阅读说明：本技术 衬底处理方法 (Substrate processing method ) 是由 山口贵大 新庄淳一 中野佑太 泽崎尚树 阿野诚士 岩崎晃久 于 2020-02-04 设计创作，主要内容包括：本发明的目的在于提供衬底处理方法,其解决了若欲仅依赖臭氧的分解作用来除去阻剂膜,则处理时间变长的课题；虽然利用使阻剂膜溶胀而促进剥离,但在溶胀进行的程度上还存在较大改善的余地的课题,能够抑制废液处理的负担,并且能够在短时间内从衬底除去阻剂膜。衬底处理方法,其具备：使含臭氧水溶液(920)与衬底(901)上的阻剂膜接触的工序；以及使与含臭氧水溶液(920)相比以高浓度含有氨的含氨水溶液(930)与阻剂膜中的、已经与含臭氧水溶液(920)相接触的部分(P1)接触的工序。(The invention aims to provide a substrate processing method, which solves the problem that the processing time is long if only ozone decomposition action is relied on to remove a resistance agent film; although the peeling is promoted by swelling the resist film, there is a problem that the degree of progress of swelling is still a large margin for improvement, and the resist film can be removed from the substrate in a short time while suppressing the burden of waste liquid treatment. A substrate processing method includes: a step of bringing an aqueous solution (920) containing ozone into contact with the resist film on the substrate (901); and a step in which an ammonia-containing aqueous solution (930) containing ammonia at a higher concentration than the ozone-containing aqueous solution (920) is brought into contact with a portion (P1) of the resist film that has been brought into contact with the ozone-containing aqueous solution (920).)

1. A substrate processing method includes:

a step of bringing an ozone-containing aqueous solution into contact with the resist film on the substrate; and

a step of bringing an ammonia-containing aqueous solution into contact with a portion of the resist film that has been brought into contact with the ozone-containing aqueous solution by the step of contacting the ozone-containing aqueous solution, the ammonia-containing aqueous solution being an aqueous solution containing ammonia at a higher concentration than the ozone-containing aqueous solution.

2. The substrate processing method according to claim 1, wherein the step of contacting the ozone-containing aqueous solution is performed by discharging the ozone-containing aqueous solution to the substrate.

3. The substrate processing method according to claim 1 or 2, wherein the step of contacting the ammonia-containing aqueous solution is performed by ejecting an ammonia-containing aqueous solution to the substrate.

4. The substrate processing method according to claim 3, wherein the step of ejecting the aqueous ammonia-containing solution comprises a step of moving a nozzle that ejects the aqueous ammonia-containing solution.

5. The substrate processing method according to claim 4, wherein the step of moving the nozzle is performed so that an ammonia-containing aqueous solution is ejected to a peripheral portion of the substrate for a longer time than to a central portion of the substrate.

6. The substrate processing method of any of claims 1 to 5, further comprising: a step of separating, by physical cleaning, a portion of the resist film, which has been brought into contact with the aqueous solution containing ammonia by the step of contacting the aqueous solution containing ammonia, from the substrate.

7. The substrate processing method according to claim 6, wherein said physical cleaning comprises a step of blowing a gas to said substrate.

8. The substrate processing method according to claim 7, wherein the step of blowing a gas to the substrate comprises: and spraying an ammonia-containing aqueous solution onto the substrate with the gas.

9. The substrate processing method according to claim 7 or 8, wherein the gas is an inactive gas.

10. The substrate processing method according to any one of claims 1 to 5, wherein the step of contacting the ozone-containing aqueous solution comprises: and forming a crack in the resist film by using the ozone-containing aqueous solution.

11. The substrate processing method of claim 10, wherein the step of contacting the aqueous ammonia-containing solution comprises: and a step of allowing an aqueous solution containing ammonia to permeate into an interface between the substrate and the resist film through cracks formed in the resist film, thereby peeling the resist film from the substrate.

12. The substrate processing method of any of claims 1 to 11, wherein the aqueous ammonia-containing solution contains hydrogen peroxide.

13. The substrate processing method of any of claims 1 to 12, further comprising: and a step of irradiating the resist film with ultraviolet light before the step of contacting the aqueous solution containing ozone.

14. The substrate processing method according to any one of claims 1 to 13, wherein the step of contacting the ozone-containing aqueous solution comprises: and supplying an ozone-containing aqueous solution to the substrate without supplying an ammonia-containing aqueous solution to the substrate.

15. The substrate processing method of any of claims 1 to 14, wherein the step of contacting the ozone-containing aqueous solution comprises: and heating the ozone-containing aqueous solution in a pipe distant from the substrate.

16. The substrate processing method of any of claims 1 to 15, wherein the step of contacting the ozone-containing aqueous solution comprises: and heating the aqueous solution containing ozone on the substrate.

Technical Field

The present invention relates to a substrate processing method, and more particularly, to a substrate processing method for removing a resist film from a substrate.

Background

After processing using a resist film on a substrate, the resist film is often removed from the substrate. For the purpose of this treatment, conventionally, a method of supplying a sulfuric acid/hydrogen peroxide solution/mixed Solution (SPM) as a cleaning solution onto the surface of the substrate has been widely used. However, in recent years, a substrate processing method not using SPM has been demanded for reasons such as a large burden of waste liquid processing.

Japanese patent application laid-open No. 2010-153442 (patent document 1) discloses a substrate processing method for removing a resist film on a wafer. As an example, it is described that a resist film is removed by supplying a mixed liquid of ammonia water and ozone water to a wafer. According to this publication, it is claimed that the resist can be removed at a high rate.

Jp 2001-144006 a (patent document 2) proposes etching a resist film formed on a semiconductor wafer by supplying ozone-dissolved water and an ozone decomposition catalyst liquid onto the resist film. As a method shown in an appropriate example, first, ammonia water as an ozone decomposition catalyst liquid is sprayed onto a wafer. Then, ozone-dissolved water is sprayed onto the wafer. Thereby, ozone-dissolved water is sprayed onto the wafer surface in a state where the entire wafer surface is covered with the ozone decomposition catalyst liquid. According to this publication, it is claimed that the etching time can be shortened because ozone can be instantaneously decomposed on the wafer surface.

Japanese patent application laid-open No. 2001-203182 (patent document 3) discloses a method for cleaning the surface of an article. Specifically, an aqueous base solution and an aqueous ozone solution are simultaneously supplied to the surface of the article having a surface contaminated with the adherent. At this time, the surface is set to be continuously in contact with fresh aqueous alkali solution and aqueous ozone solution. Thereby, ozone is decomposed at the surface. Thereby, the adhering matter is removed. According to this publication, it is claimed that excellent cleaning effects can be obtained without using a special physical action (for example, high-pressure ejection jet) that may damage the surface of the article.

Japanese patent laying-open No. 4-179225 (patent document 4) discloses a cleaning method. This publication describes the following: as one embodiment of the cleaning method, an object to be cleaned is immersed in a cleaning liquid containing ammonia or amines, and hydrogen peroxide and/or ozone, and irradiated with ultraviolet rays. According to this publication, it is claimed that a heating facility or the like for the chemical solution is not required as an effect.

