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

Abstract

The invention relates to a substrate processing method, a method of manufacturing a semiconductor device, a program product, and a substrate processing apparatus. The present invention addresses the problem of precisely forming a film in a recess provided in the surface of a substrate. [Solution] The method comprises: (a) a step in which a film-forming agent is supplied to a substrate having, on the surface thereof, a recess having a bottom surface comprising a first base and side surfaces comprising a second base, and a first film is formed on the first base so as to be thicker than the thickness of the first film formed on the second base; and (b) a step of supplying an etchant to the substrate, and removing the first film formed on the second base in a state in which at least a portion of the first film formed on the first base remains.

Description

TECHNICAL FIELD

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

[0002] As one of the processes of manufacturing a semiconductor device, a process of forming a film on a surface of a substrate is sometimes performed (see, for example, Patent Literature 1).

[0003] PRIOR ART DOCUMENT

[0004] PATENT LITERATURE

[0005] Patent Literature 1: Japanese Patent Application Publication No. 2021-136349 SUMMARY

[0006] PROBLEMS TO BE SOLVED BY THE INVENTION

[0007] The present disclosure provides a technology capable of precisely forming a film in a recess provided on a surface of a substrate.

[0008] MEANS FOR SOLVING THE PROBLEMS

[0009] According to one embodiment of the present disclosure, there is provided a technology having:

[0010] (a) a process of supplying a film forming agent to a substrate having a recess with a bottom surface composed of a first base and a side surface composed of a second base on a surface, and forming a first film on the first base in a manner thicker than a thickness of a second film formed on the second base; and

[0011] (b) a process of supplying an etching agent to the substrate, and removing the first film formed on the second base in a state where at least a part of the first film formed on the first base remains.

[0012] EFFECT OF THE INVENTION

[0013] According to the present disclosure, a film can be precisely formed in a recess provided on a surface of a substrate. BRIEF DESCRIPTION OF DRAWINGS

[0014] [ Figure 1 ] Figure 1 A schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitable for use in one embodiment of the present disclosure is a diagram showing a part of a processing furnace 202 in a longitudinal cross-sectional view.

[0015] [ Figure 2 ] Figure 2 A schematic configuration diagram of a vertical processing furnace of a substrate processing apparatus suitable for use in one embodiment of the present disclosure is a diagram showing a part of a processing furnace 202 in a longitudinal cross-sectional view. Figure 1The AA-line cross-sectional view shows part of the processing furnace 202.

[0016] [ Figure 3 ] Figure 3 This is a schematic configuration diagram of the controller 121 of a substrate processing apparatus suitable for use in one aspect of this disclosure, and is a block diagram showing the control system of the controller 121.

[0017] [ Figure 4 ] Figure 4 (a) is a partial cross-sectional enlarged view of a surface portion of a substrate in one embodiment of the present disclosure, showing a surface having a recess. Figure 4 (b) shows the result from Figure 4 The state of (a) is a partial cross-sectional magnified view of the surface portion of the substrate in one manner of the present disclosure after implementing step A1. Figure 4 (c) is to show from Figure 4 The state of (b) is a partial cross-sectional magnified view of the surface portion of the substrate in one aspect of this disclosure after the cycle of steps A2 and A3 has been performed a predetermined number of times. Figure 4 (d) is to show from Figure 4 The state of (c) is a partial cross-sectional magnified view of the surface portion of the substrate in one aspect of this disclosure after the cycle of steps B1 and B2 has been performed a predetermined number of times. Figure 4 (e) is to show from Figure 4 The (d) state is a partial cross-sectional magnified view of the surface portion of the substrate in one manner of this disclosure after implementing step C1. Figure 4 (f) is to show from Figure 4 The state of (e) will include a partial cross-sectional magnified view of the surface portion of the substrate in one aspect of this disclosure after the cycle of steps C2 and C3 has been performed a predetermined number of times.

[0018] Explanation of reference numerals in the attached figures

[0019] 200 wafers (substrates) Detailed Implementation

[0020] <One way of publishing this text>

[0021] The following is mainly based on Figures 1-3 , Figure 4 (a)~ Figure 4 Section (f) describes one method of this disclosure. It should be noted that the accompanying drawings used in the following description are schematic, and the dimensional relationships and ratios of the elements shown in the drawings may not be consistent with reality. Furthermore, the dimensional relationships and ratios of the elements may not be consistent between multiple drawings.

[0022] (1) Configuration of substrate processing apparatus

[0023] As shown in FIG. 1, a processing furnace 202 of a substrate processing apparatus is provided with a reaction tube 203. A manifold 209 is disposed below the reaction tube 203. The processing furnace 202 is mainly composed of the reaction tube 203 and the manifold 209. A processing chamber 201 is formed inside the processing furnace 202. The processing chamber 201 is configured so as to be able to accommodate a wafer 200 as a substrate. Figure 1 A heater 207 that heats the wafer 200 inside the processing chamber 201 is provided outside the reaction tube 203. The heater 207 also functions as an activation mechanism that activates a gas inside the processing chamber 201 by heat. A temperature sensor 263 is provided inside the reaction tube 203.

[0024] Nozzles 249a to 249c are provided inside the processing chamber 201. As shown in FIG. 2, the nozzles 249a to 249c are provided so as to rise in the direction of arrangement toward the wafer 200 along the inner wall of the reaction tube 203. Gas supply holes 250a to 250c are provided on the side surfaces of the nozzles 249a to 249c from the lower portion to the upper portion of the reaction tube 203.

[0025] Figure 2 Gas supply tubes 232a to 232c are connected to the nozzles 249a to 249c. Mass flow controllers (MFCs) 241a to 241c and valves 243a to 243c are provided on the gas supply tubes 232a to 232c. Gas supply tubes 232d and 232f are connected to the gas supply tube 232a on the downstream side from the valve 243a. Gas supply tubes 232e and 232g are connected to the gas supply tube 232b on the downstream side from the valve 243b. A gas supply tube 232h is connected to the gas supply tube 232c on the downstream side from the valve 243c. MFCs 241d to 241h and valves 241d to 241h are provided on the gas supply tubes 232d to 232h.

[0026] A modifier (first and second modifiers) is supplied from the gas supply tube 232a to the processing chamber 201 via the MFC 241a, the valve 243a, and the nozzle 249a.

[0027] A film former (first and second film formers) is supplied from the gas supply tube 232b to the processing chamber 201 via the MFC 241b, the valve 243b, and the nozzle 249b.

[0028] A reactant (first to fifth reactants) is supplied from the gas supply tube 232c to the processing chamber 201 via the MFC 241c, the valve 243c, and the nozzle 249c.

[0029] A reactant (first to fifth reactants) is supplied from the gas supply tube 232c to the processing chamber 201 via the MFC 241c, the valve 243c, and the nozzle 249c.

[0030] ​The etchant is supplied from the gas supply pipe 232d to the processing chamber 201 via the MFC 241d, the valve 243d, the gas supply pipe 232a, and the nozzle 249a.

[0031] The catalyst is supplied from the gas supply pipe 232e to the processing chamber 201 via the MFC 241e, the valve 243e, the gas supply pipe 232b, and the nozzle 249b.

[0032] The non-reactive gas is supplied from the gas supply pipes 232f to 232h to the processing chamber 201 via the MFCs 241f to 241h, the valves 243f to 243h, the gas supply pipes 232a to 232c, and the nozzles 249a to 249c. The non-reactive gas functions as a purge gas, a carrier gas, a dilution gas, and the like.

[0033] The modifier supply system is mainly composed of the gas supply pipe 232a, the MFC 241a, and the valve 243a. The film former supply system is mainly composed of the gas supply pipe 232b, the MFC 241b, and the valve 243b. The reactant supply system is mainly composed of the gas supply pipe 232c, the MFC 241c, and the valve 243c. The etchant supply system is mainly composed of the gas supply pipe 232d, the MFC 241d, and the valve 243d. The catalyst supply system is mainly composed of the gas supply pipe 232e, the MFC 241e, and the valve 243e. The non-reactive gas supply system is mainly composed of the gas supply pipes 232f to 232h, the MFCs 241f to 241h, and the valves 243f to 243h. Any one or all of the above-described supply systems can be configured as an integrated supply system 248 in which the valves 243a to 243h and the MFCs 241a to 241h are integrated.

[0034] An exhaust port 231a is provided below the reaction pipe 203. On the exhaust pipe 231, a vacuum pump 246 is connected via a pressure sensor 245 and an APC (Auto Pressure Controller) valve 244. The exhaust system is mainly composed of the exhaust pipe 231, the APC valve 244, and the pressure sensor 245. The vacuum pump 246 can also be included in the exhaust system.

[0035] A seal cap 219 is provided below the manifold 209. On the seal cap 219, a rotation mechanism 267 that rotates a wafer boat 217 described later is provided. The seal cap 219 is raised and lowered by a wafer boat elevator 115. The wafer boat elevator 115 functions as a carrying mechanism that carries the wafer 200 in and out of the processing chamber 201.

[0036] A gate 219s that can airtightly seal the lower end opening of the manifold 209 is provided below the manifold 209. The opening and closing operation of the gate 219s is controlled by a gate opening and closing mechanism 115s.

[0037] The crystal boat 217, which serves as a substrate support, is constructed by arranging, in a horizontal orientation, multiple wafers 200, for example 25 to 200, in a vertical direction and supporting them in multiple layers. At the bottom of the crystal boat 217, a heat insulation plate 218 is supported in multiple layers.

[0038] like Figure 3 As shown, the controller 121, serving as the control unit, is configured as a computer including a CPU 121a, RAM 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, such as a touch panel, is connected to the controller 121. An external storage device 123 can be connected to the controller 121.

[0039] The storage device 121c is composed of flash memory, HDD, SSD, etc. The storage device 121c records and stores, in a readable manner, a control program that controls the operation of the processing device, and a process flow that describes the steps and conditions of the substrate processing described later. The process flow is formed by the controller 121 causing the processing device to execute each step of the substrate processing described later, and combining them in a way that yields a predetermined result; it functions as a program. Hereinafter, the process flow, control program, etc., will also be collectively referred to as a program (program workpiece). Furthermore, the process flow will also be referred to simply as a process. When the term "program" is used in this specification, sometimes only the process flow is included, sometimes only the control program is included, or sometimes both are included.

[0040] I / O port 121d connects to MFC241a-241h, valves 243a-243h, pressure sensor 245, APC valve 244, vacuum pump 246, temperature sensor 263, heater 207, rotating mechanism 267, crystal boat elevator 115, gate opening and closing mechanism 115s, etc. I / O port 121d can also be connected to the etching unit.

[0041] CPU 121a is configured to read and execute control programs from storage device 121c, and to read processes from storage device 121c based on input commands from input / output device 122. CPU 121a is configured to control, according to the read processes, the flow rate regulation of various substances based on MFCs 241a-241h, the opening and closing of valves 243a-243h, the opening and closing of APC valve 244, the pressure regulation based on pressure sensor 245 and APC valve 244, the start and stop of vacuum pump 246, the temperature regulation of heater 207 based on temperature sensor 263, the rotation and rotation speed regulation of crystal boat 217 based on rotation mechanism 267, the lifting and lowering of crystal boat 217 based on crystal boat elevator 115, and the opening and closing of gate 219s based on gate opening and closing mechanism 115s. CPU 121a may also be configured to control etching units.

[0042] The controller 121 is configured to install the aforementioned program, recorded and stored in the external storage device 123, into a computer. The external storage device 123 includes disks such as HDDs, optical discs such as CDs, USB drives, semiconductor storage devices such as SSDs, etc. The storage device 121c and the external storage device 123 constitute a computer-readable recording medium. Hereinafter, they will also be collectively referred to as recording media. When the term "recording medium" is used in this specification, sometimes only the storage device 121c is included, sometimes only the external storage device 123 is included, or sometimes both are included. The program can also be provided to the computer using communication means such as the Internet.

[0043] (2) Substrate processing process

[0044] Using the aforementioned substrate processing apparatus, as a step in the manufacturing process (manufacturing method) of a semiconductor device, an example of the processing sequence for forming a film in a recess provided on the surface of a wafer 200 serving as a substrate is mainly used. Figure 4 (a)~ Figure 4 (f) will be explained below. The series of processing steps shown below is implemented by the substrate processing apparatus described above. At this time, the operation of each part constituting the substrate processing apparatus is controlled by the controller 121.

[0045] In the processing order of this method, the following steps are performed:

[0046] (a) Step A, in which a first film-forming agent is supplied to a wafer 200 having a recess having a bottom surface formed of a first substrate and a side surface formed of a second substrate, to selectively form a first film on the first substrate in a manner thicker than the first film formed on the second substrate; and

[0047] (b) Step B, in which an etchant is supplied to the wafer 200 to remove the first film formed on the second substrate while leaving at least a portion of the first film formed on the first substrate remaining. Figure 4 (a) shows the state (initial state) of the recess in the surface of the wafer 200, which is the object of processing.

[0048] It should be noted that, in the following example, the following situation is described: In step A, before the first film-forming agent is supplied to the wafer 200, step A1 is performed to supply the first modifier to the wafer 200, selectively modifying the surface of the second substrate relative to the surface of the first substrate to form a surface with a first capping end that inhibits at least a portion of the adsorption of the first film-forming agent. Figure 4 (b) shows from Figure 4 The state shown in (a) is the state inside the recess after step A1.

[0049] Additionally, in the following example, the following situation will be explained: In step A, after performing step A1, a loop including the following steps will be performed a specified number of times (n). A Next, n A (integers greater than or equal to 1)

[0050] (a2) Step A2 of supplying the first film-forming agent to wafer 200; and

[0051] (a3) Step A3 of supplying the first reactant to the wafer 200.

[0052] Figure 4 (c) shows from Figure 4 The state shown in (b) is the state within the recess after the cycle of steps A2 and A3 has been performed a specified number of times.

[0053] Additionally, in the following example, the following situation will be explained: In step B, the loop including the following steps will be performed a specified number of times (n). B Next, n B (integers greater than or equal to 1)

[0054] (b1) Step B1 of supplying the second reactant that reacts with the first membrane to wafer 200; and

[0055] (b2) Step B2, which supplies the wafer 200 with an etchant that is a substance different from the second reactant.

[0056] Figure 4 (d) shows from Figure 4 The state shown in (c) is the state within the recess after the cycle of steps B1 and B2 has been performed a specified number of times.

[0057] In the following examples, the case where, after step B, step C is performed is described.

[0058] (c) a step C of supplying the wafer 200 with a second film former to form a second film different in composition from the first film on the first film.

[0059] In the following examples, the case where, in step C, before the wafer 200 is supplied with the second film former, step C1 is performed is described.

[0060] (c1) a step C1 of supplying the wafer 200 with a second modifier to selectively modify the surface of the second substrate to a second capped surface on which at least a part of the second film former is inhibited from adsorbing, with respect to the surface of the first substrate. Figure 4 (f) shows the state in the recess after step C1 is performed from the state shown in (e). Figure 4 (f) shows the state in the recess after step C1 is performed from the state shown in (e).

[0061] In the following examples, the case where, in step C, after step C1 is performed, a cycle including the following steps is performed a prescribed number of times (n c times, n c is an integer of 1 or more),

[0062] (c2) a step C2 of supplying the wafer 200 with the second film former; and

[0063] (c3) a step C3 of supplying the wafer 200 with a third reactant.

[0064] Figure 4 (f) shows the state in the recess after a cycle including steps C2 and C3 is performed a prescribed number of times from the state shown in (e). Figure 4 (f) shows the state in the recess after a cycle including steps C2 and C3 is performed a prescribed number of times from the state shown in (e).

[0065] In the present disclosure, the above-described processing sequence is sometimes also shown as follows.

[0066] Step A: first modifier → (first film former → first reactant) × nA

[0067] Step B: (second reactant → etching agent) × nB

[0068] Step C: second modifier → (second film former → third reactant) × nc

[0069] The term "wafer" used in this specification sometimes refers to a wafer itself and sometimes refers to a layered body of a wafer and a prescribed layer, film formed on the surface thereof. The term "surface of a wafer" used in this specification sometimes refers to a surface of a wafer itself and sometimes refers to a surface of a prescribed layer or the like formed on a wafer. In the case where it is described in this specification that a prescribed layer is formed on the surface of a wafer, it sometimes refers to a case where the prescribed layer is formed directly on the surface of the wafer itself and sometimes refers to a case where the prescribed layer is formed on a layer or the like formed on the wafer. The term "substrate" used in this specification is used synonymously with the term "wafer".

