JPH05315237A - Method for manufacturing semiconductor device - Google Patents

Abstract

(57) [Abstract] [Purpose] In the development process of the photolithography process in the manufacture of semiconductor devices, the precision is improved and the variation is reduced even for a large-diameter wafer. [Structure] Before the wafer to be processed is treated with a developing solution, the wafer 1 is brought into contact with the bubbles 8 of the surfactant 4 so that the surfactant is evenly attached to the entire surface of the wafer. After that, development is performed in a developing tank having a size larger than the diameter of the wafer by bringing the entire surface of the wafer into contact with the developing solution at one time so that there is no time difference in contact with the developing solution within the wafer surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly to a developing method for a photolithographic process during a manufacturing process for a semiconductor device.

[0002]

2. Description of the Related Art Conventionally, as a developing method in a photolithography process in a method of manufacturing a semiconductor device of this type, there has been a method as shown in FIGS. 6 to 10 are schematic diagrams showing the flow of a conventional developing process. First, a wafer to be processed 21 (hereinafter referred to as a wafer to be processed) which is a semiconductor device as an object to be processed is adsorbed and held on a rotatable vacuum chuck 22 (FIG. 6).

The developing solution is dripped onto the wafer 21 to be processed which is stationary or rotating from the developing liquid drop nozzle 23 provided on the vacuum chuck 22 and the wafer 21 to be processed (FIG. 7).

Due to the surface tension of the developing solution 24, the developing solution 24 put on the wafer 21 to be processed develops the wafer 21 to be processed while rotating at about 15 rpm for a predetermined time (FIG. 8). By this rotation, the developer 24
Causes friction with the air and the interface between the air and the wafer to be processed 2
A deviation occurs between the two and circulation occurs, and the developer 24 is agitated.

After the development for a certain period of time, the rotation speed of the vacuum chuck 22 is increased to about 400 rpm, the developing solution is shaken off to stop the development, and then the cleaning water dropping nozzle 25 provided above the wafer 21 to be processed is used. The water 26 is applied to the rotating processing target wafer 21 to wash away the developing solution remaining on the surface of the processing target wafer 21 (FIG. 9).

After sufficient cleaning, the vacuum chuck 2
The rotation speed of 2 is increased to about 4000 rpm, and the water remaining on the surface of the processing target wafer 21 is shaken off and dried.

[0007]

However, in such a developing method, since the time during which the developing solution is in contact differs depending on the position of the surface of the wafer, uneven development occurs concentrically as shown in FIG. It was likely to occur and uniform development could not be performed.

Further, for the purpose of improving the uniformity of development, a method of dropping the developing solution while rotating the wafer to be processed and moving the nozzle under the developing drop in the radial direction from the center of the wafer has been carried out. Was not obtained.

Particularly, in recent years, as device patterns have been miniaturized, even a slight variation in pattern size due to development has been a major factor of reducing the yield.

Further, as the diameter of the wafer increases, the variation in the contact time of the developing solution with the position on the wafer surface increases, which has recently become a new problem.

It is an object of the present invention to provide a method for performing development with high accuracy even on a large diameter wafer.

[0012]

In order to achieve the above-mentioned object, a method of manufacturing a semiconductor device according to the present invention includes a developing process using a developing solution in a developing process of a photoresist in a photolithography process in manufacturing a semiconductor device. Before carrying out, after passing through the step of contacting the entire surface of the wafer to be treated with the bubbles of the surfactant, by using a bath having a width larger than the wafer diameter, only the entire surface of the wafer is simultaneously contacted with the developing solution. The development is performed.

[0013]

The wafer to be processed is brought into contact with the bubbles of the surfactant so that the surface of the wafer to be processed is made compatible with the developing solution while adsorbing the back surface of the wafer to be processed and holding the wafer to be processed. In the same manner as above, the whole surface of the wafer to be processed is developed in a container containing a developing solution having an area and a volume capable of coming into contact with the developing solution at one time, and after the completion of the developing process, the wafer to be processed is washed and dried.

[0014]

The present invention will be described below with reference to the drawings. 1 to 5 are sectional structural views of a developing process showing an embodiment of the present invention.

In FIG. 1, the wafer 1 to be processed has its back surface adsorbed and held by a rotatable vacuum chuck 2. First, in order to make the wafer 1 to be treated accustomed to the developing solution, a treatment is performed in the surfactant tank 3 in order to uniformly and thinly deposit the surfactant on the entire surface of the wafer to be treated.

