JPH01307223A - Hot plate for resist hardening - Google Patents

Abstract

PURPOSE:To enable forming a thin part of resist film by forming a trench on a hot plate, and providing a part to which an object to be heated does not make contact. CONSTITUTION:A trench 6 is formed on the surface of a hot plate 3. When a glass substrate 2 is put on the hot plate 3 for resist hardening, and the hardening of resist 1 is begun, little solvent evaporates, because the thermal input is almost zero to the resist 1 corresponding with the part of the hot plate 3 where the trench 6 exists, as compared with the other part. Since the surface tension of the resin is generally higher than that of the solvent, the surface tension of the resist 1 where the solvent evaporates becomes higher as compared with the trench 6 part. As a result, the gradient of the surface tension generates between the part of the hot plate 3 where the trench 6 exists and the other part, and so the resist flows from the side where the trench exists to the part where the trench does not exist. Thereby, after the resist is hardened, the film thickness of the resist corresponding with the part of the hot plate 3 where the trench 6 exists can be thinly formed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an apparatus for curing colored resists used for semiconductor resists, liquid crystal televisions, solid-state image sensors, etc.

2. Description of the Related Art Conventionally, this type of hot plate for curing resist is used, as shown in FIG. (Fig. 3b), the solvent contained in the resist that was added to give fluidity and improve coating performance is evaporated, and the remaining resin component is heated and polymerized to harden. Although the average value of the film thickness decreased as shown in FIG. 3C, the main effect was to uniformly cure the film without changing the film thickness distribution during coating.

Problems to be Solved by the Invention Conventional hot plates for curing resist simply perform curing while maintaining the film thickness distribution on the substrate when resist is applied; could not give any change.

Means for Solving the Problems In the present invention, a groove is formed in a predetermined shape in a plane effective for curing the resist on a hot plate, and a portion is provided with which the object to be heated does not come into contact.

Function The present invention forms a thin portion in a predetermined shape in the curing process after applying the resist using the above-described configuration.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a cross-sectional view showing the structure of the resist curing hot plate of the present invention and an example of its temperature distribution, and FIG. 2 is a process diagram showing the resist curing process using this resist curing hot plate. . Note that the same numbers are given to common inlets in FIGS. 1 to 3.

In FIG. 1, 3 is a resist hardening hot plate made of a good thermal conductor such as aluminum, copper, iron, etc.;
is a heating resistance coil made of nichrome, tantalum, etc. embedded within it. Reference numeral 5 denotes a power source that supplies voltage to the heating resistance coil 4. There are two grooves 6 on the surface of the hot plate 3.
In this part, there is an air layer with poor thermal conductivity between the object to be heated and the hot plate, so there is almost no heat input to the object to be heated.

Next, the resist curing process will be explained with reference to FIG. Fig. 2 a shows the resist and toner coating using a spinner, roll coater, etc.
This is the glass substrate 2 immediately after it has been uniformly coated. At this time, the resist 1 is uncured and contains a large amount of solvent component. Next, this glass substrate 2 is placed on a hot plate 3 for curing the resist.
Place the resist on top and begin to harden the resist (Figure 2b). At this time, since the resist corresponding to the groove 6 of the hot plate 3 receives almost no heat input compared to other parts, the solvent evaporates less. Generally, the surface tension of the resin is higher than the surface tension of the solvent, so the surface tension of the resist in areas where the solvent evaporates is higher than that in the groove areas. In other words, a surface tension gradient is generated between a portion of the hot plate 3 where the grooves 6 are located and another portion, and as a result, the resist flows from the side where the grooves are present to the side where there are no grooves. As a result, after the resist hardens, the resist film thickness corresponding to the grooved portions of the hot plate 3 becomes thinner, as shown in FIG. 2C. Also, the film thickness on both sides of the grooved portion becomes slightly thicker, but it is not noticeable because it is easily diffused. The difference in film thickness between the thinner part and the other parts is proportional to the uncured film thickness, the temperature gradient of the hot plate, etc.
Inversely proportional to resist viscosity.

An example of the use of the resist film according to the present invention will be described. Consider the case where a color T-filter for a liquid crystal color television is formed using black, red, green, and blue colored resists. After forming the black matrix with black resist, R1G, H
When each pixel is exposed using the same mask and shifted by one pixel, resist remains on the outer frame part of the black matrix, and the film thickness in this part protrudes, causing the array side glass on which liquid crystal driving electrodes etc. are formed to be exposed. This caused a crack between the opposing electrode and the substrate. However, by hardening the RlG and B resists using a hot plate with grooves formed in the portions corresponding to the black frame portions of the black matrix, the resists on the black frame portions become thinner, and the above-mentioned problem is solved. Eliminate.

Effects of the Invention The present invention enables the resist to be coated uniformly on a glass substrate, etc., and then placed on a hot plate to harden. A thin portion can be formed.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of the structure of a resist curing hot plate according to an embodiment of the present invention, Fig. 2 is a resist curing process diagram using the resist curing hot plate of the present invention, and Fig. 3 is a conventional resist curing process. It is a hardening process diagram of an example. 1...Resist, 2...Glass substrate, 3...
・Hot plate for curing resist, 4... heat generating resistance wire, 6... groove. Name of agent: Patent attorney Toshio Nakao and 1 other person 3 --- Netf 0 sheet O --- Mizo 4 -- One idea, short-looking Koishi Figure 1 Figure 2

Claims (1)

[Claims] 1. A hot plate for curing a resist, characterized in that a groove is formed in a predetermined shape in a plane effective for curing a resist, and a portion that does not come into contact with an object to be heated is provided.