JPH051971B2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a photoresist coating machine.

[Conventional technology]

Conventionally, when spin-coating a photoresist onto a semiconductor wafer (hereinafter simply referred to as a wafer), the temperature of the photoresist, the temperature of the atmosphere inside and outside the cup, and the temperature of the wafer chuck that holds the wafer are unstable due to the influence of the surrounding environment. Ta. For this reason, the film thickness of the photoresist spin-coated onto the wafer becomes unstable and often differs from the desired film thickness value. Furthermore, the film thickness was measured using a separate film thickness measuring device.

[Problem that the invention seeks to solve]

As described above, in the conventional photoresist coating method using a coating machine, the actual photoresist coating thickness often differs from the desired coating thickness because there are temperature differences between the photoresist, the atmosphere inside and outside the cup, and the wafer chuck. Therefore, there is a problem in that the film thickness of the photoresist after spin coating varies greatly from wafer to wafer and from lot to lot, reducing the manufacturing yield and reliability of semiconductor devices.

Furthermore, since the film thickness of the photoresist was measured using a separate film thickness measuring device, there was also the problem that the work was complicated and required a lot of work time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a photoresist coating machine that can reduce working time and improve manufacturing yield and reliability of semiconductor devices.

[Means for solving problems]

The photoresist coating machine of the present invention includes a temperature control device for keeping the temperature of a photoresist tank housing part and a wafer chuck housing part holding a semiconductor wafer constant, and a temperature control device for measuring the film thickness of a photoresist film coated on the surface of a semiconductor wafer. It consists of a reflectance measuring device.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a configuration diagram of the first embodiment of the present invention;
Figures a and b are a top view and a side view of the cup of the first embodiment, and Figure 3 is a sectional view of the connection between the wafer chuck and the motor of the first embodiment.

In FIGS. 1 to 3, a tank storage box 11 that stores a photoresist tank 15 and a pump 14 that supplies photoresist to a nozzle 13 via a resist supply pipe 8, and a wafer chuck 16 that holds a wafer 21 are housed therein. The inside of the chuck storage box 1, which houses the cup 2 and the motor 4, is kept at a constant temperature by clean air at a constant temperature from a temperature control device 9 consisting of a heater and a cooler.

In other words, the inside of the tongue storage box 11 is indicated by arrow A.
Due to the flow of clean air shown in , clean air is sent into the chuck storage box 1 through the paper filter 22 as shown by arrows A and B, and is discharged from the duct hole 12 in the oven 5. ing.

Since the upper part of the cup 2 is open, the temperature around the wafer chuck 16 and the wafers 21 held in vacuum therein is also maintained at a constant temperature.

A coupling 3 is provided at the connection between the wafer chuck 16 and the motor 4, so that heat from the motor 4 is not transmitted to the wafer chuck 16.

Also, oven 5 and carrier box 1 for transport.
A reflectance measuring device 6 for measuring the film thickness of the photoresist coated on the wafer surface is provided between 3B, and an automatic film thickness measuring device 7 uses a signal from the reflectance measuring device 6 to measure the thickness of the photoresist coated on the wafer surface. It is now being displayed in real time.

In the first embodiment constructed in this way, the wafer 21 transported from the supply carrier box 13A is held in the wafer chuck 16 and coated with photoresist in the cup 2. At this time, the film thickness of the photoresist is not affected by the surrounding environment, so there is no variation in film thickness between wafers or between lots as in the prior art. Next, the wafer 21 is sent to the oven 5 and prebaked, and then the film thickness of the photoresist is measured in the reflectance measuring device 6, and then stored in the carrier box 13B for carrying out.

As described above, in the first embodiment, the photoresist film can be formed to have a uniform thickness, and the film thickness can be measured continuously in a short time, so that workability is improved.

In FIG. 1, reference numeral 10 is a waste liquid tank for storing the photoresist from the cup 2.

FIG. 4 is a configuration diagram showing a second embodiment of the present invention, and FIG. 5 is a wafer chuck 1 of the second embodiment.
6 is a sectional view showing a connecting portion between the motor 6 and the motor 4. FIG.

In this second embodiment, a resist tank 15,
The pump 14 and the cup 2 containing the wafer chuck are housed in the same box, and the temperature is controlled by a downflow type temperature control device 9A. Further, as shown in FIG. 5, the temperature of the wafer chuck 16 can be controlled by surrounding the connection part between the wafer hutch 16 and the motor 4 with a heat insulating cover 20 and feeding clean air directly through the temperature control device 9A or the air supply port 19A. Maintained. In addition, 17 is a vacuum nozzle, 19
B is an exhaust port.

In this way, in the second embodiment, the resist tank 15, the pump 14, the atmosphere inside and outside the cup 2, and the wafer chuck 16 can be temperature-controlled within the same box, so that the film thickness of the photoresist on the wafer 21 is more constant. There is an advantage that Therefore, a reproducible pattern can be obtained when the wafer is exposed.

〔Effect of the invention〕

As explained above, the present invention provides a temperature control device for keeping the temperature of the photoresist tank storage section and the wafer chuck storage section constant, and a reflectance measuring device for measuring the film thickness of the photoresist. A photoresist coating machine capable of forming a film with a uniform thickness and reducing working time can be obtained. Therefore, the manufacturing yield and reliability of semiconductor devices can be improved.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram of the first embodiment of the present invention;
Figures a and b are top and side views of the cup used in the first embodiment, Figure 3 is a sectional view of the connection between the wafer chuck and motor of the first embodiment, and Figure 4 is the cup used in the second embodiment of the present invention. The configuration diagram of the embodiment, FIG. 5 is the second embodiment.
FIG. 3 is a cross-sectional view of the connection portion between the wafer backpack and the motor in the embodiment. 1...Chick storage box, 2...Cup,
3... Coupling, 4... Motor, 5... Oven, 6... Reflectance measuring device, 7... Automatic film thickness measuring section, 8... Resist supply pipe, 9, 9A... Temperature adjustment device, 10... ... Waste liquid tank, 11 ... Tank storage box, 12 ... Duct hole, 13 ... Nozzle, 14 ... Pump, 15 ... Photoresist tank, 16 ... Wafer chuck, 17 ... Vacuum nozzle, 19A ... Air supply port, 19B...exhaust port, 20...insulation material cover, 21...wafer,
22...Paper filter.

Claims (1)

[Claims] 1. A temperature control device for keeping the temperature of the photoresist tank storage section and the wafer chuck storage section that holds semiconductor wafers constant, and a reflectance measuring device for measuring the film thickness of the photoresist film applied to the surface of the semiconductor wafer. A photoresist coating machine comprising: