JPH08262734A - Resist applying device - Google Patents

Abstract

PURPOSE: To prevent the film thickness destruction on a substrate surface without affecting resist applying performance by decreasing the static electricity quantity generated in the substrate. CONSTITUTION: This resist applying device is constituted to wash the substrate P in a washing treatment section 5, to dry the substrate P washed in a drying treatment section and to apply a resist on the dried substrate P in a resist applying section. This washing treatment section 5 has an antistatic agent applying means 21 for applying an antistatic agent on the rear surface of the substrate P. The antistatic agent is applied on the rear surface of the substrate P in the washing treatment section 5 in the fore stage of the drying treatment section and, therefore, the static electricity quantity generated in the substrate P is decreased. The spark discharge induced by the static electricity is suppressed and the thin film destruction on the substrate surface is prevented without affecting the resist applying performance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist coating apparatus for coating a substrate with a resist.

[0002]

2. Description of the Related Art Generally, a liquid crystal display device has a structure in which a liquid crystal material is sandwiched between a pair of substrates having thin film electrodes. The thin film electrode of this substrate is manufactured through the steps of film formation, resist coating, exposure, development and etching.

FIG. 2 shows a schematic view of a resist coating apparatus used in resist coating during this step. The resist coating apparatus includes a loader unit 1, a cleaning processing unit 5 including a brush cleaning unit 2, a spin scribing unit 3, and a spin drying unit 4, a drying oven unit 6 as a drying processing unit, a resist coating unit 7, and a pre-baking unit. It is composed of an oven section 8 and an unloader section 9.

Between the brush cleaning unit 2 and the spin scribing unit 3, between the spin scribing unit 3 and the spin drying unit 4, between the spin drying unit 4 and the drying oven unit 6, the drying oven unit 6 and the resist coating unit. 7, a swivel arm 10 for moving the substrate from the upstream process to the downstream process is disposed between the resist coating unit 7 and the pre-bake oven unit 8.

Then, in the loader unit 1, a cassette 11 accommodating a plurality of substrates is mounted, and the substrates are taken out from the cassette 11 one by one and sent to the brush cleaning unit 2.

In the cleaning processing unit 5, the brush cleaning unit 2 conveys the substrate between the rotating roll brushes to clean the front and back surfaces of the substrate, and then the spin scribing unit 3 rotates the substrate steadily. The surface of the substrate is cleaned by applying a megasonic rinse or a high-pressure rinse to the surface of the substrate, and then the substrate is rotated at a high speed in the spin dry unit 4 to shake off the rinse liquid adhering to the substrate.

In the drying oven section 6, the substrate is heat-treated to completely remove the moisture remaining on the substrate and dry it. In the drying oven section 6, in order to prevent the resist from peeling off during development, the surface of the substrate is subjected to adhesion treatment at the HMDS position.

In the resist applying section 7, the resist is dropped while the substrate is being rotated steadily to uniformly apply the resist to the surface of the substrate.

In the pre-bake oven section 8, the substrate is heat-treated, the resist solvent applied to the substrate is removed, and the resist is baked and solidified.

In the unloader unit 9, an empty cassette 11 capable of accommodating a plurality of substrates is mounted, and the substrate after resist coating received from the pre-bake oven unit 8 is set in the cassette.
Store in 11 in sequence.

The structure of the spin dry unit 4 is shown in FIG.
Shown in The spin dry unit 4 has a drive unit 12 for rotating the substrate P, and shakes off the rinse liquid of the spin scribe unit 3 by the high speed rotation of the substrate P. At this time, in order to prevent stains and unevenness due to the drying of the rinse liquid during the transportation from the spin scribing unit 3 to the spin drying unit 4 and the adhesion of dust during the transportation, the substrate P is initially rotated at a low speed while the surface is rotated. Side rinse liquid ejecting means 13 and back side rinse liquid ejecting means 14 eject a rinse liquid such as pure water to the front and back surfaces of the substrate 1 for cleaning, and then rotate the substrate P at a high speed to shake off the rinse liquid. ,dry.

Further, in the drying oven section 5 and the pre-bake oven section 8, adsorption processing for adsorbing the substrate on the stage is performed. In this adsorption process, a small amount of air between the substrate and the stage and the air around the substrate and the stage are sucked through the suction holes communicating with the surface of the stage,
Vacuum adsorption of the substrate.

[0013]

By the way, in the conventional apparatus, as shown in the graph of FIG. 3 showing the transition of the substrate surface potential at each measurement position of the drying oven section and the prebaking oven section, the drying oven section 5 and the prebaking section are shown in FIG. When the adsorption process is performed in the oven unit 8, air rubs against the back surface of the substrate, and the back surface of the substrate and the surface of the suction stage are charged with static electricity due to friction. When the charged substrate is lifted from the oven, the electrostatic capacity of the electric field created between the oven and the substrate becomes small, and the surface potential of the substrate rises.
In particular, in a cooling plate before resist coating where the substrate can be lifted highest, the surface potential of the substrate is also high, and sometimes spark discharge occurs between the substrate and the swivel arm 10.
There is a problem that the thin film electrode on the surface of the substrate is destroyed.

