WO2018230377A1

WO2018230377A1 - Substrate processing method

Info

Publication number: WO2018230377A1
Application number: PCT/JP2018/021316
Authority: WO
Inventors: 勇志片桐; 昇岩本; 賢治関口
Original assignee: 東京エレクトロン株式会社
Priority date: 2017-06-14
Filing date: 2018-06-04
Publication date: 2018-12-20
Also published as: TW201921478A; JPWO2018230377A1

Abstract

Firstly, a substrate W having a recess pattern (25) that has a lateral wall (27) on which a metal part (23) is formed is prepared. Secondly, an oxide film (29) is formed by oxidizing a part of the metal part (23), which is formed on the lateral wall (27) of the recess pattern (25) in the substrate W, from the surface side. Subsequently, the oxide film (29) is selectively removed by supplying an etching liquid to the substrate W. In the step for forming the oxide film (29), a part of the metal part (23) is oxidized in a state where the metal part (23) is exposed to the atmosphere.

Description

Substrate processing method

The present disclosure relates to a substrate processing method.

2. Description of the Related Art Conventionally, a wet etching technique for etching a metal film formed on the surface of a substrate such as a semiconductor wafer (hereinafter referred to as a wafer) with an etchant is known as one of the processes when manufacturing a semiconductor device ( (See Patent Document 1)

JP 2013-033942 A

However, in a wafer having a concave pattern with a metal film formed on the surface, when an etching solution is used to etch the sidewall of the concave pattern by a desired amount, the etching speed differs between the upper part and the lower part of the concave pattern, There is a problem that etching cannot be performed uniformly at the bottom.

This is considered to be because the substituting property of the etching solution existing in the concave pattern becomes non-uniform in the concave pattern. That is, in the upper part in the concave pattern, the reactive species contributing to the etching contained in the etching solution are always replaced with new reactive species, and therefore the concentration of the reactive species is relatively high. On the other hand, in the lower part in the concave pattern, the etching solution tends to stay, so that the reactive species are not easily replaced, and the concentration of the reactive species is relatively low. Thus, it is considered that the concentration of the etching solution is different between the upper part and the lower part of the concave pattern, so that the concentration gradient of the reactive species is generated between the upper part and the lower part of the concave pattern, and the etching amount is different.

The present disclosure has been made in consideration of such points, and provides a substrate processing method capable of making the etching amount uniform between the upper part and the lower part in the concave pattern of the substrate.

According to one aspect of the present disclosure, a step of preparing a substrate having a concave pattern having a side wall on which a metal part is formed, and a part of the metal part formed on the side wall of the concave pattern of the substrate from the surface side A first step of forming an oxide film by oxidizing, and a second step of selectively removing the oxide film by supplying an etching solution to the substrate. In the first step, the metal The present invention relates to a substrate processing method in which a part of the metal part is oxidized while the part is exposed to the atmosphere.

According to the present disclosure, the etching amount can be made uniform between the upper part and the lower part in the concave pattern of the substrate.

FIG. 1 is a plan view illustrating a schematic configuration of a substrate processing system (substrate processing apparatus) according to an embodiment. FIG. 2 is a side sectional view showing a schematic configuration of the processing unit shown in FIG. FIG. 3 is a diagram illustrating a schematic configuration of a processing fluid supply unit of the processing unit. FIG. 4 is a diagram illustrating a schematic configuration of the heat treatment unit. FIGS. 5A to 5D are schematic cross-sectional views showing the wafer being processed. FIG. 6 is a flowchart showing a substrate processing method according to an embodiment. 7A and 7B are schematic cross-sectional views showing modifications of the wafer.

Hereinafter, an embodiment will be described with reference to the drawings. In addition, the structure shown in drawing attached to this specification may contain the part from which size and the scale etc. were changed from those of the real thing for convenience of illustration and an understanding.

FIG. 1 is a diagram showing a schematic configuration of a substrate processing system according to the present embodiment. In the following, in order to clarify the positional relationship, the X axis, the Y axis, and the Z axis that are orthogonal to each other are defined, and the positive direction of the Z axis is the vertically upward direction.

As shown in FIG. 1, the substrate processing system 1 includes a carry-in / out station 2 and a processing station 3. The carry-in / out station 2 and the processing station 3 are provided adjacent to each other.

The loading / unloading station 2 includes a carrier placement unit 11 and a conveyance unit 12. A plurality of carriers C that accommodate a plurality of wafers W in a horizontal state are placed on the carrier placement unit 11.

The transfer unit 12 is provided adjacent to the carrier placement unit 11 and includes a substrate transfer device 13 and a delivery unit 14 inside. The substrate transfer device 13 includes a substrate holding mechanism that holds the wafer W. Further, the substrate transfer device 13 can move in the horizontal direction and the vertical direction and turn around the vertical axis, and transfers the wafer W between the carrier C and the delivery unit 14 using the substrate holding mechanism. Do.

The processing station 3 is provided adjacent to the transfer unit 12. The processing station 3 includes a transport unit 15 and a plurality of processing units 16. The plurality of processing units 16 are provided side by side on the transport unit 15.

The transfer unit 15 includes a substrate transfer device 17 inside. The substrate transfer device 17 includes a substrate holding mechanism that holds the wafer W. Further, the substrate transfer device 17 can move in the horizontal direction and the vertical direction and can turn around the vertical axis, and transfers the wafer W between the delivery unit 14 and the processing unit 16 using the substrate holding mechanism. I do.

The processing unit 16 performs predetermined substrate processing on the wafer W transferred by the substrate transfer device 17.

Further, the substrate processing system 1 includes a control device 4. The control device 4 is a computer, for example, and includes a control unit 18 and a storage unit 19. The storage unit 19 stores a program for controlling various processes executed in the substrate processing system 1. The control unit 18 controls the operation of the substrate processing system 1 by reading and executing the program stored in the storage unit 19.

Note that such a program may be recorded in a computer-readable storage medium and installed in the storage unit 19 of the control device 4 from the storage medium. Examples of the computer-readable storage medium include a hard disk (HD), a flexible disk (FD), a compact disk (CD), a magnetic optical disk (MO), and a memory card.

In the substrate processing system 1 configured as described above, first, the substrate transfer device 13 of the loading / unloading station 2 takes out the wafer W from the carrier C placed on the carrier placement unit 11 and receives the taken-out wafer W. Place on the transfer section 14. The wafer W placed on the delivery unit 14 is taken out from the delivery unit 14 by the substrate transfer device 17 of the processing station 3 and carried into the processing unit 16.

The wafer W loaded into the processing unit 16 is processed by the processing unit 16, then unloaded from the processing unit 16 by the substrate transfer device 17, and placed on the delivery unit 14.
Then, the processed wafer W placed on the delivery unit 14 is returned to the carrier C of the carrier platform 11 by the substrate transfer device 13.

By the way, in the present embodiment, a heating unit 16 </ b> A for heating the wafer W is provided in the processing station 3 adjacent to the plurality of processing units 16. In FIG. 1, two heating units 16A are shown for convenience, but the number of heating units 16A can be any number.

[Processing unit]
Next, a schematic configuration of the processing unit 16 will be described with reference to FIG. FIG. 2 is a diagram showing a schematic configuration of the processing unit 16.

As shown in FIG. 2, the processing unit 16 includes a chamber 20, a substrate holding mechanism 30, a processing fluid supply unit 40, and a recovery cup 50.

The chamber 20 accommodates the substrate holding mechanism 30, the processing fluid supply unit 40, and the recovery cup 50. An FFU (Fan Filter Unit) 21 is provided on the ceiling of the chamber 20. The FFU 21 forms a down flow in the chamber 20.

The substrate holding mechanism 30 includes a holding part 31, a support part 32, and a driving part 33. The holding unit 31 holds the wafer W horizontally. The support | pillar part 32 is a member extended in a perpendicular direction, a base end part is rotatably supported by the drive part 33, and supports the holding | maintenance part 31 horizontally in a front-end | tip part. The drive unit 33 rotates the column unit 32 around the vertical axis. The substrate holding mechanism 30 rotates the support unit 32 by rotating the support unit 32 using the drive unit 33, thereby rotating the wafer W held by the support unit 31. .

The processing fluid supply unit 40 supplies a processing fluid to the wafer W. The processing fluid supply unit 40 is connected to a processing fluid supply source 70.

The recovery cup 50 is disposed so as to surround the holding unit 31, and collects the processing liquid scattered from the wafer W by the rotation of the holding unit 31. A drain port 51 is formed at the bottom of the recovery cup 50, and the processing liquid collected by the recovery cup 50 is discharged from the drain port 51 to the outside of the processing unit 16. Further, an exhaust port 52 for discharging the gas supplied from the FFU 21 to the outside of the processing unit 16 is formed at the bottom of the recovery cup 50.

In this embodiment, the processing fluid supply unit 40 includes an arm 45 and a chemical nozzle 41 and a rinse nozzle 42 provided on the arm 45 (see FIG. 3).

Of these, the chemical nozzle 41 is a nozzle that discharges a chemical (etching liquid) for etching such as DHF (dilute hydrofluoric acid). The rinse nozzle 42 is a nozzle that discharges a rinse liquid such as DIW (pure water).

[Heating unit]
Next, a schematic configuration of the heating unit 16A will be described with reference to FIG. FIG. 4 is a diagram showing a schematic configuration of the heating unit 16A.

As shown in FIG. 4, the heating unit 16 </ b> A is provided in the processing container 53, the table 54 disposed in the processing container 53, on which the wafer W to be processed is placed, and placed on the table 54. And a heating part (heater) 55 such as a heating wire for heating the wafer W.

An oxygen concentration adjusting unit 56 and a humidity adjusting unit 57 are connected to the processing container 53. Among these, the oxygen concentration adjusting unit 56 supplies, for example, oxygen and nitrogen into the processing container 53.
The oxygen concentration in the processing vessel 53 can be adjusted by appropriately adjusting the amount of oxygen and the amount of nitrogen supplied from the oxygen concentration adjusting unit 56 into the processing vessel 53.

Further, the humidity adjusting unit 57 supplies, for example, steam and dry air into the processing container 53. The humidity in the processing container 53 can be adjusted by appropriately adjusting the amount of steam and the amount of dry air supplied from the humidity adjusting unit 57 into the processing container 53.

The heating unit 16A may be a unit that heats the wafer W by a heating unit such as an LED lamp instead of the heating unit (heater) 55 such as a heating wire.

[Substrate processing method]
Next, the substrate processing method according to the present embodiment will be described with reference to FIGS.

[Board preparation]
First, a wafer W having a concave pattern 25 is prepared (step S1 in FIG. 6). As shown in FIG. 5A, the wafer W has a concave pattern 25 formed in an uneven shape. The concave pattern 25 has a bottom surface 26, a side wall 27 extending perpendicularly from the bottom surface 26, and an upper surface 28 formed on the side wall 27. Further, the wafer W includes a main body portion 24 made of a material such as SiO or SiN, and a metal film (metal portion) 23 formed on the main body portion 24.

The metal film 23 is formed on the bottom surface 26, the side wall 27, and the top surface 28 of the concave pattern 25 with a substantially uniform thickness. In this case, the thickness t ₁ of the metal film 23 is, for example, 1 nm to 10 nm. Further, as the metal film 23, a material containing at least one of Ti, Cu, and Co is used. In the present embodiment, the case where the material of the metal film 23 is TiN will be described as an example.

[Oxidation of metal film]
Next, the wafer W is carried into the heating unit 16 </ b> A (see FIG. 4) by the substrate transfer device 17 and placed on the table 54 provided in the processing container 53. Subsequently, the wafer W is heated from the lower surface side thereof by the heating unit 55 (first step, step S2 in FIG. 6). At this time, the wafer W is in an air atmosphere in the processing container 53 and is heated in a state where the metal film 23 is exposed to the air.

While the wafer W is heated, the metal film 23 is exposed to the atmosphere, so that the metal film 23 is oxidized by reacting with oxygen in the atmosphere. Thereby, a part of the thickness direction of the metal film 23 is oxidized from the surface side (side exposed to the atmosphere) to form an oxide film 29 (FIG. 5B). For example, when the metal film 23 is TiN, an oxide film 29 made of TiO ₂ is formed on a part of the metal film 23 (see FIG. 5B).

When the wafer W is heated in this way, the metal film 23 is heated substantially uniformly on the bottom surface 26 side and the top surface 28 side of the concave pattern 25. For this reason, the temperature of the metal film 23 during heating is substantially uniform between the bottom surface 26, the sidewall 27, and the top surface 28, and as a result, the oxidation of the metal film 23 is also approximately mutually performed between the bottom surface 26, the sidewall 27, and the top surface 28. It is thought that it progresses uniformly. Therefore, the thickness t ₂ of the oxide film 29 is substantially uniform between the bottom surface 26, the side wall 27, and the upper surface 28, and the thickness t ₂ of the oxide film 29 is equal to the upper portion (on the upper surface 28 side) and the lower portion (bottom surface) 26 side) is substantially uniform. Specifically, the thickness _{t 2} of the oxide film 29 is, for example, 0.5 nm ~ 5 nm.

While the wafer W is heated in this manner, the atmosphere in the processing container 53 is controlled by the oxygen concentration adjusting unit 56 so that the oxygen concentration in the processing container 53 is adjusted to a predetermined value. Specifically, the oxygen concentration adjusting unit 56 increases and decreases the oxygen concentration in the processing container 53 by supplying oxygen and nitrogen into the processing container 53, respectively. The oxygen concentration in the processing container 53 is, for example, 10% to 30%, preferably 18% to 25%.

Further, the atmosphere in the processing container 53 is controlled by the humidity adjusting unit 57 so that the humidity in the processing container 53 becomes a predetermined value. Specifically, the humidity adjusting unit 57 raises and lowers the humidity in the processing container 53 by supplying steam and dry air into the processing container 53, respectively.

The temperature at which the wafer W is heated by the heating unit 55 is, for example, 250 ° C. to 350 ° C., and preferably 280 ° C. to 320 ° C. Further, the time for heating the wafer W is, for example, 1 minute to 10 minutes, and preferably 2 minutes to 4 minutes.

Thus, by controlling the formation conditions of the oxide film 29, the degree of progress of the oxidation of the metal film 23 can be adjusted, thereby controlling the thickness t ₂ (etching amount described later) of the oxide film 29. be able to. The formation conditions of the oxide film 29 include the oxygen concentration in the atmosphere when the wafer W is heated, the humidity in the atmosphere, the heating time (processing time) of the wafer W, and the heating time (processing time) of the wafer W. Of these, one or more may be mentioned.

The formation conditions of the thickness t ₂ and the oxide film 29 of the oxide film 29 and are associated in advance, for example, the storage unit 19 of the control device 4 may be stored (see FIG. 1). In this case, by inputting the necessary thickness t ₂ (etching amount) of the oxide film 29 to the control device 4, the control device 4 automatically obtains the formation condition of the oxide film 29 corresponding to the thickness t _2. . Then, the control device 4 may control the heating unit 16 </ b> A so as to form the oxide film 29 based on the obtained formation condition of the oxide film 29.

Thereafter, the wafer W on which the oxide film 29 is formed is unloaded from the heating unit 16A by the substrate transfer device 17.

[Substrate loading]
Next, the wafer W unloaded from the heating unit 16A is loaded into the processing unit 16 (see FIG. 2) by the substrate transfer device 17 and held by the substrate holding mechanism 30 (step S3 in FIG. 6). Next, the wafer W starts to rotate by operating the driving unit 33. The wafer W continues to rotate until the drying process described later is completed.

[Etching process]
Next, when the arm 45 is driven, the chemical nozzle 41 is positioned directly above the center of the wafer W, and an etching chemical such as DHF is supplied from the chemical nozzle 41 to the center of the surface of the wafer W over a predetermined time. (Second step, step S4 in FIG. 6). The supplied chemical solution spreads by centrifugal force and flows toward the outside of the wafer W. At this time, the entire surface of the wafer W is covered with a chemical liquid film. Specifically, the oxide film 29 formed on the wafer W is covered with the chemical solution L (see FIG. 5C).

In this way, by supplying the chemical solution to the surface of the wafer W, the oxide film 29 formed on the wafer W is selectively removed. That is, the oxide film 29 made of TiO ₂ is entirely removed by an etching chemical such as DHF, while the metal film 23 made of TiN that hardly reacts with the chemical remains without being removed (FIG. 5 ( d)).

As described above, the thickness t ₂ of the oxide film 29 is substantially uniform between the bottom surface 26, the side wall 27, and the top surface 28, and is also substantially uniform between the upper portion and the lower portion of the side wall 27. Therefore, the etching amount (that is, the thickness t ₂ of the oxide film 29) that is the thickness of the original metal film 23 removed by etching can be made substantially uniform between the upper part and the lower part of the side wall 27.

[Rinse processing]
Subsequently, the supply of the chemical solution is stopped, and the rinse nozzle 42 is positioned right above the center portion of the wafer W, and a rinse solution such as DIW is supplied from the rinse nozzle 42 to the center portion of the surface of the wafer W over a predetermined time. (Step S5 in FIG. 6). The supplied rinse liquid spreads by centrifugal force and flows toward the outside of the wafer W. At this time, the entire surface of the wafer W is covered with the liquid film of the rinse liquid. As a result, the chemical solution (DHF) remaining on the surface of the wafer W and the reaction product during the chemical treatment are washed away by the rinse liquid and removed from the surface of the wafer W. Thereafter, the supply of the rinse liquid is stopped.

[Drying process]
When the rinsing process is completed, the drying process is executed (step S6 in FIG. 6). That is, the discharge of the rinse liquid from the rinse nozzle 42 is stopped, the number of rotations of the wafer W is increased, and the wafer W is shaken and dried.

When the drying process is completed, the rotation of the wafer W is stopped. As a result, a series of processing for the wafer W is completed. Thereafter, the wafer W is unloaded from the processing unit 16 by the substrate transfer device 17.

As described above, according to the present embodiment, a part of the metal film 23 formed on the side wall 27 of the concave pattern 25 of the wafer W is oxidized from the surface side in a state where the metal film 23 is exposed to the atmosphere. Then, an oxide film 29 is formed (first step). Thereafter, the oxide film 29 is selectively removed by supplying an etching chemical to the wafer W (second step). As described above, the step (first step) of oxidizing the metal film 23 formed on the concave pattern 25 is provided before the step of supplying the etching chemical (second step). Thereby, the oxide film 29 can be formed with a substantially uniform thickness with respect to the metal film 23 between the upper part and the lower part of the side wall 27. Therefore, by selectively removing the oxide film 29 with a chemical solution for etching, the upper and lower portions of the metal film 23 can be etched uniformly. That is, the etching amount can be made uniform between the upper part and the lower part in the concave pattern 25 of the wafer W.

Further, according to the present embodiment, when the oxide film 29 is formed, a part of the metal film 23 is oxidized by heating the wafer W. When the wafer W is heated, the metal film 23 can be heated substantially uniformly at the upper and lower portions in the concave pattern 25 of the wafer W, so that it is substantially uniform between the upper and lower portions of the side wall 27 of the metal film 23. An oxide film 29 can be formed to a thickness.

Further, according to the present embodiment, at least one of the thickness of the oxide film 29 and the formation conditions of the oxide film 29 (for example, the oxygen concentration in the atmosphere, the humidity in the atmosphere, the processing temperature of the wafer W, and the processing time of the wafer W). Are associated in advance. In this case, in the step of oxidizing the metal film 23 (first step), the oxide film 29 is formed based on the formation conditions of the oxide film 29. Thus, the metal film 23 can be etched by a desired etching amount by appropriately adjusting the formation conditions of the oxide film 29.

In the case where the metal film 23 is directly etched with a chemical solution such as SC2 (hydrochloric acid / hydrogen peroxide / water mixture) without forming the oxide film 29 (without passing through the first step), The contained reactive species tend to stay in the lower part of the concave pattern 25. For this reason, it is difficult for the reactive species to be interchanged between the upper portion and the lower portion of the concave pattern 25, and the concentration of the reactive species tends to be low at the lower portion of the concave pattern 25. In this case, a concentration gradient of the reactive species is generated between the upper part and the lower part of the concave pattern 25, and there is a possibility that a difference in etching amount occurs. On the other hand, instead of etching the metal film 23 at once, it is also conceivable to repeat the etching process and the rinsing process for the metal film 23 a plurality of times until a desired etching amount is obtained. In this case, the replaceability of the etching solution can be improved between the upper part and the lower part of the concave pattern 25, and the etching amount can be made uniform between the upper part and the lower part of the concave pattern 25.

[Modification]
Next, a modification of this embodiment will be described.

In the above embodiment, the oxide film 29 is selectively formed by supplying a chemical solution for etching to the wafer W in the first step of forming the oxide film 29 by oxidizing a part of the metal film 23 of the wafer W. The case where the second step to be removed is performed once is described as an example. However, the present invention is not limited to this, and the first step and the second step may be repeated a plurality of times. Specifically, a step of forming the oxide film 29 on a part of the metal film 23 (first step, step S2 in FIG. 6) and a step of selectively removing the oxide film 29 formed on the wafer W (first step). Two steps, step S4 in FIG. 6, the step of rinsing the wafer W (step S5 in FIG. 6), and the step of drying the wafer W (step S6 in FIG. 6) are repeated a plurality of times in this order. It may be. Thereby, for example, even when the etching amount is large, that is, when the metal film 23 is deeply etched, the etching amount can be made uniform between the upper part and the lower part in the concave pattern 25 of the wafer W.

Moreover, in the said embodiment, the case where the oxide film 29 was formed in the metal film 23 by heating the wafer W within the heating unit 16A was demonstrated as an example (1st process). However, the present invention is not limited to this, and part of the metal film 23 may be oxidized by irradiating the wafer W with an electron beam such as ultraviolet rays. For example, ozone may be generated from oxygen in the atmosphere by irradiating the wafer W with ultraviolet rays from an LED lamp, and the oxide film 29 may be formed by oxidizing a part of the metal film 23 with the ozone. In this case, since the ultraviolet rays are evenly irradiated between the upper part and the lower part of the side wall 27 of the metal film 23, the oxide film 29 can be formed with a substantially uniform thickness between the upper part and the lower part of the side wall 27. it can. Thereby, the etching can be performed uniformly on the upper and lower portions of the metal film 23, and the etching amount can be made uniform. Also in this case, by controlling various formation conditions of the oxide film 29, the progress of the oxidation of the metal film 23 can be adjusted, and the etching amount for etching the metal film 23 can be controlled.
Such an oxide film 29 is formed by forming one or more of oxygen concentration in the atmosphere, humidity in the atmosphere, electron beam irradiation amount on the wafer W, and electron beam irradiation time (processing time) on the wafer W. Conditions can be mentioned.

In the above embodiment, the case where the metal film 23 is formed from the upper end to the lower end of the side wall 27 of the wafer W has been described as an example (see FIG. 5A). However, the present invention is not limited to this, and the metal portion to be etched may be formed only on a part of the side wall 27. For example, as illustrated in FIG. 7A, the insulating layers 34 and the metal layers (metal portions) 35 may be alternately formed along the height direction of the concave pattern 25 of the wafer W. Also in this case, a part of the metal layer 35 formed on the side wall 27 of the concave pattern 25 is oxidized to form the oxide film 29, and then the oxide film 29 can be selectively removed. Accordingly, as shown in FIG. 7B, etching can be performed substantially uniformly between the upper portion and the lower portion of the side wall 27. Specifically, the etching amount can be made uniform between the plurality of metal layers 35 arranged at the upper part and the lower part.

The present disclosure is not limited to the above-described embodiments and modifications, and may include various aspects to which various modifications that can be conceived by those skilled in the art are added, and the effects achieved by the present disclosure are also described above. It is not limited to the matter of. Therefore, various additions, modifications, and partial deletions can be made to each element described in the claims and the specification without departing from the technical idea and spirit of the present disclosure.

Claims

Preparing a substrate having a concave pattern having a sidewall on which a metal portion is formed;
A first step of forming an oxide film by oxidizing a part of the metal part formed on the side wall of the concave pattern of the substrate from the surface side;
A second step of selectively removing the oxide film by supplying an etchant to the substrate;
In the first step, a part of the metal part is oxidized in a state where the metal part is exposed to the atmosphere.
The substrate processing method according to claim 1, wherein the first step is a step of oxidizing a part of the metal part by heating the substrate.
The substrate processing method according to claim 1, wherein the first step is a step of oxidizing a part of the metal part by irradiating the substrate with an electron beam.
The thickness of the oxide film and the formation condition of the oxide film in the first step are associated in advance, and the oxide film is formed based on the formation condition of the oxide film in the first step. The substrate processing method according to any one of claims 1 to 3.
5. The substrate processing method according to claim 4, wherein the formation condition of the oxide film includes at least one of the oxygen concentration in the atmosphere, the humidity in the atmosphere, the processing temperature of the substrate, and the processing time of the substrate.
The substrate processing method according to any one of claims 1 to 5, wherein the metal part includes at least one of Ti, Cu, and Co.
The substrate processing method according to any one of claims 1 to 6, wherein the first step and the second step are repeated a plurality of times.