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

Abstract

The present disclosure provides a technique whereby it is possible to improve step coverage during film formation. According to one embodiment, provided is a technique involving: (a1) a step for modifying at least a part of a substrate by supplying a first modifying gas to the substrate; (a2) a step for supplying a first process gas containing a first element to the substrate, and preferentially adsorbing the first element in a region not modified by the first modifying gas; (b1) a step for modifying at least a part of the substrate by supplying, to the substrate, a second modifying gas having a decomposition temperature different from that of the first modifying gas; and (b2) a step for supplying a second process gas containing a second element to the substrate, and preferentially adsorbing the second element in a region not modified by the second modifying gas.

Description

Technical Field

[0001] The present disclosure is a technology effective when applied to a substrate processing method, a method for manufacturing a semiconductor device, a substrate processing apparatus, and a program.

Background Art

[0002] With the miniaturization and complexity of device shapes in recent LSI manufacturing processes, finer processing technologies have been demanded (see, for example, Patent Document 1 and Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] The present disclosure provides a technology for improving step coverage and embedding characteristics in film formation.

[0005] Other problems and novel features will become apparent from the description of this specification and the accompanying drawings.

Means for Solving the Problems

[0006] According to a typical embodiment of the present disclosure, (a1) a step of supplying a first reforming gas to a substrate to reform at least a part of the substrate; and (a2) a step of supplying a first processing gas containing a first element to the substrate to preferentially adsorb the first element in a region not reformed by the first reforming gas. A first film formation step comprising forming a first film containing the aforementioned first element, (b1) A step of supplying a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate to reform at least a portion of the substrate, (b2) A step of supplying a second processing gas containing the second element to the substrate so that the second element is preferentially adsorbed in the areas that have not been modified by the second modification gas, A second film formation step comprising forming a second film containing the second element using the first film as a seed film, Technology possessing this is provided. [Effects of the Invention]

[0007] This disclosure can improve step coverage and embedding characteristics in film formation. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a longitudinal cross-sectional view of a substrate processing apparatus according to an embodiment. [Figure 2] Figure 2 is a block diagram showing the configuration of the controller in the substrate processing apparatus shown in Figure 1. [Figure 3] Figure 3 shows a first substrate processing method according to an embodiment. [Figure 4] Figure 4 shows a second substrate processing method according to the embodiment. [Figure 5] Figure 5 shows the configuration of the gas supply piping system used in the second substrate processing method. [Figure 6] Figure 6 illustrates the film formation process using the first reformed gas. [Figure 7] Figure 7(a) shows the adsorption sites of the first reformed gas. Figure 7(b) shows the adsorption sites of the second reformed gas. [Figure 8] Figure 8(a) shows the adsorption sites of the first reformed gas in the first film deposition step. Figure 8(b) shows the film formed in the first film deposition step. Figure 8(c) shows the adsorption sites of the second reformed gas in the second film deposition step. Figure 8(d) shows the film formed in the second film deposition step. [Modes for carrying out the invention]

[0009] Embodiments will be described below with reference to the drawings. However, in the following description, the same reference numerals will be used for the same components, and repeated explanations may be omitted. In addition, the drawings may be more schematic than the actual embodiments in order to make the explanation clearer, but they are merely examples and do not limit the interpretation of this disclosure. Furthermore, all drawings used in the following description are schematic, and the dimensional relationships and ratios of each element shown in the drawings may not necessarily match those of reality. Furthermore, the dimensional relationships and ratios of each element may not necessarily match between multiple drawings.

[0010] (1) Configuration of substrate processing apparatus Figure 1 is a schematic diagram of the vertical processing furnace of the substrate processing apparatus according to the present disclosure, and is a vertical cross-sectional view of the processing furnace portion. As shown in Figure 1, the processing furnace 202 has a heater 207 as a heating mechanism (temperature control unit). The heater 207 is cylindrical and is mounted vertically by being supported by a holding plate. The heater 207 also functions as an activation mechanism (excitation unit) that activates (excites) the gas with heat.

[0011] Inside the heater 207, a reaction tube 203 is arranged concentrically with the heater 207. The reaction tube 203 is made of a heat-resistant material such as quartz (SiO2) or silicon carbide (SiC), and is formed in a cylindrical shape with a closed upper end and an open lower end. Below the reaction tube 203, a manifold 209 is arranged concentrically with the reaction tube 203. The manifold 209 is made of a metal material such as stainless steel (SUS), and is formed in a cylindrical shape with open upper and lower ends. The upper end of the manifold 209 engages with the lower end of the reaction tube 203 and is configured to support the reaction tube 203. An O-ring 220a is provided between the manifold 209 and the reaction tube 203 as a sealing member. The reaction tube 203 is installed vertically, similar to the heater 207. The processing vessel (reaction vessel) is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed in the hollow cylindrical portion of the processing container. The processing chamber 201 is configured to accommodate a wafer 200 as a substrate. Processing of the wafer 200 is performed within this processing chamber 201.

[0012] Within the processing chamber 201, nozzles 249a to 249e, which serve as the first to fifth supply units, are provided so as to penetrate the side walls of the manifold 209. Figure 1 shows three nozzles, 249a to 249c, while the other two nozzles, 249d to 249e, are omitted from the drawing to avoid complicating the diagram. Nozzles 249a to 249e are also referred to as the first to fifth nozzles. Nozzles 249a to 249e are made of a heat-resistant material such as quartz or SiC. Gas supply pipes 232a to 232e are connected to nozzles 249a to 249e, respectively. Nozzles 249a to 249e are all different nozzles.

[0013] In the gas supply pipes 232a to 232e, mass flow controllers (MFCs) 241a to 241e, which are flow rate controllers (flow rate control units), and valves 243a to 243e, which are on-off valves, are provided in order from the upstream side of the gas flow. On the downstream side of the valves 243a to 243e of the gas supply pipes 232a to 232e, gas supply pipes 232f to 232j are respectively connected. In the gas supply pipes 232f to 232j, MFCs 241f to 241j and valves 243f to 243j are provided in order from the upstream side of the gas flow. The gas supply pipes 232a to 232j are made of a metal material such as SUS, for example.

[0014] Nozzles 249a to 249e are respectively provided in an annular space in a plan view between the inner wall of the reaction tube 203 and the wafer 200, rising upward along the upper part from the lower part of the inner wall of the reaction tube 203 in the direction above the arrangement direction of the wafer 200. That is, nozzles 249a to 249e are respectively provided along the wafer arrangement area in an area horizontally surrounding the wafer arrangement area on the side of the wafer arrangement area where the wafer 200 is arranged. For example, in a plan view, the nozzle 249c is arranged to face the exhaust port 231a described later in a straight line across the center of the wafer 200 carried into the processing chamber 201. The nozzles 249a, 249b and the nozzles 249d, 249e are arranged so as to sandwich the straight line passing through the centers of the nozzle 249c and the exhaust port 231a from both sides along the inner wall of the reaction tube 203 (the outer peripheral part of the wafer 200). The straight line is also a straight line passing through the centers of the nozzle 249c and the wafer 200. That is, it can also be said that the nozzle 249c is provided on the opposite side of the nozzle 249a across the straight line L. The nozzles 249a, 249b and the nozzles 249d, 249e are arranged symmetrically with the straight line as the axis of symmetry. Gas supply holes 250a to 250d for supplying gas are respectively provided on the side surfaces of the nozzles 249a to 249e. The gas supply holes 250a to 250d are each opened so as to face (face) the exhaust port 231a in a plan view, and it is possible to supply gas toward the wafer 200. A plurality of gas supply holes 250a to 250d are provided from the lower part to the upper part of the reaction tube 203.

[0015] From the gas supply pipe 232a, as the first processing gas (first raw material gas) containing the first element, for example, a Si-containing gas containing silicon (Si) as the first element can be used. As the Si-containing gas, for example, silane gas containing Si as the main element is supplied into the processing chamber 201 through the MFC241a, the valve 243a, and the nozzle 249a.

[0016] From the gas supply pipe 232b, a first reforming gas (first film formation inhibiting gas, first inhibitor), such as a gas containing Si as the first element and a halogen element, i.e., halosilane gas, is supplied into the processing chamber 201 via the MFC 241b, valve 243b, and nozzle 249b.

[0017] From the gas supply pipe 232c, a silane gas containing Si as the second element, for example, is supplied into the processing chamber 201 as a second processing gas (second raw material gas) containing the second element, via the MFC 241c, valve 243c, and nozzle 249c.

[0018] From the gas supply pipe 232d, a second reforming gas (second film formation inhibiting gas, second inhibitor), such as a gas containing Si as a second element and a halogen element, i.e., halosilane gas, is supplied into the processing chamber 201 via the MFC 241d, valve 243d, and nozzle 249d.