[0070] The term "agent", "substance" used in this specification includes at least either one of a gaseous substance and a liquid substance. The liquid substance includes a mist-like substance. That is, each of the modification agent, the film forming agent, the reactant, the etching agent, the catalyst described later can include a gaseous substance, can include a liquid substance such as a mist-like substance, or can include both of them.

[0071] Hereinafter, the processing sequence in the present embodiment will be described in detail.

[0072] (Wafer loading and boat loading)

[0073] If a plurality of wafers 200 are loaded (wafer loading) into the boat 217, the gate 219s is moved by the gate opening / closing mechanism 115s, and the lower end opening of the manifold 209 is opened (gate opening). Then, as shown in FIG. 2B, the boat 217 on which the plurality of wafers 200 are supported is lifted by the boat lifter 115 and carried into the processing chamber 201 (boat loading). In this state, the seal cap 219 is in a state of sealing the lower end of the manifold 209 via the O-ring 220b. Figure 1

[0074] The wafer 200 to be processed has a three-dimensional structure, i.e., a recess, such as a groove, a hole, on the surface. As shown in (a) of FIG. 3, the recess has a bottom surface composed of a first base and a side surface composed of a second base. Such a structure can be formed by a known method, for example, by forming a layered structure of the second base / sacrificial film / second base on the surface of the wafer 200, patterning the layered structure, then forming the first base on the side surface thereof, and then using an etching solution having a prescribed etching selectivity to selectively etch only the sacrificial film while suppressing etching of the first base and the second base. Figure 4

[0075] The first base is sometimes composed of a material containing a nonmetallic element, particularly a semimetallic element (Si, B, Ge, As, Sb, Te, etc.) and nitrogen (N), such as silicon nitride (SiN), silicon carbon nitride (SiCN), silicon boron nitride (SiBN), silicon boron carbon nitride (SiBCN), etc.​​

[0076] The second base is sometimes made of a material containing a nonmetal element (particularly a semimetal element) and oxygen (O), such as silicon oxide (SiO), silicon oxynitride (SiON), silicon oxycarbide (SiOC), silicon oxycarbonitride (SiOCN), silicon boron oxynitride (SiBON), silicon boron oxycarbonitride (SiBCON), and the like.

[0077] In addition, the second base is sometimes made of a material containing a metal element (Al, Ti, Zr, Hf, Ta, Mo, and the like), a nonmetal element (particularly a semimetal element), and O, such as aluminum silicon oxide (AlSiO), titanium silicon oxide (TiSiO), zirconium silicon oxide (ZrSiO), hafnium silicon oxide (HfSiO), tantalum silicon oxide (TaSiO), molybdenum silicon oxide (MoSiO), and the like.

[0078] In addition, the second base is sometimes made of a material containing a metal element and O, such as aluminum oxide (AlO), titanium oxide (TiO), zirconium oxide (ZrO), hafnium oxide (HfO), tantalum oxide (TaO), molybdenum oxide (MoO), zirconium aluminum oxide (ZrAlO), hafnium aluminum oxide (HfAlO), and the like.

[0079] (Pressure regulation and temperature regulation)

[0080] After the end of the boat loading, vacuum evacuation (depressurization evacuation) is performed by the vacuum pump 246 to make the inside of the processing chamber 201, i.e., the space in which the wafer 200 exists, a desired pressure (degree of vacuum). At this time, the pressure in the processing chamber 201 is measured by the pressure sensor 245, and feedback control is performed on the APC valve 244 based on the measured pressure information. In addition, heating is performed by the heater 207 to make the wafer 200 in the processing chamber 201 a desired processing temperature. At this time, based on the temperature information detected by the temperature sensor 263, the energization to the heater 207 is feedback controlled to make the inside of the processing chamber 201 a desired temperature distribution. In addition, the rotation of the wafer 200 by the rotation mechanism 267 is started. The evacuation of the inside 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 ends.

[0081] (Step A)

[0082] Next, the wafer 200 prepared in the processing chamber 201 is subjected to the following steps A1 to A3.

[0083] [Step A1]

[0084] In this step, valve 243a is opened, allowing the modifier (first modifier) ​​to flow into gas supply pipe 232a. The first modifier is regulated by MFC 241a, supplied to processing chamber 201 via nozzle 249a, and vented from exhaust port 231a. At this time, the first modifier is supplied to wafer 200 from the side, exposing wafer 200 to the first modifier (first modifier supply, exposure). At this time, valves 243f to 243h can be opened, supplying inactive gas into processing chamber 201 via nozzles 249a to 249c respectively.

[0085] By performing this step under the processing conditions described later, thus achieving... Figure 4 As shown in (b), at least a portion of the molecular structure constituting the first modifier can be selectively adsorbed on the surface of the second substrate relative to the surface of the first substrate, forming a defined adsorption layer (first inhibitor layer). By using the substance described later as the first modifier and forming the first inhibitor layer on the surface of the second substrate, the surface of the second substrate relative to the surface of the first substrate is selectively modified into a surface capped by alkyl groups, hydrogen (H), or fluorine (F). These cappings (alkyl capping, H capping, F capping) function as inhibitors in step A2 described later, suppressing the adsorption of the first film-forming agent onto the surface of the second substrate. That is, by performing this step, the surface of the second substrate relative to the surface of the first substrate is selectively modified into a surface with first cappings that suppress the adsorption of at least a portion of the first film-forming agent.

[0086] It should be noted that the statement "the surface of the second substrate is selectively modified relative to the surface of the first substrate" in this disclosure does not mean "only the surface of the second substrate is modified," but rather that "the surface of the second substrate is preferentially modified, among the surfaces of the first substrate and the second substrate." That is, the expression "selectively" indicates the relative magnitude of the degree of modification of the surface of the second substrate relative to the degree of modification of the surface of the first substrate, and does not completely exclude the modification of the surface of the first substrate. This expression "selectively" will be used with substantially the same meaning in the following steps.

[0087] After selectively modifying the surface of the second substrate, valve 243a is closed to stop the supply of the first modifier to the wafer 200. Then, vacuum exhaust is performed in the processing chamber 201 to remove gaseous substances and other residues remaining in the processing chamber 201. Additionally, valves 243f to 243h are opened to supply inactive gas into the processing chamber 201 for purging.

[0088] Examples of processing conditions for supplying the first modifier in step A1 include:

[0089] Treatment temperature: room temperature (25°C) to 500°C, preferably room temperature to 250°C

[0090] Treatment pressure: 1 to 2000 Pa, preferably 1 to 1000 Pa

[0091] Treatment time: 1 second to 120 minutes, preferably 30 seconds to 60 minutes

[0092] First modifier supply flow rate: 0.001 to 3 slm, preferably 0.001 to 0.5 slm

[0093] Non-reactive gas supply flow rate (per gas supply pipe): 0 to 20 slm

[0094] Note that the expression of a numerical range such as "25 to 500°C" in this specification means that the lower limit value and the upper limit value are included in the range. Thus, for example, "25 to 500°C" means "25°C or higher and 500°C or lower". The same applies to other numerical ranges. In addition, the treatment temperature in this specification means the temperature of the wafer 200 or the temperature in the processing chamber 201, and the treatment pressure means the pressure in the processing chamber 201. In addition, the treatment time means the time during which the processing is continued. In addition, in the case where the supply flow rate includes 0 slm, 0 slm means the case where the substance is not supplied. The same applies to the following description.

[0095] As the first modifier, for example, a substance in which hydrogen (H) and an amino group are bonded to Si, such as tris(dimethylamino)silane (Si[N(CH3)2]3H), bis(dimethylamino)silane (Si[N(CH3)2]2H2), bis(tert-butylamino)silane (SiH2[NH(C4H9)]2), (diisobutylamino)silane (SiH3[N(C4H9)2]), (diisopropylamino)silane (SiH3[N(C3H7)2]), and the like, can be used.

[0096] In addition, as the first modifier, for example, a substance in which an amino group and a hydrocarbon group are bonded to Si, such as (dimethylamino)trimethylsilane ((CH3)2NSi(CH3)3), (diethylamino)triethylsilane ((C2H5)2NSi(C2H5)3), (dimethylamino)triethylsilane ((CH3)2NSi(C2H5)3), (diethylamino)trimethylsilane ((C2H5)2NSi(CH3)3), (dipropylamino)trimethylsilane ((C3H7)2NSi(CH3)3), and the like, can be used.

