JPH081886B2 - Resist discharge nozzle - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a resist discharge nozzle mounted in a resist coating apparatus for coating a surface of an object to be treated with a resist.

(Prior Art) Generally, in an apparatus for applying a resist to an object to be processed, a resist discharge nozzle for dropping a predetermined amount of resist on the surface of the object to be processed is provided.

FIG. 4 shows, as an example of such a conventional resist discharge nozzle, a resist discharge nozzle provided in a developing device or the like for coating a resist on a semiconductor wafer and developing the resist. The nozzle body 1 is, for example, SUS316. This is a tube made of stainless steel, PTFE, etc., with an outer diameter of 3 mm and an inner diameter of 2 mm,
The length is, for example, about 500 mm.

The nozzle body 1 is connected to the resist supply unit 3 by a resist supply pipe 2, and, for example, a novolac photoresist is supplied from the resist supply unit 3 by a predetermined amount, for example, 3 to 5 cc for a 6-inch wafer. Tube 2
It is discharged from the tip of the nozzle body 1 through the inside.

On the other hand, below the nozzle body 1, a rotary table 5 on which the semiconductor wafer 4 is placed is arranged so as to face the nozzle body 1, and the resist dropped on the semiconductor wafer 4 rotates the rotary table 5 (for example, 1000 rpm). ), It is uniformly dispersed on the surface of the semiconductor wafer.

(Problems to be Solved by the Invention) However, in the above-described conventional resist discharge nozzle, the resist is left on the resist discharge port, that is, the nozzle tip surface 1a after the resist is dropped due to its surface tension. As a result, there is a problem in that resist coating unevenness occurs during the next wafer processing.

That is, the resist 6 remaining on the surface 1a of the nozzle tip portion is gradually dried. For example, in the case of a novolac photoresist, the viscosity of 20 cp to 100 cp normally increases to about 500 cp due to drying. Then, at the time of the next work, the highly viscous resist is mixed into the resist droplets, so that the viscosity distribution in the resist droplets becomes nonuniform, so that the resist is not uniformly dispersed on the surface of the semiconductor wafer, Will cause uneven coating.

In addition, there is a problem that dust remains on the remaining resist 6 and adheres to the semiconductor wafer 4 to reduce the yield.

The present invention has been made to solve the above-described problems, and provides a resist discharge nozzle capable of reducing the resist coating unevenness and further improving the yield by reducing the residual amount of the resist on the nozzle tip surface. The purpose is to do.

[Structure of the Invention] (Means for Solving Problems) A resist discharge nozzle according to the present invention has a discharge port at the tip of a tubular body, and discharges a resist solution from a discharge port onto a target object. In the nozzle, the thickness of the surface of the tube tip portion is configured to be thinner than the thickness of other portions, and at least the inner diameter of the tip portion of the nozzle is made thinner than the inner diameter of other portions. It is a thing.

(Operation) By reducing the wall thickness of the tip portion of the resist discharge nozzle and making the inner diameter of at least the tip portion of the nozzle smaller than the inner diameter of other portions, the resist remaining on the tip portion is reduced. In addition, it is possible to prevent uneven application of the resist, and since the amount of the resist remaining on the surface of the nozzle tip portion is small, it is possible to prevent the yield from being reduced due to the dust adhering to the residual resist.

(Example) Hereinafter, one example of the present invention will be described with reference to the drawings. First, for comparison, the configuration of a conventional resist discharge nozzle will be described in detail with reference to FIG.

The nozzle body 7 is a stepped thin cylindrical tube having a thin outer diameter at its tip, for example, stainless steel such as SUS316 or PT.
It is made of FE or the like and has a length of 500 mm, for example, the outer diameter of the thick tube portion 7a is 3 mm, the outer diameter of the thin tube portion 7b is 2.5 mm, the inner diameter is 1.5 mm, and the length of the thin tube portion 7b is, for example, 10 mm. There is.

Further, the resist discharge port, that is, the nozzle tip surface 7c is formed as a smooth surface in order to reduce the amount of resist adhered.

