WO2007094229A1

WO2007094229A1 - Substrate treating method, and computer-readable storage medium

Info

Publication number: WO2007094229A1
Application number: PCT/JP2007/052215
Authority: WO
Inventors: Yuichiro Inatomi; Mitsuaki Iwashita
Original assignee: Tokyo Electron Limited
Priority date: 2006-02-13
Filing date: 2007-02-08
Publication date: 2007-08-23
Also published as: KR101300892B1; JP4624936B2; KR20080102370A; JP2007214506A

Abstract

A predetermined quantity of pure water is fed onto the central portion of a wafer having a resist pattern formed thereon, and the wafer is rotated to spread the pure water into a circular shape near the central portion of the wafer. Next, the pure water of the wafer is fed with a water-soluble resist pattern size reducing agent. After this, the wafer is rotated at a high speed to spread the resist pattern size reducing agent all over the surface of the wafer. After this, a heating is performed to modify the lower layer portion of the resist pattern size reducing agent near the surface of the resist pattern, into a state insoluble to water, thereby to harden that portion. After this, the unhardened portion of the resist pattern size reducing agent is rinsed and removed with the pure water. Thus, the hardened film is formed on the inner wall face of the recess of the resist pattern so that the resist pattern is reduced in size. In the RELACS technique, the quantity of the resist pattern size reducing agent to be used is reduced to homogenize the pattern sizes in the wafer face.

Description

Specification

Substrate processing method and computer-readable storage medium

Technical field

The present invention relates to a substrate processing method for reducing the size of a resist pattern formed on a substrate, and a computer-readable storage medium storing a computer program for executing the substrate processing method It is about.

Background art

[0002] For example, in a photolithography process in a semiconductor device manufacturing process, a resist film is formed on a wafer, the resist film is exposed, developed, and a resist pattern is formed on a wafer. Speak.

In forming a resist pattern, the resist pattern is required to be miniaturized in order to achieve higher integration of semiconductor devices, and in response to this, the wavelength of the exposure light source has been reduced.

However, at present, there are technical and cost limits to shortening the wavelength of the exposure light source. Therefore, a technology that reduces the dimensions of the resist pattern, such as the hole diameter and line width, is formed by forming a film layer that also has a water-soluble resist pattern size reducing agent on the inner walls of the resist pattern holes and grooves. "Resolution Ennancement Lithgraphy Assisted by Chemical Shrink" technology has been proposed (see Patent Document 1).

[0004] In this RELACS technology, for example, a predetermined resist pattern size reducing agent (RELACS agent) is supplied to the center of the wafer, and the resist pattern size reducing agent is applied to the entire surface of the wafer by rotating the wafer. . Then, for example, the resist pattern size reducing agent on the inner wall surface of the hole or groove is insolublely cured by heat, and then the other uncured resist pattern size reducing agent is removed with pure water, so that the resist pattern dimension is reduced. Has been reduced.

Patent Document 1: Japanese Patent Laid-Open No. 2003-234279

Disclosure of the invention

Problems to be solved by the invention However, when the RELACS technology as described above is used, the resist pattern dimension reducing agent has high water repellency with respect to the underlying resist. The resist pattern size reducing agent could not be properly applied to the entire surface of the film. The resist pattern size reducing agent is an extremely expensive material, and as a result, the cost required for wafer processing for reducing the resist pattern has increased. In addition, the resist pattern size reducing agent is difficult to apply uniformly over the entire surface of the wafer due to water repellency, and the final resist pattern size may vary within the wafer surface.

[0006] The present invention has been made in view of the strong point, and when the size of the resist pattern is reduced using the RELACS technology, the amount of the resist pattern size reducing agent used is reduced. The purpose is to make the dimensions of the resist pattern uniform within the substrate surface.