[0097] Further, as the first modifier, for example, a substance containing a halogen element such as fluorine (F), chlorine (Cl), bromine (Br), iodine (I) or the like can be used. As the substance containing a halogen element used as the first modifier, for example, a fluorine (F)-containing substance such as fluorine (F2), nitrogen trifluoride (NF3), chlorine trifluoride (CIF3), chlorine fluoride (CIF), hydrogen fluoride (HF) or the like can be used.

[0098] As the first modifier, one or more of these can be used.

[0099] As the non-active gas, for example, a rare gas such as nitrogen (N2) gas, argon (Ar) gas, helium (He) gas, neon (Ne) gas, xenon (Xe) gas or the like can be used. As the non-active gas, one or more of these can be used. This is also the same in each of the steps described later.

[0100] [Step A2]

[0101] In this step, the valve 243b is opened, and a film forming agent (first film forming agent) is caused to flow into the gas supply pipe 232b. The first film forming agent is flow-regulated by the MFC 241b, supplied into the processing chamber 201 via the nozzle 249b, and exhausted from the exhaust port 231a. At this time, the first film forming agent is supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the first film forming agent (first film forming agent supply, exposure). At this time, the valves 243f to 243h can be opened, and a non-active gas can be supplied into the processing chamber 201 via each of the nozzles 249a to 249c.

[0102] By performing this step under the processing conditions described later, at least a part of the molecular structure of the molecules constituting the first film forming agent is adsorbed to the surface of each of the first substrate and the second substrate, and an adsorption layer (first layer) of the first film forming agent is formed on these surfaces. As described above, by performing the step Al, the surface of the second substrate is modified to a surface on which the first capping is formed (a surface having a film formation hindering effect). Thus, the amount of adsorption of the first film forming agent per unit area and unit time on the first substrate becomes more than the amount of adsorption of the first film forming agent per unit area and unit time on the second substrate. That is, the thickness of the first layer formed on the first substrate becomes thicker than the thickness of the first layer formed on the second substrate.

[0103] After the first layer is formed on the first substrate in a manner thicker than the thickness of the first layer formed on the second substrate, the valve 243a is closed, and the supply of the first film forming agent to the wafer 200 is stopped. Then, by using the steps described above, the gaseous substance or the like remaining in the processing chamber 201 is exhausted from the processing chamber 201, and the processing chamber 201 is purged with a non-active gas (purging).

[0104] As the processing conditions when the first film forming agent is supplied in the step A2, for example, the following can be exemplified:

[0105] Treatment temperature: room temperature (25°C) to 500°C, preferably 350 to 400°C;

[0106] Treatment pressure: 1 to 2000 Pa, preferably 1 to 1333 Pa;

[0107] Treatment time: 1 to 180 seconds, preferably 10 to 120 seconds;

[0108] First film forming agent supply flow rate: 0.001 to 2 slm, preferably 0.01 to 1 slm;

[0109] Non-reactive gas supply flow rate (per gas supply pipe): 0 to 20 slm.

[0110] As the first film forming agent, for example, a substance (e.g., organometal or halogenated metal) containing a metal element of aluminum (Al), titanium (Ti), hafnium (Hf), zirconium (Zr), or the like as the first prescribed element can be used. As the first film forming agent, for example, aluminum trichloride (AlCl3), trimethylaluminum (Al(CH3)3), titanium tetrachloride (TiCl4), hafnium tetrachloride (HfCl4), hafnium tetraethylmethylamino (Hf[N(CH3)(CH2CH3)]4), zirconium tetrachloride (ZrCl4), zirconium tetraethylmethylamino (Zr[N(CH3)Cp]4), or the like can be used.

[0111] [Step A3]

[0112] In this step, the valve 243c is opened, and a reactant (first reactant) is flowed into the gas supply pipe 232c. The first reactant is flow rate-adjusted by the MFC 241c, supplied into the processing chamber 201 via the nozzle 249c, and exhausted from the exhaust port 231a. At this time, the first reactant is supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the first reactant (first reactant supply, exposure). At this time, the valves 243f to 243h can be opened, and a non-reactive gas can be supplied into the processing chamber 201.

[0113] By performing this step under the processing conditions described later, the first layer formed on the surface of each of the first substrate and the second substrate can be changed. For example, in a case where an oxidizing agent is used as the first reactant, at least a part of the first layer can be oxidized, and an oxide layer (first oxide layer) containing a constituent element of the first film forming agent can be formed on the surface of each of the first substrate and the second substrate. Also for example, in a case where a nitriding agent is used as the first reactant, at least a part of the first layer can be nitrided, and a nitride layer (first nitride layer) containing a constituent element of the first film forming agent can be formed on the surface of each of the first substrate and the second substrate.

[0114] After the first layer formed on the surfaces of the first and second substrates is changed, valve 243c is closed to stop the supply of reactants to wafer 200. Then, through the above steps, gaseous substances and the like remaining in the processing chamber 201 are removed from the processing chamber 201 by purging the processing chamber 201 with an inactive gas.

[0115] Examples of processing conditions for supplying the first reactant in step A3 include:

[0116] Processing pressure: 1–4000 Pa, preferably 1–1333 Pa;

[0117] The first reactant supply flow rate is 0.01–20 slm, preferably 0.01–10 slm.

[0118] Other processing conditions can be set to be the same as those in step A2 when the first film-forming agent is supplied.

[0119] An oxidizing agent can be used as the first reactant. Examples of oxidizing agents include oxygen (O2), ozone (O3), water vapor (H2O), nitrous oxide (N2O), nitric oxide (NO), nitrogen dioxide (NO2), carbon dioxide (CO2), and carbon monoxide (CO). One or more of these oxygen-containing (O) substances can be used as the first reactant.

[0120] Additionally, a nitriding agent can be used as the first reactant. Examples of nitriding agents include hydrogen nitride such as ammonia (NH3), diazoxide (N2H2), hydrazine (N2H4), and N3H8. One or more of these nitrogen-containing (N) substances can be used as the first reactant.

[0121] [Number of times stipulated for implementation]

[0122] Then, the loop including steps A2 and A3 will be performed a specified number of times (n). A Next. A (Integers of 1 or 2 or higher). Therefore, as... Figure 4 As shown in (c), a first film can be formed on the respective surfaces of the first substrate and the second substrate. As described above, in step A2, the thickness of the first layer formed on the first substrate becomes thicker than the thickness of the first layer formed on the second substrate. Therefore, by performing the cycle including steps A2 and A3 a predetermined number of times, the thickness of the first film formed on the first substrate becomes thicker than the thickness of the first film formed on the second substrate.

[0123] When a substance containing the aforementioned metal element is used as the first film-forming agent, a film containing the aforementioned metal element can be formed as the first film.

[0124] Further, in a case where a substance containing the above metal element is used as the first film forming agent and the above oxidizing agent is used as the first reactant, the above film containing the metal element and O (i.e., a metal oxide film) can be formed as the first film. In this mode, as the first film, for example, an oxide dielectric film (oxide high-k film) having a larger electron trapping density than a SiN film, such as an aluminum oxide film (AlO film), a titanium oxide film (TiO film), a hafnium oxide film (HfO film), a zirconium oxide film (ZrO film), and the like, can be formed as a more suitable example.

[0125] Further, in a case where a substance containing the above metal element is used as the first film forming agent and the above nitriding agent is used as the first reactant, a film containing the metal element and N (i.e., a metal nitride film) can be formed as the first film. In this mode, as the first film, for example, a nitride dielectric film (nitride high-k film) having a larger electron trapping density than a SiN film, such as an aluminum nitride film (AlN film), a titanium nitride film (TiN film), a hafnium nitride film (HfN film), a zirconium nitride film (ZrN film), and the like, can be formed as a more suitable example.

[0126] (Step B)

[0127] Next, the following steps B1 and B2 are performed.

[0128] [Step B1]

[0129] In this step, the valve 243c is opened, and a reactant (second reactant) is caused to flow into the gas supply pipe 232c. The second reactant is flow-regulated by the MFC 241c, supplied into the processing chamber 201 via the nozzle 249c, and exhausted from the exhaust port 231a. At this time, the second reactant is supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the second reactant (second reactant supply, exposure). At this time, the valves 243f to 243h can be opened, and a non-reactive gas can be supplied into the processing chamber 201.