Japanese patent laid-open publication No. 2003-234323 (patent document 5) proposes a substrate processing method for removing an organic material. The organic substance is a reaction product formed on the surface of the substrate by dry etching using a resist as a mask. According to this substrate processing method, the organic substance is swelled by supplying the removing liquid to the surface of the substrate. Next, the substrate is rotated, thereby removing the removing liquid adhering to the substrate. Next, as described above, the residue of the swollen organic matter is peeled off. The peeling is performed by supplying a cleaning medium to the surface of the substrate. Examples of the removing liquid include a liquid containing an organic alkali solution. Examples of the cleaning medium include warm water. The reason why the removing liquid adhering to the substrate is removed before the cleaning medium is supplied is described as follows: the phenomenon that a strong base is generated due to the mixing of the two is avoided, so that the treatment for removing the strong base is not required to take time.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2010-153442

Patent document 2: japanese patent laid-open No. 2001-144006

Patent document 3: japanese laid-open patent application No. 2001-203182

Patent document 4: japanese laid-open patent publication No. 4-179225

Patent document 5: japanese patent laid-open publication No. 2003-234323

Disclosure of Invention

Problems to be solved by the invention

The techniques of patent documents 1 to 3 are intended to accelerate the decomposition of the resist film by promoting the action of ozone. According to the studies of the inventors of the present application, when it is intended to remove the resist film mainly relying only on the decomposition action, the treatment time becomes long.

The technique of patent document 4 is intended to remove a resist and the like by irradiating ultraviolet rays in a mixed liquid of several chemical solutions. Since the functions of the respective chemical solutions are gradually inactivated after mixing, the technique is likely to prevent the functions of the respective chemical solutions from being sufficiently exhibited. Therefore, the required processing time tends to be long.

According to the technique of patent document 5, peeling is promoted by swelling the resist film. However, according to the studies of the inventors of the present application, there is still room for a great improvement in the degree of progress of swelling. Therefore, there is room for improvement in reduction of the processing time.

The present invention has been made to solve the above-described problems, and an object thereof is to provide a substrate processing method capable of removing a resist film from a substrate in a short time while suppressing the burden of waste liquid processing.

Means for solving the problems

To solve the above problems, the 1 st aspect is a substrate processing method including: a step of bringing an ozone-containing aqueous solution into contact with the resist film on the substrate; and a step of bringing an ammonia-containing aqueous solution into contact with a portion of the resist film which has been brought into contact with the ozone-containing aqueous solution by the step of bringing the ozone-containing aqueous solution into contact, the ammonia-containing aqueous solution being an aqueous solution containing ammonia at a higher concentration than the ozone-containing aqueous solution.

The 2 nd aspect is the substrate processing method according to the 1 st aspect, wherein the step of contacting the ozone-containing aqueous solution is performed by discharging the ozone-containing aqueous solution to the substrate.

The 3 rd aspect is the substrate processing method according to the 1 st or 2 nd aspect, wherein the step of contacting the ammonia-containing aqueous solution is performed by ejecting the ammonia-containing aqueous solution to the substrate.

A 4 th aspect is the substrate processing method according to the 3 rd aspect, wherein the step of ejecting the aqueous ammonia-containing solution includes a step of moving a nozzle that ejects the aqueous ammonia-containing solution.

A 5 th aspect is the substrate processing method according to the 4 th aspect, wherein the step of moving the nozzle is performed so that the time for ejecting the aqueous ammonia-containing solution to the peripheral portion of the substrate is longer than that to the central portion of the substrate.

Mode 6 is the substrate processing method according to any one of modes 1 to 5, further comprising: and a step of separating, by physical cleaning, a portion of the resist film which has been brought into contact with the aqueous solution containing ammonia by the step of bringing the film into contact with the aqueous solution containing ammonia from the substrate.

A 7 th aspect is the substrate processing method according to the 6 th aspect, wherein the physical cleaning includes a step of blowing a gas onto the substrate.

An 8 th aspect is the substrate processing method according to the 7 th aspect, wherein the step of blowing a gas onto the substrate includes: and spraying an aqueous solution containing ammonia onto the substrate by using the gas.

A 9 th aspect is the substrate processing method according to the 7 th or 8, wherein the gas is an inert gas.

A 10 th aspect is the substrate processing method according to any one of the 1 st to 5, wherein the step of contacting the aqueous solution containing ozone includes: and forming cracks in the resist film by using the aqueous solution containing ozone.

An 11 th aspect is the substrate processing method according to the 10 th aspect, wherein the step of contacting the ammonia-containing aqueous solution includes: and a step of separating the resist film from the substrate by allowing an aqueous solution containing ammonia to permeate into an interface between the substrate and the resist film through a crack formed in the step of forming a crack in the resist film.

A 12 th aspect is the substrate processing method according to any one of the 1 st to 11 th aspects, wherein the ammonia-containing aqueous solution contains hydrogen peroxide.

Mode 13 is the substrate processing method according to any one of modes 1 to 12, further comprising: and a step of irradiating the resist film with ultraviolet light before the step of contacting the aqueous solution containing ozone.

A 14 th aspect is the substrate processing method according to any one of the 1 st to 13, wherein the step of contacting the aqueous solution containing ozone includes: and supplying an ozone-containing aqueous solution to the substrate without supplying an ammonia-containing aqueous solution to the substrate.

A 15 th aspect is the substrate processing method according to any one of the 1 st to 14 th aspects, wherein the step of contacting the aqueous solution containing ozone includes: heating the ozone-containing aqueous solution in a pipe distant from the substrate.

A 16 th aspect is the substrate processing method according to any one of the 1 st to 15 th aspects, wherein the step of contacting the aqueous ozone-containing solution includes: and heating the ozone-containing aqueous solution on the substrate.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the above aspect 1, the ammonia-containing aqueous solution is brought into contact with the portion of the resist film that has been brought into contact with the ozone-containing aqueous solution. Since the portion that has been brought into contact with the aqueous solution containing ozone is previously subjected to the decomposition action caused by ozone, it is easy to receive the swelling action caused by the aqueous solution containing ammonia. This promotes the progress of swelling of the resist film. Therefore, the resist film can be removed in a short time in the subsequent steps. Further, the waste liquid treatment load of the ozone-containing aqueous solution and the ammonia-containing aqueous solution is small as compared with SPM. As described above, the resist film can be removed from the substrate in a short time while suppressing the burden of waste liquid treatment.

Drawings

Fig. 1 is a plan view schematically showing the structure of a substrate processing apparatus.

Fig. 2 is a schematic sectional view taken along line II-II of fig. 1.

Fig. 3 is a schematic sectional view taken along line III-III of fig. 1.

Fig. 4 is a cross-sectional view showing an example of the configuration of the spray nozzle of fig. 3.

Fig. 5 is a flowchart schematically showing a substrate processing method in embodiment 1 of the present invention in terms of processing on a part of a resist film.

Fig. 6 is a partial sectional view schematically showing the first step 1 of the substrate processing method according to embodiment 1 of the present invention.

Fig. 7 is a partial sectional view schematically showing the 2 nd step of the substrate processing method according to embodiment 1 of the present invention.

Fig. 8 is a partial sectional view schematically showing the 3 rd step of the substrate processing method according to embodiment 1 of the present invention.

Fig. 9 is a partial sectional view schematically showing the 4 th step of the substrate processing method according to embodiment 1 of the present invention.

Fig. 10 is a flowchart schematically showing a substrate processing method according to embodiment 1 of the present invention in terms of the operation of the substrate processing apparatus.

Fig. 11 is a plan view schematically showing operation 1 of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 12 is a plan view schematically showing action 2 of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 13 is a plan view schematically showing action 3 of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 14 is a plan view schematically showing action 4 of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 15 is a plan view schematically showing the 5 th action of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 16 is a plan view schematically showing action 6 of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 17 is a plan view schematically showing action 7 of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 18 is a plan view schematically showing operation 8 of the substrate processing apparatus according to embodiment 1 of the present invention.

Fig. 19 is a flowchart schematically showing a substrate processing method in embodiment 2 of the present invention in terms of the operation of the substrate processing apparatus.

Fig. 20 is a plan view schematically showing action 1 of the substrate processing apparatus according to embodiment 2 of the present invention.

Fig. 21 is a plan view schematically showing action 2 of the substrate processing apparatus according to embodiment 2 of the present invention.

Fig. 22 is a plan view schematically showing action 3 of the substrate processing apparatus according to embodiment 2 of the present invention.

Fig. 23 is a flowchart schematically showing a substrate processing method according to embodiment 3 of the present invention in terms of the operation of the substrate processing apparatus.

Fig. 24 is a flowchart schematically showing a substrate processing method according to embodiment 4 of the present invention in terms of the operation of the substrate processing apparatus.

Fig. 25 is a flowchart schematically showing a substrate processing method according to embodiment 5 of the present invention in terms of the operation of the substrate processing apparatus.

Fig. 26 is a partial sectional view schematically showing one step of the substrate processing method according to embodiment 5 of the present invention.

Fig. 27 is a flowchart schematically showing a substrate processing method in embodiment 6 of the present invention in terms of the operation of the substrate processing apparatus.

Fig. 28 is a flowchart schematically showing a substrate processing method in embodiment 6 of the present invention in terms of processing a part of a resist film.

Fig. 29 is a partial sectional view schematically showing one step of the substrate processing method according to embodiment 6 of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding portions are denoted by the same reference numerals, and description thereof will not be repeated.

< substrate processing apparatus >

First, an example of a substrate processing apparatus applicable to embodiments 1 to 6 described later will be described below. In each embodiment, it is not necessary to use all functions of the substrate processing apparatus described below. Therefore, in each embodiment, unnecessary portions of the mechanism of the substrate processing apparatus can be omitted.

Fig. 1 is a plan view schematically showing the structure of a substrate processing apparatus according to embodiment 1 of the present invention. Fig. 2 and 3 are schematic cross-sectional views taken along line II-II and line III-III of fig. 1, respectively. In the figure, a wafer 901 (substrate) to be processed by a substrate processing apparatus is also shown. A resist film (not shown in fig. 1 to 3) is provided on the wafer 901 before processing. The resist film is removed by substrate processing using a substrate processing apparatus. The substrate processing apparatus includes a support unit 10, a discharge unit 30, and a spray unit 40.

The support 10 has a rotary shaft 16, a spin base 13, a chuck 12, a back nozzle 11, a hot water supply source 101, a deionized water supply source 102, a valve 111, and a valve 112. The rotary shaft 16 is rotated by a motor (not shown). The spin base 13 is attached to a spin shaft 16. The chuck 12 is mounted near the outer edge of the spin base 13 and holds the wafer 901. With these configurations, the wafer 901 is supported by the support 10 so as to be rotatable (see arrow SP). The back nozzle 11 ejects a fluid, particularly a liquid, toward the back surface of the wafer 901. The spin base 13 is provided with an opening OP so as not to hinder the ejection. The hot water supply source 101 supplies hot water to the back nozzle 11 via a valve 111. The deionized water supply source 102 supplies deionized water to the back nozzle 11 via a valve 112.

The ejection part 30 has an ejection nozzle 31, an arm 32, a rotation shaft 33, an actuator 34, an ozone water supply part 301, an additive supply part 302, an SC1 supply part 303, a deionized water supply part 304, a valve 311, a valve 312, a valve 313, a valve 314, a liquid pipe 320, and a heater 331. The ejection nozzle 31 is connected to the liquid pipe 320, and ejects the liquid supplied from the liquid pipe 320 onto the wafer 901. The arm 32 connects the discharge nozzle 31 and the rotation shaft 33. The rotation angle of the rotating shaft 33 is adjusted by an actuator 34. With these configurations, the discharge nozzle 31 can perform a scanning operation substantially along the radial direction of the wafer 901 (see fig. 1).

The ozone water supply unit 301 supplies ozone water to the liquid pipe 320 via the valve 311. Additive supply 302 supplies additive to liquid pipe 320 via valve 312. The additive may be a liquid. SC1 supply unit 303 supplies an SC1(Standard Clean 1) cleaning liquid to liquid pipe 320 via valve 313. The SC1 cleaning solution is a mixture of ammonia water, hydrogen peroxide water, and water. The deionized water supply portion 304 supplies deionized water to the liquid pipe 320 via the valve 314.

The heater 331 is a mechanism for heating the ozone water from the ozone water supply unit 301. The heater 331 is preferably installed between the valve 311 and the liquid pipe 320. Here, the valve 311 may be a valve closest to the liquid pipe 320 among at least 1 valve installed between the ozonated water supply part 301 and the liquid pipe 320. The heater 331 may be disposed upstream of a portion where the pipes from the additive supply unit 302, the SC1 supply unit 303, and the deionized water supply unit 304 join, or may be disposed downstream of the portion in the pipe between the ozone water supply unit 301 and the liquid pipe 320. In the former case, only the ozone water can be selectively heated, and in the latter case, the mixed liquid can be heated. The heater 331 is, for example, a lamp heater or an LED heater.

The spraying section 40 includes a spraying nozzle 41, an arm 42, a rotary shaft 43, an actuator 44, an ammonia water supply section 401, a hydrogen peroxide water supply section 402, an SC1 cleaning liquid supply section 403, a gas supply section 409, a valve 411, a valve 412, a valve 413, and a valve 419. The spray nozzle 41 is a two-fluid nozzle that discharges two fluids of the liquid supplied from the liquid pipe 420 and the gas supplied from the gas pipe 429. Preferably the two fluids are mixed with each other, thereby creating a flow of gas and droplets dispersed to the gas.