Means for solving the problem

In order to achieve the above object, the present invention provides a substrate processing method for reducing the size of a resist pattern formed on a substrate, wherein pure water is applied to the substrate on which the resist pattern is formed. Supplying pure water, and then applying a resist pattern size reducing agent to the entire surface of the substrate by supplying a water-soluble resist pattern size reducing agent onto the substrate, rotating the substrate, and thereafter An alteration process in which the lower layer portion of the resist pattern size reducing agent in contact with the surface of the resist pattern is altered insoluble to the removal liquid, and then the upper layer portion of the resist pattern dimension reducing agent that has not been altered is removed by the removal liquid. And a removal step.

[0008] According to the present invention, pure water is supplied onto the substrate, and then a water-soluble resist pattern size reducing agent is supplied, so that pure water and the resist pattern size reducing agent are mixed on the substrate. Further, the wettability of the resist pattern dimension reducing agent to the base is improved. As a result, the resist pattern size reducing agent can be spread over the entire surface of the substrate even in a small amount, and the amount of resist pattern size reducing agent used can be reduced. In addition, since the resist pattern size reducing agent spreads easily over the entire surface of the substrate, the resist pattern size reducing agent can be applied uniformly within the substrate surface, and finally the resist pattern size can be made uniform within the substrate surface. The

[0009] The pure water supply step includes a step of rotating the substrate to expand the pure water supplied onto the substrate to such an extent that it does not spread over the entire surface of the substrate. Alternatively, the resist pattern size reducing agent may be supplied to pure water, and the resist pattern size reducing agent may be spread over the entire surface of the substrate by rotating the substrate.

[0010] In the substrate processing method, after the resist pattern size reducing agent spreads over the entire surface of the substrate in the coating step, the substrate is rotated at a first rotation speed to increase the film thickness of the resist pattern size reducing agent. It is preferable to have a step of adjusting and a step of drying the resist pattern size reducing agent by rotating at a second rotation speed higher than the first rotation speed.

[0011] After the resist pattern size reducing agent spreads over the entire surface of the substrate in the coating step, the rotational speed of the substrate is once reduced, and then the substrate is increased to the first rotational speed to increase the resist pattern. Adjust the film thickness of the dimension reducing agent.

[0012] When drying the resist pattern size reducing agent, a dry gas may be supplied to the outer peripheral portion of the substrate.

[0013] At least when the resist pattern size reducing agent is dried, the ambient atmosphere of the substrate may be set to a humidity of 40% or less.

[0014] In the substrate processing method described above, for example, the control unit of the force substrate processing system executed in the substrate processing system controls the substrate processing system according to the computer program to be executed.

Therefore, the present invention according to another aspect is a computer-readable storage medium storing a computer program for executing the above-described substrate processing method in a substrate processing system.

The invention's effect

[0015] According to the present invention, it is possible to reduce the cost for reducing the size of a resist pattern using the RELACS technology. In addition, a resist pattern having no variation within the substrate surface can be formed to improve yield.

Brief Description of Drawings FIG. 1 is a plan view showing the outline of the configuration of a substrate processing system.

FIG. 2 is a front view of the substrate processing system of FIG.

FIG. 3 is a rear view of the substrate processing system of FIG. 1.

FIG. 4 is an explanatory view of a longitudinal section showing an outline of the configuration of a coating treatment apparatus.

FIG. 5 is an explanatory diagram of a cross section showing an outline of the configuration of a coating treatment apparatus.

FIG. 6 is an explanatory view of a longitudinal section showing an outline of the configuration of the cleaning apparatus.

FIG. 7 is a flowchart showing the main steps of wafer processing.

FIG. 8 is a graph showing a change in the rotation speed of a wafer in a coating process.

FIG. 9 is a schematic diagram showing the state of the wafer in each step of the coating treatment, and (a) is a longitudinal sectional view of the wafer showing a state in which pure water is supplied onto the wafer. (B) is a longitudinal sectional view of a wafer showing a state in which pure water on the wafer is spread. (C) is a longitudinal sectional view of a wafer showing a state in which a resist pattern size reducing agent is supplied to pure water on the wafer. (d) is a longitudinal sectional view of the wafer showing a state in which the resist pattern size reducing agent is spread over the entire surface of the wafer.

FIG. 10 is an enlarged longitudinal sectional view of a wafer coated with a resist pattern dimension reducing agent.

FIG. 11 is an enlarged longitudinal sectional view of a wafer showing a state in which a cured film is formed on a part of the resist pattern dimension reducing agent.

FIG. 12 is an enlarged longitudinal sectional view of a wafer showing a state where an uncured portion of a resist pattern size reducing agent has been removed.

FIG. 13 is an explanatory view of a longitudinal section showing an outline of a configuration of a coating treatment apparatus including a third nozzle that ejects nitrogen gas.

FIG. 14 is a photograph showing the appearance of the outer periphery of the wafer. (A) is a photograph of the resist pattern dimension reducing agent film formed on the outer periphery of the wafer when the drying speed of the resist pattern size reducing agent is slow. It is. (B) is a photograph of the film of the resist pattern size reducing agent formed on the outer periphery of the wafer W when the drying speed of the resist pattern size reducing agent is increased. Explanation of symbols

[0017] 1 substrate processing system

20 Application processing equipment 21 Cleaning equipment

A pure water

B Resist pattern size reducing agent

W wafer

BEST MODE FOR CARRYING OUT THE INVENTION

[0018] Hereinafter, preferred embodiments of the present invention will be described. FIG. 1 is a plan view schematically showing the configuration of a substrate processing system 1 in which the substrate processing method according to the present embodiment is implemented, FIG. 2 is a front view of the substrate processing system 1, and FIG. 2 is a rear view of the substrate processing system 1. FIG.

[0019] As shown in FIG. 1, the substrate processing system 1 carries, for example, a plurality of wafers W in the cassette unit from the outside to the substrate processing system 1, or a wafer C and W from the cassette C. And a processing station 3 having a plurality of processing apparatuses for performing various processes in a series of wafer processing in a single sheet form are integrally connected.

[0020] The cassette station 2 is provided with a cassette mounting table 10. The cassette mounting table 10 is capable of mounting a plurality of cassettes C in a row in the X direction (vertical direction in FIG. 1). The cassette station 2 is provided with a wafer transfer body 12 that can move in the X direction on the transfer path 11. The wafer carrier 12 can also move in the arrangement direction (vertical direction) of the wafers W accommodated in the cassette C, and can selectively access each wafer W in each cassette C arranged in the X direction. .

The wafer carrier 12 can rotate in the Θ direction around the vertical axis, and can also access the extension device 32 belonging to the third processing device group G3 on the processing station 3 side described later.

The processing station 3 is provided with a main transfer device 13 at the center thereof, and various processing devices are arranged in multiple stages around the main transfer device 13 to form a processing device group. Yes. In this substrate processing system 1, four processing device groups Gl, G2, G3, G4 are arranged, and the first and second processing device groups Gl, G2 are arranged on the front side of the substrate processing system 1. The third processing unit group G3 is disposed on the cassette station 2 side of the main transfer unit 13. The fourth processing device group G4 is arranged on the opposite side of the third processing device group G3 across the main transfer device 13. As an option, a fifth processing unit group G5 indicated by a broken line can be separately arranged on the back side. The main transfer device 13 can transfer the wafer W to various processing devices to be described later arranged in these processing device groups G1 to G5.

In the first processing unit group G 1, for example, as shown in FIG. 2, a coating processing unit 20 for applying a predetermined resist pattern size reducing agent on the wafer W and an excess resist pattern size reducing agent are washed. The cleaning device 21 to be removed in this order is arranged in two stages in descending order. Similarly, in the second processing device group G2, the coating processing device 22 and the cleaning device 23 are also stacked in two stages in order of the lower force.