[0130] By performing this step under the processing conditions described later, the surface of the first film formed in the recess in Step A is caused to react with the second reactant, and a modified layer having a prescribed composition and a prescribed thickness can be formed on the surface of the first film. For example, in a case where the first film is composed of an aluminum oxide film (AlO film) having aluminum oxide (Al2O3) as a main component, by supplying a substance containing boron (B) and a halogen element as the second reactant to this film, the first film can be caused to react with the second reactant, and a portion of the surface of the first film can be modified (converted) into a modified layer containing an aluminum halide (e.g., AlCl3 or the like) having a prescribed thickness. This reaction can be performed uniformly in substantially the entire region of the surface of the first film, and the composition and thickness of the modified layer are substantially uniform in the entire surface region of the first film.

[0131] After the modified layer is formed on the surface of the first film by the reaction with the second reactant, the valve 243d is closed, and the supply of the second reactant to the wafer 200 is stopped. Then, the inside of the processing chamber 201 is vacuum-exhausted, and the gaseous substance or the like remaining in the processing chamber 201 is exhausted from the processing chamber 201. In addition, the valves 243f to 243h are opened, and the non-reactive gas is supplied to the inside of the processing chamber 201, and the inside of the processing chamber 201 is purged (purging).

[0132] As the processing conditions at the time of supplying the second reactant in the step B1, for example, the following can be exemplified.

[0133] Processing temperature: 200 to 900°C, preferably 300 to 800°C;

[0134] Processing pressure: 150 to 400 Pa, preferably 200 to 300 Pa;

[0135] Processing time: 5 to 300 seconds, preferably 100 to 200 seconds;

[0136] Flow rate of the second reactant: 0.001 to 2 slm, preferably 0.01 to 1 slm;

[0137] Flow rate of the non-reactive gas (per gas supply pipe): 0 to 20 slm.

[0138] As the second reactant, for example, boron trichloride (BC13), boron trifluoride (BF3), boron tribromide (BBr3), boron triiodide (BI3), or the like can be used. As the second reactant, one or more of these substances containing B and halogen elements can be used.

[0139] [Step B2]

[0140] In this step, the valve 243d is opened, and the etchant is flowed into the gas supply pipe 232d. The etchant is flow-regulated by the MFC 241d, supplied to the inside of the processing chamber 201 via the nozzle 249a, and exhausted from the exhaust port 231a. At this time, the etchant is supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the etchant (etchant supply, exposure). At this time, the valves 243f to 243h can be opened, and the non-reactive gas can be supplied to the inside of the processing chamber 201.

[0141] By carrying out this step under the processing conditions described later, the modified layer formed on the surface of the first film is caused to react with the etchant, and at least a part of the modified layer is converted into a volatile substance, which is caused to separate from the surface of the first film. For example, in the case where the modified layer containing aluminum halide is formed on the surface of the first film, by supplying a halogen-containing substance different from the second reactant as the etchant to the film, the modified layer is caused to react with the etchant, and at least a part of the modified layer is converted into other aluminum halide (e.g., AICI x F y etc.) as a volatile substance, which is caused to separate from the first film. Thereby, the surface of the first film is etched with a substantially uniform thickness over the entire area thereof in-plane. The etching amount (etching depth) of the first film formed on the first substrate and the etching amount (etching depth) of the first film formed on the second substrate become substantially equal.

[0142] After etching the surface of the first film, the valve 243c is closed, and the supply of the etchant to the wafer 200 is stopped. Then, the processing chamber 201 is vacuum-exhausted, and the gaseous substance or the like remaining in the processing chamber 201 is excluded from the processing chamber 201. In addition, the valves 243f to 243h are opened, and the non-active gas is supplied to the processing chamber 201, and the processing chamber 201 is purged (purging).

[0143] As the processing conditions at the time of supplying the etchant in step B2, for example,

[0144] Processing time: 5 to 200 seconds, preferably 60 to 150 seconds;

[0145] Etchant supply flow rate: 0.1 to 10 slm;

[0146] Non-active gas supply flow rate (for each gas supply pipe): 0 to 20 slm.

[0147] The other processing conditions can be set to be the same as the processing conditions at the time of supplying the second reactant in step Bl.

[0148] As the etchant, for example, a halogen-containing substance can be used. As the halogen-containing substance used as the etchant, for example, HF, F2, Cl2, NF3, ClF3, ClF, or the like can be used. As the etchant, one or more of these halogen-containing substances can be used.

[0149] [Implementation of a predetermined number of times]

[0150] Then, the cycle including steps Bl and B2 is carried out a predetermined number of times (n B times. n B is an integer of 1 or more). Thereby, as Figure 4As shown in (d), the first film formed on the second substrate can be removed while at least a portion of the first film formed on the first substrate remains. This is possible because, as described above, in step A, the thickness of the first film formed on the first substrate is greater than the thickness of the first film formed on the second substrate, and in step B, the etching amount (etching depth) of the first film formed on the first substrate is approximately equal to the etching amount (etching depth) of the first film formed on the second substrate.

[0151] (Step C)

[0152] Next, proceed with the following steps C1 to C3.

[0153] [Step C1]

[0154] In this step, using the same processing steps and conditions as in step A1 above, a modifier (second modifier) ​​is supplied to the wafer 200 (second modifier supply and exposure).

[0155] By performing this step under the processing conditions described later, thus achieving... Figure 4 As shown in (e), at least a portion of the molecular structure constituting the second modifier can be selectively adsorbed onto the surface of the second substrate exposed by removing the first film, relative to the surface of the first film remaining on the first substrate, forming a predetermined adsorption layer (the second inhibitor layer). By using the substance exemplified as the first modifier in step A1 as the second modifier and forming the second inhibitor layer on the surface of the second substrate, the surface of the second substrate is selectively modified relative to the surface of the first film remaining on the first substrate to a surface capped with hydrocarbon groups, H, F, etc. These cappings (hydrocarbon capping, H capping, F capping, etc.) function as inhibitors in step C2 described later, suppressing the adsorption of the second film-forming agent onto the surface of the second substrate. That is, by performing this step, the surface of the second substrate is selectively modified relative to the surface of the first film remaining on the first substrate to a surface with second cappings that suppress the adsorption of at least a portion of the second film-forming agent.

[0156] Note that in the case where both the 2nd substrate and the 1st film are composed of an oxide, it is sometimes difficult to exhibit the selectivity described above. Therefore, in order to improve the selectivity, it is preferable to make the density of the material constituting the 2nd substrate higher than the density of the 1st film. By making the density of the material constituting the 2nd substrate relatively high, it is possible to make the density of the end-capping of the adsorption sites (e.g., hydroxyl (OH group) and the like) of the 2nd modifier on the surface of the 2nd substrate larger than the density of the end-capping of the adsorption sites of the 2nd modifier on the surface of the 1st film. That is, thereby, it is possible to improve the selectivity of the adsorption of the 2nd modifier to the surface of the 2nd substrate as compared to the adsorption to the surface of the 1st film. As a method of making the density of the material constituting the 2nd substrate relatively higher than the density of the 1st film, for example, it is preferable to make the processing temperature at the time of forming the 2nd substrate higher than the processing temperature at the time of forming the 1st film (i.e., the processing temperature in Step A).

[0157] After selectively modifying the surface of the 2nd substrate, the valve 243a is closed, and the supply of the 2nd modifier to the wafer 200 is stopped. Then, the inside of the processing chamber 201 is vacuum-exhausted, and the gaseous substance or the like remaining in the processing chamber 201 is exhausted from the processing chamber 201. In addition, the valves 243f to 243h are opened, and the non-active gas is supplied to the inside of the processing chamber 201, and the inside of the processing chamber 201 is purged (purging).

[0158] [Step C2]

[0159] In this step, the valves 243b, 243e are opened, and the film-forming agent (2nd film-forming agent), the catalyst are respectively flowed into the gas supply pipes 232b, 232e. The 2nd film-forming agent and the catalyst are flow-regulated by the MFCs 241b, 241e, supplied to the inside of the processing chamber 201 via the nozzles 249b, and exhausted from the exhaust port 231a. At this time, the 2nd film-forming agent and the catalyst are supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the 2nd film-forming agent and the catalyst (2nd film-forming agent + catalyst supply, exposure). At this time, it is possible to open the valves 243f to 243h, and supply the non-active gas to the inside of the processing chamber 201.