The arm 42 connects the spray nozzle 41 and the rotary shaft 43. The rotation angle of the rotating shaft 43 is adjusted by an actuator 44. With these configurations, the spray nozzle 41 can perform a scanning operation substantially along the radial direction of the wafer 901 (see fig. 1).

The ammonia water supply unit 401 supplies ammonia water to the liquid pipe 420 via the valve 411. The temperature of the supplied ammonia water is preferably at least room temperature and at most 40 ℃. The hydrogen peroxide water supply unit 402 supplies hydrogen peroxide water to the liquid pipe 420 via the valve 412. The temperature of the supplied hydrogen peroxide water is preferably room temperature or higher and 80 ℃ or lower. The SC1 cleaning liquid supply section 403 supplies the SC1 cleaning liquid to the liquid pipe 420 via the valve 413. The gas supply unit 409 supplies gas to the gas pipe 429 via a valve 419. The gas supplied from the gas supply part 409 may be an inert gas, such as nitrogen (N)₂) A gas.

Fig. 4 is a sectional view showing an example of the configuration of the spray nozzle 41 (fig. 3). The spray nozzle 41 has a liquid nozzle portion 41L, a gas nozzle portion 41G, and a gas inlet 41i for spraying from the spray outlet OS.

The liquid nozzle portion 41L has a through hole HL. One end of the through hole HL is connected to the liquid pipe 20, and the other end of the through hole HL reaches the spray opening OS.

The gas nozzle portion 41G has an annular hole HG surrounding the liquid nozzle portion 41L. The annular hole HG is connected to the gas inlet 41 i. To spray outlet OS. The extension direction of the outlet portion of the annular hole HG (see the dotted line arrow in the figure) and the extension direction of the outlet portion of the through hole HL (see the solid line arrow in the figure) intersect each other below the spray nozzle 41. With this configuration, the gas discharged from the gas nozzle portion 41G collides with the liquid discharged from the liquid nozzle portion 41L. Thereby, a flow AS of gas and droplets dispersed to the gas is generated.

In the above description, the case where the mechanism for the scanning operation of the discharge nozzle 31 and the mechanism for the scanning operation of the spray nozzle 41 are separately provided has been described, but as a modification, a common scanning mechanism may be provided for performing the scanning operation of both the discharge nozzle 31 and the spray nozzle 41. In other words, the discharge nozzle 31 and the spray nozzle 41 may be attached to a common arm that can perform a scanning operation. In this case, it is preferable that the discharge nozzle 31 and the spray nozzle 41 are installed so that a region directly receiving the discharge from the discharge nozzle 31 and a region directly receiving the spray from the spray nozzle 41 are separated from each other. This prevents the fluid flowing from the discharge nozzle 31 to the wafer 901 and the fluid flowing from the spray nozzle 41 to the wafer 901 from interfering with each other unnecessarily in the middle of the path. Even when the discharge nozzle 31 and the spray nozzle 41 can independently perform the scanning operation as shown in fig. 1, for the above-described reason, it is preferable to control the scanning operation of both the discharge nozzle 31 and the spray nozzle 41 so as to maintain a state in which the region directly receiving the discharge from the discharge nozzle and the region directly receiving the spray from the spray nozzle 41 are separated from each other.

< embodiment 1 >

Fig. 5 is a flowchart schematically showing the substrate processing method in embodiment 1 in terms of performing processing on the portion P1 (fig. 6) of the resist film 902. Fig. 6 to 9 are partial sectional views schematically showing steps 1 to 4 of the substrate processing method according to embodiment 1.

Referring to fig. 6, first, a wafer 901 provided with a resist film 902 containing a portion P1 is prepared. The resist film 902 may have a pattern shape (not shown) on the wafer 901. Further, the resist film 902 may be a film modified by being used as an etching mask or an implantation mask, for example. In general, removal of the resist film becomes more difficult due to the modification.

Referring to fig. 7, in step T21 (fig. 5), the aqueous ozone-containing solution 920 is brought into contact with at least a portion P1 of the resist film 902. For this purpose, an aqueous solution 920 containing ozone is discharged toward the wafer 901. The portion P1 of the resist film 902 that has been in contact with the aqueous ozone-containing solution 920 is subjected to decomposition by ozone. Specifically, the C (carbon) -C bond in the resist film 902 is cut by the ozone radicals. It is preferable that cracks be formed in the resist film 902 by the decomposition action of the ozone-containing aqueous solution 920. In other words, the resist film 902 is preferably subjected to a decomposition action by the ozone-containing aqueous solution 920 until cracks are generated in the resist film 902. Here, the ozone-containing aqueous solution 920 preferably contains substantially no ammonia water, and the ozone-containing aqueous solution 920 preferably contains substantially no hydrogen peroxide water, and may be, for example, pure ozone water generated by dissolving ozone in deionized water.

Referring to fig. 8, next in step T31 (fig. 5), an aqueous ammonia-containing solution is brought into contact with the portion P1 of the resist film 902. For this purpose, an ammonia-containing aqueous solution is ejected toward the wafer 901. Specifically, droplets 930S of the aqueous ammonia-containing solution are brought into contact with the portion P1. The ammonia-containing aqueous solution contains ammonia at a higher concentration than the ozone-containing aqueous solution 920. As described above, the ozone-containing aqueous solution 920 may not contain ammonia. The resist film 902 that has been in contact with the aqueous ammonia-containing solution is subjected to a treatment with NH in the aqueous ammonia-containing solution₄Swelling by OH. Preferably, this swelling action is accompanied by the invasion of cracks of the aqueous ammonia-containing solution into the resist film 902 formed in step T21 described above.

In other parts on the wafer 901, the ammonia-containing aqueous solution is brought into contact with the ozone-containing aqueous solution 920 (fig. 7) supplied in step T21, whereby the decomposition action by ozone in the ozone-containing aqueous solution 920 can be temporarily activated. Further, the ammonia-containing aqueous solution may contain hydrogen peroxide water, thereby enhancing the swelling action and temporarily further activating the decomposition action.

As described above, the steps T21 and T31 are performed. Thereafter, the set of steps T21 and T31 may be repeated any number of times.

Referring to fig. 9, next, in step T32 (fig. 5), a portion P1 of the resist film 902 is separated (peeled) from the wafer 901 by physical cleaning. Here, the physical cleaning mainly means cleaning by a mechanical action. The step of physical cleaning preferably includes a step of blowing a gas onto the wafer 901, and more preferably a step of spraying droplets 930S of an ammonia-containing aqueous solution onto the wafer 901 with the gas. The gas is preferably an inert gas, e.g. N₂A gas.

By applying the above-described steps T21, T31, and T32 (fig. 5) to the portion of the resist film 902 that should be peeled, a desired portion (typically, the entire portion) of the resist film 902 is peeled. This ends the resist film 902 peeling process.

