JPS62229837A - Method and device for devloping resist - Google Patents

Abstract

PURPOSE:To make equal the developing speed in the central part of a semiconductor wafer with that in the peripheral parts and to eliminate the dimensional difference of a resist pattern by a method wherein a nozzle which is made to jet a developing soultion on the semiconductor wafer, is rotated. CONSTITUTION:A chuck 12 is maintained in a stopped state without being rotated and while a motor 15 is driven and a nozzle 13 is rotated, a developing solution is jetted on a semiconductor wafer 10 through the nozzle 13. in this case, as the main body 13a of the nozzle bas a length equal or more with the diameter of the semiconductor wafer 10, the developing solution is sprayed on the whole surface of the semiconductor wafer 10 by the rotation of the nozzle 13. As the semiconductor wafer 10 is not rotated during the developing, no centrifugal force does not act on the developing solution and the developing solution pervades uniformly the whole surface of the semiconductor wafer 10. Accordingly, there is no dlfference between the amounts of the developing solution in the central part and peripheral parts of the semiconductor wafer 10 and the dimensions of a resist pattern in the central part and peripheral parts become uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION (Object of the Invention) (Industrial Application Field) The present invention relates to a resist developing method and apparatus for developing a resistor coated on a semiconductor wafer in order to form an integrated circuit on the semiconductor wafer.

(Prior Art) In the manufacture of semiconductor devices, a photoetching process is an important process for forming integrated circuits.

The development of the photoresist in this photoetching step is carried out using a spray type developing device as shown in FIG. A chuck 1 that supports a semiconductor wafer 5 by suction is attached to a rotating shaft 2, so that the semiconductor wafer 5 is rotated. Above the chuck 1, a nozzle 3 for spraying a developer onto the semiconductor device 5 is supported and fixed on a support bracket 4. In this case, the developer jetted from the nozzle 3
The nozzle 3 is attached so that it can cover a distance equal to the radius from the center of the semiconductor wafer 5 supported by the nozzle 3.

A first method of developing photoresist l- using such a resist developing apparatus will be described. First, a resist is uniformly applied to a semiconductor wafer, and the semiconductor wafer is heated to volatilize the solvent in the resist. Next, after exposure using a stepper, the semiconductor wafer 5 is transferred onto the chuck 1, and the chuck 1 is centered by performing centering, and the semiconductor wafer 5 is attracted to the chuck 1. On the other hand, the nozzle 3 is arranged so that the developer from the nozzle 3 is sprayed at a predetermined position on the semiconductor wafer 5 at a constant angle.
Adjust. After completing the setting in this way, the developer is injected from the nozzle 3. At this time, the rotating shaft 2 is rotated forward, thereby causing the semiconductor wafer 5 to rotate at a constant speed, and the injection is performed.

In this method, the developer is spread over the entire surface of the semiconductor wafer by centrifugal force, and the photoresist is developed over the entire surface of the semiconductor wafer. After development, a cleaning liquid is sprayed from a cleaning nozzle (not shown) for rinsing, and the semiconductor wafer is dried while avoiding high-speed rotation.

In contrast to such a developing method, the second developing method is to inject a developer from the nozzle 3 while rotating the semiconductor wafer 5 at a low speed to fill the upper surface of the semiconductor wafer 5 with the developer. Since the developer is held on the semiconductor wafer by surface tension, the developer moves forward.

During development, the semiconductor wafer is rotated at high speed to be scattered and the developer is injected from the nozzle 3 in order to replace the developer with a new developer.

However, in these development methods, there is a problem that the photoresist formed by development differs between the central portion and the peripheral portion of the semiconductor wafer. FIG. 6 is a plot of the dimensions of photoresist 1 to pattern against the distance from the center of the semiconductor wafer.
The dimensions of the periphery are larger. This dimensional difference is generally 0.2 to 0.4 μm, which results in defective products in integrated circuit devices that require strict control of circuit patterns.
This has become a major problem. This is because the semiconductor wafer rotates during or during the transfer, and the developer moves from the center to the periphery due to centrifugal force.

Furthermore, in addition to these problems, the method of spraying the developer while rotating the wafer increases the replacement rate of the developer, and the cross-sectional shape of the resist that should be as shown in FIG. There was a problem that the shape was unstable as shown in A>.

(Problems to be Solved by the Invention) As described above, in the conventional method, since the semiconductor wafer rotates, the dimensions of the resist pattern become nonuniform, and the cross-sectional shape of the resist also deforms. This is because the centrifugal force generated by the rotation of the semiconductor wafer acts on the developer.

The present invention was made in response to these problems.
It is an object of the present invention to provide a resist developing method and apparatus that make it possible to form a resist pattern with uniform dimensions and to make the cross-sectional shape of the resist uniform.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, the present invention is characterized in that a nozzle that injects a developer onto the semiconductor wafer is rotated so that the semiconductor wafer is fixed or rotated at a low speed. .

(Function) With the above configuration, the developer injected onto the semiconductor wafer is spread over the semiconductor wafer with a uniform thickness without moving on the semiconductor wafer, and the development speed in the center portion and the peripheral portion becomes equal. This eliminates dimensional differences in resist patterns.

(Example) Hereinafter, the present invention will be described in more detail with reference to Examples.