[0019] From the gas supply pipe 232e, the reaction gas is supplied into the processing chamber 201 via the MFC 241e, valve 243e, and nozzle 249e.

[0020] From gas supply pipes 232f to 232j, an inert gas, such as nitrogen (N2) gas, is supplied into the processing chamber 201 via MFCs 241f to 241j, valves 243f to 243j, and nozzles 249a to 249e, respectively. The inert gas acts as a purge gas, carrier gas, diluent gas, etc.

[0021] The supply system for the first processed gas (first raw material gas) mainly consists of gas supply pipe 232a, MFC 241a, and valve 243a. The supply system for the first reformed gas mainly consists of gas supply pipe 232b, MFC 241b, and valve 243b. The supply system for the second processed gas (second raw material gas) mainly consists of gas supply pipe 232c, MFC 241c, and valve 243c. The supply system for the second reformed gas mainly consists of gas supply pipe 232d, MFC 241d, and valve 243d. The supply system for the reaction gas mainly consists of gas supply pipe 232e, MFC 241e, and valve 243e. The supply system for the inert gas mainly consists of gas supply pipes 232f to 232j, MFC 241f to 241j, and valves 243f to 243j.

[0022] Of the various supply systems described above, one or all of them may be configured as an integrated supply system 248, which is comprised of valves 243a to 243j and MFCs 241a to 241j. The integrated supply system 248 is connected to each of the gas supply pipes 232a to 232j, and the supply operation of various gases into the gas supply pipes 232a to 232j, i.e., the opening and closing operation of valves 243a to 243j and the flow rate adjustment operation by MFCs 241a to 241j, is controlled by a controller 121, which will be described later. The integrated supply system 248 is configured as an integrated or segmented integrated unit, and can be attached to and detached from the gas supply pipes 232a to 232j, etc., in units of the integrated unit, and is configured so that maintenance, replacement, and expansion of the integrated supply system 248 can be performed in units of the integrated unit.

[0023] An exhaust port 231a for exhausting the atmosphere inside the processing chamber 201 is provided at the lower part of the side wall of the reaction tube 203. The exhaust port 231a is located opposite (facing) the nozzles 249a to 249e (gas supply holes 250a to 250e) with the wafer 200 in between. The exhaust port 231a may also be provided along the upper part of the side wall of the reaction tube 203, that is, along the wafer arrangement region. An exhaust pipe 231 is connected to the exhaust port 231a. A vacuum pump 246, which is a vacuum evacuation device, is connected to the exhaust pipe 231 via a pressure sensor 245, which is a pressure detector (pressure detection unit) for detecting the pressure inside the processing chamber 201, and an APC (Auto Pressure Controller) valve 244, which is a pressure regulator (pressure adjustment unit). The APC valve 244 can be opened and closed while the vacuum pump 246 is operating to evacuate and stop the vacuum evacuation in the processing chamber 201. Furthermore, while the vacuum pump 246 is operating, the valve opening can be adjusted based on the pressure information detected by the pressure sensor 245 to adjust the pressure in the processing chamber 201. The exhaust system mainly consists of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 may also be considered as part of the exhaust system.

[0024] Below the manifold 209, a seal cap 219 is provided as a furnace opening cover capable of airtightly closing the lower end opening of the manifold 209. The seal cap 219 is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220b is provided on the upper surface of the seal cap 219 as a sealing member that contacts the lower end of the manifold 209. Below the seal cap 219, a rotating mechanism 267 for rotating the boat 217, which will be described later, is installed. The rotating shaft 255 of the rotating mechanism 267 passes through the seal cap 219 and is connected to the boat 217. The rotating mechanism 267 is configured to rotate the wafer 200 by rotating the boat 217. The seal cap 219 is configured to be raised and lowered vertically by a boat elevator 115, which is installed outside the reaction tube 203 as a lifting mechanism. The boat elevator 115 is configured as a transport device (transport mechanism) that moves wafers 200 into and out of the processing chamber 201 by raising and lowering the seal cap 219. Below the manifold 209, a shutter 219s is provided as a furnace opening cover that can airtightly close the lower end opening of the manifold 209 when the seal cap 219 has been lowered and the boat 217 has been moved out of the processing chamber 201. The shutter 219s is made of a metal material such as SUS and is formed in a disc shape. An O-ring 220c is provided on the upper surface of the shutter 219s as a sealing member that contacts the lower end of the manifold 209. The opening and closing operation of the shutter 219s (such as raising and lowering or rotating) is controlled by the shutter opening and closing mechanism 115s.

[0025] The boat 217, which serves as a substrate support, is configured to support multiple wafers 200, for example 25 to 200 wafers 200, in a horizontal position and aligned vertically with their centers aligned, in multiple layers, that is, arranged with spacing between them. The boat 217 is made of a heat-resistant material such as quartz or SiC. Below the boat 217, multiple layers of heat-insulating plates 218, also made of a heat-resistant material such as quartz or SiC, are supported.

[0026] In this specification, numerical ranges such as "25 to 200 sheets" mean that the lower and upper limits are included within that range. Therefore, for example, "25 to 200 sheets" means "25 sheets or more and 200 sheets or less." The same applies to other numerical ranges.

[0027] A temperature sensor 263 is installed inside the reaction tube 203 as a temperature detector. By adjusting the amount of power supplied to the heater 207 based on the temperature information detected by the temperature sensor 263, the temperature inside the processing chamber 201 is adjusted to the desired temperature distribution. The temperature sensor 263 is installed along the inner wall of the reaction tube 203.

[0028] As shown in Figure 2, 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 121e. An input / output device 122, configured as, for example, a touch panel, is connected to the controller 121.

[0029] 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, control programs that control the operation of the board processing device, and process recipes that describe the procedures and conditions for board processing, as described later. The process recipe is a combination of steps in the board processing described later that cause the controller 121 to execute and obtain predetermined results; it functions as a program. Hereinafter, process recipes and control programs will be collectively referred to simply as "programs." Similarly, process recipes will be referred to simply as "recipes." In this specification, the term "program" may include only recipes, only control programs, or both. The RAM 121b is configured as a memory area (work area) where programs and data read by the CPU 121a are temporarily held.

[0030] I / O port 121d is connected to the MFCs 241a to 241j, valves 243a to 243j, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotary mechanism 267, boat elevator 115, shutter opening / closing mechanism 115s, etc.

[0031] The CPU 121a is configured to read and execute a control program from the storage device 121c, and to read a recipe from the storage device 121c in response to 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 the MFCs 241a to 241j, the opening and closing operations of valves 243a to 243j, the opening and closing operations of the APC valve 244 and the pressure adjustment operations of the APC valve 244 based on the pressure sensor 245, the starting and stopping of the vacuum pump 246, the temperature adjustment operations of the heater 207 based on the temperature sensor 263, 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 boat elevator 115, and the opening and closing operations of the shutter 219s by the shutter opening and closing mechanism 115s, in accordance with the contents of the read recipe.

[0032] The controller 121 can be configured by installing the above-mentioned program stored in the external storage device 123 onto a computer. The external storage device 123 includes, for example, magnetic disks such as HDDs, optical disks such as CDs, magneto-optical disks such as MOs, and semiconductor memory such as USB memory. 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, the term recording media may include only the storage device 121c, only the external storage device 123, or both. Note that the program may be provided to the computer using communication means such as the Internet or a dedicated line, without using the external storage device 123.

[0033] (2) Substrate processing process (2-1) First substrate processing method Figure 3 shows a first substrate processing method according to an embodiment. As one step in the manufacturing method of a semiconductor device, an example of a substrate processing method in which a film containing a first element (first film, first layer) and a film containing a second element (second film, second layer) are formed on a wafer 200 will be explained using Figure 3. In this example, the process involves forming a film containing a first element and a film containing a second element inside a recess formed on the surface of the wafer 200, and is performed using the processing furnace 202 of the substrate processing apparatus 10 described above. In the following explanation, the operation of each part constituting the substrate processing apparatus 10 is controlled by the controller 121.

[0034] The substrate processing step (semiconductor manufacturing step) according to this embodiment is, for example, (a1) A step of supplying a first modifying gas (first film formation inhibiting gas, first inhibitor) to a substrate (wafer 200) to modify at least a portion of the substrate, (a2) A step of supplying a first processing gas (first raw material gas) containing the first element to the substrate, thereby preferentially adsorbing the first element to the regions that have not been reformed by the first reforming gas, (b1) A step of supplying a second reforming gas (second film formation inhibiting gas, second inhibitor) having a different decomposition temperature from the first reforming gas to the substrate, thereby reforming at least a portion of the substrate. (b2) A step of supplying a second processing gas (second raw material gas) containing the second element to the substrate to preferentially adsorb the second element in areas that have not been modified by the second reforming gas, It has.