Each of step T21, step T31, and step T32 (fig. 5) need not be performed simultaneously throughout the resist film 902, but may be performed at any timing in each part of the resist film 902. In this case, a substrate process using the substrate processing apparatus (fig. 1 to 3) will be described as an example.

Fig. 10 is a flowchart schematically showing a substrate processing method according to embodiment 1 in terms of the operation of the substrate processing apparatus (fig. 1 to 3). Fig. 11 to 18 are plan views schematically showing the 1 st to 8 th operations of the substrate processing apparatus according to embodiment 1. In fig. 11 to 18, the positions of the discharge nozzle 31 and the spray nozzle 41 are indicated by dots with respect to the substrate processing apparatus (fig. 1 to 3), and the other structures are not illustrated.

Referring to fig. 11, a wafer 901 (fig. 6) provided with a resist film 902 having a portion P1 is mounted on a substrate processing apparatus (fig. 1 to 3). The wafer 901 is rotated (see arrow SP in the figure). Accompanying this, the position of the portion P1 is rotated about the center of the wafer 901. The number of rotations per minute is, for example, about 800 rpm.

Referring to fig. 12, in step S20 (fig. 10), the ozone water as the ozone-containing aqueous solution 920 (fig. 7) starts to be discharged from the discharge nozzle 31. In this case, the discharge nozzle 31 is preferably disposed near the center of the wafer 901. The ozone-containing aqueous solution 920 is gradually spread outward on the wafer 901 by the centrifugal force. From the viewpoints of shortening the time required for the peeling of the resist film 902 and suppressing unnecessary etching to the wafer 901 which is the base of the resist film 902, it is preferable that the ozone concentration of the ozone water is set to a sufficiently high concentration, for example, about 100 ppm. The discharge amount of the ozone water is preferably 3 liters/minute or less. The ozone water as the ozone-containing aqueous solution 920 may be heated by the heater 331 (fig. 2) in a pipe between the ozone water supply unit 301 (fig. 2) and the discharge nozzle 31 and distant from the wafer 901. The heating may be continued during the ejection of the aqueous ozone containing solution 920. The ozone-containing aqueous solution 920 may be heated on the wafer 901 instead of in the above-described piping, or may be heated on the wafer 901 and heated in the above-described piping. For this purpose, a heater for radiating heat to the upper surface of the wafer 901 may be provided in the substrate processing apparatus. The heater may be remote from the piping. As described later, the wafer 901 may be heated by warm water (or other heated liquid) from the back nozzle 11 (fig. 3) instead of the heater, or the wafer 901 may be heated by the heater and warm water (or other heated liquid) from the back nozzle 11 (fig. 3). Thereby, the liquid on the wafer 901 is also heated. In embodiment 1, the step of bringing the aqueous solution containing ozone 920 into contact with the portion P1 in step S20 is performed by supplying the aqueous solution containing ozone 920 from the spray nozzle 31 to the wafer 901, instead of supplying the aqueous solution containing ammonia from the spray nozzle 41 to the wafer 901.

Referring to FIG. 13, the ozone-containing aqueous solution 920 expands as described above, and as a result, the ozone-containing aqueous solution 920 is brought into contact with the portion P1 (FIG. 5: step T21). Further, as shown, the aqueous ozone containing solution 920 preferably covers the entire upper surface of the wafer 901.

Referring to fig. 14, in step S30 (fig. 10), N is used as a gas₂An aqueous ammonia peroxide solution (a mixed solution of aqueous ammonia and aqueous hydrogen peroxide) as an aqueous ammonia solution is sprayed from the spray nozzle 41. In other words, droplets 930S (fig. 8) of aqueous ammonia peroxide are sprayed. Thereby, the ammonia-containing aqueous solution 930 is locally supplied onto the wafer 901 in the vicinity of the spray nozzle 41. In this spraying, the ozone-containing aqueous solution 920 can be continuously discharged from the discharge nozzle 31. The amount of spray is preferably 20 ml/min or more and 300 ml/min or less. The number of rotations per minute of the wafer 901 in step S30 may be lower than that in the aforementioned step S20, for example, about 500 rpm.

By receiving the spray, the ozone-containing aqueous solution 920 is substantially removed from the area near the spray nozzle 41 on the upper surface of the wafer 901 (the area directly receiving the spray). Further, the ammonia-containing aqueous solution 930 and the ozone-containing aqueous solution 920 which extend to the outside of the vicinity region are mixed with each other. Note that at the time point shown in fig. 14, part of P1 has not yet been in contact with aqueous ammonia-containing solution 930.

In the above step, the ozone water from the spray nozzle 31 and the aqueous ammonia peroxide solution (ammonia water and aqueous hydrogen peroxide solution) from the spray nozzle 41 are supplied onto the wafer 901. The ratio (volume ratio) of the ammonia water to the hydrogen peroxide water may be the same degree. In this case, the ratio (volume ratio) of the ozone water to the ammonia water to the hydrogen peroxide water is, for example, about 2000:10:10 in the case of the condition of a large amount of ozone water, and about 500:125:125 in the case of the condition of a small amount of ozone water. Here, the ammonia water has a concentration of about 28 wt%, and the hydrogen peroxide water has a concentration of about 30 wt%, for example. An ammonia-containing aqueous solution containing no hydrogen peroxide water may be used, and for example, ammonia water may be used instead of the ammonia hydrogen peroxide aqueous solution.

Referring to FIG. 15, when the position of the portion P1 in a plan view (the view of FIG. 15) is sufficiently close to the position of the spray nozzle 41 with the rotation of the wafer 901, the portion P1 comes into contact with the ammonia-containing aqueous solution 930 (FIG. 5: step T31).

Referring to fig. 16, when the position of the portion P1 is sufficiently distant from the position of the spray nozzle 41 in a plan view (the view in fig. 16) accompanying the rotation of the wafer 901, the portion P1 is again brought into contact with the ozone-containing aqueous solution 920 (fig. 5: step T21). By repeating this operation, the steps of fig. 15 and 16 corresponding to step T21 and step T31 (fig. 5) can be repeated a plurality of times.

Referring to fig. 17, when the position of the spray nozzle 41 in the radial direction is shifted from the position of the portion P1 to some extent in accordance with the movement, that is, the scanning operation, of the spray nozzle 41 that ejects the aqueous ammonia solution, the spray of the aqueous ammonia solution is not supplied to the portion P1. Instead, another portion P2 was supplied with a spray of aqueous ammonia-containing solution. Thus, the same processing as that in the portion P1 can be performed also in the portion P2.

Referring to fig. 18, with the scanning operation of the spray nozzle 41 again, the spray of the aqueous ammonia solution is again supplied from the spray nozzle 41 to the portion P1. The spray collides with droplets 930S (fig. 9) directed toward resist film 902. In other words, collision occurs with the aerosol flow of droplets 930S toward resist film 902. The spray thus acts on the resist film 902 as a physical rinse. With this physical cleaning, the portion P1 is separated (peeled) from the wafer 901.

