JPH09230603A - Exposure method - Google Patents

Abstract

(57) An object of the present invention is to obtain a high total pitch accuracy by reducing the difference in deviation amount between the total pitches of the pattern surface in the X direction and the Y direction in a batch exposure type exposure apparatus. A shim is attached only to a fixed portion that is in the middle of a long side direction of a substrate stage, and a stage on which a substrate to be exposed is placed is curved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a collective exposure method for a large area pattern such as a color filter, a black matrix or a thin film transistor (TFT) electrode substrate used in a liquid crystal display device or the like.

[0002]

2. Description of the Related Art In order to perform color display in a color liquid crystal display device, a light-shielding layer (black matrix) having a light-transmitting opening is formed on a transparent substrate, and a red light is partially overlapped with the opening and the light-shielding layer. Color filters having patterned green, green, and blue filter layers are generally used. Recently, the market demand for liquid crystal display devices is to improve the aperture ratio of the color filter for higher brightness and lower power consumption, and to increase the added value of products using liquid crystal display devices. There is an urgent need for higher definition. Therefore, the pixel pattern of the black matrix is becoming even finer, and the improvement of the pitch accuracy (total pitch accuracy) of the entire substrate, which holds the key to the bonding of the thin film transistor (TFT) and the color filter from the customer. Is being requested.

In order to bring this total pitch closer to the target value, improvement is currently made by adjusting the temperature of the temperature control chamber. However, when there is a difference in the total pitch between the X direction and the Y direction, which are in an orthogonal relationship, There is a problem in that either the X direction or the Y direction may be out of the standard only by adjusting the temperature.

Consideration was made in order to bring out the desired temperature control direction of the temperature control chamber. As an example, long side (X
When a pattern is exposed at a certain temperature through a mask on a substrate whose direction (direction) is 450 mm and whose short side (Y direction) is 350 mm, the deviation of the transfer pitch value at each position shown in FIG. 5 from the design value Table 1 below shows the result of simulating the change in transfer accuracy when the (transfer amount deviation amount) is obtained and the temperature condition in the chamber is changed with reference to this. The expansion coefficient of the mask was 9.2 × 10 ⁻⁶ m / ° C., and the expansion coefficient of the substrate was 4.7 × 10 ⁻⁶ m / ° C. In the table, Rxy is the X direction,
The maximum difference of the deviations of the transfer position values in the Y direction from the design values is shown. The reason that Rxy is different from the value obtained from the numerical values in the table is that the numerical values in the table are rounded to one decimal place.

[0005]

[Table 1]

From this simulation result, it is understood that Rxy decreases when the chamber temperature is lowered. However, since the transfer accuracy itself is greatly deteriorated in the negative direction, there is a problem. Therefore, it is considered that there is a limit to the pitch correction by temperature adjustment in both X and Y directions.

[0007]

SUMMARY OF THE INVENTION The present invention is directed to the X direction and the Y direction.
It is an object of the present invention to provide a measure for solving the above problem by reducing and correcting the difference in the deviation amount of the total pitch in the direction.

[0008]

According to the present invention, in an exposure apparatus of a batch exposure system, a stage on which a substrate to be exposed is placed is curved to bend the substrate to be exposed, and the X and Y directions of a pattern surface. The exposure method is characterized by reducing the difference in the deviation amount of the total pitch in the above.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Conventionally, as shown in FIG.
For the stage 4 on which the substrate 6 to be exposed is placed, screw fixing 2 is placed on a fixed column 1 for fixing the stage 4 with screw holes aligned, and the stage 4 is placed thereon, and a screw 5 is attached. It is to be tightened and fixed with. However, according to the present invention, among the fixing portions indicated by the circles in FIG. 3, only the fixing portions corresponding to the middle of the X direction indicated by the black circles are shimmed on the screw stoppers 2 placed on the fixing columns 1 as shown in FIG. After arranging 3,
Place the stage 4 and tighten it with screws 5.

As a result, as shown in FIG. 1, in the stage 4 which has been fixed to the fixed column 1, the central portion in the X direction fixed by sandwiching the shim 3 slightly rises, and the X direction is curved as a whole. . As a result, the substrate 6 placed on the stage 4 is also curved. When pattern exposure is performed through the mask 7 in this state, the deviation of the total pitch of the pattern formed on the substrate 6 is improved only in the X direction in the positive direction.

[0011]

EXAMPLE By the method described in the above embodiment, the shim 3 having a thickness of 50 μm was attached to the fixed portion of the exposure machine in the middle of the long side of the stage 4, and the pattern exposure was performed with the stage 4 curved. went. As a result, as shown in Table 2 below, the difference Rxy in the deviation amount from the design value of the transfer value in each of the X direction and the Y direction was improved from 3.5 μm to 1.4 μm.

[0012]

[Table 2]

[0013]

According to the method of the present invention, the maximum difference in the total pitch deviation amount in the X direction and the Y direction is improved, and a large area pattern having a pattern with higher definition, which has been impossible in the past, is obtained. Mass production with high pitch accuracy is now possible.

[0014]

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of an exposure method of the present invention.

FIG. 2 is a cross-sectional view showing an example of a stage fixing section according to a conventional method and a stage fixing section without a shim in the method of the present invention.

FIG. 3 is an explanatory view showing an example of a position of a stage fixing portion of the present invention.

FIG. 4 is an explanatory diagram showing an example of a stage fixing portion that sandwiches a shim in the method of the present invention.

FIG. 5 is an explanatory diagram showing a total pitch measurement position within a substrate surface.

[Explanation of symbols]

 1 fixed pillar 2 screwing 3 shim 4 stage 5 screw 6 substrate 7 mask

Claims (1)

[Claims] 1. In a batch exposure type exposure apparatus, a stage on which a substrate to be exposed is placed is curved to bend the substrate to be exposed, and a deviation amount of a total pitch in X and Y directions of a pattern surface is measured. An exposure method characterized by reducing the difference.