JPH01302725A - Method for developing photoresist - Google Patents

Abstract

PURPOSE:To make it possible to develop the resist uniformly by a method wherein the developer is sprayed on the resist on a wafer and then is dripped and diffused on the wafer while rotating the wafer. CONSTITUTION:As a pretreatment development, the developer is sprayed from a spray nozzle 14 on a photoresist on a wafer 1 for about 2-5 seconds to turn the photoresist surface from hydrophobic to hydrophilic. Nextly, the developer 5 is dripped from a paddle nozzle 13 on the center of the wafer 1. By rotation of the wafer 1, the developer 5 is diffused on the whole surface of the photoresist. By this method, it is possible to develop the resist uniformly and then to obtain a uniform circuit pattern.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a semiconductor device, and particularly to a method for developing a photoresist.

[Conventional technology]

There are two methods for developing photoresist: paddle development, in which a developing solution is dripped onto the wafer coated with photoresist while the wafer is stationary, and spray development, in which the developing solution is sprayed onto the wafer in a mist. was used to develop photoresist.

In paddle development, as shown in FIG.
In this method, a developer is dripped from the surface of the wafer 1, and the developer 5 is spread over the surface of the wafer 1 to perform development.

Further, spray development is a method of developing the photoresist on the wafer 1 by spraying the developer 5 in the form of a mist from a spray nozzle 44 as shown in FIG.

[Problem to be solved by the invention]

In recent years, as wafer sizes have become larger and higher integration has progressed,
There is a strong demand for reducing variations in circuit dimensions within a wafer. However, the conventional development methods, paddle development and spray development, each have the following drawbacks.

First, in paddle development, the process of uniformly spreading the developer dropped onto the photoresist.

Since the development time differs depending on the distance from the center of the wafer, the dimensions of the photoresist differ especially near the center of the wafer and near the outer periphery.

In addition, in spray development, since the developer is sprayed in the form of a mist, it is difficult to stabilize the chemical change (Te3 decomposition reaction) between the developer and the photoresist over a long period of time. difficult to control.

SUMMARY OF THE INVENTION An object of the present invention is to provide a photoresist developing method that eliminates the above-mentioned drawbacks.

[Differences between the invention and the prior art]

In contrast to the conventional development method described above, the present invention is a development method that combines paddle development and spray development. In particular, spray development is used as a pretreatment to make the photoresist surface hydrophilic, and then paddle development is performed. have differences.

[Means to solve the problem]

In order to achieve the above object, in the photoresist developing method of the present invention, a developer is sprayed onto the photoresist on a wafer in the form of a mist to keep the photoresist surface hydrophilic, and then the developer is applied while rotating the wafer. The developer is dropped onto the photoresist to diffuse it.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

(Example 1) FIGS. 1(a) and 1(b) are schematic diagrams showing a first example of implementing the photoresist developing method of the present invention.

This example is an example in which spray development and paddle development are used in combination.

In the figure, a wafer 1 coated with photoresist is placed on a rotary chuck 2, and a paddle nozzle 13 and a spray nozzle 14 are disposed toward the top surface of the wafer 1.

First, in order to make the hydrophobic photoresist surface hydrophilic, as shown in FIG. Spray for about 2 to 5 seconds. At this time, it is effective to spray while rotating the wafer 1 at 500 rpm to 2000 rpm.

Next, as shown in FIG. 1(b), the paddle nozzle 13
A developer 5 is dropped onto the center of the wafer 1, and the developer 5 is spread over the entire photoresist surface by rotating the wafer 1. The rotation speed of the wafer 1 at this time is preferably in the range of 50 rpm to 20 rpm.

In addition, the developing method of this example is that after the spray @ image is completed, the photoresist surface is washed with pure water (not shown) for about 2 to 10 seconds, and then spin-dried at a rotational speed of about 500 rpm.
Immediately performing puddle development as shown in FIG. 1(b) is extremely effective.

Figure 3(b) shows the case where only paddle development is performed.
c) shows the variation in resist dimensions within a 31φ GaAs square when developed according to this example.

As can be seen from the figure, the maximum dimensional variation (Max-Min) when only paddle development is performed is about 0.2 tm, whereas the maximum dimensional variation (Max-Min) according to this example is approximately 0.2 tm.
-Min) is approximately 0.1- or less.

As mentioned above, by pre-processing with spray development before performing paddle development, the developer dropped from the paddle nozzle 13 can be quickly spread over the photoresist surface, and it is possible to quickly spread the developer solution dropped from the paddle nozzle 13 onto the photoresist surface, and it is possible to spread the developer solution dripped from the paddle nozzle 13 over the photoresist surface. The difference in resist dimensions between and can be reduced.

(Example 2) FIGS. 2(a) and 2(b) are schematic diagrams showing a second example of implementing the photoresist developing method of the present invention.6 In this example, two of the same type of developing means are used. This is an example of using a combination of base addresses.

First, in FIG. 2(a), the photoresist surface on the rotating wafer 1 is developed from two directions from two spray nozzles 24° 24 arranged toward the upper surface of the wafer 1. Spray the liquid.

Next, as shown in FIG. 2(b), while the wafer 1 is being rotated, a developer is dripped onto the photoresist surface from two paddle nozzles 23, 23 placed toward the top surface of the wafer 1. As a result, the developer spreads over the wafer 1 in a short time, and local variations in development time can be reduced.

Although this embodiment shows an example in which two nozzles are used in each case, the number of nozzles is not limited to two. It can handle large wafers in proportion to the number of nozzles used.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to develop the photoresist on the wafer surface in a similar manner, and the variations in the dimensions of the photoresist are reduced, so that a uniform circuit pattern can be obtained.

[Brief explanation of the drawing]

FIGS. 1(a) and (b) are schematic diagrams showing a first embodiment of the present invention, FIGS. 2(a) and (b) are schematic diagrams showing a second embodiment of the present invention, and FIG. Figure 3(a) is a diagram showing an example of the conventional paddle development method, Figure 3(b) is a diagram showing variations in resist dimensions when only the paddle development method is used, and Figure 3(c) is a diagram showing an example of the conventional paddle development method. FIG. 4 is a diagram showing variations in resist dimensions according to examples, and FIG. 4 is a diagram showing an example of a conventional spray development method.

Claims (1)

[Claims] (1) A developer is sprayed onto the photoresist on the wafer in a mist to keep the photoresist surface hydrophilic, and then the developer is dripped while rotating the wafer to diffuse the developer onto the photoresist. A method for developing photoresist.