The portion P2 (fig. 17) is similarly separated in accordance with the scanning operation of the spray nozzle 41. The scanning operation is preferably performed so that the ammonia-containing aqueous solution 930 is ejected to the peripheral edge portion of the wafer 901 for a longer time than the central portion of the wafer 901. In other words, the time during which the spray nozzle 41 that ejects the ammonia-containing aqueous solution 930 is positioned above the peripheral portion of the wafer 901 is preferably longer than the time during which it is positioned above the central portion of the wafer 901. For example, the arrangement of the spray nozzles shown in fig. 18 is maintained for a longer time than the arrangement of the spray nozzles 41 shown in fig. 17. In the arrangement of the spray nozzles shown in fig. 18, the spray nozzles 41 are arranged radially closer to the peripheral edge than the arrangement of the spray nozzles 41 shown in fig. 17.

The process of peeling off the resist film 902 (fig. 6) as a whole is completed as described above.

In the above description, the scanning operation of the spray nozzle 41 is described, but the discharge nozzle 31 may perform the scanning operation as shown by an arrow SN (fig. 14 to 18), for example. When both the spray nozzle 41 and the discharge nozzle 31 perform the scanning operation, the relative positions of the spray nozzle 41 and the discharge nozzle 31 may be fixed or may be changed. When the relative positions of the spray nozzle 41 and the discharge nozzle 31 are fixed, a common mechanism for performing the scanning operation can be used; when the relative positions of the spray nozzle 41 and the discharge nozzle 31 vary, the degree of freedom for optimizing the scanning operation can be increased.

Here, in at least a part of the period during which the liquid is supplied from both the discharge nozzle 31 and the spray nozzle 41, the discharge nozzle 31 is preferably located closer to the center of the wafer 901 than the spray nozzle 41. More preferably, the discharge nozzle 31 is located closer to the center of the wafer 901 than the spray nozzle 41 in half or more of the period. In the above period, the discharge nozzle 31 may be always positioned closer to the center of the wafer 901 than the spray nozzle 41. Thereby, the range over which the ozone-containing aqueous solution 920 from the discharge nozzle 31 spreads due to the centrifugal force easily includes the position of the spray nozzle 41 in the radial direction. Therefore, the probability that the area having been in contact with the aqueous ozone-containing solution 920 receives the mist from the mist spray nozzle 41 can be increased.

The period of supplying the liquid from both the discharge nozzle 31 and the spray nozzle 41 may be a period of simultaneously discharging the liquid from both the discharge nozzle 31 and the spray nozzle 41, or may be a period of alternately supplying the liquid from both the discharge nozzle 31 and the spray nozzle 41 at short intervals so that the liquids from both the nozzles sufficiently coexist on the wafer 901 instead of or simultaneously with this.

During the above-described process, hot water may be supplied from the back nozzle 11 (fig. 2 and 3) to the back surface of the wafer 901. This can increase the temperature of the wafer 901 during processing. For example, warm water of about 80 ℃ is sprayed at about 2 liters/minute.

Next, in step S80, the ejection nozzle 31 ejects deionized water. Thereby, the wafer 901 is washed with water. During this process, deionized water may be supplied from the backside nozzle 11 (fig. 2 and 3) onto the backside of the wafer 901. Further, the spraying from the spray nozzle 41 may be stopped during the treatment. The number of rotations per minute of the wafer 901 in step S80 may be higher than that in the aforementioned step S30, for example, around 800 rpm.

Next, in step S90, the deionized water discharge from the discharge nozzle 31 and the back surface nozzle 11 is stopped, and the wafer 901 is rotated at a high speed of, for example, about 2500 rpm. Thereby removing liquid from wafer 901 using centrifugal force. That is, the wafer 901 is dried. The drying step may include a step of ejecting a volatile liquid such as isopropyl alcohol from the ejection nozzle 31, thereby suppressing the generation of water stains.

The operation of the substrate processing apparatus (fig. 1 to 3) is terminated as described above (fig. 10).

According to the present embodiment, the ammonia-containing aqueous solution 930 (fig. 14) is brought into contact with the portion P1 (fig. 13) of the resist film 902 (fig. 6) that has been brought into contact with the ozone-containing aqueous solution 920 (fig. 7). The portion P1 is susceptible to the swelling action by the ammonia-containing aqueous solution 930 because it is previously subjected to the decomposition action by ozone. This promotes the progress of swelling of the resist film 902. Therefore, the resist film 902 can be removed in a short time in the subsequent steps. Further, the burden of waste liquid treatment of the ozone-containing aqueous solution 920 and the ammonia-containing aqueous solution 930 is smaller than that of SPM. As described above, the resist film 902 can be removed from the wafer 901 in a short time while suppressing the burden of waste liquid treatment.

When the entire resist film is to be decomposed depending on the decomposition action of ozone, if the thickness of the resist film is large to some extent, the treatment time becomes very long. This can be particularly problematic in monolithic substrate processing. In the present embodiment, the resist film 902 is swollen, and the residual thereof is peeled off (see fig. 9), instead of being decomposed as a whole. This eliminates the need to decompose the resist film until the resist film disappears as a whole. Therefore, the treatment can be performed in a short time as described above.

The step of contacting the ozone-containing aqueous solution 920 (fig. 13) is performed by discharging the ozone-containing aqueous solution 920 toward the wafer 901 from the discharge nozzle 31 (fig. 1 and 2). Thus, the ozone-containing aqueous solution 920 can be used in a method suitable for the single-wafer substrate processing.

The step of contacting the aqueous ammonia-containing solution 930 (fig. 15) is performed by ejecting the aqueous ammonia-containing solution 930 from the spray nozzle 41 (fig. 1 and 3) toward the wafer 901. Thereby, the ammonia-containing aqueous solution 930 can be used in a method suitable for the single-wafer substrate processing.

The step of discharging the aqueous ammonia solution 930 (fig. 17 and 18) includes a step of moving the spray nozzle 41 that discharges the aqueous ammonia solution 930, specifically, a step of performing a scanning operation. This enables the ammonia-containing aqueous solution 930 to be locally and intensively supplied onto the wafer 901 at each time point, and also enables the ammonia-containing aqueous solution 930 to be supplied onto the wafer 901 over a wide range by the movement of the spray nozzle 41. Therefore, the peeling effect can be locally improved, and the peeling treatment can be performed over a wide range on the wafer 901.

The step of moving the spray nozzle 41 is preferably performed so that the time for spraying the ammonia-containing aqueous solution 930 to the peripheral edge portion of the wafer 901 is longer than that in the central portion of the wafer 901. This can suppress the nonuniformity of the supply amount of the ammonia-containing aqueous solution 930 (fig. 17 and 18) on the wafer 901. Therefore, the processing can be performed more uniformly on the wafer 901.

A portion P1 in the resist film 902, which has been brought into contact with the aqueous ammonia-containing solution 930 by the process of contacting the aqueous ammonia-containing solution 930 (fig. 13), is separated from the wafer 901 by physical cleaning (fig. 9). Since the resist film 902 has been sufficiently swelled by the swelling process (fig. 8), it is easily peeled off by physical cleaning. Therefore, the resist film 902 can be peeled off in a shorter time.

