JP4527037B2 - Substrate development processing method and substrate development processing apparatus - Google Patents

Description

  The present invention provides a substrate for developing a semiconductor wafer, a glass substrate for a liquid crystal display device, a glass substrate for a photomask, a substrate for an optical disk, etc., by supplying a developer to an exposed photoresist film formed on the surface of the substrate. The present invention relates to a development processing method and a development processing apparatus.

  In recent years, in a semiconductor device manufacturing process, high integration has been promoted by miniaturization of pattern dimensions. For example, in the exposure / development process, as a typical means for reducing the processing size of a resist pattern formed on a substrate, resolution is improved by shortening the wavelength of a light beam from an exposure light source. . That is, from the near-ultraviolet ray (wavelength: 400 nm to 300 nm) conventionally used to the use of KrF excimer laser (wavelength: 248 nm), from the KrF excimer laser to use of ArF excimer laser (wavelength: 193 nm), and further to ArF excimer. Technological progress has been made such as the use of radiation with shorter wavelengths such as far ultraviolet rays, X-rays, and electron beams from lasers, and various lithography processes using these exposure light sources have been proposed and put into practical use.

  By the way, the resist corresponding to the shortening of the wavelength of light for exposure has extremely high water repellency. For this reason, in the development processing after exposure, for example, when the developer is deposited on the resist film by the slit scan method, it is difficult to form a liquid film having a uniform thickness as desired. ) Will consume a large amount of developer. Further, when the water repellency of the resist is further increased, it becomes difficult to form the developer film itself.

  As a method for solving such a problem, a process called pre-wet is performed in which pure water is supplied onto the resist film to change the surface state of the resist film to hydrophilic before the developer is deposited. ing. By this treatment, the wettability of the resist film surface to the developer is improved, a developer film having a uniform thickness is formed on the resist film on the substrate surface, and the consumption of the developer can be reduced. However, when the water repellency of the resist is further increased, it becomes difficult to uniformly cover the surface of the resist film even with the pre-wet liquid (pure water) as well as the developer. Consumes a large amount of pure water. Further, if the water repellency of the resist is further increased, it becomes impossible to perform the prewetting process itself.

Therefore, after pattern exposure and before development, a hydrophilizing treatment agent such as tetramethylammonium hydroxide (TMAH), isopropyl alcohol (IPA), diethylethanolamine or the like is used instead of or together with the prewet treatment. A method for improving the wettability of the resist film surface with respect to a developer by performing a hydrophilic treatment on the resist film surface has been proposed (for example, see Patent Document 1).
JP-A-9-106081 (page 2-3, FIG. 1 and FIG. 2)

  However, TMAH is just a developing solution itself, and it is highly likely that TMAH is supplied to the resist film surface before development to adversely affect the processing dimension of the resist pattern. In addition, IPA and diethylethanolamine are organic solvents, which may damage the resist film itself. In addition, when IPA or diethylethanolamine is used, it is necessary to separate and recover from an aqueous solution waste. Therefore, there is a problem that the configuration of the development processing apparatus becomes complicated.

  The present invention has been made in view of the above circumstances, and improves the wettability of the resist film surface with respect to the developer without adversely affecting the processing dimension of the resist pattern or damaging the resist film. It is an object of the present invention to provide a substrate development processing method that can be carried out and that does not require the separation and recovery of waste liquid, and to provide a substrate development processing apparatus that can suitably implement the method.

  According to a first aspect of the present invention, in the method for developing a substrate, the developing solution is supplied onto the resist film by supplying the developing solution onto the exposed resist film formed on the surface of the substrate to develop the resist film. A step of supplying a solution containing a surfactant onto the resist film, and a step of further supplying pure water onto the resist film to which a solution containing a surfactant has been supplied in this step. It is characterized by.

  According to a second aspect of the present invention, there is provided a substrate holding means for holding the substrate in a horizontal posture, and a developer supply for supplying the developer onto the resist film after exposure formed on the surface of the substrate held by the substrate holding means. In a substrate development processing apparatus comprising: a solution supplying means for supplying a solution containing a surfactant onto a resist film formed on the substrate surface; and supplying pure water onto the resist film formed on the substrate surface And a pure water supply means that includes a surfactant on the resist film on the substrate surface by the solution supply means before supplying the developer onto the resist film on the substrate surface by the developer supply means. A solution is supplied, and then pure water is supplied onto the resist film on the substrate surface by the pure water supply means.