By reducing the thickness of the nozzle tip surface 7c in this manner, the amount of resist remaining on the nozzle tip surface 7c after resist discharge is reduced, so that in the next operation, the high-viscosity resist in the resist droplets The amount of mixture can be reduced. Therefore, since the viscosity distribution in the resist droplets can be kept constant, the dispersion of the resist on the semiconductor wafer becomes uniform and the uneven coating of the resist can be reduced.

Further, since the amount of resist remaining on the nozzle tip surface 7c is small, it is possible to prevent a decrease in yield due to dust attached to the residual resist.

As another conventional example, as shown in FIG. 3, there is a nozzle body 7 in which a stepped portion 7d of a thick pipe portion 7a and a thin pipe portion 7b is formed in a tapered shape. If the stepped portion 7d is tapered like this, workability at the time of manufacturing the nozzle is improved,
Furthermore, the bending strength of the stepped portion 7d can be increased.

Then, as shown in FIG. 1, in the embodiment of the present invention,
By forming the nozzle body 7 in a tapered shape toward the tip, the wall thickness of the tip surface of the nozzle body 7 is configured to be thinner than that of other portions, and not only the outer diameter but also the inner diameter is formed. ,
The tip of the nozzle body 7 is configured to be thinner than other portions. In this case, the tip may be shaped like a knife edge.

As described above, in the present invention, the wall thickness of the nozzle tip is thin,
In addition, since the inner diameter of the tip of the nozzle is smaller than the inner diameter of the other portion, the residual flow rate of the resist at the nozzle tip is smaller than that of the conventional example described above, and the residual liquid remains in the resist droplets in the next work. Mixing of the resist is reduced, and uneven coating of the resist can be prevented. Further, since the resist remaining on the surface of the nozzle tip portion is small, it is possible to prevent the yield from being reduced due to the dust adhering to the residual resist.

Any shape may be used as long as the wall thickness between the outer diameter and the inner diameter on the surface of the nozzle tip portion is thin and the inner diameter of the tip portion is thinner than the other portions. Further, if the surface of the nozzle tip portion is made smooth, the resist is less likely to adhere, which is more effective.

[Effects of the Invention] As described above, according to the resist discharge nozzle of the present invention, the wall thickness of the nozzle tip portion is thin, and the inner diameter of at least the tip portion of the nozzle is smaller than the inner diameters of other portions. Therefore, the residual flow rate of the resist at the tip of the nozzle is reduced, mixing of the residual resist into the resist droplets in the next work is reduced, and uneven coating of the resist can be prevented.

Further, since the resist remaining on the surface of the nozzle tip portion is small, it is possible to prevent the yield from being reduced due to the dust adhering to the residual resist.

[Brief description of drawings]

FIG. 1 is a partial sectional view showing a resist discharging nozzle of an embodiment according to the present invention, FIG. 2 is a partial sectional view showing a conventional resist discharging nozzle, and FIG. 3 is a partial sectional view showing a conventional resist discharging nozzle. 4 and 5 are partial cross-sectional views showing a conventional resist discharge nozzle. 7 ... Nozzle body, 7a ... Thick tube part, 7b ... Thin tube part, 7c ...
… Nozzle tip surface, 7d… Tapered part.

Claims (4)

[Claims] 1. A resist discharge nozzle which has a discharge port at the tip of a tubular body and discharges a resist solution from the discharge port to an object to be processed. A resist discharge nozzle characterized in that it is thinner than the thickness and at least the inner diameter of the tip portion of the nozzle is smaller than the inner diameters of other portions. 2. The resist discharge nozzle according to claim 1, wherein the surface of the tube tip portion is formed into a smooth surface. 3. The resist discharge nozzle according to claim 1, wherein the tip of the nozzle is formed in a knife-edge shape. 4. The resist discharge nozzle according to claim 2, wherein the outer diameter of the tip portion of the nozzle is smaller than the outer diameter of other portions.