FIG. 1 is a perspective view of a resist developing device according to an embodiment of the present invention. A chuck 12 is attached to the rotating shaft 11 to support the semiconductor device-C 10 by suction.
A nozzle 13 for spraying a developer onto the semiconductor wafer 10 is provided above the chuck 12 . The nozzle 13 consists of a pipe-shaped main body 13a and a connecting pipe 13b for supplying the developer to the main body 13a, and the connecting pipe 13b is connected to a pressure feeding means such as a pump or a compressor (not shown). As shown in FIG.
3c is formed in the longitudinal direction.

The main body portion 13a is approximately equal to or longer than the diameter of the semiconductor wafer 10, and is provided above the chuck 12 so as to coincide with the diameter line of the semiconductor wafer 10. This nozzle 13 has a gear 1.
4 is attached, and this gear 14 is attached to the shaft of the motor 15 and meshes with the gear 16 which is attached to the shaft of the motor 15. Therefore, when the motor 15 is driven, its rotational force is transmitted to the nozzle 13 via the gear 14 and 16, and the nozzle 1
3 has a structure that rotates on the semiconductor wafer 10. Note that a cleaning nozzle 17 for spraying cleaning liquid onto the semiconductor wafer 10 is provided obliquely above the chuck 12.

Next, a method for developing a resist on a semiconductor wafer using the above-described apparatus will be described. For example, a semiconductor wafer coated with positive photoresist and with the solvent evaporated is exposed using a stepper. Next, this semiconductor wafer is vacuum-adsorbed onto the chuck 12 and developed. During this development, the developer 12 is maintained in a stopped state without rotating, and the developing solution is injected from the nozzle 13 onto the semiconductor wafer 10 while the motor 15 is driven to rotate the nozzle 13. In this case, since the main body 13a of the nozzle has a length equal to or longer than the diameter of the semiconductor wafer 10, the developer is sprayed over the entire surface of the semiconductor wafer 10 by the rotation of the nozzle 13. The spraying of the developing blood is carried out for, for example, 30 seconds, during which time the resist is developed. After development, while rotating the semiconductor wafer 10, the cleaning solution is discharged from the cleaning nozzle 17 to remove the developer.

According to such a method, the semiconductor layer 810 is removed during development.
Since the developer is not rotated, no centrifugal force is applied to the developer, and the developer is uniformly distributed over the entire surface of the semiconductor wafer 10. Therefore, there is no difference in the amount of developer between the center and the periphery of the semiconductor wafer 10, and the dimensions of the resist pattern at the center and the periphery become uniform. FIG. 3 is a characteristic diagram obtained by measuring the dimensions of a resist pattern developed by the above-described method, and the dimensions of the resist pattern in the central portion of the semiconductor wafer and the resist pattern in the peripheral portion are approximately equal. Further, when the semiconductor wafer 10 is developed in a stationary state, no flow of current blood occurs, so that the new surface shape of the resist is also normalized as shown in FIG. 7(B).

When performing paddle development, spray the developer for about 3 seconds while rotating the nozzle with the nozzle stopped rotating onto the semiconductor wafer, stop spraying the developer for 10 seconds, and then
After 0 seconds, the developer is sprayed for 3 seconds, and thereafter, the same procedure is repeated.

Further, according to j3 of the present invention, it is sufficient that the developer is uniformly spread over the semiconductor wafer, and under the condition that this state is maintained, the development may be performed while rotating the semiconductor wafer at a low speed.

FIGS. 4A and 4B are perspective views of other embodiments of the nozzle used in the present invention. In the same figure (A>), a nozzle 13 is formed on a conical cylinder, and a number of ejection holes are formed on the bottom surface. , the developer is sprayed over the entire surface of the semiconductor wafer. Also, as shown in FIG. By spraying, it is possible to form a developer layer with a uniform thickness on the entire surface of the semiconductor unit.The rotation mechanism for this rotation uses other drive sources such as a cylinder, rack and pinion. can do.

(Effects of the Invention) As described above, according to the present invention, since development is performed while rotating the nozzle that injects the developer, the developer is uniformly distributed over the entire surface of the semiconductor wafer, and the developer is uniformly sized. It becomes possible to form a resist pattern, and the cross-sectional shape of the resist also becomes good.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a resist developing device according to an embodiment of the present invention, FIG. 2 is a side view of its nozzle, and FIG. 3 is a graph showing dimensions of a resist pattern formed by a resist developing method according to the present invention. 4(A) and 4(B) are perspective views, not showing other embodiments, of nozzles used in the resist developing device according to the present invention, FIG. 5 is a perspective view of a conventional resist developing device, and FIG. Conventional resist] - Characteristic diagram showing the dimensions of a pattern on the resist 1 formed by the developing method. Figures 57 (A) and (B) are diagrams showing the cross-sectional shape of the resist pattern. 10... Semiconductor wafer, 12... Chuck, 13
...Nozzle, 14.15.16...Rotation mechanism.

Claims (1)

[Scope of Claims] 1. A resist development method in which development is performed by spraying a developer from a nozzle onto a resist coated on a semiconductor wafer and exposed to light, characterized in that the developer is sprayed while rotating the nozzle. resist development method. 2. A resist developing method according to claim 1, characterized in that the developer is sprayed while the semiconductor wafer is not rotating. 3. A resist developing method according to claim 1, characterized in that the semiconductor wafer is rotated at a slower speed than the rotation of the nozzle to spray the developer. 4. A resist developing device comprising a chuck for supporting a semiconductor wafer, a nozzle provided above the chuck for spraying a developer onto the semiconductor wafer, and a rotation mechanism for rotating the nozzle.