[0035] In this specification, the term "wafer" may mean "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 "the surface of the wafer itself" or "the surface of a predetermined layer or film formed on the wafer." In this specification, the phrase "form a predetermined layer on a wafer" may mean directly forming a predetermined layer on the surface of the wafer itself or forming a predetermined layer on top of a layer already formed on the wafer. In this specification, the term "substrate" has the same meaning as the term "wafer."

[0036] In this specification, processing temperature refers to the temperature of the wafer 200 or the temperature inside the processing chamber 201, and processing pressure refers to the pressure inside the processing chamber 201. Processing time refers to the duration for which the processing is continued. These terms also apply in the following description.

[0037] (Circuit board delivery process) During the substrate loading process, wafer charging and boat loading, as well as pressure and temperature adjustment, are performed.

[0038] (Wafer charge and boat load) When multiple wafers 200 are loaded into the boat 217 (wafer charging), the shutter 219s is moved by the shutter opening / closing mechanism 115s, opening the lower end opening of the manifold 209 (shutter opening). Then, as shown in Figure 1, the boat 217 supporting the multiple wafers 200 is lifted by the boat elevator 115 and transported into the processing chamber 201 (boat loading). In this state, the seal cap 219 seals the lower end of the manifold 209 via the O-ring 220b.

[0039] (Pressure adjustment and temperature adjustment) The processing chamber 201, i.e., the space where the wafer 200 is located, is evacuated (reduced pressure exhaust) by a vacuum pump 246 to achieve a desired pressure (vacuum level). At this time, the pressure inside the processing chamber 201 is measured by a pressure sensor 245, and the APC valve 244 is feedback-controlled based on this measured pressure information. The wafer 200 inside the processing chamber 201 is also heated by a heater 207 to reach a desired processing temperature. At this time, the amount of power supplied to the heater 207 is feedback-controlled based on the temperature information detected by a temperature sensor 263 to ensure a desired temperature distribution inside the processing chamber 201. The rotation of the wafer 200 is also started by a rotation mechanism 267. The exhaust of the processing chamber 201, the heating of the wafer 200, and the rotation are all continued at least until the processing of the wafer 200 is completed.

[0040] (First film deposition step: S1) Next, the first film deposition step S1 is performed. In the first film deposition step S1, the following steps (processes) are executed.

[0041] (Step a1) In this step, a first reforming gas is supplied to the wafer 200 in the processing chamber 201 to reform at least a portion of the wafer 200.

[0042] Specifically, valve 243b is opened, and the first reformed gas flows into the gas supply pipe 232b. The flow rate of the first reformed gas is adjusted by MFC 241b, supplied into the processing chamber 201 via nozzle 249b, and exhausted from exhaust port 231a. At this time, the first reformed gas is supplied to the wafer 200 (first reformed gas supply step). Also at this time, valves 243f, 243h, 243i, and 243j are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a, 249c, 249d, and 249e, respectively.

[0043] (Purge step sp1) Subsequently, valve 243b is closed to stop the supply of the first reformed gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gases and other substances from within the processing chamber 201. At this time, valves 243f to 243j are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a to 249e. The N2 gas supplied from nozzles 249a to 249e acts as a purge gas, thereby purging the processing chamber 201.

[0044] (Step a2) After step a1 is completed, a first processing gas (first raw material gas) is supplied to the surface of the wafer 200 in the processing chamber 201. On the surface of the wafer 200, the adsorption of the first processing gas is inhibited in areas where the first modifying gas was adsorbed in step a1. In other words, in this step, a first processing gas containing the first element is supplied to the wafer 200, and the first element is preferentially adsorbed in areas of the wafer 200 that have not been modified by the first modifying gas.

[0045] Specifically, valve 243a is opened, and the first processing gas flows into the gas supply pipe 232a. The flow rate of the first processing gas is adjusted by MFC 241a, supplied into the processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, the first processing gas is supplied to the wafer 200 (first processing gas supply step). Also at this time, valves 243g to 243i are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249b to 249d, respectively.

[0046] (Purge step sp2) After nuclei are formed on the surface of the wafer 200, valve 243a is closed to stop the supply of the first processing gas into the processing chamber 201. Then, any remaining gases and other substances in the processing chamber 201 are removed from the processing chamber 201 using the same processing procedure as in the purging step sp1.

[0047] [Step sc1: Performed a predetermined number of times] By performing the above steps a1 and a2 alternately, i.e., non-simultaneously without synchronization, a predetermined number of cycles (n1 times, where n1 is an integer of 1 or more), a film containing the first element can be formed on the wafer 200.

[0048] In the first film deposition step, the thickness of the film containing the first element formed on the wafer 200 can be controlled by controlling at least one of the following processing temperatures and processing times (first reforming gas, first processing gas supply time). Furthermore, in the first film deposition step, the thickness of the film containing the first element formed on the wafer 200 can also be controlled by controlling the number of cycles performed as described above.

[0049] The processing conditions in step a1 are: First reformed gas supply flow rate: 10-1000 sccm First reformed gas supply time: 0.5-10 minutes N2 gas supply flow rate (per gas supply pipe): 10-10000 sccm Processing temperature (first temperature): 350~420℃ Processing pressure: 100~1000Pa Examples are given.

[0050] The processing conditions in step a2 are: First treatment gas supply flow rate: 10-1000 sccm First processing gas supply time: 0.5-10 minutes This is an example. Other processing conditions are the same as the processing conditions in step a1.

[0051] (Temperature rise step st1: Temperature adjustment step) After a film containing the first element is formed on the wafer 200, the output of the heater 207 is adjusted to change the temperature inside the processing chamber 201, i.e., the temperature of the wafer 200, to a second temperature higher than the first temperature described above. When performing this step, valves 243f to 243j are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a to 249e and exhausted from exhaust port 231a to purge the processing chamber 201. After the temperature of the wafer 200 reaches the second temperature and stabilizes, the second film deposition step described later is started.

[0052] (Second film deposition step: S2) Next, the second film deposition step S2 is performed. In the second film deposition step S2, the following steps (processes) are executed.

[0053] (Step b1) In this step, a second reforming gas, having a different decomposition temperature from the first reforming gas, is supplied to the wafer 200 in the processing chamber 201, that is, to the surface of the film containing the first element formed on the wafer 200, thereby reforming at least a portion of the substrate. Here, we will explain using the case where the decomposition temperature of the first reforming gas is lower than that of the second reforming gas as an example.

[0054] Specifically, valve 243d is opened, and the second reformed gas flows into the gas supply pipe 232d. The flow rate of the second reformed gas is adjusted by MFC 241d and supplied into the processing chamber 201 via nozzle 249d, and exhausted from exhaust port 231a. At this time, the second reformed gas is supplied to the wafer 200 (second reformed gas supply step). Also at this time, valves 243f, 243g, 243h, and 243j are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a, 249b, 249c, and 249e, respectively.

[0055] (Purge step sp3) Subsequently, valve 243b is closed to stop the supply of the second reformed gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gases and other substances from within the processing chamber 201. At this time, valves 243f to 243j are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a to 249e. The N2 gas supplied from nozzles 249a to 249c acts as a purge gas, thereby purging the processing chamber 201.

[0056] (Step b2) After step b1 is completed, a second processing gas (second raw material gas) is supplied to the surface of the wafer 200 in the processing chamber 201. On the surface of the wafer 200, the adsorption of the second processing gas is inhibited in areas where the second reforming gas was adsorbed in step a1. In other words, in this step, a second processing gas containing the second element is supplied to the wafer 200, and the second element is preferentially adsorbed in areas of the wafer 200 that have not been reformed by the second reforming gas.

[0057] Specifically, valve 243c is opened, and the second processing gas is allowed to flow into the gas supply pipe 232c. The flow rate of the second processing gas is adjusted by MFC 241c, supplied into the processing chamber 201 via nozzle 249c, and exhausted from exhaust port 231a. At this time, the second processing gas is supplied to the wafer 200 (second processing gas supply step). Also at this time, valves 243g to 243i are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249b to 249d, respectively.

[0058] (Purge step sp4) After a film containing the second element is formed on the surface of the wafer 200, the valve 243c is closed to stop the supply of the second processing gas into the processing chamber 201. Then, any remaining gases in the processing chamber 201 are removed from the processing chamber 201 using the same processing procedure as in the purging step sp3.