The physical cleaning (fig. 9) includes a step of blowing a gas from the spray nozzle 41 (fig. 1 and 3) toward the wafer 901. Thus, compared to the case where a fluid made of only a liquid is blown or a fluid containing a solid is blown, damage to the wafer 901 can be suppressed while securing a sufficient cleaning force.

The step of blowing the gas onto the wafer 901 includes a step of spraying droplets 930S (fig. 8 and 9) of the ammonia-containing aqueous solution onto the wafer 901 with the gas. Thereby, the droplets 930S dispersed in the gas collide with the wafer 901. In the step of fig. 8, the ammonia-containing aqueous solution is pushed into the resist film 902 further by the gas pressure. Therefore, swelling is likely to occur even in the deep portion of the resist film 902. Further, the ozone-containing aqueous solution 920 is drained from the portion of the upper surface of the wafer 901, which is directly touched by the gas flow, by the pressure of the gas. Thereby, the swelling action of the ammonia-containing aqueous solution 930 due to the action of ozone in the portion can be prevented from being hindered. Therefore, the progress of swelling can be promoted. In the step of fig. 9, since the droplets 930S are included in the gas flow, the effect of physical cleaning can be improved.

The gas is preferably an inert gas. Thereby, unnecessary chemical reactions between the gas and the wafer 901 can be avoided.

The step of contacting the aqueous ozone-containing solution 920 (fig. 7) preferably includes a step of forming cracks in the resist film 902 by the aqueous ozone-containing solution 920. This enables the ammonia-containing aqueous solution 930 (fig. 15) to penetrate through the crack. Therefore, swelling of the resist film 902 by the ammonia-containing aqueous solution 930 can be promoted (see fig. 8).

The aqueous ammonia-containing solution 930 preferably contains hydrogen peroxide. This can promote swelling of the resist film 902 by the ammonia-containing aqueous solution 930 (see fig. 8). Further, the ammonia-containing aqueous solution 930 (fig. 15) sprayed from the spray nozzle 41 spreads over the wafer 901, thereby being mixed into the ozone-containing aqueous solution 920. This activates the decomposition action of the resist film 902 by the ozone-containing aqueous solution 920.

The step of contacting the ozone-containing aqueous solution 920 (fig. 12) includes: a step of supplying the ozone-containing aqueous solution 920 to the wafer 901 without supplying the ammonia-containing aqueous solution 930 to the wafer 901 (FIG. 14) (FIG. 10: step S20). This enables a large amount of the aqueous solution 920 containing ozone to be supplied to the wafer 901 before the action of the aqueous solution 930 containing ammonia is received. Therefore, before step S30 (fig. 10), the decomposition action by ozone can be sufficiently applied to the resist film 902 (fig. 7) in advance.

The step of contacting the ozone-containing aqueous solution 920 (fig. 12 to 18) may include a step of heating the ozone-containing aqueous solution 920 in a pipe distant from the wafer 901. This can enhance the decomposition action of the resist film 902 (fig. 7) by the ozone-containing aqueous solution 920.

The step of contacting the ozone-containing aqueous solution (fig. 12 to 18) may include a step of heating the ozone-containing aqueous solution 920 on the wafer 901. This can enhance the decomposition action of the resist film 902 (fig. 7) by the ozone-containing aqueous solution 920 by heating, and can suppress ozone deactivation due to the passage of time after heating, as compared with the case where heating is performed before the ozone-containing aqueous solution 920 is supplied onto the wafer 901 (for example, the case where heating is performed by the heater 331 (fig. 2)).

< embodiment 2 >

Fig. 19 is a flowchart schematically showing a substrate processing method according to embodiment 2 in terms of the operation of the substrate processing apparatus (fig. 1 to 3). This flow corresponds to the flow in which step S20 (fig. 10) is omitted from the flow in embodiment 1. Therefore, only the differences associated with the omission will be described below, and the description of the same features as those of embodiment 1 will be omitted.

Fig. 20 to 22 are plan views schematically showing the 1 st to 3 rd operations of the substrate processing apparatus according to embodiment 2, respectively. In fig. 20 to 22, only the positions of the discharge nozzle 31 and the spray nozzle 41 are shown by dots in the substrate processing apparatus (fig. 1 to 3), and the other configurations are not shown.

Referring to fig. 20, first, a wafer 901 (fig. 6) provided with a resist film 902 having a portion P1a and a portion P1b is mounted on a substrate processing apparatus (fig. 1 to 3). The wafer 901 is rotated (see arrow SP in the figure). Accompanying this, the positions of portion P1a and portion P1b rotate about the center of wafer 901. In step S30 (fig. 19), the ejection of ozone water as the ozone-containing aqueous solution 920 (fig. 7) from the ejection nozzle 31 is started. Substantially simultaneously, using N as the gas₂The spraying of the aqueous ammonia peroxide solution (mixed liquid of aqueous ammonia and aqueous hydrogen peroxide) as the aqueous ammonia-containing solution 930 from the spray nozzle 41 is started.

Referring to fig. 21, the portion P1a is initially not in contact with the aqueous ammonia-containing solution 930 but in contact with the aqueous ozone-containing solution 920. This case is the same as the case of the part P1 (fig. 13). Therefore, the process for the portion P1a is substantially the same as the process for the portion P1 in embodiment 1. On the other hand, part of P1b was initially not in contact with ozone-containing aqueous solution 920 but in contact with aqueous ammonia-containing solution 930.

Referring to fig. 22, next, portion P1b is first contacted with ozone-containing aqueous solution 920. In other words, step T21 (FIG. 5) is performed on portion P1 b. The subsequent processing of portion P1b is substantially the same as that of portion P1. That is, the portion P1b was also subjected to substantially the same treatment as the treatment of the portion P1, except that the aqueous ammonia-containing solution 930 was not initially contacted with the aqueous ozone-containing solution 920.

According to the present embodiment, unlike the case of embodiment 1 (fig. 12), the step of contacting the ozone-containing aqueous solution (fig. 20) is performed by supplying the ammonia-containing aqueous solution 930 to the wafer 901 while supplying the ozone-containing aqueous solution 920 to the wafer 901. This makes it possible to omit step S20 (fig. 10: embodiment 1). In the present embodiment, although it is difficult to supply a large amount of the aqueous solution 920 containing ozone to the wafer 901 before the action of the aqueous solution 930 containing ammonia is received, substantially the same effect as that of embodiment 1 can be obtained by sufficiently supplying the aqueous solution 920 containing ozone after that.