  According to a third aspect of the present invention, in the development processing apparatus according to the second aspect of the present invention, the development processing apparatus further includes a substrate rotating unit that rotates the substrate held by the substrate holding unit.

According to the development processing method of the invention of claim 1, even when the water repellency of the resist film is high, a solution containing a surfactant is supplied onto the resist film before supplying the developer onto the resist film. In addition, the wettability of the resist film surface with respect to pure water or developer is improved. Therefore, a pre-wet treatment with pure water is possible, and the surface of the resist film can be uniformly covered with pure water by the pre-wet treatment, and the consumption of pure water can be reduced. In addition, when the developer is supplied onto the resist film after the pre-wet treatment, a developer film having a uniform thickness can be formed on the resist film on the substrate surface, and the consumption of the developer can be reduced. Can do. In addition, since no hydrophilizing agent such as TMAH, IPA, diethylethanolamine or the like is used, there is no fear of adversely affecting the processing size of the resist pattern or damaging the resist film, and the apparatus configuration may be complicated. Absent.
Further, since pure water is further supplied onto the resist film supplied with the solution containing the surfactant and the pre-wetting treatment is performed, the solution containing the surfactant is washed out with pure water from the resist film. As a result, for example, components in the surfactant such as fluorine or silicon that do not dissolve in the developer are removed from the resist film, so that there is no fear of defects in the resist film.

  When the development processing apparatus of the invention according to claim 2 is used, the development processing method of the invention of claim 1 can be suitably implemented, and the above-described effects can be obtained.

  In the development processing apparatus of the invention according to claim 3, by supplying a solution containing a surfactant onto the resist film formed on the substrate surface, the substrate held by the substrate holding means is rotated by the substrate rotating means. The excess surfactant solution can be removed from the resist film by centrifugal force, and after supplying pure water onto the resist film, the substrate held by the substrate holding means is rotated by the substrate rotating means. Thus, excess pure water can be removed from the resist film by centrifugal force. Therefore, a surfactant solution film or pure water film having a desired thickness can be formed on the resist film, and uniform processing can be performed.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.
1 to 3 show an example of a configuration of a development processing apparatus used for carrying out a substrate development processing method according to the present invention, and FIG. 1 is a plan view showing a schematic configuration of the development processing apparatus. 2 is a cross-sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line III-III in FIG.

  This development processing apparatus includes a spin chuck 10 that holds the substrate W in a horizontal position at the center of the apparatus where the development processing of the substrate W is performed, and a rotary support shaft 12 that is vertically supported with the spin chuck 10 fixed to the upper end. In addition, a rotary motor 14 that rotates the spin chuck 10 and the rotary support shaft 12 around a vertical axis is provided. A circular inner cup 16 is disposed around the spin chuck 10 so as to surround the substrate W on the spin chuck 10, and the inner cup 16 is supported by a support mechanism (not shown) so as to be reciprocally movable in the vertical direction. ing. A rectangular outer cup 18 is disposed around the inner cup 16.

  Standby pots 20 and 22 are disposed on the left and right sides of the outer cup 18, respectively. A guide rail 24 is disposed on one side of the outer cup 18 and the standby pots 20 and 22 in parallel with the connecting direction of the outer cup 18 and the standby pots 20 and 22. An arm driving unit 26 is slidably engaged with the guide rail 24, and a nozzle arm 28 is held by the arm driving unit 26. A developer discharge nozzle 30 is suspended from the nozzle arm 28 in a horizontal posture. Although the detailed illustration of the developer discharge nozzle 30 is omitted, the developer discharge nozzle 30 has a slit-like discharge port extending in the longitudinal direction on the lower end surface. A developer supply pipe (not shown) connected to the developer supply source in a flow path is connected to the developer discharge nozzle 30 in communication. The developer discharge nozzle 30 is arranged in a direction orthogonal to the guide rail 24. Then, the arm drive unit 26 linearly reciprocates the nozzle arm 28 along the guide rail 24 in the horizontal direction, scans the developer discharge nozzle 30 in the direction indicated by the arrow A, and returns to the opposite direction. It has a configuration that can.