[0059] [Step sc2: Performed a predetermined number of times] By performing the above steps b1 and b2 alternately, i.e., non-simultaneously without synchronization, a predetermined number of cycles (n2 times, where n2 is an integer of 1 or more), a film containing a second element of a desired thickness can be formed on the wafer 200 on top of a film containing a first element.

[0060] The processing conditions in the second film deposition step S2 are as follows: Second reformed gas supply flow rate: 10-5000 sccm Second reformed gas supply time: 1-300 minutes Second processing gas supply flow rate: 10-5000 sccm Second processing gas supply time: 1-300 minutes N2 gas supply flow rate (per gas supply pipe): 10-20000 sccm Processing temperature (second temperature): 450~550℃ Processing pressure: 30-400 Pa Examples are given.

[0061] (Substrate unloading process) The following steps are performed during the substrate removal process.

[0062] (After-purge and return to atmospheric pressure) After the deposition of the film containing the second element on the wafer 200 is complete, N2 gas is supplied as a purge gas into the processing chamber 201 from nozzles 249a to 249e and exhausted from exhaust port 231a. This purges the processing chamber 201, removing any remaining gases and reaction by-products (after-purging). Subsequently, the atmosphere inside the processing chamber 201 is replaced with an inert gas (inert gas replacement), and the pressure inside the processing chamber 201 is returned to atmospheric pressure (atmospheric pressure return).

[0063] (Boat unloading and wafer discharge) The seal cap 219 is lowered by the boat elevator 115, opening the lower end of the manifold 209. The processed wafer 200, supported by the boat 217, is then unloaded from the lower end of the manifold 209 to the outside of the reaction tube 203 (boat unloading). After boat unloading, the shutters 219s are moved, and the lower end opening of the manifold 209 is sealed by the shutters 219s via the O-ring 220c (shutter closing). After the processed wafer 200 has been unloaded from the reaction tube 203, it is removed from the boat 217 (wafer discharge).

[0064] One method for obtaining a film with good step coverage will be explained using Figures 6(a) to 6(c). In Figure 6, a trench (groove) 300, which is a recess, is formed on the surface of the substrate 200, and an example is shown in which a first treatment gas (first element) is adsorbed inside the trench 300. When the first reforming gas is supplied to the substrate surface as shown in Figure 6(a), the upper part of the trench (near the entrance of the recess) 301 will have more collisions with the gas than the lower part of the trench 300 (the deeper part of the recess) 302. From this, the first reforming gas can be preferentially adsorbed (or reacted) in the upper part of the trench 301. When the first treatment gas is supplied to the surface of the substrate 200 after the first reforming gas has been supplied, the adsorption of the first treatment gas (first element) is inhibited in the upper part of the trench 301 because the first reforming gas is adsorbed there, while it is adsorbed in the lower part of the trench 302 (Figure 6(b)). In other words, in the first film deposition step, a first processing gas containing the first element is supplied to the wafer 200, and the first element is preferentially adsorbed in the lower part of the trench 302, which has not been modified by the first modification gas. As a result, the upper part of the trench 301 has a small amount of the first element adsorbed, suppressing the increase in the film thickness, while the lower part of the trench 302 has a sufficient amount of the first element adsorbed, promoting an increase in film thickness (Figure 6(c)). Therefore, a film 303 containing the first element with better step coverage can be obtained.

[0065] In the example shown in the first substrate processing method, the decomposition temperature of the first reformed gas differs from that of the second reformed gas, with the first reformed gas having a lower decomposition temperature than the second reformed gas. This can be rephrased as the first reformed gas being more easily decomposed or more reactive than the second reformed gas. In such a case, the adsorption locations of the first reformed gas in the trench 300 are shown in Figure 7(a), and the adsorption locations of the second reformed gas in the trench 300 are shown in Figure 7(b). For the gas to adsorb to the lower part of the trench 302, it must enter the interior of the trench 300 from the upper part of the trench 301 and reach the lower part of the trench 302 without decomposing. In contrast, since the upper part of the trench 301 is more easily accessible to the gas than the lower part of the trench 302, the ease of gas adsorption in the upper part of the trench 301 due to the decomposition temperature does not change as much as in the lower part of the trench 302.

[0066] Therefore, it can be said that the first reformed gas is less effective at reforming the lower part of the trench 302 than the second reformed gas, or that the first reformed gas preferentially adsorbs (or reacts) with the upper part of the trench 301. Furthermore, it can be said that the second reformed gas reforms the lower part of the trench 302 more than the area reformed by the first reformed gas within the trench 300. Moreover, it can be said that the second reformed gas is capable of reforming the lower part of the trench 302 more than the area reformed by the first reformed gas within the trench 300.

[0067] For example, when performing the first and second film deposition steps as described above, the first reforming gas preferentially reforms the upper part 301 of the trench (Figure 8(a)). This inhibits the adsorption of the first element in the upper part 301 of the trench, while allowing the formation of a film 303a containing the first element in the lower part 302 of the trench (Figure 8(b)). Subsequently, the second reforming gas reforms a wider area on the lower part 302 side of the trench than the first reforming gas (Figure 8(c)). This suppresses the increase in film thickness in the upper part 301 of the trench, while forming a film 303b containing the second element with a more uniform film thickness than film 303a throughout the entire trench 300 (Figure 8(d)). As a result, uniform film deposition with good step coverage can be performed throughout the entire trench 300. Furthermore, as explained above, by using different temperatures in the first and second film deposition steps, the ease with which the first and second reformed gases decompose is altered. This allows for the modification of the regions within the trench 300 where the first and second reformed gases modify, thereby controlling the adsorption sites of the first and second elements. Additionally, by using different temperatures in the first and second film deposition steps, the ease with which the first or second processing gas decomposes can be controlled. For example, by setting the temperature in the second film deposition step higher than that in the first film deposition step, the second processing gas can be made more easily decomposed, increasing the thickness of the film containing the second element formed in the upper part of the trench 301.

[0068] Furthermore, the first processing gas (first raw material gas) may be configured to have a lower decomposition temperature than the second processing gas (second raw material gas). In this case, since the first processing gas decomposes more easily than the second processing gas, a film can be formed at a high rate even in the lower part of the trench 302, where the gas is difficult to reach. Also, since the second processing gas decomposes less easily than the first processing gas, the difference in decomposition between the upper part of the trench 301 and the lower part of the trench 302 becomes smaller, making it easier to form a film with a uniform thickness. Therefore, a film can be formed uniformly with good step coverage throughout the entire trench 300.

[0069] Furthermore, the upper trench 301 can be described as a location where gas can easily reach, and the lower trench 302 as a location where gas cannot easily reach, or simply as the lower trench 302. In this case, the first reformed gas is less likely to adsorb in locations where gas cannot easily reach, so it mainly reforms the locations where gas can easily reach. Therefore, in step a2, the first treatment gas can adsorb the first element in locations where gas cannot easily reach, while inhibiting the adsorption of the first element in locations where gas can easily reach. Subsequently, by using a second reformed gas that is more likely to adsorb even in locations where gas cannot easily reach, a film containing the second element can be formed in step b2 with good stepped coverage.

[0070] In the first substrate processing method, an example was described in which a film containing a second element is formed on a film containing a first element by performing a second film formation step after a first film formation step. The method of this disclosure is not limited to this, and can be suitably used, for example, when a film is formed by laminating a film containing a first element and a film containing a second element by performing a cycle including the first film formation step and the second film formation step a predetermined number of times.

[0071] (2-2) Second substrate processing method Figure 4 shows a second substrate processing method according to an embodiment. Figure 5 shows the configuration of the gas supply piping system used in the second substrate processing method.

[0072] The second substrate processing method shown in Figure 4 consists of a first film deposition step, a second film deposition step, and a third film deposition step. The third film deposition step in Figure 4 corresponds to the second film deposition step in Figure 3. The first film deposition step in Figure 3 can also be seen as being divided into a first film deposition step and a second film deposition step in Figure 4.

[0073] In Figure 4, the first and second film deposition steps are performed at the same first processing temperature, while the third film deposition step is performed at a second processing temperature that is higher than the first processing temperature.

[0074] As shown in Figure 5, the gas supply piping system has the following additions compared to the gas supply piping system in Figure 1: gas supply pipe 232m, MFC 241m, valve 243m, gas supply pipe 232n, MFC 241n, valve 243n, nozzle 249f, and gas supply hole 250f.

[0075] The second substrate processing method will be explained below using Figure 4, but the parts that are the same as those in Figure 3 will be omitted from the explanation.

[0076] (First film deposition step: S1) In the first film deposition step S1, the following steps (processes) are performed.

[0077] (Step a1) In this step, a first reforming gas is supplied to the wafer 200 in the processing chamber 201 to reform at least a portion of the wafer 200.