For example, as shown in FIG. 3, the third processing unit group G 3 includes cooling processing units 30 and 31 for cooling the wafer W, an extension unit 32 for waiting the wafer W, and a heat treatment unit 33 for heating the wafer W. 34 etc., the lower force is also stacked in order, for example, in 5 steps.

[0025] In the fourth processing unit group G4, for example, cooling processing units 40 and 41, an extension unit 42, a heating processing unit 43 and 44, and the like are stacked in, for example, five stages in order of the lower force.

The cooling processing apparatuses 30, 31, 40, 41 can cool the wafer W by placing the wafer W on a cooling plate cooled to a predetermined temperature, for example. The heat treatment apparatuses 33, 34, 43, and 44 can heat the wafer W by placing the wafer W on a hot plate heated to a predetermined temperature, for example.

Next, the configuration of the above-described coating treatment apparatuses 20 and 22 will be described. FIG. 4 is an explanatory view of a longitudinal section showing an outline of the configuration of the coating treatment apparatus 20, and FIG. 5 is an explanatory view of a transverse plane of the coating treatment apparatus 20.

The coating treatment apparatus 20 has a casing 70 that can be closed inside, for example. In the center of the casing 70, there is a spin chuck 71 that holds and rotates the Ueno and W! The spin chuck 71 has a horizontal upper surface, and a suction port (not shown) for sucking the wafer W, for example, is provided on the upper surface. The wafer W can be sucked and held on the spin chuck 71 by suction from the suction port.

[0029] The spin chuck 71 can be rotated at a predetermined speed by a chuck drive mechanism 72 including, for example, a motor. The chuck drive mechanism 72 is provided with a lifting drive source such as a cylinder. The spin chuck 71 can move up and down.

[0030] Around the spin chuck 71, there is provided a cup 73 for receiving and collecting the liquid that is scattered or dropped by the wafer W force. A lower surface of the cup 73 is connected to a discharge pipe 74 for discharging the recovered liquid and an exhaust pipe 75 for exhausting the atmosphere in the cup 73. The exhaust pipe 75 is connected to a negative pressure generator 76 such as a pump and can forcibly exhaust the atmosphere in the cup 73.

As shown in FIG. 5, a rail 80 extending along the Y direction (left and right direction in FIG. 5) is formed on the negative side of the cup 73 in the X direction (downward direction in FIG. 5). The rail 80 is formed, for example, to the outer side of the cup 73 in the Y direction negative direction (left direction in FIG. 5) on the Y direction positive direction (right direction in FIG. 5). For example, two arms 81 and 82 are attached to the rail 80.

As shown in FIGS. 4 and 5, the first arm 81 supports a first nozzle 83 for discharging the resist pattern size reducing agent. The first arm 81 is movable on the rail 80 by a nozzle driving unit 84 shown in FIG. 5, and the first nozzle 83 is installed on the outside of the cup 73 on the Y direction positive side. It can be moved from 85 to above the center of the wafer W in the cup 73. Further, the first arm 81 is moved up and down by the nozzle driving unit 84, and the height of the first nozzle 83 can be adjusted.

As shown in FIG. 4, a supply pipe 87 that communicates with a reducing agent supply source 86 is connected to the first nozzle 83. In the present embodiment, for example, the reducing agent supply source 86 includes a resist pattern size reducing agent that is water-soluble, is cured by heat, and becomes insoluble in water, and has resistance to an etching material after the alteration. (RELACS) is stored.

The second arm 82 supports a second nozzle 90 that discharges pure water. The second arm 82 is movable on the rail 80 by, for example, a nozzle driving unit 91 shown in FIG. 5, and the second nozzle 90 is provided outside the cup 73 on the Y direction negative direction side. It can be moved from the standby part 92 to the upper part of the center of the wafer W in the cup 73. Further, the second arm 82 can be moved up and down by the nozzle driving section 91, and the height of the second nozzle 90 can be adjusted. As shown in FIG. 4, a supply pipe 94 communicating with a pure water supply source 93 is connected to the second nozzle 90.