[0160] By performing this step under the processing conditions described later, it is possible to selectively adsorb at least a part of the molecular structure of the molecules constituting the 2nd film-forming agent on the surface of the 1st film remaining on the 1st substrate, and it is possible to selectively form the adsorption layer (2nd layer) of the 2nd film-forming agent. As described above, by performing Step C1, the surface of the 2nd substrate is modified to a surface on which the 2nd end-capping is formed (a surface having a film formation hindering effect). Thereby, the formation of the 2nd layer is selectively performed on the surface of the 1st film remaining on the 1st substrate with respect to the 2nd substrate.

[0161] After selectively forming the second layer on the surface of the first film, the valves 243b and 243e are closed, and the supply of the second film forming agent and the catalyst to the wafer 200 is stopped. Then, the gas-like substance and the like remaining in the processing chamber 201 are exhausted from the processing chamber 201 by the above-described steps, and the processing chamber 201 is purged with the non-reactive gas (purging).

[0162] As the processing conditions at the time of supplying the second film forming agent and the catalyst in step C2, for example, the following can be given:

[0163] Processing temperature: room temperature (25°C) to 200°C, preferably room temperature to 150°C;

[0164] Processing pressure: 1 to 2000 Pa, preferably 1 to 1333 Pa;

[0165] Processing time: 1 to 180 seconds, preferably 10 to 120 seconds;

[0166] Flow rate of the second film forming agent: 0.001 to 2 slm, preferably 0.01 to 1 slm;

[0167] Flow rate of the catalyst: 0.001 to 2 slm, preferably 0.01 to 1 slm;

[0168] Flow rate of the non-reactive gas (per gas supply pipe): 0 to 20 slm.

[0169] As the second film forming agent, a substance containing a second prescribed element, particularly a non-metal element (including a semi-metal element) can be used. As the second film forming agent, for example, a Si-containing substance containing silicon (Si) as the second prescribed element can be used. As the second film forming agent, for example, a substance containing a halogen element and Si, that is, a halosilane can be used. As the halosilane, for example, a substance containing Cl and Si, that is, chlorosilane can be used.

[0170] As the second film forming agent, for example, monochlorosilane (SiH3Cl), dichlorosilane (SiH2Cl2), trichlorosilane (SiHCl3), tetrachlorosilane (SiCl4), hexachloroethysilane (Si2Cl6), octachloropropylsilane (Si3Cl8), and the like chlorosilanes, tetrafluorosilane (SiF4), difluorosilane (SiH2F2), and the like fluorosilanes, tetrabromosilane (SiBr4), dibromosilane (SiH2Br2), and the like bromosilanes, tetraiodosilane (SiI4), diiodosilane (SiH2I2), and the like iodosilanes can be used.

[0171] As the second film-forming agent, in addition to the above, for example, a substance containing an amino group and Si, i.e., an amino silane can be used. As the second film-forming agent, for example, tetra(dimethylamino)silane (Si[N(CH3)2]4), tri(dimethylamino)silane, bis(diethylamino)silane, bis(tert-butylamino)silane, (diisopropylamino)silane, or the like can be used.

[0172] As the second film-forming agent, one or more of these can be used.

[0173] As the catalyst, for example, pyridine (C5H5N), methylpyridine (C6H7N), dimethylpyridine (C7H9N), triethylamine ((C2H5)3N), or the like can be used. As the catalyst, one or more of these amines can be used.

[0174] [Step C3]

[0175] In this step, the valves 243c, 243e are opened, and the reactant (third reactant) and the catalyst are caused to flow into the gas supply pipes 232c, 232e, respectively. The third reactant and the catalyst are flow-regulated by the MFCs 241c, 241e, supplied into the processing chamber 201 via the nozzles 249c, 249b, and exhausted from the exhaust port 231a. At this time, the third reactant and the catalyst are supplied to the wafer 200 from the side of the wafer 200, and the wafer 200 is exposed to the third reactant and the catalyst (third reactant + catalyst supply, exposure). At this time, the valves 243f to 243h can be opened, and a non-reactive gas can be supplied into the processing chamber 201.

[0176] By performing this step under the processing conditions described later, the second layer formed on the surface of the first film remaining on the first substrate can be changed. For example, in the case where an oxidizing agent is used as the third reactant, at least a part of the second layer can be oxidized, and an oxide layer (second oxide layer) containing the constituent element of the second film-forming agent can be formed on the surface of the first film remaining on the first substrate. Further, for example, in the case where a nitriding agent is used as the third reactant, at least a part of the second layer can be nitrided, and a nitride layer (second nitride layer) containing the constituent element of the second film-forming agent can be formed on the surface of the first film remaining on the first substrate.

[0177] After the second layer selectively formed on the surface of the first film is changed, the valves 243c, 243e are closed, and the supply of the third reactant and the catalyst to the wafer 200 is stopped. Then, by the above-described steps, the gaseous substance or the like remaining in the processing chamber 201 is exhausted from the processing chamber 201, and the processing chamber 201 is purged with a non-reactive gas.

[0178] As the processing conditions at the time of supplying the reactant and the catalyst in Step C3, for example, the following can be exemplified:

[0179] Processing pressure: 1–4000 Pa, preferably 1–1333 Pa;

[0180] The third reactant supply flow rate is 0.001–2 slm, preferably 0.01–1 slm.

[0181] Catalyst supply flow rate: 0.001-2 slm, preferably 0.01-1 slm.

[0182] Other processing conditions can be set to be the same as those in step C2 when the film-forming agent and catalyst are supplied.

[0183] As the third reactant, one or more of the oxidizing agents and nitriding agents exemplified in step A3 can be used.

[0184] As a catalyst, more than one of the catalysts exemplified in step C2 may be used.

[0185] [Number of times stipulated for implementation]

[0186] Then, the loop including steps C2 and C3 will be performed a specified number of times (n). C Next. C (Integers of 1 or 2 or higher). Therefore, as... Figure 4 Figure 4 As shown in (f), a second film can be formed on the first film remaining on the first substrate. As described above, in step C2, the second layer is selectively formed on the surface of the first film remaining on the first substrate, relative to the second substrate. Therefore, with regard to the formation of the second film resulting from performing the cycle including steps C2 and C3 a predetermined number of times, the formation is selectively performed on the surface of the first film remaining on the first substrate, relative to the second substrate.

[0187] When the above-mentioned substance containing non-metallic elements, especially semi-metallic elements, is used as the second film-forming agent, a film with a different composition than the first film, that is, a film containing non-metallic elements such as Si, can be formed as the second film.

[0188] Furthermore, when using the aforementioned substance containing non-metallic elements as the second film-forming agent and the aforementioned oxidant as the third reactant, as the second film, for example, SiO film, SiON film, SiOC film, SiOCN film, SiBON film, SiBCON film, and other Si-containing oxide films (films containing non-metallic elements and O) can be formed.

[0189] Furthermore, when using the aforementioned substance containing non-metallic elements as the second film-forming agent and the aforementioned nitriding agent as the third reactant, a Si-containing nitriding film (containing non-metallic elements and N) can be formed as the second film, for example, such as a SiN film, a SiCN film, or a SiBCN film.

[0190] (post-purge and atmospheric pressure recovery)

[0191] After the end of Step C, inactive gas is supplied as purge gas from each of the nozzles 249a to 249c into the processing chamber 201, and is exhausted from the exhaust port 231a. Thereby, the processing chamber 201 is purged, and gas, reaction by-products, and the like remaining in the processing chamber 201 are removed from the processing chamber 201 (post-purge). Then, the atmosphere in the processing chamber 201 is replaced with inactive gas (inactive gas replacement), and the pressure in the processing chamber 201 is returned to the normal pressure (atmospheric pressure recovery).

[0192] (cassette unloading and wafer extraction)

[0193] Then, the seal cap 219 is lowered by the cassette elevator 115, and the lower end opening of the manifold 209 is opened. Then, the processed wafer 200 is carried out (cassette unloading) from the lower end of the manifold 209 to the outside of the reaction tube 203 in a state of being supported by the cassette 217. After the cassette unloading, the gate 219s is moved, and the lower end opening of the manifold 209 is sealed by the gate 219s via the O-ring 220c (gate closing). After the processed wafer 200 is carried out to the outside of the reaction tube 203, the wafer is extracted (wafer extraction) from the cassette 217.

[0194] Steps A to C are preferably performed in the same processing chamber, or in a plurality of processing chambers connected via a transport chamber under vacuum or a non-oxidizing atmosphere (i.e., in-situ). If the series of processes are performed in-situ, the wafer 200 is not exposed to the atmosphere midway, and the wafer 200 can be continuously processed in a state of being placed under vacuum or a non-oxidizing atmosphere, and can be processed without causing natural oxidation of the surface or the like.