The cause of the spark discharge is that electrostatic charge is caused by the adsorption processing of the substrate, and the electrostatic capacity of the electric field due to the static electricity of the substrate changes during the transportation of the substrate to cause dielectric breakdown.

Therefore, in order to prevent spark discharge, it is necessary to reduce the amount of static electricity charged on the substrate.

Therefore, it is possible to abolish the substrate adsorption process. However, especially with respect to the cooling plate before resist application, by removing the adsorption process, the problems of the uniformity of the in-plane temperature of the substrate and the inadequate cooling of the substrate remain, resulting in the deterioration of the resist film thickness distribution within the substrate surface. It is difficult to abolish the substrate adsorption process because it affects the resist coating performance.

An object of the present invention is to provide a resist coating apparatus capable of reducing the amount of static electricity generated on a substrate and preventing film thickness destruction on the substrate surface without affecting the resist coating performance.

[0018]

According to the present invention, there is provided a cleaning processing section for cleaning a substrate, a drying processing section for drying a substrate cleaned by the cleaning processing section, and a resist for the substrate dried by the drying processing section. In the resist coating apparatus including a resist coating section for coating the above, the cleaning processing section includes an antistatic agent coating means for coating an antistatic agent on the back surface of the substrate.

[0019]

According to the present invention, since the antistatic agent is applied to the back surface of the substrate in the cleaning processing section which is the previous step of the drying processing section, the amount of static electricity generated on the substrate in the drying processing section is reduced.

[0020]

EXAMPLES The construction of one example of the resist coating apparatus of the present invention will be described below. It should be noted that the same reference numerals are used for the same structures as those described in the related art, and the description thereof will be omitted.

As shown in FIG. 2, the resist coating apparatus is
A loader unit 1, a cleaning unit 5 including a brush cleaning unit 2, a spin scribing unit 3, and a spin drying unit 4, a drying oven unit 6 as a drying unit, and a resist coating unit 7.
And a prebake oven section 8 and an unloader section 9.

Between the brush cleaning unit 2 and the spin scribing unit 3, between the spin scribing unit 3 and the spin drying unit 4, between the spin drying unit 4 and the drying oven unit 6, the drying oven unit 6 and the resist coating unit. 7, a swivel arm 10 for moving the substrate from the upstream process to the downstream process is disposed between the resist coating unit 7 and the pre-bake oven unit 8.

In the loader unit 1, a cassette 11 containing a plurality of substrates is mounted, and the substrates are taken out from the cassette 11 one by one and sent to the brush cleaning unit 2.

In the cleaning processing unit 5, the brush cleaning unit 2 conveys the substrate between the rotating roll brushes to clean the front and back surfaces of the substrate, and then the spin scribing unit 3 rotates the substrate steadily. The surface of the substrate is cleaned by applying a megasonic rinse or a high-pressure rinse to the surface of the substrate, and then the substrate is rotated at a high speed in the spin dry unit 4 to shake off the rinse liquid adhering to the substrate.

In the drying oven section 6, heat treatment is applied to the substrate so that moisture remaining on the substrate is completely blown off and the substrate is dried. In the drying oven section 6, in order to prevent the resist from peeling off during development, the surface of the substrate is subjected to adhesion treatment at the HMDS position.

In the resist coating section 7, the resist is dropped while the substrate is being rotated steadily, so that the resist is uniformly coated on the surface of the substrate.

In the pre-bake oven section 8, the substrate is heat-treated, the resist solvent applied to the substrate is removed, and the resist is baked and solidified.

In the unloader unit 9, an empty cassette 11 capable of accommodating a plurality of substrates is mounted, and the substrate after resist coating received from the pre-bake oven unit 8 is set in the cassette.
Store in 11 in sequence.

In the drying oven section 6 and the pre-bake oven section 8, the substrate is subjected to adsorption treatment.

The spin dry section 4 has a drive unit 12 for rotating the substrate P, as shown in FIG.
In addition, the substrate P has a rinse liquid ejecting means 13 for ejecting a rinse liquid such as pure water, and an antistatic agent applying means 21 for applying an antistatic agent on the back surface of the substrate P. The antistatic agent applying means 21 has a tank 22 for accumulating the antistatic agent, supplies nitrogen gas (N ₂ ) to the upper part of the tank 22, and a plurality of nozzles connected to the lower part of the tank 22 by the gas pressure. The antistatic agent is discharged onto the back surface of the substrate P from 23.

In the spin dry section 4, first, in order to prevent stains and unevenness due to drying of the rinse liquid during transport from the spin scribing section 3 to the spin dry section 4 and adhesion of dust during transport, While rinsing P at a low speed, a rinse liquid such as pure liquid is discharged from the rinse liquid discharging means 13 onto the surface of the substrate 1 for cleaning. At the same time, the antistatic agent applying means 21 discharges and applies the antistatic agent to the back surface of the substrate P.

Thereafter, the discharge of the antistatic agent from the antistatic agent applying means 21 is stopped, and then the discharge of the rinse liquid from the rinse liquid discharging means 13 is stopped. In this way, by discharging the rinse liquid onto the front surface of the substrate P longer than the time during which the antistatic agent is discharged onto the rear surface of the substrate P, it is possible to prevent the antistatic agent from flowing around to the front surface of the substrate P. .

Thereafter, the substrate P is rotated at a high speed to shake off the rinse liquid, make the antistatic agent uniform, and dry it.

As described above, by applying the antistatic agent to the back surface of the substrate P in the spin dry section 4 of the cleaning processing section 5, even if the substrate P is adsorbed in the drying oven section 6 and the prebake oven section 8. The amount of static electricity generated on the substrate P can be suppressed.

That is, the back surface of the substrate P, that is, the suction surface of the suction treatment is made conductive by the antistatic agent. Since the static electricity generated by the adsorption process flows through the antistatic agent, the amount of static electricity charged on the substrate P is reduced.

This is because the drying oven section 6 shown in FIG.
Also, it can be seen from the graph showing the transition of the substrate surface potential at each measurement position of the prebake oven section 8. In the figure, the curve indicated by the solid line is the antistatic agent applied to the substrate P, and the curve indicated by the broken line is the antistatic agent not applied. From the measurement results, it can be seen that the surface voltage of the substrate P is greatly reduced by applying the antistatic agent. From this, it can be seen that by applying the antistatic agent to the substrate P, the amount of static electricity generated by the adsorption process of the substrate P can be reduced.

Therefore, the amount of static electricity generated when the substrate P is subjected to the adsorption treatment in the drying oven section 6 or the pre-baking oven section 8 can be reduced, and therefore, the resist coating performance is not affected, Spark discharge caused by static electricity can be suppressed to prevent the thin film on the surface of the substrate P from being broken.

Moreover, since the antistatic agent is applied only to the back surface of the substrate P, the resist adhesion is improved by mixing or combining with the adhesion processing agent of the adhesion processing applied to the surface of the substrate P in the drying oven section 6. Since the decrease can be ignored, the selection of the antistatic agent can be made arbitrarily.

Then, by receiving the arbitrariness of selection of the antistatic agent, by washing the substrate P with water, the applied antistatic agent is dissolved in water and the antistatic effect of the water-soluble solution is lost. You may select as an agent. This antistatic agent loses its antistatic effect for the first time in the water washing section of the developing device after resist coating and exposure, and suppresses the amount of static electricity generated on the substrate even in an exposure device that undergoes an adsorption treatment like the resist coating device. It is possible to do so, and there is no influence on the subsequent steps.

Therefore, it is possible to reduce the amount of static electricity generated when the substrate P is subjected to the adsorption treatment in the drying oven section 6 or the pre-bake oven section 8 and the like, and it is possible to suppress the spark discharge caused by this static electricity. P
The destruction of the thin film on the surface of the can be prevented. Also,
The adsorption treatment can be performed in the drying oven section 6 and the pre-bake oven section 8 and does not affect the resist coating performance, and since the antistatic agent is applied only to the back surface of the substrate P, the resist adhesion is also affected. Absent.

[0041]

According to the present invention, since the antistatic agent is applied to the back surface of the substrate in the cleaning unit in the previous step of the drying unit, the amount of static electricity generated on the substrate can be reduced.
Therefore, it does not affect the resist coating performance, suppresses the spark discharge caused by static electricity,
It is possible to prevent thin film destruction on the substrate surface. Moreover, since the antistatic agent is applied only to the back surface of the substrate, the adhesiveness of the resist is not affected.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a spin dry section of a cleaning processing section showing an embodiment of a resist coating apparatus of the present invention.

FIG. 2 is a perspective view of a resist coating apparatus.

FIG. 3 is a graph showing changes in substrate surface potential at each measurement position of a drying oven section and a pre-baking oven section.

FIG. 4 is an explanatory diagram of a spin dry unit of a conventional cleaning processing unit.

[Explanation of symbols]

 5 Cleaning Processing Section 6 Drying Processing Section 7 Resist Coating Section 21 Antistatic Agent Coating Means P Substrate

Claims (1)

[Claims] 1. A cleaning processing unit for cleaning a substrate, a drying processing unit for drying the substrate cleaned by the cleaning processing unit, and a resist coating unit for applying a resist to the substrate dried by the drying processing unit. In the provided resist coating apparatus, the cleaning processing unit includes an antistatic agent applying unit that applies an antistatic agent to the back surface of the substrate.