For example, an air supply pipe 100 is connected to the central portion of the ceiling surface of the casing 70. A temperature / humidity adjusting device 101 is connected to the air supply pipe 100. By supplying the gas whose temperature and humidity are adjusted by the temperature and humidity adjusting device 101 into the casing 70, the inside of the casing 70 can be adjusted to an atmosphere of a predetermined temperature and humidity.

[0037] The configuration of the coating treatment apparatus 22 is the same as that of the above-described coating treatment apparatus 20, and a description thereof will be omitted.

Next, the configuration of the cleaning devices 21 and 23 will be described. FIG. 6 is an explanatory view of a longitudinal section showing an outline of the configuration of the cleaning device 21.

The cleaning device 21 includes, for example, a spin chuck 111 that holds and rotates the wafer W in the casing 110. The spin chuck 111 can be rotated at a predetermined speed by the chuck driving mechanism 112. Around the spin chuck 111, there is provided a cup 113 that receives and collects the liquid scattered or dropped from the wafer W. A discharge pipe 114 for discharging the collected liquid is connected to the lower surface of the cup 113.

In the casing 110, a pure water discharge nozzle 120 for discharging pure water is provided. The pure water discharge nozzle 120 is held by an arm 121 that is movable in the horizontal direction, and can move to the upper part of the center of the wafer W in the cup 113 by the standby part 122 force outside the cup 113. The pure water discharge nozzle 120 communicates with a pure water supply source 124 through a supply pipe 123.

[0041] The configuration of the cleaning device 23 is the same as that of the above-described cleaning device 21, and thus the description thereof is omitted.

The wafer processing performed in the substrate processing system 1 is controlled by a control unit 130 provided in the cassette station 2, for example, as shown in FIG. The control unit 130 is a computer, for example, and has a program storage unit. The program storage unit stores a program P for controlling the operation of the drive systems such as the above-described various processing apparatuses and transfer bodies to execute wafer processing of a predetermined recipe described later. The program P may be recorded on a computer-readable recording medium, and the recording medium force may also be installed in the control unit 130. Next, wafer processing performed in the substrate processing system 1 configured as described above will be described. This wafer process is a process for reducing the dimension of the resist pattern by forming a cured film on the inner wall surface of a recess such as a hole or groove of the resist pattern on the wafer W. FIG. 7 is a flowchart showing the main steps of this wafer processing.

First, the wafer W force in the cassette C on the cassette mounting table 10 is taken out by the wafer transfer body 12 and transferred to the extension device 32 of the third processing unit group G3. Thereafter, the Weno and W are transported to the cooling processing device 30 by the main transport device 13, adjusted to a predetermined temperature, and then transported to the coating processing device 20. FIG. 8 shows a change in the rotational speed of the wafer W in the coating process performed by the coating processing apparatus 20. FIG. 9 is a flowchart showing the state of the wafer W in each step of the coating process.

The wafer W transferred to the coating treatment apparatus 20 is first sucked and held by the spin chuck 71 as shown in FIG. Next, the second nozzle 90 moves to above the center of the wafer W. Thereafter, as shown in FIG. 9 (a), a predetermined amount of pure water A is supplied from the second nozzle 90 to the center of the wafer W on which the resist pattern P is formed on the surface (step Sl in FIG. 7). . Thereafter, the wafer W is rotated, for example, at about lOOOOrpm, and the pure water A on the wafer W is spread by centrifugal force as shown in FIG. 9 (b). At this time, the pure water A is not spread over the entire surface of the wafer W, but is spread in a circular puddle shape near the center of the wafer W. The second nozzle 90 that has finished supplying the predetermined amount of pure water A is returned to the standby unit 92.