< embodiment 3 >

Fig. 23 is a flowchart schematically showing a substrate processing method according to embodiment 3 in terms of the operation of the substrate processing apparatus (fig. 1 to 3). In this embodiment, before step S20 (fig. 10: embodiment 1), Ultraviolet (UV) light is irradiated to the resist film 902 (fig. 6). The wavelength of the ultraviolet light is preferably 190nm or less, for example 172 nm. The irradiation with ultraviolet rays can be performed by using an apparatus different from the substrate processing apparatus (fig. 1 to 3). Since the configurations other than the above are substantially the same as those of embodiment 1, the same reference numerals are given to the same or corresponding elements, and description thereof will not be repeated. As a modification, step S10 (fig. 23) may be performed before step S30 (fig. 19: embodiment 2).

According to this embodiment, the resist film 902 can be more rapidly decomposed (see fig. 7) by the irradiation of ultraviolet light at the time point when the ammonia-containing aqueous solution 930 (fig. 15) is supplied, and specifically, the resist film 902 can be more reliably cracked. Therefore, swelling of the resist film by the ammonia-containing aqueous solution 930 can be promoted (see fig. 8). Therefore, the resist film 902 can be removed in a shorter time.

< embodiment 4 >

Fig. 24 is a flowchart schematically showing a substrate processing method according to embodiment 4 in terms of the operation of the substrate processing apparatus (fig. 1 to 3). In the present embodiment, step S50 is performed between step S30 and step S80. In step S50, the discharge nozzle 31 discharges the SC1 cleaning liquid or deionized water, and the spray nozzle 41 sprays the SC1 cleaning liquid. Thereby, the wafer 901 is cleaned. The flow rate of the ejection nozzle 31 is, for example, about 500 ml/min, and the flow rate of the spray nozzle 41 is, for example, about 100 ml/min. The number of rotations per minute of the wafer 901 in step S80 may be about the same as the aforementioned number of rotations per minute in step S30, for example, about 500 rpm. During this process, SC1 cleaning solution or deionized water may be supplied onto the backside of the wafer 901 from the backside nozzle 11 (fig. 2 and 3). Since the configurations other than the above are substantially the same as those of any of embodiments 1 to 3, the same reference numerals are given to the same or corresponding elements, and the description thereof will not be repeated.

< embodiment 5 >

Fig. 25 is a flowchart schematically showing a substrate processing method according to embodiment 5 in terms of the operation of the substrate processing apparatus (fig. 1 to 3). In the present embodiment, first, step S10 and step S20 are performed in the same manner as in embodiment 3 (fig. 23).

Fig. 26 is a partial sectional view schematically showing one step of the substrate processing method according to embodiment 5. After the above steps, in step S25 (fig. 25), a mixed liquid 930L of ozone water and the additive is discharged from the discharge nozzle 31 (fig. 2). In other words, both valves 311 and 312 (fig. 2) are opened. The additive comprises ammonia water and hydrogen peroxide water. This mixed liquid contains ammonia at a higher concentration than the aqueous solution 920 containing ozone (fig. 7). As described above, the ozone-containing aqueous solution 920 may not contain ammonia. The mixed liquid 930L is supplied in step S25, thereby generating both the decomposition action and the swelling action on the resist film 902. The decomposition action by ozone in the ozone-containing aqueous solution is temporarily activated more by mixing ammonia water and hydrogen peroxide water. Although the temporarily increased activity decreases with the passage of time, the influence of the decrease in activity can be suppressed by sufficiently supplying a new mixed liquid from the discharge nozzle 31.

Then, in step S35 (FIG. 25), the aqueous ammonia peroxide solution is sprayed from the spray nozzle 41, as in the case of step S30 (FIG. 10: embodiment 1). By physical cleaning (fig. 9) caused by this spray, the resist film 902 is separated from the wafer 901. In this spraying, the mixed liquid is continuously discharged from the discharge nozzle 31. By receiving the spray, the mixed liquid is substantially removed from the vicinity of the spray nozzle 41 on the upper surface of the wafer 901. Further, the ammonia-containing aqueous solution 930 having spread to the outside of the vicinity is mixed with the mixed liquid, whereby ozone in the mixed liquid 930L is activated more.

Since the subsequent steps are the same as those in embodiment 3 (fig. 23), the description thereof will be omitted. In the present embodiment, step S25 and step S35 are performed instead of step S30 (fig. 23). The replacement of such steps is not limited to embodiment 3, and may be performed in other embodiments described above.

In the present embodiment, in step S25 (fig. 25), the liquid discharged from the discharge nozzle 31 includes ozone water, ammonia water, and hydrogen peroxide water. This makes it possible to simultaneously obtain both the decomposition effect by ozone activated with ammonia water and hydrogen peroxide water and the swelling effect by ammonia water. This enables the resist film 902 to be removed from the wafer 901 in a short time.

< embodiment 6 >

Fig. 27 is a flowchart schematically showing a substrate processing method according to embodiment 6 in terms of the operation of the substrate processing apparatus (fig. 1 to 3). In the present embodiment, the physical cleaning step (fig. 9) in step S35 (fig. 25: embodiment 5) is omitted. In order to compensate for the omission of physical cleaning, the contact with the mixed liquid in step S25 is performed for a longer time (fig. 26). Since the mixed solution contains ammonia water, the mixed solution is one of ammonia-containing aqueous solutions.

Fig. 28 is a flowchart schematically showing a substrate processing method in embodiment 6 in terms of processing at a part of a resist film. Fig. 29 is a partial sectional view schematically showing one step of the substrate processing method according to embodiment 6.

In step U10 (fig. 28), cracks are formed in the resist film 902 (fig. 6 and 7). The step U10 (fig. 28) can be performed by steps S10 and S20 (fig. 27) as operations of the substrate processing apparatus.

Referring to fig. 29, next, in step U11 (fig. 28), mixed liquid 930L, in particular, ammonia water contained in mixed liquid 930L is caused to permeate into the interface between wafer 901 and resist film 902 through the above-described cracks. Thereby, the resist film 902 is peeled from the wafer 901.

According to this embodiment, although the time required for step S25 is slightly longer than that in embodiment 5, the resist film 902 can be peeled from the wafer 901 without using physical cleaning (see fig. 29). Therefore, it is preferable to use embodiment 6 when priority is given to omitting physical cleaning, and to use embodiment 5 when priority is given to shortening the processing time. According to the experimental example made by the inventors of the present application, the time required for the peeling of the resist film is about 4 minutes in the case of embodiment 5, and about 6 minutes in the case of embodiment 6. As a modification, step S50 may be performed between step S25 and step S80 (fig. 24: embodiment 4).

Although the present invention has been described in detail, the above description is illustrative in all cases, and the present invention is not limited to these cases. It should be understood that numerous variations not illustrated are contemplated as being outside the scope of the invention. The respective configurations described in the embodiments and the modifications can be appropriately combined or omitted as long as they are not contradictory to each other.

Description of the reference numerals

11 rear nozzle

31 discharge nozzle

41 spray nozzle

901 wafer (substrate)

331 heater

902 resist film

920 aqueous solution of ozone containing water

930 aqueous solution containing ammonia

930L of mixed solution

930S droplet