[0195] (3) Effects brought by the present embodiment

[0196] According to the present embodiment, one or more of the following effects can be obtained.

[0197] (a) By performing the above-described Steps A and B, it is possible to precisely form a film in the recess provided on the substrate surface. That is, in the recess including a bottom surface composed of the first base and a side surface composed of the second base, it is possible to selectively form the first film on the first base with respect to the second base.

[0198] (b) By performing the cycle including Steps Bl and B2 in Step B for a prescribed number of times, it is possible to selectively remove the first film from the second base with good controllability, with at least a part of the first film formed on the first base remaining. That is, it is possible to more precisely perform the selective formation of the first film on the first base.

[0199] (c) By performing step Al in step A, in which the surface of the second base is modified to form a surface with the first end cap before the first film forming agent is supplied to the substrate, the first film is easily formed on the first base in a manner thicker than the thickness of the first film formed on the second base. As a result, the selective formation of the first film on the first base is performed more precisely.

[0200] (d) By performing the cycle including steps A2 and A3 a prescribed number of times after step Al in step A, the thickness of the first film formed in the recesses can be precisely controlled. As a result, the selective formation of the first film on the first base is performed more precisely.

[0201] (e) By making the first film a film containing a metal element, the film formation process in step A and the etching process in step B can be performed precisely, respectively. As a result, the selective formation of the first film on the first base is performed more precisely.

[0202] By making the first film a film containing a metal element and O, the same effect can be obtained. In addition, the first film can be used as an oxidation high-k film having a large dielectric constant.

[0203] By making the first film a film containing a metal element and N, the same effect can be obtained. In addition, the first film can be used as a nitride high-k film having a large dielectric constant. In addition, by making the first film not contain oxygen, oxidation of the first base during step A can be avoided.

[0204] (f) By performing step C after step B, the second film having a different composition from the first film can be formed on the first film remaining on the first base.

[0205] (g) By performing step Cl in step C, in which the surface of the second base is modified to form a surface with the second end cap before the second film forming agent is supplied to the substrate, the selective formation of the second film on the first film remaining on the first base can be performed more precisely.

[0206] (h) By performing the cycle including steps C2 and C3 a prescribed number of times after step Cl in step C, the thickness of the second film formed in the recesses can be precisely controlled. As a result, the selective formation of the second film on the first film is performed more precisely.

[0207] (i) By forming a film containing a metal element and O as the first film in step A and forming a film containing a non-metal element and O as the second film in step C, a laminated structure of these films can be selectively formed on the first base.

[0208] The same effects can be obtained by forming a film containing a metal element and N as the first film in step A and forming a film containing a nonmetal element and O as the second film in step C. In addition, by not including oxygen in the first film to be formed in step A, oxidation of the first substrate can be prevented.

[0209] The same effects can be obtained by forming a film containing a metal element and N as the first film in step A and forming a film containing a nonmetal element and N as the second film in step C. In addition, by not including oxygen in the first film in step A, oxidation of the first substrate can be prevented, and by not including oxygen in the second film to be formed in step C, oxidation of the first film and the first substrate can be prevented.

[0210] (j) In the case where the second substrate is a film containing O, by performing step Al, the surface of the second substrate is easily modified to a surface on which the first capping is formed. Thus, the selective formation of the first film on the first substrate can be performed more precisely.

[0211] In addition, in the case where the second substrate is a film containing O, by performing step Cl, the surface of the second substrate is easily modified to a surface on which the second capping is formed. As a result, the selective formation of the second film on the first film remaining on the first substrate can be performed more precisely.

[0212] (k) For example, if the first film is used as a film constituting a charge trap layer of a memory cell, the performance of a flash memory device can be improved.

[0213] (l) By making the thickness of the first substrate thinner than the thickness of the first film on the first substrate after step B, in the case where the first film is used as a film constituting a charge trap layer of a memory cell, interference between adjacent charge trap layers can be reduced, and the performance of a flash memory device can be improved.

[0214] (m) In the case where a prescribed substance is selected from the above-described various modifiers, various film formers, various reactants, various etching agents, and various nonreactive gases and used, the above-described effects can also be obtained.

[0215] (4) Modified Examples

[0216] This embodiment mode can be modified as follows. In addition, the modified examples shown below can be arbitrarily combined.

[0217] (Modified Example 1)

[0218] After step C is performed, step D of supplying an oxidizing agent as a reactant (fourth reactant) to the substrate can be performed using the same processing steps as step A3.

[0219] As the processing conditions when the oxidizing agent is supplied in Step D, the following can be exemplified:

[0220] Processing temperature: 350 to 1000°C, preferably 400 to 650°C;

[0221] Processing pressure: 1 to 105000 Pa, preferably 10 to 10000 Pa;

[0222] Processing time: 1 to 10000 seconds, preferably 5 to 3600 seconds;

[0223] Oxidizing agent supply flow rate: 0.01 to 10 slm, preferably 0.1 to 5 slm;

[0224] Non-reactive gas supply flow rate (per gas supply pipe): 0 to 20 slm.

[0225] As the oxidizing agent, for example, ozone (O3), oxygen (O2) + hydrogen (H2), O2+ deuterium (D2), O3+ H2, O3+ D2, water vapor (H2O), hydrogen peroxide (H2O2), O2excited to a plasma state, O3, and the like, which are oxygen-containing substances having strong oxidizing power, can be used. As the oxidizing agent, one or more of these can be used. Here, the collective description of two substances such as "O2+ H2" means a mixture of O2and H2. In the case of supplying a mixture, the two substances can be mixed (pre-mixed) in the supply pipe and then supplied to the processing chamber 201, or the two substances can be supplied to the processing chamber 201 from different supply pipes and mixed (post-mixed) in the processing chamber 201.

[0226] In this modification, the same effects as the above-described mode can also be obtained.

[0227] In addition, in the case where a metal nitride film is formed as the first film in Step A, in this modification, by performing Step D, at least a part of the first film can be modified (changed) to an oxidized film such as a metal oxide film, a metal oxynitride film, and the like via the second film.

[0228] In addition, in the case where a metal oxide film is formed as the first film in Step A, in this modification, by performing Step D, at least a part of the first film can be modified (changed) to an oxidized film that is less impure and denser via the second film.

[0229] In addition, in this modification, by performing the modification (oxidation) of the first film via the second film, at least a part of the second film can be modified (changed) to an oxidized film that is less impure and denser.

[0230] (Modification 2)

[0231] In step C, an oxidant with strong oxidizing power can be used as the reactant (third reactant), such as O3, O2+H2, O2+D2, O3+H2, O3+D2, H2O2, or O2 and O3 excited into a plasma state. The processing conditions can be set to the same conditions as those in step D of Modified Example 1 when the oxidant is supplied.

[0232] In this variation, the same effect as described above can also be achieved.

[0233] Furthermore, in the case where a metal nitride film is formed as the first film in step A, in this modified example, by using an oxidant with strong oxidizing power to perform step C, it is possible to modify (change) at least a portion of the first film, which serves as its substrate, into an oxide film such as a metal oxide film or a metal oxynitride film when forming the second film.

[0234] Furthermore, in the case where a metal oxide film is formed as the first film in step A, in this modified example, by using an oxidant with strong oxidizing power to perform step C, at least a portion of the first film can be modified (changed) into a more dense oxide film with fewer impurities.

[0235] Furthermore, in this modified example, by using an oxidant with strong oxidizing power as the third reactant in step C, the second film can be made into a dense oxide film with few impurities.

[0236] (Variation Example 3)

[0237] After step B and before step C, step E can be performed by supplying the substrate with oxidants containing O and H, such as H2O and H2O2, as reactants (reactant #5) through the same processing steps and conditions as step A3.

[0238] In this variation, the same effect as described above can also be achieved.

[0239] Furthermore, in this modified example, by performing step E, which involves supplying an oxidant containing O and H to the substrate after step B and before step C, halogen elements (Cl, F, etc.) adsorbed and remaining on the surface of the second substrate due to step B can be removed, and the surface of the second substrate can be capped using OH groups. This allows for efficient selective capping of the second substrate in step C1.

[0240] (Variation Example 4)

[0241] In step B, the first film can be etched using an etchant alone without using the second reactant.

[0242] In addition, in this case, the etchant supply can be performed intermittently multiple times or continuously.

[0243] In these modification examples, the same effects as the above-described mode can be obtained.