Next, the first nozzle 83 is moved to above the center of the wafer W. At this time, the rotation speed of the wafer W is lowered to about 30 rpm. With the rotation speed of the wafer W lowered, a predetermined amount of resist pattern size reducing agent B is supplied from the first nozzle 83 onto the pure water A at the center of the wafer W as shown in FIG. 9 (c). The As a result, the resist pattern size reducing agent B is mixed with the pure water A collected near the center of the wafer W. The first nozzle 83 that has finished supplying the resist pattern dimension reducing agent B is returned to the standby unit 85. Thereafter, the rotation speed of the wafer W is increased to about 2000 rpm, for example, and the resist pattern size reducing agent B is spread over the entire surface of the wafer W as shown in FIG. Thus, as shown in FIG. 10, the resist pattern size reducing agent B is applied to the uneven surface of the resist pattern R on the wafer W (step S2 shown in FIG. 7). [0047] Next, the rotational speed of the wafer W is lowered to about lOOrpm. Thereafter, the rotation speed of the wafer W is increased to about 1300 to 1500 rpm as the first rotation speed, and the liquid film of the resist pattern size reducing agent B is adjusted to a predetermined film thickness (step S3 shown in FIG. 7). After the film thickness is adjusted, the rotation speed of the wafer W is further increased to about 3000 rpm, and the resist pattern size reducing agent B is dried (step S4 shown in FIG. 7).

[0048] Thereafter, the rotation of Ueno and W is stopped, and a series of coating processes is completed.

The wafer W that has been subjected to the coating process is then transferred to the heat treatment apparatus 33 and heated.

As shown in FIG. 11, this caloric heat is close to the uneven surface of the resist pattern P! The lower layer portion B 1 of the resist pattern size reducing agent B is cured, and the lower layer portion B 1 becomes insoluble in water. To do. As a result, a cured film of the resist pattern dimension reducing agent B is formed on the inner wall surface of the recess of the resist pattern P (step S5 in FIG. 7).

The wafer W that has been subjected to the heat treatment is transferred to, for example, the cooling processing apparatus 40, and returned to the normal temperature, for example, and then transferred to the cleaning apparatus 21. The wafer W carried into the cleaning device 21 is held by the spin chuck 111 as shown in FIG. Thereafter, the wafer W is rotated by the spin chuck 111 and the pure water as the removal liquid is supplied from the pure water discharge nozzle 120 to the center of the wafer W in the rotated state. As a result, the uncured and water-soluble upper layer portion (portion other than the lower layer portion B1) of the resist pattern size reducing agent B is washed away (step S6 in FIG. 7). Thereafter, the wafer W is rotated at a high speed and dried by shaking. Thus, as shown in FIG. 12, the cured film (lower layer portion B1) having the resist pattern size reducing agent B force is left on the inner wall surface of the recess of the resist pattern P, and the size of the resist pattern P is reduced.

[0051] After that, the wafer W after the cleaning process is returned from the processing station 3 to the cassette C in the cassette station 2 by the main transfer device 13 and the wafer transfer body 12, for example.

[0052] According to the above embodiment, since the resist pattern size reducing agent B is supplied after supplying pure water A onto the wafer W, the wettability of the resist pattern size reducing agent B with respect to the resist pattern P As a result, the resist pattern size reducing agent B is easily spread on the resist pattern P. Therefore, the resist pattern dimension reducing agent B can be applied to the entire surface of the wafer W by supplying a small amount of the resist pattern dimension reducing agent B. As a result, the amount of resist pattern size reducing agent B used can be reduced. Resist pattern dimension reducing agent B is widely used. Resist pattern size reducing agent B can be applied evenly on the wafer surface without unevenness because it is easy to slip.

According to the above embodiment, the wafer W is rotated after the pure water A is supplied onto the wafer W, and the pure water A is circular so as not to spread over the entire surface of the wafer W. Can be spread. Then, the resist pattern dimension reducing agent B is supplied onto the pure water A, the wafer W is further rotated, and the resist pattern dimension reducing agent B is spread over the entire surface of the wafer W. By doing so, pure water A and resist pattern size reducing agent B are properly mixed on Ueno and W, and this mixing reduces the water repellency of resist pattern size reducing agent B to resist pattern P. Dimension reducing agent B spreads properly over the entire surface of wafer W. In addition, resist pattern dimension reducing agent B is supplied to pure water A collected in a circular shape at the center of Ueno and W, and then resist pattern dimension reducing agent B is spread outward at a stretch by centrifugal force. As a result, the resist pattern reducing agent B is uniformly applied on the wafer W surface without any spots.

