201. The temperature sensor 263 is installed along the inner wall of the inner pipe 204.

[0030] As shown in Fig. 2, 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. The controller 121 is also configured to be able to connect to an external storage device 123.

[0031] The storage device 121c is composed of, for example, a flash memory, an HDD (Hard Disk Drive), etc. The storage device 121c readably stores a control program for controlling the operation of the substrate processing apparatus, a process recipe (also simply referred to as a recipe) describing the processing procedure (procedure) and processing conditions of a semiconductor device manufacturing method (substrate processing) described later, and other information. The recipe is a combination of processes (steps) in a semiconductor device manufacturing method described later that are executed by the controller 121 to obtain a predetermined result, and functions as a program (or program product) recorded on a computer-readable recording medium. Hereinafter, the recipe, control program, etc. are collectively referred to simply as a program (or program product). In this specification, the term "program" may refer to a recipe alone, a control program alone, or a combination of a recipe and a control program. The RAM 121b is configured as a memory area (work area) for temporarily storing programs, data, etc. read by the CPU 121a.

[0032] 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, ozonizer 600, rotation mechanism 267, BE 115, etc.

[0033] The CPU 121a is configured to read and execute a control program from the storage device 121c, and also to read a recipe or the like from the storage device 121c in response to an input of an operation command from the input / output device 122 or the like. The CPU 121a is configured to be able to control, in accordance with the contents of the read recipe, the flow rate adjustment of various gases by the MFCs 312, 322, 332, 342, 512, 522, 532, and 542, the opening and closing of the valves 314, 324, 334, 344, 514, 524, 534, and 544, the opening and closing of the APC valve 243 and the pressure adjustment operation by the APC valve 243 based on the pressure sensor 245, the temperature adjustment operation of the heater 207 based on the temperature sensor 263, the adjustment of the discharge power (electricity) of the ozonizer 600, the start and stop of the pump 246, the rotation and rotation speed adjustment operation of the boat 217 by the rotation mechanism 267, the raising and lowering operation of the boat 217 by the BE 115, and the operation of storing the wafers 200 in the boat 217.

[0034] The controller 121 can be configured by installing (storing) the above-described program stored in an external storage device 123 (e.g., a magnetic disk such as a hard disk, an optical disk such as a CD or DVD, or a semiconductor memory such as a USB memory or a memory card) into a computer. The storage device 121c and the external storage device 123 are configured as computer-readable recording media on which the program is recorded. Hereinafter, these will be collectively referred to simply as recording media. In this specification, the recording medium may include only the storage device 121c, only the external storage device 123, or both. The program (or program product) 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.

[0035] (2) Substrate Processing Step (Substrate Processing Method) As one step in the manufacturing process of a semiconductor device, an example of a step of forming a metal-containing film 300 mainly on a wafer 200 will be described with reference to FIGS. 3 to 5 . This step is performed using the processing furnace 202 of the substrate processing apparatus 10 described above. In the following description, the operation of each component of the substrate processing apparatus 10 is controlled by a controller 121.

[0036] The substrate processing process (device manufacturing process) according to this embodiment includes the following steps: (a) supplying a first metal-containing agent containing a first metal to the wafer 200; (b) supplying a first reactant containing O to the wafer 200; (c) supplying a second reactant containing O and having an oxidizing power different from that of the first reactant to the wafer 200; (d) performing steps (a) and (b) to form a first layer 300a containing the first metal and O on the wafer 200; and (e) performing steps (a) and (c) to form a second layer 300b containing the first metal and O on the wafer 200.

[0037] The substrate processing step according to this embodiment also includes the step of (f) supplying a second metal-containing agent to the wafers 200, and (f) is performed in at least one of (d) and (e).

[0038] The term "wafer" used in this specification may refer to the wafer itself or to a laminate of the wafer and a predetermined layer or film formed on its surface. The term "surface of a wafer" used in this specification may refer to the surface of the wafer itself or to the surface of a predetermined layer or the like formed on the wafer. When described in this specification, "forming a predetermined layer on a wafer" may mean forming a predetermined layer directly on the surface of the wafer itself or forming a predetermined layer on a layer or the like formed on the wafer. When used in this specification, the term "substrate" is synonymous with the term "wafer".

[0039] (Substrate loading process, step S1) When multiple wafers 200 are placed on the boat 217, as shown in FIG. 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 vessel, and is accommodated in the processing vessel.

[0040] (Pressure and Temperature Adjustment Process, Step S2) The inside of the processing chamber 201, i.e., the space in which the wafers 200 are present, is evacuated by the pump 246 to a 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 in a constantly operating state at least until processing of the wafers 200 is completed. The inside of the processing chamber 201 is heated by the heater 207 to a desired temperature. At this time, the amount of power supplied to the heater 207 is feedback-controlled based on temperature information detected by the temperature sensor 263 so that the inside of the processing chamber 201 has a desired temperature distribution (temperature adjustment). Heating of the inside of the processing chamber 201 by the heater 207 continues at least until processing of the wafers 200 is completed. In the process of forming the metal-containing film 300 on the wafers 200, the wafers 200 are controlled to be maintained at a temperature of 150 to 400°C.

[0041] (First layer forming process, step S3) ((First metal-containing agent supplying process, step S301)) The valve 314 is opened, and the first metal-containing agent is allowed to flow into the gas supply pipe 310. The first metal-containing agent, the flow rate of which is adjusted by the MFC 312, is supplied into the processing chamber 201 from the gas supply hole 410a of the nozzle 410, and is exhausted from the exhaust pipe 231.

[0042] At this time, the supply amount of the first metal-containing agent is adjusted by adjusting the APC valve 243 or the MFC 312. Examples of processing conditions when supplying the first metal-containing agent include: supply flow rate of first metal-containing agent (excluding dilution gas): 0.1 to 10 g / min, more preferably 0.5 to 5 g / min, inert gas (dilution gas) supply flow rate: 100 to 100,000 sccm, more preferably 1,000 to 50,000 sccm, supply time of first metal-containing agent: 10 to 600 seconds, more preferably 30 to 300 seconds, inert gas supply flow rate (per gas supply pipe): 0 to 50,000 sccm, more preferably 5,000 to 15,000 sccm.

[0043] At this time, the first metal-containing agent is supplied to the wafer 200. As a result, the material containing the first metal is adsorbed onto the wafer 200.

[0044] The first metal-containing agent can be a gas containing molecules having a first metal and a ligand bonded to the first metal. The first metal can be a metal element, preferably a transition metal element, more preferably a Group 4 element such as titanium (Ti), zirconium (Zr), or hafnium (Hf). The ligand bonded to the first metal can be an organic ligand, preferably a hydrocarbon group containing at least one selected from the group consisting of alkyl groups such as methyl, ethyl, propyl, and butyl groups, amino groups (at least NH- groups), alkylamino groups, cyclopentadienyl groups, cyclohexadienyl groups, and cycloheptatrienyl groups. More preferably, the first metal-containing agent contains an amine group and another group.

[0045] Examples of the first metal-containing agent containing Zr as the first metal include tetrakisethylmethylaminozirconium (Zr[N(CH ３ ) C ２ H ５ ] ４ ), tetrakis(diethylamino)zirconium (Zr[N(C ２ H ５ ) ２ ] ４ ), tetrakisdimethylaminozirconium (Zr[N(CH ３ ) ２ ] ４ ), Zr(MMP) ４ , Zr(O-tBu) ４ , tris(dimethylamino)cyclopentadienyl zirconium ((C ５ H ５ )Zr[N(CH ３ ) ２ ] ３ As the first metal-containing agent, one or more of these may be used.

[0046] Furthermore, examples of the first metal-containing agent containing Hf as the first metal include tetrakisethylmethylaminohafnium (Hf[N(CH ３ ) C ２ H ５ ] ４), tetrakisdiethylaminohafnium (Hf[N(C ２ H ５ ) ２ ] ４ ), tetrakisdimethylaminohafnium (Hf[N(CH ３ ) ２ ] ４ ), Hf(O-tBu) ４ , Hf(MMP) ４ , tris(dimethylamino)cyclopentadienyl hafnium ((C ５ H ５ )Hf[N(CH ３ ) ２ ] ３ As the first metal-containing agent, one or more of these may be used.

[0047] The inert gas may be, for example, nitrogen (N ２ In addition to the above, rare gases such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, and xenon (Xe) gas can also be used. The same applies hereinafter.

[0048] ((Inert Gas Supply Process (Purge Process), Step S302)) After a predetermined time has elapsed since the start of the supply of the first metal-containing agent, the valve 314 is closed to stop the supply of the first metal-containing agent. At this time, the valves 514, 524, 534, and 544 are opened to flow an inert gas into the gas supply pipes 510, 520, 530, and 540 (purging). That is, the inert gas is supplied into the processing chamber 201.

[0049] At this time, the APC valve 243 is adjusted to set the pressure inside the processing chamber 201 within a range of, for example, 1 to 3990 Pa. The supply flow rates of the inert gases controlled by the MFCs 512, 522, 532, and 542 are set within a range of, for example, 0.1 to 30 slm, respectively.

[0050] ((Exhaust process (purging process), step S302)) After a predetermined time has elapsed since the start of the supply of inert gas, the valves 514, 524, 534, and 544 are closed, and the supply of inert gas is stopped. At this time, the APC valve 243 of the exhaust pipe 231 is opened, and the processing chamber 201 is evacuated to a vacuum by the pump 246. As a result, residual gas is removed from above the wafer 200, and gas and reaction by-products remaining in the processing chamber 201 are expelled from the processing chamber 201. This removes residual gas from above the wafer 200, and the amount of the first metal-containing agent and the amount of decomposition products remaining in the processing chamber 201 can be reduced. At this time, the time for evacuating the processing chamber 201 is set to, for example, a time within a range of 0.1 to 30 seconds.

[0051] In the purging step, at least one of the inert gas supplying step and the exhausting step is performed. The same applies hereinafter.

[0052] ((First reactant supply process, step S303)) Subsequently, the valve 334 is opened, and the first reactant is allowed to flow into the gas supply pipe 330. The flow rate of the first reactant is adjusted by the MFC 332, and the first reactant is supplied into the processing chamber 201 from the gas supply hole 430a of the nozzle 430 and exhausted from the exhaust pipe 231.

[0053] At this time, the supply amount of the first reactant is adjusted by adjusting the APC valve 243 and the MFC 332. The processing conditions for supplying the first reactant include: First reactant supply flow rate: 100 to 100,000 sccm, more preferably 1,000 to 10,000 sccm. It may also be 0.1 to 10 g / min, more preferably 0.2 to 5 g / min. Supply time: 10 to 600 seconds, more preferably 30 to 300 seconds. Inert gas supply flow rate (per gas supply pipe): 0 to 50,000 sccm, more preferably 5,000 to 15,000 sccm.

[0054] At this time, the first reactant is supplied to the wafer 200. As a result, O is adsorbed onto the material containing the first metal on the wafer 200.

[0055] The first reactant may be, for example, an oxidizing agent. The oxidizing agent may be, for example, a gas containing O or a gas containing O and hydrogen (H). The O and H containing gas may be, for example, water vapor (H ２ O gas), hydrogen peroxide (H ２ O ２ ) gas, hydrogen (H ２ ) gas + oxygen (O ２ ) Gas, H ２ Gas + ozone (O ３ ) gas, etc. can be used. As the gas containing O, for example, O ２ Gas, O ３ As the oxidizing agent, one or more of these can be used. ２ Gas + O ２ In the case of a combination of two gases, such as "gas," ２ Gas and O ２ When supplying a mixed gas, the two gases may be mixed (premixed) in a supply pipe and then supplied into the processing chamber 201, or the two gases may be supplied separately from different supply pipes into the processing chamber 201 and then mixed (postmixed) in the processing chamber 201.

[0056] ((Inert Gas Supply Process (Purge Process), Step S304)) After a predetermined time has elapsed since the start of the supply of the first reactant, the valve 334 is closed to stop the supply of the first reactant. At this time, the valves 514, 524, 534, and 544 are opened to allow the inert gas to flow into the gas supply pipes 510, 520, 530, and 540. In other words, the inert gas is supplied into the processing chamber 201.

[0057] At this time, the APC valve 243 is adjusted to set the pressure inside the processing chamber 201 within a range of, for example, 1 to 3990 Pa. The supply flow rates of the inert gases controlled by the MFCs 512, 522, 532, and 542 are set within a range of, for example, 0.1 to 30 slm. The time for which the inert gas is supplied to the wafers 200 is set within a range of, for example, 0.1 to 30 seconds.

[0058] At this time, an inert gas is supplied into the processing chamber 201. This makes it possible to reduce the first reactant and reaction by-products remaining in the processing chamber 201, which have not yet reacted or have contributed to the formation of the film.

[0059] ((Exhaust process (purging process), step S304)) After a predetermined time has elapsed since the start of the supply of the inert gas, the 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 inside of the processing chamber 201 is evacuated by the pump 246. This removes residual gas from above the wafer 200, and first reactants and reaction by-products remaining in the processing chamber 201 that have not reacted or that have contributed to film formation are removed from the processing chamber 201. At this time, the time for evacuating the inside of the processing chamber 201 is set to, for example, a time within a range of 0.1 to 30 seconds.

[0060] ((Predetermined Number of Times 1)) The above-described steps S301 to S304 are performed in order a predetermined number of times (A times, where A is 1 or an integer equal to or greater than 1). As a result, a first metal-containing layer of a predetermined thickness is formed on the wafer 200. As the first metal-containing layer, for example, a zirconium dioxide (ZrO) layer, a hafnium dioxide (HfO) layer, or the like is formed.

[0061] (Second metal-containing agent supply process, step S305) The valve 324 is opened, and the second metal-containing agent is allowed to flow into the gas supply pipe 320. The second metal-containing agent, the flow rate of which is adjusted by the MFC 322, is supplied into the processing chamber 201 from the gas supply hole 420 a of the nozzle 420, and is exhausted from the exhaust pipe 231.

[0062] At this time, the supply amount of the second metal-containing agent is adjusted by adjusting the APC valve 243 or the MFC 322. Examples of processing conditions when supplying the second metal-containing agent include: second metal-containing agent supply flow rate (excluding dilution gas): 0.1 to 10 g / min, more preferably 0.5 to 5 g / min, inert gas (dilution gas) supply flow rate: 100 to 100,000 sccm, more preferably 1,000 to 50,000 sccm, second metal-containing agent supply time: 10 to 600 seconds, more preferably 30 to 300 seconds, inert gas supply flow rate (per gas supply pipe): 0 to 50,000 sccm, more preferably 5,000 to 15,000 sccm.

[0063] At this time, the second metal-containing agent is supplied to the wafer 200. As a result, the material containing the second metal is adsorbed onto the first metal-containing layer formed on the wafer 200.

[0064] The second metal-containing agent can be a gas containing molecules having a second metal and a ligand bonded to the second metal. The second metal can be the same as the first metal or a different element, preferably a different element. The specific material for the second metal can be the same as the first metal described above.

[0065] ((Inert Gas Supply Process (Purge Process), Step S306)) After a predetermined time has elapsed since the start of the supply of the second metal-containing agent, the valve 324 is closed to stop the supply of the second metal-containing agent. At this time, the valves 514, 524, 534, and 544 are opened to flow an inert gas into the gas supply pipes 510, 520, 530, and 540 (purging). That is, the inert gas is supplied into the processing chamber 201.

[0066] At this time, the APC valve 243 is adjusted to set the pressure inside the processing chamber 201 within a range of, for example, 1 to 3990 Pa. The supply flow rates of the inert gases controlled by the MFCs 512, 522, 532, and 542 are set within a range of, for example, 0.1 to 30 slm, respectively.

[0067] ((Exhaust process (purging process), step S306)) After a predetermined time has elapsed since the start of the supply of inert gas, the valves 514, 524, 534, and 544 are closed, and the supply of inert gas is stopped. At this time, the APC valve 243 of the exhaust pipe 231 is opened, and the processing chamber 201 is evacuated to a vacuum by the pump 246. As a result, residual gas is removed from above the wafer 200, and gas and reaction by-products remaining in the processing chamber 201 are expelled from the processing chamber 201. This removes residual gas from above the wafer 200, and the amount of the second metal-containing agent and the amount of decomposition products remaining in the processing chamber 201 can be reduced. At this time, the time for evacuating the processing chamber 201 is set to, for example, a time within a range of 0.1 to 30 seconds.