[0244] <Other modes of the present disclosure>

[0245] The above describes the mode of the present disclosure in detail. However, the present disclosure is not limited to the above-described mode, and various modifications can be made within the scope of the gist thereof.

[0246] In the above-described mode, an example in which a metal oxide film, a metal nitride film is formed using a substance containing a metal element as the first film forming agent in step A is described. The present disclosure is not limited to the above-described mode, and for example, can be applied to a case in which an oxide film, a nitride film containing a nonmetal element, particularly, the above-described semimetal element is formed using a substance containing the element as the first film forming agent in step A. In addition, in the above-described mode, an example in which an oxide film, a nitride film containing a nonmetal element is formed using a substance containing the nonmetal element as the second film forming agent in step C is described. The present disclosure is not limited to the above-described mode, and for example, can be applied to a case in which an oxide film, a nitride film containing the above-described metal element is formed using a substance containing the metal element as the second film forming agent in step C.

[0247] It is preferable that the recipe used in each process is prepared separately in correspondence with the contents of the process, and recorded and stored in advance in the storage device 121c via the electric communication line, the external storage device 123. Also, it is preferable that the CPU 121a appropriately selects a suitable recipe from among the plurality of recipes recorded and stored in the storage device 121c in correspondence with the contents of the process at the start of each process. Thus, various kinds of films, composition ratios, film qualities, film thicknesses can be formed with good reproducibility by the processing device. Furthermore, each process can be started promptly while reducing the burden on the operator and avoiding operational errors.

[0248] The above-described recipe is not limited to a newly prepared one, and for example, can be prepared by modifying an existing recipe already installed in the processing device. In the case of modifying the recipe, the modified recipe can be installed in the processing device via the electric communication line, a recording medium on which the recipe is recorded. Furthermore, the existing recipe already installed in the processing device can be modified directly by operating the input / output device 122 provided in the existing processing device.

[0249] In the above-described mode, an example in which film formation processing is performed by a batch processing apparatus that processes a plurality of substrates at a time is described. The present disclosure is not limited to the above-described mode, and for example, in a case where film formation processing is performed by a single-wafer processing apparatus that processes one or a plurality of substrates at a time, the same can be appropriately applied. Further, in the above-described mode, an example in which film formation processing is performed by a processing apparatus having a processing furnace of a hot-wall type is described. The present disclosure is not limited to the above-described mode, and in a case where film formation processing is performed by a processing apparatus having a processing furnace of a cold-wall type, the same can be appropriately applied.

[0250] Further, in the above-described mode, an example in which a series of processing sequences of steps A to C are performed in-situ is described. The present disclosure is not limited to the above-described mode. As to any one of steps A to C and any other step, the processing can be performed in different processing chambers of different processing apparatuses (ex-situ), or can be performed in different processing chambers of the same processing apparatus, respectively.

[0251] In a case where these processing apparatuses are used, each processing can be performed by the same processing steps and processing conditions as those of the above-described mode and modified example, and the same effects as those of the above-described mode and modified example can be obtained.

[0252] The above-described mode and modified example can be used in combination as appropriate. The processing steps and processing conditions at this time can be set to be the same as those of the above-described mode and modified example, for example. [Patent Literature 1] Japanese Patent Application Publication No. 2016- 214 1

Claims

1. A substrate processing method, comprising: (a) a step of supplying a film forming agent to a substrate having a recessed portion with a bottom surface made of a first base and a side surface made of a second base on a surface, and forming a first film on the first base in a manner thicker than a thickness of the first film formed on the second base; and (b) a step of supplying an etching agent to the substrate, and removing the first film formed on the second base in a state where at least a part of the first film formed on the first base remains.

2. The substrate processing method as recited in claim 1, wherein, In the step (b), a cycle including the following steps is performed a prescribed number of times: (b1) a step of supplying the etching agent to the substrate; and (b2) a step of supplying a second reactant, which is a different substance from the etching agent and reacts with the first film, to the substrate.

3. The substrate processing method as recited in claim 1, wherein, In the step (a), before the step of supplying the film forming agent to the substrate, a step of: (a1) supplying a modifier to the substrate, and selectively modifying a surface of the second base to a first-terminated surface on which at least a part of the film forming agent is inhibited from being adsorbed, with respect to a surface of the first base.

4. The substrate processing method as recited in claim 3, wherein, In the step (a), after the step (a1), a cycle including the following steps is performed a prescribed number of times: (a2) a step of supplying the film forming agent to the substrate; and (a3) a step of supplying a first reactant to the substrate.

5. The substrate processing method as recited in claim 1, wherein, In the step (a), a film containing a metal element is formed as the first film.

6. The substrate processing method as recited in claim 1, wherein, In the step (a), a film containing a metal element and oxygen is formed as the first film.

7. The substrate processing method as recited in claim 1, wherein, In the step (a), a film containing a metal element and nitrogen is formed as the first film.

8. The substrate processing method as recited in claim 1, wherein, After the step (b), a step of: (c) supplying a second film forming agent to the substrate, and forming a second film different in composition from the first film on the first film is performed.

9. The substrate processing method as recited in claim 8, wherein, In the step (c), before the step of supplying the second film forming agent to the substrate, a step of: (c1) supplying a second modifier to the substrate, and selectively modifying a surface of the second base to a second-terminated surface on which at least a part of the second film forming agent is inhibited from being adsorbed, with respect to a surface of the first film is performed.

10. The substrate processing method as recited in claim 9, wherein, In the step (c), after the step (c1), a cycle including the following steps is performed a prescribed number of times: (c2) a step of supplying the second film forming agent to the substrate; and (c3) a step of supplying a third reactant to the substrate.

11. The substrate processing method as defined in any one of claims 8 to 10, wherein, In the step (a), a film containing a metal element and oxygen is formed as the first film, In the step (c), a film containing a non-metal element and oxygen is formed as the second film.

12. The substrate processing method as defined in any one of claims 8 to 10, wherein, In the step (a), a film containing a metal element and nitrogen is formed as the first film, In the step (c), a film containing a non-metal element and oxygen is formed as the second film.

13. The substrate processing method as defined in any one of claims 8 to 10, wherein, In the step (a), a film containing a metal element and nitrogen is formed as the first film, In the step (c), a film containing a non-metal element and nitrogen is formed as the second film.

14. The substrate processing method as recited in Claim 12, wherein, The second base is a film containing oxygen.

15. The substrate processing method as recited in Claim 12, wherein, After the step (c), a step of: (d) a step of supplying an oxidizing agent to the substrate, and modifying at least a part of the first film into an oxidized film via the second film.

16. The substrate processing method as set forth in claim 1, wherein, The first film is a film that constitutes at least a part of a charge trapping layer of a memory cell.

17. The substrate processing method as set forth in claim 1, wherein, The first substrate has a thickness that is thinner than a thickness of the first film on the first substrate after the (b).

18. A method for manufacturing a semiconductor device, comprising: (a) a step of supplying a film forming agent to a substrate having a recess with a bottom surface composed of a first substrate and a side surface composed of a second substrate on a surface, to form a first film on the first substrate in a manner that the first film has a thickness that is thicker than a thickness of a first film formed on the second substrate; and (b) a step of supplying an etching agent to the substrate, to remove the first film formed on the second substrate in a state that at least a part of the first film formed on the first substrate remains.

19. A program product that causes a substrate processing apparatus to execute the following steps using a computer: (a) a step of supplying a film forming agent to a substrate having a recess with a bottom surface composed of a first substrate and a side surface composed of a second substrate on a surface, to form a first film on the first substrate in a manner that the first film has a thickness that is thicker than a thickness of a first film formed on the second substrate; and (b) a step of supplying an etching agent to the substrate, to remove the first film formed on the second substrate in a state that at least a part of the first film formed on the first substrate remains.

20. A substrate processing apparatus, comprising: a film forming agent supply system that supplies a film forming agent to a substrate; an etching agent supply system that supplies an etching agent to a substrate; and a control section configured to control the film forming agent supply system and the etching agent supply system to perform (a) a process of supplying the film forming agent to a substrate having a recess with a bottom surface composed of a first substrate and a side surface composed of a second substrate on a surface, to form a first film on the first substrate in a manner that the first film has a thickness that is thicker than a thickness of a first film formed on the second substrate, and (b) a process of supplying the etching agent to the substrate, to remove the first film formed on the second substrate in a state that at least a part of the first film formed on the first substrate remains.

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