[0054] After the resist pattern size reducing agent B is spread over the entire surface of the wafer W, the rotational speed of the wafer W is temporarily reduced and then increased to the first rotational speed to increase the film thickness of the resist pattern size reducing agent B. Therefore, when adjusting the film thickness, the resist pattern dimension reducing agent B is always subjected to the inertia in the radial direction of the wafer W, and the resist pattern dimension reducing agent B flows to the outer side of the wafer W. Therefore, the film thickness within the wafer surface is adjusted without unevenness.

[0055] After the resist pattern size reducing agent B is spread over the entire surface of the wafer W, it is not always necessary to temporarily reduce the rotational speed of the wafer W. Immediately after spreading over the entire surface of the wafer, the rotation speed of the wafer W may be adjusted to the first rotation speed.

[0056] By the way, when the drying speed of the spin-coated resist pattern size reducing agent B is slow, a hole-like defect can be formed in the film of the resist pattern size reducing agent B on the outer periphery of the wafer W. It has been confirmed. According to the above embodiment, after adjusting the film thickness of the resist pattern dimension reducing agent B by rotating the wafer W at the first rotation speed, the wafer W is rotated at a high speed at a higher second rotation speed. Since the resist pattern size reducing agent B is dried, the drying speed of the resist pattern size reducing agent B is increased and Thus, the resist pattern dimension reducing agent B film can be properly formed.

In the above embodiment, drying of the resist pattern size reducing agent B is promoted by increasing the rotation speed of the wafer W to the second rotation speed. Let the drying of the resist pattern dimension reducing agent B accelerate by supplying a dry gas.

In such a case, for example, as shown in FIG. 13, the coating processing apparatus 20 is provided with a third nozzle 150 that ejects, for example, nitrogen gas having a low dew point as a dry gas to the outer peripheral portion of the wafer W. . The third nozzle 150 is supported by, for example, a horizontally movable nozzle arm 151 and can move horizontally on the surface of the wafer W in the spin chuck 71. The third nozzle 150 is connected to a nitrogen gas supply source 153 through an air supply pipe 152, for example. Then, the film thickness of the resist pattern dimension reducing agent B on the wafer W is adjusted, and when the resist pattern dimension reducing agent B is dried, the third nozzle 150 moves above the outer periphery of the wafer W, Nitrogen gas is supplied from the third nozzle 150 to the outer periphery of the wafer W rotated. As a result, drying of the resist pattern size reducing agent B on the outer periphery of the wafer W is promoted, and a film having no defect can be formed on the wafer W. Fig. 14 (a) is a photograph of the surface of the film on the outer periphery of the wafer W when the drying speed of the resist pattern size reducing agent B is slow, and Fig. 14 (b) is the resist pattern size reducing agent B as described above. 6 is a photograph of the surface of the film on the outer periphery of the wafer W when the drying speed is increased. In Fig. 14 (a), it can be confirmed that a hole-like defect is formed, and in Fig. 14 (b), the hole-like defect is eliminated.

[0059] Further, at the time of the coating treatment, the humidity is lower than at least the outside of the casing 70 from the air supply pipe 100 into the casing 70, and a dry gas is supplied to reduce the humidity of the ambient atmosphere around the wafer W. Good. For example, when the atmosphere outside the casing 70 is set to a humidity of 45% (temperature 23 ° C), the ambient atmosphere around the wafer W in the casing 70 is set to a humidity of 40% or less (temperature 23 ° C). Even if this is done, drying of the resist pattern dimension reducing agent B is promoted, and a film having no defect is formed. More preferably, the ambient atmosphere around the wafer W is set to a humidity of 40%.

As described above, the preferred embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to such examples. A person skilled in the art will be described in the claims. It is clear that various changes or modifications can be made within the scope of the idea, and it is understood that these also belong to the technical scope of the present invention.

[0061] For example, in the above embodiment, only the wafer processing for reducing the size of the resist pattern is performed in the substrate processing system 1, but the photolithography process for forming the resist pattern is also performed. You may do it. In such a case, in the substrate processing system 1, a processing station 3 is provided with a resist coating processing apparatus that forms a resist film by applying a resist solution to the wafer W, and a development processing apparatus that develops the resist film on the wafer W. An exposure apparatus for exposing the resist film may be provided adjacent to the processing station 3.

In the above embodiment, after the coating process, the lower layer portion B1 of the resist pattern dimension reducing agent B is altered and cured by heating, but it may be altered by light. In the above embodiment, after the coating process, the lower layer portion B1 of the resist pattern size reducing agent B is changed to be insoluble in water and cured, and then the unnecessary upper layer portion is removed with pure water. Later, the lower layer portion B1 of the resist pattern size reducing agent B may be insoluble in the developer, and then the unnecessary upper layer portion may be removed by the developer as a removing solution. In this case, as the resist pattern size reducing agent B, a resist pattern dimensional reducing agent B that is insoluble in a developer by heat or light is used.

The present invention can also be applied to substrate processing when reducing the dimension of a resist pattern formed on an FPD (flat panel display) other than the wafer W, a mask reticle for a photomask, or the like.

Industrial applicability

[0064] The present invention is useful for reducing the amount of a resist pattern size reducing agent used when reducing the size of a resist pattern using the RELACS technology and making the pattern size in the substrate plane uniform. is there.

Claims

The scope of the claims

[1] A substrate processing method for reducing the size of a resist pattern formed on a substrate.

A pure water supplying step of supplying pure water onto the substrate on which the resist pattern is formed, and then supplying a water-soluble resist pattern size reducing agent onto the substrate, rotating the substrate, and applying the resist to the entire surface of the substrate. An application step of applying a pattern size reducing agent; and thereafter, an alteration step of changing the lower layer portion of the resist pattern size reducing agent in contact with the surface of the resist pattern to be insoluble in the removal solution;

And a removal step of removing the unmodified upper layer portion of the resist pattern size reducing agent with a removal liquid.

[2] The substrate processing method according to claim 1!

The pure water supply step includes a step of rotating the substrate to expand the pure water supplied on the substrate to such an extent that it does not spread over the entire surface of the substrate,

In the subsequent coating step, the resist pattern size reducing agent is supplied to the spread pure water, and the resist pattern size reducing agent is spread over the entire surface of the substrate by rotating the substrate.

[3] In the substrate processing method according to claim 2,

After the resist pattern size reducing agent spreads over the entire surface of the substrate in the coating step,

Adjusting the film thickness of the resist pattern size reducing agent by rotating the substrate at a first rotation speed, and then rotating the substrate at a second rotation speed that is faster than the first rotation speed. A step of drying the reducing agent.

[4] In the substrate processing method according to claim 3,

After the resist pattern size reducing agent spreads over the entire surface of the substrate in the coating step, the rotational speed of the substrate is once reduced, and then the substrate is raised to the first rotational speed to increase the resist pattern size reducing agent. Adjust the film thickness.

[5] The substrate processing method according to claim 3, wherein

When drying the resist pattern size reducing agent, dry gas is applied to the outer periphery of the substrate. Supply.

[6] The substrate processing method according to claim 3, wherein

At least when drying the resist pattern size reducing agent, the ambient atmosphere of the substrate is set to a humidity of 40% or less.

[7] A computer-readable storage medium storing a computer program for executing a substrate processing method in a substrate processing system,

The substrate processing method is a substrate processing method for reducing the size of a resist pattern formed on a substrate,

This substrate processing method is: