KR20030028303A - Apparatus and method for forming photoresist film - Google Patents

Abstract

PURPOSE: Provided are a method for forming a photoresist film which reduces time required to apply a photoresist in a spraying method and substantially increases productivity, and a device for forming a photoresist film. CONSTITUTION: The device comprises a photoresist storage tank(120) for storing and discharging a photoresist pressurized at the first fluid pressure; a buffer tank(150) for pressurizing and discharging the photoresist discharged from the storage tank; a slit spray head(200) for spraying the photoresist; a conveyer for conveying the slit spray head; and a photoresist blocking unit for blocking a feed of photoresist from the slit spray head. The photoresist discharged from the buffer tank is filtered by filter. The first and the second fluid pressures are controlled by pressure controller(130,160).

Description

Photoresist film forming apparatus and photoresist film forming method using same {APPARATUS AND METHOD FOR FORMING PHOTORESIST FILM}

The present invention relates to a photoresist film forming apparatus and a method of forming a photoresist film using the same, and more particularly, the overall time required for applying the photoresist is greatly shortened, thereby improving productivity and greatly improving equipment operation efficiency. A photoresist film forming method and a photoresist film forming apparatus using the same.

In general, a photoresist film is selected by a thin film forming process to protect selected portions of the thin film from the etchant to prevent etching, and only the unselected portions are etched by the etchant. Play a role.

In order to perform such a function, the photoresist film should have photosensitive and high film uniformity in response to light.

In order to form a photoresist film having such characteristics, the photoresist is dropped at a center of rotation while rotating the substrate on which the photoresist film is to be formed at a high speed so that the photoresist is applied to a uniform thickness throughout the substrate by centrifugal force. So-called "spin coaters" and "spin coating methods" are mainly used.

Such a spin coating method and spin coater are particularly suitable for forming a photoresist film on a substrate such as a wafer of relatively small size.

However, such a photoresist film forming technique by the spin coating method is not very suitable for applying to a liquid crystal display device which has been rapidly developed in recent years.

Specifically, the liquid crystal display panel, which is a portion where a screen is displayed in the liquid crystal display device, is divided into a color filter substrate and a TFT substrate, and these substrates are formed on at least one or more sheets simultaneously on a large large mother substrate to increase productivity. Individualized from the mother board and assembled.

At this time, the mother substrate has a lot of difficulty in high-speed rotation because the plane and weight of the wafer is much larger than the wafer, and there is a lot of photoresist that is not actually patterned, and the photoresist rotates at a high speed as the weight is heavy. The problem that the time required for stopping increases.

Recently, in order to overcome such a problem, a slit injection type photoresist film forming apparatus rather than a spin coating method has been introduced.

With reference to the accompanying Figure 1 will be described a conventional slit spray nozzle type photoresist film forming apparatus that improves the problem of the spin coating method.

The conventional slit nozzle type photoresist film forming apparatus 100 is generally viewed as a photoresist storage tank 10, a buffer tank 30, a photoresist pressurization device (not shown), a filter 45, a pump 60, and a connection pipe. It consists of (20,40,50,70).

More specifically, the photoresist storage tank 10 and the buffer tank 30 are connected by a connecting pipe shown by reference numeral 20. The photoresist stored in the photoresist storage tank 10 can be supplied to the buffer tank 30 by this connecting pipe 20.

At this time, the pressure piping shown by the reference numeral 5 is connected to the pressurization device, one end is not shown and the other end is connected to the photoresist storage tank 10 to pressurize the photoresist stored in the photoresist storage tank 10 . At this time, the gas applied to the photoresist storage tank 10 is N ₂ gas, and the pressure is about 0.6 Kgf / cm 2.

The photoresist pressurized to the photoresist storage tank 10 is supplied to the buffer tank 30 through the connection pipe 20.

On the other hand, the photoresist forcedly transferred to the buffer tank 30 is supplied to the filter 45 via the connection pipe 40 under the condition that the pressure of N ₂ gas of 0.5 Kgf / cm ₂ is further applied.

In this case, the filter 45 serves to filter various impurities included in the photoresist. The photoresist that has passed through the filter 45 is again supplied to the photoresist supply pump 60.

Thereafter, the photoresist of which the supply amount is adjusted in the photoresist supply pump 60 is supplied to the slit ejection head 80 in which the long slit-shaped opening is formed and then ejected to the outside to be compared with the substrate 90, for example, a wafer. It is applied to the top surface of a very large rectangular parallelepiped substrate.

In the photoresist film forming apparatus 100 having such a configuration, the photoresist supply pump 60 receives the photoresist discharged from the photoresist storage tank 10 and the buffer tank 30 to the slit injection head 80. Has a mechanism to feed.

However, the photoresist supply pump 60 of the conventional photoresist film forming apparatus 100 has a problem in that productivity is greatly reduced because a time in which the process cannot be performed periodically occurs because performance deterioration occurs periodically.

In addition, when the performance of the photoresist supply pump 60 is deteriorated, the discharge amount discharged from the photoresist supply pump 60 is changed, and eventually, the feed speed of the slit injection head 80 is also gradually reduced in accordance with the discharge amount. In other words, this means that the time required to apply the photoresist is increased, as well as the productivity is greatly reduced.

Accordingly, the present invention has been made in view of such a conventional problem, and a first object of the present invention is to apply a photoresist by spraying, and to shorten the time required to apply the photoresist by spraying, thereby greatly improving productivity. The present invention provides a method for forming a resist thin film.

In addition, a second object of the present invention is to provide a photoresist thin film forming apparatus in which the photoresist is applied by spraying, and the time required for applying the photoresist by spraying is greatly improved to improve productivity.

1 is a conceptual diagram of a conventional photoresist thin film forming apparatus.

2 is a conceptual diagram of a photoresist thin film forming apparatus according to an embodiment of the present invention.

3 is a conceptual diagram illustrating a relationship between a slit jet head and a substrate according to an embodiment of the present invention.

The photoresist thin film forming apparatus for realizing the first object of the present invention includes a photoresist storage tank in which a photoresist pressurized with a first fluid pressure is stored and discharged, and a photoresist discharged from a photoresist storage tank is supplied. 2 A slit injection head and a slit injection head which receive a buffer tank for pressurizing and discharging at a fluid pressure and a photoresist discharged from a buffer tank toward a photoresist application end from a photoresist application start position of the substrate. In order to block the supply of the photoresist supplied from the slit ejection head before the slit ejection head reaches the photoresist application end position in consideration of the transfer device for transferring the photoresist and the amount of photoresist supplied excessively at the photoresist application end position. Photoresist Shielding Means;

In addition, the method for forming a photoresist thin film for realizing the second object of the present invention comprises the steps of: discharging the photoresist stored in the closed space by the first fluid pressure supplied from the outside, the photoresist is supplied to the closed space After the step of storing in the re-pressurized by the second fluid pressure and ejecting to the outside, spraying the discharged photoresist in the direction from the application start position of the substrate toward the application end position, the amount of photoresist supplied excessively at the application end position In consideration of the above, the step of blocking the supply of the photoresist before reaching the application end position and the step of allowing the photoresist to be supplied even up to the application end position with a surplus supplied photoresist.

Hereinafter, with reference to the accompanying drawings, a unique action and effects of the photoresist thin film forming method and the photoresist thin film forming apparatus according to an embodiment of the present invention will be described.

First, the photoresist film forming apparatus 220 for forming the photoresist film in a short time will be described with reference to FIG. 2.

The photoresist film forming apparatus 220 is generally viewed as a photoresist storage tank 120, a buffer tank 150, a pressure regulating device 130, 160, a slit spray head 200, a slit spray head 200, a shielding solenoid valve. It consists of 192.

Specifically, the photoresist storage tank 120 is a container in which the photoresist is stored, and the photoresist storage tank 120 includes two as shown in FIG. 2.

Hereinafter, any one of the two photoresist storage tanks 120 will be referred to as a first photoresist storage tank 110 and the rest will be referred to as a second photoresist storage tank 115.

The first and second pressurized pipes 132 and 134 shown in reference numerals 132 and 134 are connected to the first and second photoresist storage tanks 110 and 115 defined as described above. The first pressurizing device 130 is simultaneously connected to the pipes 132 and 134. Reference numerals 135 and 136 are on / off valves for opening and closing the first and second pressurized pipes 132 and 134.

The first pressurizing device 132 serves to apply “first fluid pressure” to the photoresist stored in the first and second photoresist storage tanks 110 and 115. As a result, the photoresist has a property of moving to a lower pressure than the “first fluid pressure”. At this time, the first pressurizing device 132 supplies nitrogen gas having a pressure of 0.5 to 0.7 Kgf / cm 2 into the first and second photoresist storage tanks 110 and 115.

Meanwhile, first and second discharge tubes 138 and 139 are formed in the first and second photoresist storage tanks 110 and 115 so that the pressurized photoresist may be discharged.

In this case, one end of each of the first and second discharge pipes 138 and 139 is connected to the first and second photoresist storage tanks 110 and 115, and the other end thereof is connected to each other. Reference numerals 138a and 139a are open / close valves formed in the first and second discharge pipes 138 and 139.

Meanwhile, one end of the common pipe 140 is connected to the first and second discharge pipes 138 and 139 which are connected to each other, and the other end of the common pipe 140 is connected to the buffer tank 150.

Such a pipe structure ensures that the photoresist supply is not interrupted even when the container is replaced by using the photoresist stored in any one of the first and second photoresist storage tanks 110 and 115.

Meanwhile, the second pressurizing device 160 is connected to the buffer tank 150. At this time, the second pressurizing device 160 supplies nitrogen gas having a pressure of 0.5-07 Kgf / cm 2 to the inside of the buffer tank 150 through the connection pipe 162. Reference numeral 164 denotes a shield valve, and 166 denotes a check valve.

As such, one end of the connection pipe 170 is connected to the buffer tank 150 to which the second pressurizing device 160 is connected, and the slit injection head 200 is connected to the other end of the connection pipe 170.

The slit injection head 200 serves to spray the photoresist in a direction from one end of the substrate 210 to the other end through the slit-shaped opening with a cylinder having a slit-shaped long opening at the bottom thereof.

In this case, in order to cause the slit ejection head 200 to eject the photoresist from one end of the substrate toward the other end, a transfer device 205 is required.

In this case, the faster the transfer device 205 transfers the slit jet head 200, the shorter the time required for the photoresist application process.

At this time, the speed at which the transfer device 205 transfers the slit injection head 200 is closely related to the pressing force in the buffer tank 150. This will be described in more detail with reference to Table 1 below.

0.5Kgf / ㎠ 0.55 Kgf / ㎠ 0.60 Kgf / ㎠ 0.65Kgf / ㎠ 0.70 Kgf / ㎠ 90mm / sec coating 100mm / sec Uncoated coating 110mm / sec Uncoated coating 120mm / sec Uncoated coating coating 125 mm / sec Uncoated Uncoated coating 130mm / sec Coated coating 135mm / sec Uncoated

Referring to Table 1, when the pressing force for pressurizing the photoresist in the buffer tank 150 is 0.5Kgf / cm 2 and the transfer device 205 transfers the slit jet head 200 at 90 mm / sec, accurate photoresist Application was made.

In addition, when the pressing force is 0.55Kgf / cm 2 When the transfer device 205 transfers the slit injection head 200 to about 100mm / sec was made accurate photoresist coating.

In addition, when the pressing force was 0.60 Kgf / cm 2, accurate photoresist coating was performed when the transfer device 205 transferred the slit jet head 200 to about 110 mm / sec.

In addition, when the pressing force is 0.65 Kgf / ㎠ and the conveying device 205 to transfer the slit injection head 200 to about 120mm / sec, accurate photoresist coating was made, the pressing force is 0.70 Kgf / ㎠ and the conveying device 205 The application of the correct photoresist was achieved by transferring the slit jet head 210 at about 130 mm / sec.

As a result, this means that the higher the pressing force for pressing the photoresist in the buffer tank 150, the faster the transfer device 205 can transfer the slit injection head 200.

Accordingly, in the present invention, a pressure of greater than 0.5 Kgf / cm 2 and less than 0.7 Kgf / cm 2 is formed in the buffer tank 150 based on the experiment. The conveying speed can be from 90mm / sec to 130mm / sec.

On the other hand, by optimizing the strength of the pressure applied to the buffer tank 150 as described above, it is also possible to optimize the feed speed of the slit injection head 200.

This advantage is obtained by adjusting the pressing force of the buffer tank 150 without using the photoresist pump used in the prior art.

However, when optimizing the feeding speed of the slit injection head 200 by adjusting only the pressing force of the buffer tank 150 without using the photoresist pump as in the prior art, the photoresist film thickness non-uniformity at the end of the photoresist film is Occurs.

This is because a small amount of photoresist is further supplied by the injection pressure, no matter how quickly the supply of the photoresist is blocked at the designated position. Such photoresist supplied more than the designated amount will be defined as “excess photoresist”.

Such excess photoresist causes waste of photoresist and uneven thickness of the photoresist film. In order to prevent this, in the present invention, the photoresist blocking solenoid valve 192 is formed in the connection pipe 190.

At this time, the photoresist blocking solenoid valve 192 is formed to be close to the slit injection head 200 as possible.

On the other hand, between the buffer tank 150 and the connecting pipe 190 connecting the slit injection head 200 is shown by reference numeral 180 and a filter for removing impurities contained in the photoresist is installed.

Hereinafter, a photoresist film forming method by a photoresist film forming apparatus according to an embodiment of the present invention having such a configuration will be described with reference to the accompanying drawings.

First, a first fluid pressure having a size of greater than 0.7 Kgf / cm 2 and less than or equal to 0.9 Kgf / cm 2 is supplied to the photoresist storage tank 120 to discharge the photoresist from the photoresist storage tank 120 to the outside.

Subsequently, the discharged photoresist flows back into the buffer tank 150 via the common pipe 140. At this time, the second fluid pressure acting on the buffer tank 150 again is larger than 0.5 Kgf / cm 2 and has a size of 0.7 Kgf / cm 2 or less.

By the second fluid pressure, the photoresist of the butter tank 150 is again supplied to the slit injection head 200 through the connection pipe 190 and the filter 190.

As soon as the slit ejection head 200 is supplied to the slit ejection head 200, the slit ejection head 200 starts photoresist ejection at point A as shown in FIG. 3 and then photoresist toward the C direction at the speed designated by the transfer device 205. To be sprayed.

As such, the photoresist injected from the slit injection head 200 is transferred to the point C while the photoresist blocking solenoid valve 192 is closed at the point B which is less than the point C. At this time, although the photoresist blocking solenoid valve 192 is closed at the point B which is less than the point C, the photoresist having a branch C is accurately supplied by the surplus photoresist supplied from the photoresist blocking solenoid valve 192. The desired photoresist film is formed.

As described in detail above, not only the components of the apparatus for forming the photoresist film can be simplified, but also the time required for forming the photoresist film can be greatly shortened, thereby greatly reducing the production cost and greatly improving the production efficiency. That has various effects.

In the detailed description of the present invention described above with reference to a preferred embodiment of the present invention, those skilled in the art or those skilled in the art having ordinary knowledge in the scope of the invention described in the claims to be described later It will be understood that various modifications and variations can be made in the present invention without departing from the scope of the present invention.

Claims (8)

A photoresist storage tank in which the photoresist pressurized with the first fluid pressure is stored and discharged; A buffer tank which receives the photoresist discharged from the photoresist storage tank and pressurizes and discharges the photoresist with a second fluid pressure; A slit injection head receiving the photoresist discharged from the buffer tank and injecting the photoresist in a direction from a photoresist application start position of a substrate to a photoresist application end position; A conveying apparatus for conveying the slit ejection head; And Photoresist for blocking supply of the photoresist supplied from the slit ejection head before the slit ejection head reaches the photoresist application end position in view of the amount of photoresist supplied excessively at the photoresist application end position A photoresist film forming apparatus comprising shielding means. The photoresist film forming apparatus of claim 1, wherein the photoresist discharged from the buffer tank is filtered by a filter. The apparatus of claim 1, wherein the first fluid pressure and the second fluid pressure are controlled by a pressure regulator. The method of claim 1, wherein when the second fluid pressure is greater than 0.5Kg / ㎠ and less than 0.7Kg / ㎠, the feed speed of the slit injection head is 90mm / sec or more and 130mm / sec or less in proportion to the second fluid pressure A photoresist film forming apparatus. The photoresist film forming apparatus according to claim 1, wherein the photoresist shielding means is a solenoid valve which is opened and shielded by a control signal. Iv) discharging the photoresist stored in the closed space by the first fluid pressure supplied from the outside; Ii) receiving the photoresist and storing the resultant in an enclosed space and then repressurizing it with a second fluid pressure and discharging it to the outside; Iii) spraying the discharged photoresist in a direction from the application start position of the substrate toward the application end position; Iv) blocking the supply of the photoresist before reaching the application end position in view of the amount of photoresist supplied excessively at the application end position; And Iii) allowing the photoresist to be even supplied to the photoresist that has been supplied excessively up to the application end position. 7. The formation of the photoresist film according to claim 6, wherein the first fluid pressure is greater than 0.7 Kg / cm 2 and less than or equal to 0.9 Kg / cm 2, and the second fluid pressure is greater than 0.5 Kg / cm 2 and greater than or equal to 0.7 Kg / cm 2. Way. 8. The method of forming a photoresist film according to claim 7, wherein the spraying speed of the photoresist is 90 mm / sec or more and 130 mm / sec or less corresponding to the range of the second fluid pressure.