  Further, near the rear side of the outer cup 18, a pure water discharge nozzle 32 that discharges pure water onto the substrate W from the discharge port at the front end, and a solution containing a surfactant from the discharge port at the front end onto the substrate W. A solution discharge nozzle 34 for discharging is disposed. The pure water discharge nozzle 32 is connected to a pure water supply source through a pure water supply pipe (not shown), and the solution discharge nozzle 34 is connected to a surfactant solution supply source through a solution supply pipe (not shown). Yes. The pure water discharge nozzle 32 and the solution discharge nozzle 34 are held by a single nozzle holding unit 38 that is rotatably supported by the rotation drive unit 36. Then, by rotating the nozzle holding portion 38 around the vertical axis by the rotation driving portion 36, the pure water discharge nozzle 32 and the solution discharge nozzle 34 are rotated in the horizontal plane in the direction indicated by the arrow B. ing.

  Next, an example of processing operation by the development processing apparatus having the above-described configuration will be described.

  When the substrate W having the exposed resist film formed on the surface is carried into the apparatus and the substrate W is held by the spin chuck 10, the solution discharge nozzle 34 (and the pure water discharge nozzle 32) is rotated. The tip discharge port of the solution discharge nozzle 34 moves to a position directly above the center of the substrate W, and a predetermined amount of a solution containing a surfactant adjusted to a predetermined concentration from the tip discharge port of the solution discharge nozzle 34 is centered on the substrate W. Supplied dropwise. The kind of surfactant used here is not specifically limited, What is necessary is just to use a general anionic surfactant and a cationic surfactant. The surfactant solution supplied onto the substrate W spreads over the entire surface of the substrate W and covers the entire surface of the resist film on the substrate W. At this time, the substrate W may be rotated at a low speed. The solution discharge nozzle 34 (and the pure water discharge nozzle 32) is rotated back to the original position shown in FIG. 1 after the discharge of the surfactant solution. After a predetermined time has elapsed since the surfactant solution was discharged, the substrate W is rotated, and excess surfactant solution is scattered from the substrate W by centrifugal force to be removed. At this time, the inner cup 16 is raised.

  Next, the pure water discharge nozzle 32 (and the solution discharge nozzle 34) is rotated to move the front end discharge port of the pure water discharge nozzle 32 to a position directly above the center of the substrate W. A predetermined amount of pure water is supplied from the outlet to the center of the substrate W. The pure water supplied onto the substrate W spreads over the entire surface of the substrate W, and the surfactant solution is washed away from the resist film, so that the surfactant solution covering the resist film surface is replaced with pure water. At this time, the substrate W may be rotated at a low speed. After a predetermined time has elapsed since the pure water was discharged, the substrate W is rotated, and the pure water is scattered and removed from the substrate W by centrifugal force. At this time, the inner cup 16 is raised. In this way, the pre-wetting process of the resist film is performed. The pure water discharge nozzle 32 (and the solution discharge nozzle 34) is rotated back to the original position shown in FIG.

  Subsequently, the developer driving nozzle 30 is scanned in the direction indicated by the arrow A by the arm driving unit 26 while discharging the developing solution from the slit-like discharge port of the developing solution discharge nozzle 30. As a result, the developer is supplied onto the substrate W and accumulated. When the developer discharge nozzle 30 moves to the position of the standby pot 22 on the right side, the discharge of the developer is stopped, and the arm drive unit 26 moves the developer discharge nozzle 30 in the direction opposite to the direction indicated by the arrow A to develop. The liquid discharge nozzle 30 is returned to the original left standby pot 20 position. Then, the resist film on the surface of the substrate W is developed by keeping the substrate W stationary until a predetermined time elapses after the liquid is deposited on the substrate W.

  When a predetermined time elapses after the liquid is deposited on the substrate W, the pure water discharge nozzle 32 (and the solution discharge nozzle 34) is rotated again so that the tip discharge port of the pure water discharge nozzle 32 is directly above the center of the substrate W. The pure water is supplied to the central portion of the substrate W from the tip discharge port of the pure water discharge nozzle 32. Thereby, the development reaction of the resist film on the surface of the substrate W is stopped. The pure water discharge nozzle 32 (and the solution discharge nozzle 34) is rotated back to the original position shown in FIG. Then, after the pure water is discharged, the substrate W is rotated, the pure water is scattered and removed from the substrate W by centrifugal force, and the substrate W is dried. At this time, the inner cup 16 is raised. When the drying process of the substrate W is completed, the substrate W is removed from the spin chuck 10 and carried out of the apparatus.

  In the development processing method according to the present invention, as described above, a solution containing a surfactant is supplied onto the resist film before supplying the developer onto the resist film formed on the surface of the substrate W. For this reason, even if the water repellency of the resist film is high, the surface of the resist film is covered with the surfactant solution film, and the wettability of the resist film surface with respect to pure water or developer is improved. As a result, the subsequent pre-wet treatment with pure water is possible, and the pre-wet treatment can uniformly cover the surface of the resist film with pure water, and can reduce the consumption of pure water. it can. In addition, when the developer is supplied onto the resist film after the pre-wet treatment with pure water, a developer film having a uniform thickness can be formed on the resist film on the substrate surface, and the consumption of the developer is also reduced. Can be reduced. Then, after the surfactant solution is supplied onto the resist film on the surface of the substrate W and before the developer is supplied onto the resist film, pure water is supplied onto the resist film and pre-wet processing is performed. The surfactant solution is washed away from the resist film with pure water. As a result, for example, components in the surfactant such as fluorine and silicon that do not dissolve in the developer are removed from the resist film, so that there is no risk of defects in the resist film.

  In the above-described embodiment, a slit scanning method in which the developer discharge nozzle 30 is scanned while discharging the developer from the slit-like discharge port of the developer discharge nozzle 30 to deposit the developer on the resist film on the substrate surface. As described above, the development processing method is not particularly limited, and a developing method in which a developing solution is supplied from a straight nozzle to the center of the surface of the substrate and rotated to spread the developing solution over the entire surface of the substrate, while rotating the substrate. The present invention can also be widely applied to a developing method in which a developer is ejected from a spray nozzle onto a resist film on a substrate surface. In the above embodiment, a solution containing a surfactant or pure water for pre-wetting is supplied from a straight nozzle onto the resist film on the substrate surface. The surfactant solution or pure water may be discharged onto the resist film from a nozzle having a slit-like discharge port or a spray nozzle. Further, the amount of the surfactant solution or pure water (pre-wet liquid) used, the amount remaining on the resist film, and the like are not particularly limited.

1 is a schematic plan view showing an example of the configuration of a development processing apparatus used for carrying out a substrate development processing method according to the present invention. It is II-II arrow sectional drawing of FIG. FIG. 3 is a cross-sectional view taken along the line III-III in FIG. 1.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Spin chuck 12 Rotation spindle 14 Rotation motor 16 Inner cup 18 Outer cup 20, 22 Standby pot 24 Guide rail 26 Arm drive part 28 Nozzle arm 30 Developer discharge nozzle 32 Pure water discharge nozzle 34 Solution discharge nozzle 36 Rotation drive part 38 Nozzle holding part W substrate

Claims (3)

In the development processing method for a substrate in which a developing solution is supplied onto the resist film after exposure formed on the surface of the substrate to develop the resist film.
Supplying a solution containing a surfactant onto the resist film before supplying the developer onto the resist film;
A step of supplying pure water onto the resist film to which a solution containing a surfactant is supplied by this step;
A method for developing a substrate, comprising: Substrate holding means for holding the substrate in a horizontal position;
A developer supply means for supplying a developer onto the resist film after exposure formed on the surface of the substrate held by the substrate holding means;
In a substrate development processing apparatus comprising:
Solution supply means for supplying a solution containing a surfactant onto the resist film formed on the substrate surface;
Pure water supply means for supplying pure water onto the resist film formed on the substrate surface;
Before supplying the developer onto the resist film on the substrate surface by the developer supplying means, and supplying a solution containing a surfactant onto the resist film on the substrate surface by the solution supplying means. And a pure water supply unit for supplying pure water onto the resist film on the substrate surface. The substrate development processing apparatus according to claim 2, further comprising a substrate rotating unit that rotates the substrate held by the substrate holding unit.

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