[0078] Specifically, valve 243b is opened, and the first reformed gas flows into the gas supply pipe 232b. The flow rate of the first reformed gas is adjusted by MFC 241b, supplied into the processing chamber 201 via nozzle 249b, and exhausted from exhaust port 231a. At this time, the first reformed gas is supplied to the wafer 200 (first reformed gas supply step). Also at this time, valves 243f, 243h, 243i, 243j, and 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a, 249c, 249d, 249e, and 249f, respectively.

[0079] (Purge step sp1) Subsequently, valve 243b is closed to stop the supply of the first reformed gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gases and other substances from within the processing chamber 201. At this time, valves 243f to 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a to 249f. The N2 gas supplied from nozzles 249a to 249f acts as a purge gas, thereby purging the processing chamber 201.

[0080] (Step a2) After step a1 is completed, a first processing gas is supplied to the surface of the wafer 200 in the processing chamber 201. On the surface of the wafer 200, the adsorption of the first processing gas is inhibited in areas where the first modifying gas was adsorbed in step a1. In other words, in this step, a first processing gas containing the first element is supplied to the wafer 200, and the first element is preferentially adsorbed in areas of the wafer 200 that have not been modified by the first modifying gas.

[0081] Specifically, valve 243a is opened, and the first processing gas flows into the gas supply pipe 232a. The flow rate of the first processing gas is adjusted by MFC 241a, supplied into the processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, the first processing gas is supplied to the wafer 200 (first processing gas supply step). Also at this time, valves 243g to 243i and 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249b to 249d and 249f, respectively.

[0082] (Purge step sp2) After a nucleus is formed in the lower part 302 of the recess 300, the valve 243a is closed to stop the supply of the first processing gas into the processing chamber 201. Then, any remaining gas and other substances in the processing chamber 201 are removed from the processing chamber 201 using the same processing procedure as in the purging step sp1.

[0083] [Step sc1: Performed a predetermined number of times] A film containing the first element can be formed by performing the above steps a1 and a2 alternately, i.e., non-simultaneously, a predetermined number of cycles (n1 times, where n1 is an integer of 1 or more).

[0084] In the first film deposition step, the thickness of the film containing the first element formed on the wafer 200 can be controlled by controlling at least one of the following processing temperatures and processing times (first reforming gas supply time, first processing gas supply time). Furthermore, in the first film deposition step, the thickness of the film containing the first element formed on the wafer 200 can also be controlled by controlling the number of cycles performed as described above.

[0085] The processing conditions in step a1 are: First reformed gas supply flow rate: 10-1000 sccm First reformed gas supply time: 0.5-10 minutes N2 gas supply flow rate (per gas supply pipe): 10-10000 sccm Processing temperature (first temperature): 350~420℃ Processing pressure: 100~1000Pa Examples are given.

[0086] The processing conditions in step a2 are: First treatment gas supply flow rate: 10-1000 sccm First processing gas supply time: 0.5-10 minutes This is an example. Other processing conditions are the same as the processing conditions in step a1.

[0087] (Second film deposition step: S2) After the first film deposition step S1, the second film deposition step S2 is performed. In the second film deposition step S2, the following steps (processes) are performed.

[0088] (Step b1) In this step, a second reforming gas is supplied to the wafer 200 in the processing chamber 201 to reform at least a portion of the previous wafer 200.

[0089] Specifically, valve 243d is opened, and the second reformed gas flows into the gas supply pipe 232d. The flow rate of the second reformed gas is adjusted by MFC 241d and supplied into the processing chamber 201 via nozzle 249d, and exhausted from exhaust port 231a. At this time, the second reformed gas is supplied to the wafer 200 (second reformed gas supply step). Also at this time, valves 243f, 243g, 243h, 243j, and 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a, 249b, 249c, 249e, and 249f, respectively.

[0090] (Purge step sp3) Subsequently, valve 243d is closed to stop the supply of the second reforming gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gases and other substances from within the processing chamber 201. At this time, valves 243f to 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a to 249f. The N2 gas supplied from nozzles 249a to 249f acts as a purge gas, thereby purging the processing chamber 201.

[0091] (Step b2) After step b1 is completed, a second processing gas (second raw material gas) is supplied to the surface of the wafer 200 in the processing chamber 201. On the surface of the wafer 200, the adsorption of the second processing gas is inhibited in areas where the second modifying gas was adsorbed in step b1. In other words, in this step, a second processing gas containing the second element is supplied to the wafer 200, and the second element is preferentially adsorbed in areas of the wafer 200 that have not been modified by the second modifying gas.

[0092] Specifically, valve 243a is opened, and the second processing gas flows into the gas supply pipe 232a. The flow rate of the second processing gas is adjusted by MFC 241a, supplied into the processing chamber 201 via nozzle 249a, and exhausted from exhaust port 231a. At this time, the first processing gas is supplied to the wafer 200 (second processing gas supply step). Also at this time, valves 243g to 243i and 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249b to 249d and 249f, respectively.

[0093] (Purge step sp4) After a film containing the second element is formed on the surface of the wafer 200, the valve 243a is closed to stop the supply of the second processing gas into the processing chamber 201. Then, any remaining gases and other substances in the processing chamber 201 are removed from the processing chamber 201 using the same processing procedure as in the purging step sp3.

[0094] [Step sc2: Performed a predetermined number of times] By performing the above steps b1 and b2 alternately, i.e., non-simultaneously without synchronization, a predetermined number of cycles (n2 times, where n2 is an integer greater than or equal to 1), a film containing the second element can be formed on a film containing the first element.

[0095] In the second film deposition step, the thickness of the film containing the second element formed on the wafer 200 can be controlled by controlling at least one of the following processing temperatures and processing times (second reforming gas supply time, second processing gas supply time). Furthermore, in the second film deposition step, the thickness of the film containing the second element formed on the wafer 200 can also be controlled by controlling the number of cycles performed as described above.

[0096] The processing conditions in step b1 are: Second reformed gas supply flow rate: 10-1000 sccm Second reformed gas supply time: 0.5-10 minutes N2 gas supply flow rate (per gas supply pipe): 10-10000 sccm Processing temperature (first temperature): 350~420℃ Processing pressure: 100~1000Pa Examples are given.

[0097] The processing conditions in step b2 are: Second processing gas supply flow rate: 10-1000 sccm Second processing gas supply time: 0.5-10 minutes This is an example. Other processing conditions are the same as the processing conditions in step b1.

[0098] (Temperature rise step st1: Temperature adjustment step) After a film containing the second element is formed on the wafer 200, the output of the heater 207 is adjusted to change the temperature inside the processing chamber 201, i.e., the temperature of the wafer 200, to a second temperature higher than the first temperature (350-420°C) described above. When performing this step, valves 243f-243j and 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a-249f and exhausted from exhaust port 231a to purge the processing chamber 201. After the temperature of the wafer 200 reaches the second temperature and stabilizes, the steps described later are started. Here, the second temperature is, for example, in the temperature range of 450-550°C.

[0099] (Third film deposition step: S3) Next, the third film deposition step S3 is performed. In the third film deposition step S3, the following steps (processes) are executed.

[0100] (Step c1) In this step, at least a portion of the substrate is modified by supplying a first modifying gas and a third modifying gas having a different decomposition temperature from the second modifying gas to the surface of the wafer 200 in the processing chamber 201, i.e., the film containing the second element formed on the wafer 200.

[0101] Specifically, valve 243c is opened, and the third reformed gas flows into the gas supply pipe 232c. The flow rate of the third reformed gas is adjusted by MFC 241c and supplied into the processing chamber 201 via nozzle 249c, and exhausted from exhaust port 231a. At this time, the third reformed gas is supplied to the wafer 200 (second reformed gas supply step). Also at this time, valves 243f, 243g, 243i, 243j, and 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a, 249b, 249d, 249e, and 249f, respectively.

[0102] (Purge step sp5) Subsequently, valve 243c is closed to stop the supply of STS gas into the processing chamber 201. Then, the processing chamber 201 is evacuated to remove any remaining gases and other substances from within the processing chamber 201. At this time, valves 243f~243j and 243n are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249a~249f. The N2 gas supplied from nozzles 249a~249f acts as a purge gas, thereby purging the processing chamber 201.

[0103] (Step c2) After step c1 is completed, a third processing gas (third raw material gas) is supplied to the surface of the wafer 200 in the processing chamber 201. Here, the adsorption of the third processing gas is inhibited in areas of the wafer 200 surface where the third modifying gas was adsorbed in step c1. In other words, in this step, a third processing gas containing the third element is supplied to the wafer 200, and the third element is preferentially adsorbed in areas of the wafer 200 that have not been modified by the third modifying gas.

[0104] Specifically, valve 243m is opened, and the third processing gas is introduced into the gas supply pipe 232m. The flow rate of the third processing gas is adjusted by MFC 241m, supplied into the processing chamber 201 via nozzle 249f, and exhausted from exhaust port 231a. At this time, the third processing gas is supplied to the wafer 200 (third processing gas supply step). Also at this time, valves 243g to 243i are opened, and N2 gas is supplied into the processing chamber 201 via nozzles 249b to 249d, respectively.

[0105] (Purge step sp6) After a film containing the third element (third film, third layer) is formed on the surface of the wafer 200, the valve 243m is closed to stop the supply of the third processing gas into the processing chamber 201. Then, the remaining gas and other substances in the processing chamber 201 are removed from the processing chamber 201 using the same processing procedure as in the purge step sp5.

[0106] [Step sc3: Performed a predetermined number of times] By performing the above steps c1 and c2 alternately, i.e., non-simultaneously, a predetermined number of cycles (n3 times, where n3 is an integer greater than or equal to 1), a film containing a third element of a desired thickness can be formed on a film containing a second element.

[0107] The processing conditions in the third film deposition step S3 are as follows: Third reformed gas supply flow rate: 10-5000 sccm Third reformed gas supply time: 1-300 minutes Third-stage processing gas supply flow rate: 10-5000 sccm Third-stage processing gas supply time: 1-300 minutes N2 gas supply flow rate (per gas supply pipe): 10-20000 sccm Processing temperature (second temperature): 450~550℃ Processing pressure: 30-400 Pa Examples are given.

[0108] The second substrate processing method provides the same effects as the first substrate processing method, in addition to the following effects.

[0109] The first and second film deposition steps are performed at the same temperature. Furthermore, the decomposition temperature of the first reformed gas is lower than that of the second reformed gas. As a result, without changing the temperature inside the processing chamber 201 between the first and second film deposition steps, it is possible to make the areas where the first and second reformed gases are reformed, i.e., the regions where the first element is preferentially adsorbed and the regions where the second element is preferentially adsorbed, different.

[0110] In the third film deposition step, a film containing the third element is formed at a higher temperature than in the first and second film deposition steps, on top of the film that has been formed in the first and second film deposition steps with good step coverage. Therefore, in the third film deposition step, a film containing the third element can be formed with good step coverage at a higher deposition rate than in the first and second film deposition steps.

[0111] In the first and second film deposition steps, the decomposition temperature of the first processing gas may be the same as that of the second processing gas. Alternatively, the first and second processing gases may be the same gas. From the above, in film deposition using processing gases with the same decomposition temperature, it becomes possible to control the location where the first element (second element) is mainly adsorbed without changing the temperature conditions. Using this, the uniformity of the film thickness from the deep part 302 to the entrance area 301 of the recess 300 in the film formed in the first and second film deposition steps can be improved.

[0112] In the second substrate processing method, an example was described in which a Si film is formed by performing a second film deposition step after a first film deposition step, and then a third film deposition step. The method of this disclosure is not limited to this, and for example, the third film deposition step may be performed after a predetermined number of cycles including the first film deposition step and the second film deposition step.

[0113] This disclosure is not limited to the embodiments described above and is subject to various modifications.

[0114] In the embodiments described above, the first reformed gas, second reformed gas, and third reformed gas can be, for example, gases containing halogen elements, such as a first halogen element, a second halogen element, and a third halogen element. Halogen elements include chlorine (Cl), fluorine (F), bromine (Br), iodine (I), etc. Alternatively, the first reformed gas, second reformed gas, and third reformed gas may be gases containing a first element, a second element, and a third element, and a first halogen element, a second halogen element, and a third halogen element, respectively. Here, halogen elements have the effect of inhibiting gas adsorption and are less likely to remain as impurities in the film, thus less likely to degrade the electrical properties of the film.

[0115] As a halogen-containing gas, for example, a halosilane gas containing Si and a halogen element can be used. As a halosilane gas, for example, a chlorosilane gas containing Si and Cl can be used, and includes, for example, dichlorosilane (SiH2Cl2, abbreviation: DCS) gas, trichlorosilane (SiHCl3) gas, tetrachlorosilane (SiCl4, abbreviation: TCS), pentachlorodisilane (Si2H1Cl5, abbreviation: PCDS), hexachlorodisilane (Si2Cl6, abbreviation: HCDS) gas, etc. Also, as a halogen-containing gas, for example, a hydrogen halide gas can be used, and includes, for example, hydrogen fluoride (HF) gas, hydrogen chloride (HCl) gas, hydrogen bromide (HBr) gas, hydrogen iodide (HI) gas, etc. That is, from among these gases, the first reformed gas, second reformed gas, and third reformed gas may be appropriately selected and used so that the relationship between the decomposition temperatures is as described in the above embodiment.

[0116] In the above-described embodiment, when the first, second, and third elements are Si, Si-containing gases can be used as the first, second, and third processing gases. For example, a silane gas with Si as the main element can be used as the Si-containing gas. Examples of silane gases include monosilane (SiH4, abbreviated as MS) gas, disilane (Si2H6, abbreviated as DS) gas, and trisilane (Si3H8, abbreviated as TS) gas. Halosilane gas can also be used as the silane gas.

[0117] In the first substrate processing method, a film containing the second element may be formed using a film containing the first element as a seed layer (seed film). This allows for the formation of high-density crystal nuclei in the film containing the first element, which can then be used as growth nuclei to grow a film containing the second element in an amorphous, epitaxial, or polystate. Similarly, in the second substrate processing method, a film containing the second element may be formed using a film containing the first element as a seed layer. Furthermore, a film containing the third element may be formed using a film containing the second element as a seed layer. Furthermore, a film containing the third element may be formed using a film composed of the first and second elements as a seed layer.

[0118] In the embodiments described above, the first element may be, for example, Si or germanium (Ge), which are Group 14 elements, or aluminum (Al), gallium (Ga), or indium (In), which are Group 13 elements. Alternatively, a transition metal element may be used as the first element. Examples of transition metal elements that may be used as the first element include titanium (Ti), zirconium (Zr), and Hf (hafnium), which are Group 4 elements; niobium (Nb) and tantalum (Ta), which are Group 5 elements; molybdenum (Mo) and tungsten (W), which are Group 6 elements; manganese (Mn), which is Group 7 element; ruthenium (Ru), which is Group 8 element; cobalt (Co), which is Group 9 element; and nickel (Ni), which is Group 10 element. These elements may also be used as the second and third elements, similar to the first element.

[0119] In the first substrate processing method, the first element and the second element may be different elements. In the second substrate processing method, one or more of the first element, the second element, and the third element may be different elements.

[0120] Higher-order halosilane gases have lower decomposition temperatures than lower-order halosilane gases. For example, among halosilane gases, HCDS gas has a lower decomposition temperature than TCS gas. That is, if the first and second reformed gases are halosilane gases, the decomposition temperature of the first reformed gas can be made lower than that of the second reformed gas by using a higher-order halosilane gas for the first reformed gas. The same relationship holds even if the first and second reformed gases are gases whose main element is an element other than Si. That is, if the first and second reformed gases are gases whose main element is the same element, the decomposition temperature of the first reformed gas can be made lower than that of the second reformed gas by using a higher-order gas for the first reformed gas.

[0121] Furthermore, a similar relationship holds true for silane gases. For example, DS gas has a lower decomposition temperature than MS gas, and TS gas has a lower decomposition temperature than DS gas. That is, if the first and second process gases are silane gases, the decomposition temperature of the first process gas can be made lower than that of the second process gas by making the first process gas a higher-order silane gas than the second process gas. The same relationship also holds true when the first and second process gases are gases whose main element is an element other than Si. That is, if the first and second process gases are gases whose main element is the same element, the decomposition temperature of the first process gas can be made lower than that of the second process gas by making the first process gas a higher-order gas than the second process gas.

[0122] In the case of two halosilane gases of the same order, the lower the molecular symmetry, the lower the decomposition temperature may be. For example, PCDS gas has a lower decomposition temperature than HCDS gas, and TCS gas has a lower decomposition temperature than DCS gas. That is, if the first and second reformed gases are halosilane gases of the same order, the decomposition temperature of the first reformed gas can be made lower than that of the second reformed gas by using a halosilane gas with lower molecular symmetry for the first reformed gas. The same relationship may also hold if the first and second reformed gases are gases of the same order with elements other than Si as the main element. That is, if the first and second reformed gases are gases of the same order with the same main element, the decomposition temperature of the first reformed gas can be made lower than that of the second reformed gas by using a gas with lower molecular symmetry for the first reformed gas.

[0123] Furthermore, a similar relationship may hold true for the first process gas (first raw material gas) and the second process gas (second raw material gas). For example, DCS gas has a lower decomposition temperature than MS gas. That is, if the first and second process gases are silane gases of the same order, it may be possible to lower the decomposition temperature of the first process gas to that of the second process gas by making the molecular symmetry of the first process gas lower than that of the second process gas. Also, a similar relationship may hold true if the first and second process gases are gases whose main element is an element other than Si. That is, if the first and second process gases are gases of the same order with the same main element, it may be possible to lower the decomposition temperature of the first process gas to that of the second process gas by making the molecular symmetry of the first process gas lower than that of the second process gas.

[0124] Furthermore, the relationship between the molecular structure and decomposition temperature of the first and second reformed gases described above holds true even when the first reformed gas is replaced with the third reformed gas, and even when the second reformed gas is replaced with the third reformed gas. Similarly, the relationship between the molecular structure and decomposition temperature of the first processed gas (first raw material gas) and the second processed gas (first raw material gas) described above holds true even when the first processed gas (first raw material gas) is replaced with the third processed gas (third raw material gas), and even when the second processed gas (second raw material gas) is replaced with the third processed gas (third raw material gas).

[0125] In the above-described embodiment (first substrate processing method or second substrate processing method), the first film formation step was described in an example in which a predetermined number of cycles in which steps a1 and a2 are performed alternately were described. The method of this disclosure is not limited thereto. For example, in the above-described embodiment, the supply conditions of the first reforming gas in step a1 and the first processing gas (first raw material gas) in step a2 can be changed in cycles after a certain number of cycles, or a cycle in which step a1 is not performed can be provided. Similarly, in the above-described embodiment, for example, the supply conditions of the second reforming gas in step b1 and the second processing gas (second raw material gas) in step b2 can be changed in cycles after a certain number of cycles, or a cycle in which step b1 is not performed can be provided. Similarly, in the above-described embodiment, in the third film formation step, for example, the supply conditions of the third reforming gas in step c1 and the third processing gas (third raw material gas) in step c2 can be changed in cycles after a certain number of cycles, or a cycle in which step c1 is not performed can be provided.

[0126] In the embodiments described above, an example using N2 gas as the inert gas was explained, but the invention is not limited to this, and noble gases such as argon (Ar) gas, helium (He) gas, neon (Ne) gas, and xenon (Xe) gas may also be used.

[0127] In the embodiments described above, an example was given in which a first raw material gas is supplied to the processing chamber 201 (wafer 200) as a first processing gas in step (a2) of the first film deposition step, but the technology of this disclosure is not limited thereto. For example, silane gas may be supplied to the processing chamber 201 as the first processing gas, and oxygen-containing gas or nitrogen-containing gas may be supplied to the processing chamber 201 as the first reaction gas. Specifically, after supplying silane gas to the processing chamber 201, the valve 243e may be opened and oxygen-containing gas or nitrogen-containing gas may be supplied to the processing chamber 201 as the first reaction gas into the gas supply pipe 232e (first reaction gas supply step). In that case, a silicon oxide (SiO2) film or a silicon nitride (SiN) film will be formed in the first film deposition step. At this time, the first raw material gas and the first reaction gas may be supplied to the processing chamber 201 sequentially a predetermined number of times.

[0128] Similarly, the second raw material gas and the second reaction gas may be supplied to the processing chamber 201 as the second processing gas, or the second raw material gas and the second reaction gas may be supplied to the processing chamber 201 sequentially a predetermined number of times as the second processing gas. Also, similarly, the third raw material gas and the third reaction gas may be supplied to the processing chamber 201 as the third processing gas, or the third raw material gas and the third reaction gas may be supplied to the processing chamber 201 sequentially a predetermined number of times as the third processing gas. For example, an oxygen-containing gas or a nitrogen-containing gas may be used as the second or third processing gas.

[0129] As oxygen-containing gases, for example, oxygen (O2) gas, nitrous oxide (N2O) gas, nitric oxide (NO) gas, nitrogen dioxide (NO2) gas, ozone (O3) gas, water vapor (H2O) gas, carbon monoxide (CO) gas, carbon dioxide (CO2) gas, etc. can be used in combinations such as O2 gas + hydrogen (H2) gas, O3 gas + H2 gas, H2O gas + H2 gas, etc. In this specification, the joint mention of two gases such as "O3 gas + H2 gas" refers to a mixed gas of O3 gas and H2 gas. As nitrogen-containing gases, for example, nitrogen-containing gases containing NH bonds (gases containing N and H), such as ammonia (NH3) gas, hydrazine (N2H4) gas, diazene (N2H2) gas, N3H8 gas, etc., or N2 gas can be used.

[0130] The above-described embodiments illustrate an example of forming a film using a batch-type substrate processing apparatus that processes multiple substrates at once. This disclosure is not limited to the above embodiments and can be suitably applied, for example, to forming a film using a single-wafer substrate processing apparatus that processes one or several substrates at once. Furthermore, the above-described embodiments illustrate an example 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 to forming a film using a substrate processing apparatus having a cold-wall type processing furnace.

[0131] 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.

[0132] 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. [Explanation of Symbols]

[0133] 10: Substrate processing equipment 248: Integrated supply system 121: Control Unit (Controller)

Claims

1. (a1) A step of supplying a first reforming gas to the substrate to reform at least a portion of the substrate, (a2) A step of supplying a first processing gas containing a first element to the substrate to preferentially adsorb the first element to regions that have not been modified by the first modification gas, A first film formation step which includes forming a first film containing the aforementioned first element, (b1) A step of supplying a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate, thereby reforming at least a portion of the substrate. (b2) A step of supplying a second processing gas containing a second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, A second film formation step comprising forming a second film containing the second element using the first film as a seed film, A substrate processing method having the following characteristics.

2. (a1) A step of supplying a first reforming gas to a substrate to reform at least a portion of the substrate, (a2) A step of supplying a first processing gas containing a first element to the substrate to preferentially adsorb the first element to regions that have not been modified by the first modification gas, A first film formation step which includes forming a first film containing the aforementioned first element, (b1) A step of supplying a second reforming gas having a higher decomposition temperature than the first reforming gas to the substrate, thereby reforming at least a portion of the substrate, (b2) A step of supplying a second processing gas containing a second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, The process includes a second film formation step in which a second film containing the second element is formed after the first film formation step, A substrate processing method having the following characteristics.

3. (a1) A step of supplying a first reforming gas to a substrate to reform at least a portion of the substrate, (a2) A step of supplying a first processing gas containing a first element to the substrate to preferentially adsorb the first element to regions that have not been modified by the first modification gas, A first film formation step which includes forming a first film containing the aforementioned first element, (b1) A step of supplying a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate, thereby reforming at least a portion of the substrate. (b2) A step of supplying a second processing gas containing a second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, The process includes a second film formation step in which a second film containing the second element is formed after the first film formation step, It has, The first reformed gas contains the first element, and the second reformed gas contains the second element. Substrate processing method.

4. (a2) The substrate processing method according to any one of claims 1 to 3, wherein a first raw material gas containing the first element and a first reaction gas are supplied as the first processing gas.

5. (b2) The substrate processing method according to any one of claims 1 to 3, wherein a second raw material gas containing the second element as the second processing gas and a second reaction gas are supplied.

6. The substrate processing method according to any one of claims 1 to 3, wherein the decomposition temperature of the first processing gas is the same as that of the second processing gas.

7. The substrate processing method according to any one of claims 1 to 3, wherein the first film formation step is performed at the same temperature as the second film formation step.

8. After performing the first film formation step and the second film formation step a predetermined number of times, (c) The process further comprises supplying the substrate with a third processing gas containing a third element and having a higher decomposition temperature than the first processing gas and the second processing gas, thereby adsorbing the third element onto the substrate. (c) The substrate processing method according to any one of claims 1 to 3, wherein (c) is performed at a temperature higher than the first film formation step and the second film formation step.

9. The substrate processing method according to claim 1 or 3, wherein the first reformed gas has a lower decomposition temperature than the second reformed gas.

10. The substrate processing method according to claim 9, wherein the first film formation step is performed at a lower temperature than the second film formation step.

11. The substrate processing method according to any one of claims 1 to 3, wherein the first processing gas has a lower decomposition temperature than the second processing gas.

12. The substrate has a recess, The first reformed gas has a lower decomposition temperature than the second reformed gas. The substrate processing method according to any one of claims 1 to 3, wherein the second reforming gas reforms the deeper part of the recess than the area reformed by the first reforming gas within the recess.

13. The substrate processing method according to claim 12, wherein the first film deposition step is performed at a lower temperature than the second film deposition step.

14. The substrate processing method according to claim 12, wherein the first processing gas has a lower decomposition temperature than the second processing gas.

15. The substrate processing method according to any one of claims 1 to 3, wherein the first reforming gas contains a first halogen element and the second reforming gas contains a second halogen element.

16. The substrate processing method according to claim 15, wherein the first halogen element and the second halogen element are chlorine.

17. The substrate processing method according to claim 1 or 2, wherein the first reformed gas contains the first element and the second reformed gas contains the second element.

18. The first reformed gas and the second reformed gas are gases whose main element is the same element. The first reformed gas is a higher-order gas than the second reformed gas. A substrate processing method according to any one of claims 1 to 3.

19. The first reformed gas and the second reformed gas are gases of the same order, with the same element as the main element. The first reformed gas is a gas with lower molecular symmetry than the second reformed gas. A substrate processing method according to any one of claims 1 to 3.

20. The substrate processing method according to any one of claims 1 to 3, wherein the first film formation step is performed at a temperature lower than that of the second film formation step.

21. The substrate has a recess, The first reformed gas and the second reformed gas preferentially reform the region on the inlet side of the recess rather than the deeper side of the recess. A substrate processing method according to any one of claims 1 to 3.

22. (a1) A step of supplying a first reforming gas to the substrate to reform at least a portion of the substrate, (a2) A step of supplying a first processing gas containing a first element to the substrate to preferentially adsorb the first element to regions that have not been modified by the first modification gas, A first film formation step which includes forming a first film containing the aforementioned first element, (b1) A step of supplying a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate, thereby reforming at least a portion of the substrate. (b2) A step of supplying a second processing gas containing a second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, A second film formation step comprising forming a second film containing the second element using the first film as a seed film, A method for manufacturing a semiconductor device having [a certain feature].

23. A first reformed gas supply system that supplies a first reformed gas to the substrate, A first processing gas supply system that supplies a first processing gas containing a first element to the substrate, A second reformed gas supply system supplies a second reformed gas having a different decomposition temperature from the first reformed gas to the substrate, A second processing gas supply system that supplies a second processing gas containing a second element to the substrate, (a1) A process of supplying the first reforming gas to the substrate to reform at least a portion of the substrate, (a2) A process in which the first processing gas is supplied to the substrate to preferentially adsorb the first element in the region that has not been modified by the first modifying gas, A first film formation process that includes and forms a first film containing the first element, (b1) A process to modify at least a portion of the substrate by supplying a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate, (b2) A process in which the second processing gas is supplied to the substrate to preferentially adsorb the second element in the region that has not been modified by the second modifying gas, A second film formation process comprising: a first film being used as a seed film to form a second film containing the second element, A substrate processing apparatus having a control unit configured to control the first reformed gas supply system, the first processing gas supply system, the second reformed gas supply system, and the second processing gas supply system so as to perform the following:

24. (a1) A procedure to supply a first reforming gas to a substrate to reform at least a portion of the surface of the substrate, (a2) A procedure to supply a first processing gas containing a first element to the substrate, thereby preferentially adsorbing the first element to regions that have not been modified by the first modification gas, A first film formation procedure comprising, and forming a first film containing the first element, (b1) A procedure to supply a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate, thereby reforming at least a portion of the surface of the substrate, (b2) A procedure to supply a second processing gas containing the second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, A second film formation procedure comprising: a first film being used as a seed film to form a second film containing the second element, A program that causes a circuit board processing device to execute a procedure having the following characteristics via a computer.

25. (a1) A step of supplying a first reforming gas to a substrate to reform at least a portion of the substrate, (a2) A step of supplying a first processing gas containing a first element to the substrate to preferentially adsorb the first element to regions that have not been modified by the first modification gas, A first film formation step which includes forming a first film containing the aforementioned first element, (b1) A step of supplying a second reforming gas having a higher decomposition temperature than the first reforming gas to the substrate, thereby reforming at least a portion of the substrate, (b2) A step of supplying a second processing gas containing a second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, The process includes a second film formation step in which a second film containing the second element is formed after the first film formation step, A method for manufacturing a semiconductor device having [a certain feature].

26. A first reformed gas supply system that supplies a first reformed gas to a substrate, A first processing gas supply system that supplies a first processing gas containing a first element to the substrate, A second reformed gas supply system supplies a second reformed gas having a higher decomposition temperature than the first reformed gas to the substrate, A second processing gas supply system that supplies a second processing gas containing a second element to the substrate, (a1) A process of supplying the first reforming gas to the substrate to reform at least a portion of the substrate, (a2) A process in which the first processing gas is supplied to the substrate to preferentially adsorb the first element in the region that has not been modified by the first modifying gas, A first film formation process that includes and forms a first film containing the first element, (b1) A process of supplying the second reforming gas to the substrate to reform at least a portion of the substrate, (b2) A process in which the second processing gas is supplied to the substrate to preferentially adsorb the second element in the region that has not been modified by the second modifying gas, A second film formation process, which includes the first film formation process, in which a second film containing the second element is formed after the first film formation process, A control unit configured to control the first reformed gas supply system, the first processed gas supply system, the second reformed gas supply system, and the second processed gas supply system so as to perform the following: A substrate processing apparatus having

27. ​​(a1) A procedure for supplying a first reforming gas to a substrate to reform at least a portion of the substrate, (a2) A procedure to supply a first processing gas containing a first element to the substrate, thereby preferentially adsorbing the first element to regions that have not been modified by the first modification gas, A first film formation procedure comprising, and forming a first film containing the first element, (b1) A procedure to supply a second reforming gas having a higher decomposition temperature than the first reforming gas to the substrate, thereby reforming at least a portion of the substrate, (b2) A procedure to supply a second processing gas containing the second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, A second film formation step, which includes forming a second film containing the second element after the first film formation step, A program that causes a circuit board processing device to execute a procedure having the following characteristics via a computer.

28. (a1) A step of supplying a first reforming gas to a substrate to reform at least a portion of the substrate, (a2) A step of supplying a first processing gas containing a first element to the substrate to preferentially adsorb the first element to regions that have not been modified by the first modification gas, A first film formation step which includes forming a first film containing the aforementioned first element, (b1) A step of supplying a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate, thereby reforming at least a portion of the substrate. (b2) A step of supplying a second processing gas containing a second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, The process includes a second film formation step in which a second film containing the second element is formed after the first film formation step, It has, The first reformed gas contains the first element, and the second reformed gas contains the second element. A method for manufacturing a semiconductor device having [a certain feature].

29. A first reformed gas supply system for supplying a first reformed gas to a substrate, A first processing gas supply system that supplies a first processing gas containing a first element to the substrate, A second reformed gas supply system supplies a second reformed gas having a different decomposition temperature from the first reformed gas to the substrate, A second processing gas supply system that supplies a second processing gas containing a second element to the substrate, (a1) A process of supplying the first reforming gas to the substrate to reform at least a portion of the substrate, (a2) A process in which the first processing gas is supplied to the substrate to preferentially adsorb the first element in the region that has not been modified by the first modifying gas, A first film formation process that includes and forms a first film containing the first element, (b1) A process of supplying the second reforming gas to the substrate to reform at least a portion of the substrate, (b2) A process in which the second processing gas is supplied to the substrate to preferentially adsorb the second element in the region that has not been modified by the second modifying gas, A second film formation process, which includes the first film formation process, in which a second film containing the second element is formed after the first film formation process, A control unit configured to control the first reformed gas supply system, the first processed gas supply system, the second reformed gas supply system, and the second processed gas supply system so as to perform the following: It has, The first reformed gas contains the first element, and the second reformed gas contains the second element. Circuit board processing equipment.

30. (a1) A procedure for supplying a first reforming gas to a substrate to reform at least a portion of the substrate, (a2) A procedure to supply a first processing gas containing a first element to the substrate, thereby preferentially adsorbing the first element to regions that have not been modified by the first modification gas, A first film formation procedure comprising, and forming a first film containing the first element, (b1) A procedure to modify at least a portion of the substrate by supplying a second reforming gas having a different decomposition temperature from the first reforming gas to the substrate, (b2) A procedure to supply a second processing gas containing the second element to the substrate so that the second element is preferentially adsorbed in areas that have not been modified by the second modification gas, A second film formation step, which includes forming a second film containing the second element after the first film formation step, It has, The procedure involves the first reformed gas containing the first element and the second reformed gas containing the second element, A program that a computer instructs a circuit board processing unit to execute.

Images