The surfactant tank 3 is filled with a surfactant 4 therein, and a bubbler 5 for creating fine bubbles is provided therein. The bubbler 5 includes an external pipe 6 and a valve 7 that controls the supply of N ₂ gas for bubble generation.
Through an N ₂ source.

When the valve 7 is opened, small bubbles N ₂ are generated in the surfactant 4 from the bubbler 5, and the bubbles 8 of the surfactant are stored in the surface of the liquid at a thickness of several mm.

The wafer 1 to be processed held by the vacuum chuck 2 has the surface of the wafer 1 facing down and bubbles 8 of the surfactant.
When it descends so as to come into contact with the surface of the wafer, the surfactant is foamed, so that the surfactant is evenly attached to the entire surface of the wafer to be processed.

Next, as shown in FIG. 2, the wafer 1 to be processed is transferred to a shallow developing tank 9 having an area such that the entire surface of the wafer 1 to be processed can be simultaneously contacted with the developer 10, and the wafer surface is brought into contact with the developer 10. Development is performed while rotating the vacuum chuck 2 at about 15 rpm to rotate the wafer 1 to be processed.
Since the developing solution 10 is replaced with a new solution in order to maintain the same developing rate every time one wafer is processed,
The developer tank 9 should have a sufficient amount of liquid for one development. 2
It is shallow so that the depth is about 4 mm.

As shown in FIG. 3, after developing for a predetermined time, the wafer 1 to be processed is pulled up from the developing tank 9 and the vacuum chuck 2 is rotated at about 500 rpm to shake off the developer adhering to the wafer 1 to be processed. Stop development.

As shown in FIG. 4, after that, in order to completely remove the developing solution on the wafer 1 to be processed, the wafer 1 to be processed is transferred to a washing tank 11 and the surface is washed with pure water 12.

As shown in FIG. 5, after the cleaning is performed for a sufficient time, the wafer 1 to be processed is lifted from the water washing tank 11 and 4
The vacuum chuck 2 is rotated at a high speed of about 000 rpm, and pure water on the surface of the wafer 1 to be processed is shaken off and dried.

[0023]

As described above, according to the present invention, the surfactant for accommodating the developing solution to the wafer is bubbled into contact with the wafer before the developing treatment with the developing solution, so that the entire surface of the wafer becomes uneven. Since the surface of the wafer is contacted with the developer all at once using a tank of a size that allows the surface of the wafer to come into contact with the developer at the same time, the difference in the time of contact with the developer on the entire surface of the wafer Is eliminated, and there is an effect that uniform development processing can be performed over the entire surface of the wafer.

In particular, even if the diameter of the wafer becomes larger and larger in the future, the developing method of the present invention can easily maintain the developing accuracy and expect the yield to be improved.

[Brief description of drawings]

FIG. 1 is a process sectional view of a developing process showing an embodiment of the present invention.

FIG. 2 is a process cross-sectional view of a developing process showing an embodiment of the present invention.

FIG. 3 is a process cross-sectional view of a developing process showing an embodiment of the present invention.

FIG. 4 is a process cross-sectional view of a developing process showing an embodiment of the present invention.

FIG. 5 is a process cross-sectional view of a developing process showing an embodiment of the present invention.

FIG. 6 is a process sectional view showing an example of a conventional developing process.

FIG. 7 is a process sectional view showing an example of a conventional developing process.

FIG. 8 is a process sectional view showing an example of a conventional developing process.

FIG. 9 is a process sectional view showing an example of a conventional developing process.

FIG. 10 is a process sectional view showing an example of a conventional developing process.

FIG. 11 is a diagram showing dimensional accuracy in a wafer surface of a wafer processed by a conventional developing process.

[Explanation of symbols]

 1 Wafer to be Processed 2 Vacuum Chuck 3 Surfactant Tank 4 Surfactant 5 Bubbler 6 External Piping 7 Valve 8 Bubbles of Surfactant 9 Developer Tank 10 Developer 11 Washing Tank 12 Pure Water 21 Processed Wafer 22 Vacuum Chuck 23 Development droplet lower nozzle 24 Developer 25 Cleaning droplet lower nozzle 26 Pure water

Claims (1)

[Claims] 1. A process of developing a photoresist during a photolithographic process in the manufacture of a semiconductor device, which comprises a step of bringing the entire surface of a wafer to be processed into contact with bubbles of a surfactant before developing with a developing solution. After that, a method of manufacturing a semiconductor device is characterized in that only a whole surface of the wafer is simultaneously brought into contact with a developing solution for development using a tank having a width larger than the diameter of the wafer.