[0068] ((First reactant supply step, step S307)) Subsequently, the first reactant supply step is performed in the same manner as in step S303 described above. The conditions for supplying the first reactant in this step can be set in the same manner as the conditions for supplying the first reactant in step S303 described above.

[0069] At this time, the first reactant is supplied to the wafer 200. As a result, O is adsorbed onto the material containing the second metal on the wafer 200.

[0070] ((Inert Gas Supply Step (Purge Step), Step S308)) After a predetermined time has elapsed since the start of supplying the first reactant, an inert gas supply step is performed in the same manner as the inert gas supply step of step S304 described above.

[0071] ((Evacuation Step (Purge Step), Step S308)) After a predetermined time has elapsed since the supply of the inert gas started, an evacuation step is performed in the same manner as the evacuation step of step S304 described above.

[0072] ((Predetermined Number of Times 2)) The above-described steps S305 to S308 are performed in order a predetermined number of times (B times, where B is 1 or an integer equal to or greater than 1). As a result, a second metal-containing layer of a predetermined thickness is formed on the wafer 200. As the second metal-containing layer, for example, a HfO layer, a ZrO layer, or the like is formed.

[0073] ((Predetermined Number of Times 3)) The above-described process of sequentially performing steps S301 to S304 a predetermined number of times (A times) and the process of sequentially performing steps S305 to S308 a predetermined number of times (B times) are sequentially performed a predetermined number of times (C times, where C is 1 or an integer equal to or greater than 1). As a result, a first metal-containing layer and a second metal-containing layer are stacked on the wafer 200. This stacked structure is referred to as the first layer 300a. That is, a layer containing the first metal, the second metal, and O is formed as the first layer 300a on the wafer 200. For example, a ZrO, HfO, hafnium zirconium dioxide (HZO) layer or the like is formed as the first layer 300a.

[0074] (Second Layer Formation Step, Step S4) Subsequently, the second layer formation step is performed. The second layer formation step is similar to the first layer formation step, except that the first reactant supply step is replaced by a second reactant supply step. Below, the second reactant supply step, which is different from the first layer formation step, will be described in detail, and detailed descriptions of similar steps will be omitted.

[0075] ((First Metal-Containing Agent Supplying Step, Step S401)) The first metal-containing agent supplying step is performed in the same procedure as in Step S301 described above.

[0076] ((Purge Process, Step S402)) At least one of an inert gas supply process and an exhaust process is performed in the same procedure as in step S302 described above.

[0077] (Second reactant supply process, step S403) The valve 344 is opened, and the second reactant is allowed to flow into the gas supply pipe 340. The flow rate of the second reactant is adjusted by the MFC 342, and the second reactant is supplied into the processing chamber 201 from the gas supply hole 440a of the nozzle 440 and exhausted from the exhaust pipe 231.

[0078] At this time, the supply amount of the second reactant is adjusted by adjusting the APC valve 243 and the MFC 342. The processing conditions for supplying the second reactant include: Second reactant supply flow rate: 100 to 100,000 sccm, more preferably 1,000 to 10,000 sccm. It may also be 0.01 to 10 g / min, more preferably 0.1 to 2 g / min. Supply time: 10 to 600 seconds, more preferably 30 to 300 seconds. Inert gas supply flow rate (per gas supply pipe): 0 to 50,000 sccm, more preferably 5,000 to 15,000 sccm.

[0079] At this time, the second reactant is supplied to the wafer 200. As a result, O is adsorbed onto the material containing the first metal on the first layer 300a.

[0080] The second reactant may be an oxidizing agent similar to the first reactant described above. Examples of the oxidizing agent include a gas containing O and a gas containing O and H. Examples of the gas containing O and H include H. ２ O gas, H２ O ２ Gas, H ２ Gas + O ２ Gas, H ２ Gas + O ３ The gas containing O can be, for example, O ２ Gas, O ３ Gases such as O ３ The gas is, for example, O 2 with the flow rate adjusted by MFC 342. ２ The ozonizer 600 is installed between the MFC 342 and the valve 344. ２ Oxygen is removed from the gas by the ozonizer 600. ２ O, which has a stronger oxidizing power than gas (also called a large oxidizing power) ３ Gas is generated and supplied into the processing chamber 201 via the valve 344 and the nozzle 440 .

[0081] Here, the supply conditions (supply amount, gas type) of the second reactant are set so that the oxidizing power of the second reactant is different from that of the first reactant, specifically, so that the oxidizing power of the second reactant is stronger than that of the first reactant.

[0082] For example, when the material (gas type) of the first reactant and the material of the second reactant are the same, the supply amount of the second reactant is set to be greater than the supply amount of the first reactant. Here, the supply amount is adjusted by controlling at least one of the supply flow rate and the supply time. Specifically, the supply flow rate of the second reactant is set to be greater than the supply flow rate of the first reactant. Furthermore, the supply time of the second reactant is set to be longer than the supply time of the first reactant. Furthermore, the partial pressure (concentration) of the second reactant is set to be higher than the partial pressure of the first reactant. Furthermore, the total pressure (concentration) of the second reactant is set to be higher than the total pressure of the first reactant. That is, the O concentration in the process chamber 201 in this step is set to be higher than the O concentration in the process chamber 201 in steps S303 and S307. Furthermore, O is used as the first reactant and the second reactant. ３ When gas is used, an ozonizer 600 is provided in the gas supply pipe 330 as well as in the gas supply pipe 340, and the discharge power of each ozonizer 600 is adjusted to control the amount of O ３The treatment temperature in this step is set to a second temperature higher than the first temperature in steps S303 and S307. This makes it possible to make the oxidizing power of the second reactant stronger than the oxidizing power of the first reactant.

[0083] In this specification, the processing temperature refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and the processing pressure refers to the pressure inside the processing chamber 201. Furthermore, the processing time refers to the time the processing continues. These terms also apply to the following explanations.

[0084] The oxidizing power may be adjusted by using different materials for the first reactant and the second reactant. For example, in the case of the oxidizing agent of the present disclosure, ３ Gas containing H ２ O ２ Gas, O ２ The activated gases of the present disclosure, such as plasma, have relatively stronger oxidizing power than other gases of the present disclosure. For example, O ２ , H ２ As a second reactant, at least one of O and O is used. ３ , H ２ O ２ , O ２ By using at least one of the following gases, the oxidizing power of the second reactant can be made stronger than the oxidizing power of the first reactant. ３ When gas is used, the discharge power (electricity) of the ozonizer 600 is adjusted to ３ Adjust the amount of production.

[0085] The oxidizing power may be adjusted by combining the materials and the supply conditions.

[0086] ((Purge Process, Step S404)) At least one of the inert gas supply process and the exhaust process is performed in the same procedure as described above.

[0087] ((Predetermined Number of Times 4)) The above-described steps S401 to S404 are performed in order a predetermined number of times (D times, where D is an integer of 1 or greater). As a result, a first metal-containing layer of a predetermined thickness is formed on the wafer 200. As the first metal-containing layer, for example, a ZrO or HfO layer is formed. Here, the first metal-containing layer formed in this step has a higher O content than the first metal-containing layer formed by performing the above-described steps S301 to S304 in order a predetermined number of times.

[0088] ((Second Metal-Containing Agent Supplying Step, Step S405)) The second metal-containing agent supplying step is performed in the same procedure as in Step S305 described above.

[0089] ((Purge Process, Step S406))) At least one of an inert gas supply process and an exhaust process is performed in the same procedure as in step S306 described above.

[0090] ((Second reactant supply step, step S407)) Subsequently, the second reactant supply step is carried out in the same manner as in step S403 described above.

[0091] ((Purge Process, Step S408)) At least one of the inert gas supply process and the exhaust process is carried out in the same manner as described above.

[0092] ((Predetermined Number of Times 5)) The above-described steps S405 to S408 are performed in order a predetermined number of times (E times, where E is an integer of 1 or greater). As a result, a second metal-containing layer of a predetermined thickness is formed on the wafer 200. As the second metal-containing layer, for example, a ZrO or HfO layer is formed. Here, the second metal-containing layer formed in this step has a higher O content than the second metal-containing layer formed by performing the above-described steps S305 to S308 in order a predetermined number of times.

[0093] ((Predetermined Number of Times 6)) The above-described process of sequentially performing steps S401 to S404 a predetermined number of times (D times) and the process of sequentially performing steps S405 to S408 a predetermined number of times (E times) are sequentially performed a predetermined number of times (F times, where F is an integer of 1 or greater). As a result, a first metal-containing layer and a second metal-containing layer are stacked on the first layer 300a of the wafer 200. This stacked structure is referred to as the second layer 300b. That is, a layer containing the first metal, the second metal, and O is formed as the second layer 300b on the first layer 300a. As the second layer 300b, for example, a ZrO, HfO, or HZO layer is formed. Here, the O content in the second layer 300b is greater than the O content in the first layer 300a.

[0094] 5, metal-containing film 300 is formed, which is composed of first layer 300a and second layer 300b having different O contents (also referred to as O concentrations), as shown in Fig. 5. As metal-containing film 300, for example, a ZrO, HfO, or HZO film having different O contents is formed.

[0095] (Purge and atmospheric pressure return process, step S5) An 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 gases and reaction by-products remaining in the processing chamber 201 from the processing chamber 201. Thereafter, the atmosphere in the processing chamber 201 is replaced with the inert gas, and the pressure in the processing chamber 201 is returned to atmospheric pressure.

[0096] (Substrate Unloading Process, Step S6) Thereafter, the SC 219 is lowered by the BE 115 to open the lower end of the outer tube 203. Then, the processed wafers 200 supported by the boat 217 are unloaded from the lower end of the outer tube 203 to the outside of the outer tube 203. Thereafter, the processed wafers 200 are removed from the boat 217.

[0097] 5, a conductive film 400 is formed on the outermost surface of the wafer 200 on which the metal-containing film 300 (first layer 300a and second layer 300b) has been formed. The process of forming the conductive film 400 may be performed in the same substrate processing apparatus 10 following the above-described steps S3 and S4. Alternatively, after the processed wafer 200 is unloaded, the processed wafer 200 may be transferred to a substrate processing apparatus 10 different from the substrate processing apparatus 10 that performed steps S3 and S4. As the conductive film 400, for example, a metal nitride film such as a titanium nitride (TiN) film is formed.

[0098] Here, the metal-containing film 300, such as a ZrO, HfO, or HZO film, is a high-dielectric-constant (high-k) film that has ferroelectric properties despite being a thin film. Therefore, the metal-containing film 300 may be used as a capacitor by forming conductive films 400 as electrodes on the upper and lower surfaces of the metal-containing film 300. However, if a conductive film 400 made of a material that easily causes O extraction, such as a TiN film, is formed on the upper and / or lower surfaces of the metal-containing film 300, the O contained in the metal-containing film 300 may migrate to the conductive film 400 due to an oxidation-reduction reaction at the interface. This may change the ferroelectric properties of the metal-containing film 300. Specifically, the migration of O contained in the metal-containing film 300 to the conductive film 400 may strengthen the ferroelectric properties of the metal-containing film 300. In the present disclosure, the amount of O contained in the metal-containing film 300 is adjusted by making the O content contained in the second layer 300b of the metal-containing film 300 adjacent to the conductive film 400 greater than the O content contained in the first layer 300a that is not adjacent to the conductive film 400. This makes it possible to prevent the ferroelectric properties of the metal-containing film 300 from changing due to the migration of O from the second layer 300b adjacent to the conductive film 400.

[0099] In a preferred embodiment of the present disclosure, a gas containing, for example, Hf is used as the first metal-containing agent, and a gas containing, for example, Zr is used as the second metal-containing agent. By forming an oxide film containing Hf and Zr in this manner, a ferroelectric material film with an extremely high dielectric constant can be formed. Furthermore, the oxidation conditions by the reactants in the first layer formation process and the second layer formation process may be the same or different. Alternatively, a gas containing, for example, Zr may be used as the first metal-containing agent, and a gas containing, for example, Hf may be used as the second metal-containing agent. The oxide layer containing Zr is easily crystallized and functions as a seed layer. Therefore, by forming an oxide layer containing Zr as a base, the migration of O from the oxide layer containing Zr to the conductive film 400 can be suppressed.

[0100] As described above, due to the relationship between the oxidizing power of the first reactant and the oxidizing power of the second reactant, the amount of O contained in the second layer 300b is greater than the amount of O contained in the first layer 300a. The ratio of the first metal to the second metal contained in the first layer 300a is close to the ratio of the first metal to the second metal contained in the second layer 300b. In other words, the ratio of the first metal to the second metal is approximately the same in the first layer 300a and the second layer 300b. Based on this relationship, the second layer 300b can also be referred to as an O-rich layer relative to the first layer 300a. Conversely, the first layer 300a can also be referred to as an O-poor layer relative to the second layer 300b. Furthermore, while the first layer 300a has a composition close to the stoichiometric composition, the second layer 300b can also be referred to as an O-rich layer relative to the stoichiometric composition.

[0101] The layer becomes more O-rich toward the outermost surface of metal-containing film 300. Alternatively, after first layer 300a is formed by performing first layer formation step (step S3), second layer formation step (step S4) may be performed only in the final cycle to form second layer 300b. This allows only the surface layer of metal-containing film 300 to become an O-rich layer. This embodiment also provides the same effects as the above-described embodiment.

[0102] The above-mentioned first layer forming step can be represented by the following sequence (A). The above-mentioned second layer forming step can be represented by the following sequence (B). The first layer forming step may be modified as shown in the following sequences (C) and (D). The second layer forming step may be modified as shown in the following sequences (E) and (F). In the following description, purging is omitted. The sequence may be configured so that purging is omitted. (A) [(first metal-containing agent supply → first reactant supply) × A → (second metal-containing agent supply → first reactant supply) × B] × C (B) [(first metal-containing agent supply → second reactant supply) × D → (second metal-containing agent supply → second reactant supply) × E] × F (C) (first metal-containing agent supply → first reactant supply) × C (D) (second metal-containing agent supply → first reactant supply) × C (E) (first metal-containing agent supply → second reactant supply) × F (F) (second metal-containing agent supply → second reactant supply) × F

[0103] (Modification Treatment) Before forming the conductive film 400 on the metal-containing film 300, the surface of the metal-containing film 300 may be subjected to a plasma treatment such as a plasma oxidation treatment, a plasma nitriding treatment, or a plasma hydrogenation treatment. That is, an O-containing gas, a nitrogen (N)-containing gas, an H-containing gas, or the like may be plasma-excited and supplied to the metal-containing film 300. When the conductive film 400 is formed on the metal-containing film 300, the interface of the conductive film 400 with the metal-containing film 300 is oxidized to form, for example, a titanium oxynitride (TiNO) film. By performing a plasma treatment on the surface of the metal-containing film 300 and then forming the conductive film 400 thereon, oxidation of the surface of the conductive film 400 adjacent to the metal-containing film 300 can be suppressed. That is, changes in the ferroelectric properties of the metal-containing film 300 due to migration of O from the metal-containing film 300 can be suppressed.

[0104] (3) Effects of this Aspect This aspect provides one or more of the following effects. (a) Before forming conductive film 400, the O content in second layer 300b adjacent to conductive film 400 is made greater than the O content in first layer 300a, thereby adjusting the O content in metal-containing film 300. (b) In other words, it is possible to reduce the effect of changes in film quality of metal-containing film 300 due to oxygen extraction from metal-containing film 300 by conductive film 400. (c) In other words, it is possible to suppress changes in the ferroelectric properties of metal-containing film 300 caused by adjacent conductive film 400.

[0105] (4) Other Aspects The above describes specific aspects of the present disclosure. However, the present disclosure is not limited to the above aspects and can be modified in various ways without departing from the spirit and scope of the present disclosure.

[0106] 6A shows an image of a wafer 200 according to Modification 1. In this modification, after the first layer formation process of step S3 described above is performed and before the second layer formation process of step S4 described above is performed, a third layer formation process is performed to form a third layer 300c in which the O content changes continuously. That is, a third layer 300c having an O concentration gradient is formed.

[0107] (Third Layer Formation Step) In this modified example, the third layer formation step is performed in the same manner as the first layer formation step, except that the first reactant supply step is replaced by a third reactant (also referred to as a third reactant). The third reactant may be an oxidizing agent similar to the first and second reactants described above. The oxidizing power of the third reactant is set to be stronger (also referred to as larger) than the oxidizing power of the first reactant and weaker (also referred to as smaller) than the oxidizing power of the second reactant. Furthermore, the supply conditions (supply amount, partial pressure, etc.) of the third reactant in the third reactant supply step are different for each cycle. For example, the supply conditions (supply amount, partial pressure, etc.) of the third reactant are set so that the oxidizing power of the third reactant increases with each cycle. For example, the supply amount of the third reactant is increased with each cycle, or the supply time of the third reactant is lengthened with each cycle. This modified example also achieves the same effects as the above-described embodiment.

[0108] 6B shows an image of a wafer 200 according to Modification 2. In this modification, after the first layer formation process of step S3 described above is performed, and before the second layer formation process of step S4 described above is performed, a third layer formation process is performed in which a third layer 300c in which the O content changes stepwise is formed.

[0109] (Third Layer Formation Step) In this modified example, the third layer formation step is performed in the same manner as the first layer formation step, except that the first reactant supply step is replaced by a third reactant supply step. The third reactant may be an oxidizing agent similar to the first and second reactants described above. The oxidizing power of the third reactant is set to be stronger than that of the first reactant and weaker than that of the second reactant. Furthermore, the supply conditions (supply amount, partial pressure, etc.) of the third reactant in the third reactant supply step are different for each of several cycles. For example, the supply conditions (supply amount, partial pressure, etc.) of the third reactant are set so that the oxidizing power of the third reactant increases with each of several cycles. For example, the supply amount of the third reactant is increased with each of several cycles, or the supply time of the third reactant is lengthened with each of several cycles. This modified example also achieves the same effects as the above-described embodiment.

[0110] (Variation 3) FIG. 6C shows a conceptual diagram of wafer 200 according to Variation 3. In this variation, wafer 200 having conductive film 400 formed on its surface is subjected to the second layer formation process of step S4 described above to form second layer 300b having a high O content, and then the first layer formation process of step S3 described above and the second layer formation process of step S4 described above are performed to form first layer 300a and second layer 300b. This prevents O contained in metal-containing film 300 from migrating to the conductive film 400 on the bottom and top surfaces of metal-containing film 300, which would otherwise change the electrical properties of metal-containing film 300, such as a HfO, ZrO, or HZO film. In other words, second layer 300b having a high O content is formed on the surface adjacent to conductive film 400. This prevents changes in the ferroelectric properties of metal-containing film 300.

[0111] In the above embodiments, the second layer 300b is formed on the upper surface of the first layer 300a and on the upper and lower surfaces of the first layer 300a. However, the present disclosure is not limited to this and can be suitably applied to the case where the second layer 300b is formed on the lower surface of the first layer 300a.

[0112] In the above embodiment, the first layer forming step S3 and the second layer forming step S4 include forming a first metal-containing layer and a second metal-containing layer, respectively. However, the present disclosure is not limited to this example and can be suitably applied to cases where a second metal-containing layer is formed in at least one of the first layer forming step and the second layer forming step.

[0113] In the above embodiment, the metal-containing agent and the reactant are alternately supplied. However, the present disclosure is not limited to this, and can be suitably applied to a case where the metal-containing agent and the reactant are supplied simultaneously (or partially simultaneously).

[0114] It is preferable that recipes used to form these various thin films are individually prepared (or that multiple recipes are prepared) depending on the content of the substrate processing (such as the type, composition ratio, film quality, film thickness, processing procedure, and processing conditions of the thin film to be formed). When starting substrate processing, it is preferable to appropriately select an appropriate recipe from the multiple recipes depending on the content of the substrate processing. Specifically, it is preferable that multiple recipes individually prepared depending on the content of the substrate processing are pre-stored in the storage device 121c of the substrate processing apparatus via an electric communication line or a recording medium (external storage device 123) on which the recipes are recorded. It is preferable that, when starting substrate processing, the CPU 121a of the substrate processing apparatus appropriately selects an appropriate recipe from the multiple recipes stored in the storage device 121c depending on the content of the substrate processing. This configuration enables a single substrate processing apparatus to versatilely and reproducibly form thin films with various film types, composition ratios, film quality, and film thicknesses. Furthermore, it is possible to reduce the operator's operational burden (such as the burden of inputting processing procedures and processing conditions), thereby avoiding operational errors and enabling substrate processing to be started quickly.

[0115] The present disclosure can also be realized, for example, by modifying the recipe of an existing substrate processing apparatus. When modifying the recipe, the recipe according to the present disclosure can be installed in the existing substrate processing apparatus via an electric communication line or a recording medium on which the recipe is recorded, or the recipe itself can be modified to the recipe according to the present disclosure by operating an input / output device of the existing substrate processing apparatus.

[0116] The present disclosure can also be used in, for example, a blocking layer, a charge trap layer, and a tunnel layer of a NAND flash memory having a three-dimensional structure, as well as in a capacitor layer and a gate insulating film of a DRAM.

[0117] In addition to HfO, ZrO, and HZO, the present disclosure also provides PbZnO, BaTiO ３ The present invention can also be applied to the formation of films of other materials having ferroelectric properties, such as SiO 2 , HfSiO 2 , etc. The present invention can also be applied to the formation of films of materials doped with lanthanoids, such as lanthanum (La) and yttrium (Y), into these materials.

[0118] In the above-described embodiments and modifications, an example of forming a film using a batch-type substrate processing apparatus that processes multiple wafers 200 at a time has been described. The present disclosure is not limited to the above-described embodiments and can be suitably applied, for example, to a case where a film is formed using a single-wafer substrate processing apparatus that processes one or several wafers 200 at a time. In the above-described embodiments, an example of forming a film using a substrate processing apparatus having a hot-wall processing furnace has been described. The present disclosure is not limited to the above-described embodiments and can be suitably applied to a case where a film is formed using a substrate processing apparatus having a cold-wall processing furnace.

[0119] Even when using these substrate processing apparatuses, the various processes can be performed using the same processing procedures and conditions as in the above-described embodiments and modifications, and the effects of the present disclosure can be obtained.

[0120] In the above-described embodiment, the 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 embodiment, and for example, one step and another step of the processing sequence may be performed in different processing chambers of different processing apparatuses (ex-situ), or may be performed in different processing chambers of the same processing apparatus.

[0121] The above-described embodiments and modifications may be used in combination as appropriate. The processing procedures and processing conditions in such a case may be the same as those of the above-described embodiments and modifications, for example.

[0122] 200 wafers (substrates)

Claims

1. A substrate processing method comprising the steps of: (a) supplying a first metal-containing agent containing a first metal to a substrate; (b) supplying a first reactant containing oxygen to the substrate; (c) supplying a second reactant containing oxygen and having an oxidizing power different from that of the first reactant to the substrate; (d) performing steps (a) and (b) to form a first layer containing the first metal and oxygen on the substrate; and (e) performing steps (a) and (c) to form a second layer containing the first metal and oxygen on the substrate.

2. The substrate processing method according to claim 1, wherein the concentration of oxygen contained in said second layer is higher than the concentration of oxygen contained in said first layer.

3. The substrate processing method according to claim 2, wherein the second layer is formed on at least one of the upper and lower surfaces of the first layer.

4. The substrate processing method of claim 1, wherein the supply amount of the second reactant in (e) is greater than the supply amount of the first reactant in (d).

5. The method of claim 1, wherein the partial pressure of the second reactant in (e) is higher than the partial pressure of the first reactant in (d).

6. The substrate processing method according to claim 1, wherein the second reactant is ozone, and in (c), the amount of ozone produced is adjusted by adjusting the power of an ozonizer.

7. The substrate processing method of claim 1, wherein (b) is performed at a first temperature, and (c) is performed at a second temperature higher than the first temperature.

8. The method of claim 1, wherein the first reactant and the second reactant are composed of the same material.

9. The method of claim 1, wherein the first reactant and the second reactant are composed of different materials.

10. The substrate processing method according to claim 1, wherein the substrate has a conductive film on a surface thereof, and the second layer is formed on the conductive film.

11. The substrate processing method according to claim 1, further comprising the step of forming a third layer having a continuously varying amount of oxygen after performing (d) and before performing (e).

12. The substrate processing method according to claim 1, further comprising the step of forming a third layer having a stepwise change in the amount of oxygen after performing (d) and before performing (e).

13. The substrate processing method according to claim 1, further comprising the step of (f) supplying a second metal-containing agent containing a second metal to the substrate, wherein (f) is carried out in at least one of (d) and (e).

14. The substrate processing method according to claim 1, further comprising the step of forming a conductive film on the outermost surface of the substrate.

15. A method for manufacturing a semiconductor device, comprising the steps of: (a) supplying a first metal-containing agent containing a first metal to a substrate; (b) supplying a first reactant containing oxygen to the substrate; (c) supplying a second reactant containing oxygen and having an oxidizing power different from that of the first reactant to the substrate; (d) performing steps (a) and (b) to form a first layer containing the first metal and oxygen on the substrate; and (e) performing steps (a) and (c) to form a second layer containing the first metal and oxygen on the substrate.

16. A program that causes a substrate processing apparatus to execute, by a computer, the following steps: (a) supplying a first metal-containing agent containing a first metal to a substrate; (b) supplying a first reactant containing oxygen to the substrate; (c) supplying a second reactant containing oxygen and having an oxidizing power different from that of the first reactant to the substrate; (d) performing steps (a) and (b) to form a first layer containing the first metal and oxygen on the substrate; and (e) performing steps (a) and (c) to form a second layer containing the first metal and oxygen on the substrate.

17. A substrate processing apparatus comprising: a first supply unit that supplies a first metal-containing agent containing a first metal to a substrate; a second supply unit that supplies a first reactant containing oxygen to the substrate; a third supply unit that supplies a second reactant containing oxygen and having an oxidizing power different from that of the first reactant to the substrate; and a control unit configured to be able to control the first supply unit, the second supply unit, and the third supply unit to perform the following processes: (a) a process of supplying the first metal-containing agent to the substrate; (b) a process of supplying the first reactant to the substrate; (c) a process of supplying the second reactant to the substrate; (d) a process of performing (a) and (b) to form a first layer containing the first metal and oxygen on the substrate; and (e) a process of performing (a) and (c) to form a second layer containing the first metal and oxygen on the substrate.

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