KR102423858B1 - Exposure Apparatus and Method - Google Patents

Abstract

The present invention controls the opening and closing of a slit having a through hole with the shield unit to create an overlapping area on the substrate on the stage, making the transfer directions of the shield unit and the stage the same, and changing the transfer speed to reduce the overlapping width of the overlapping area. To provide an exposure apparatus capable of reducing the number of exposure steps corresponding to a model or an MMG model.
In addition, the present invention includes the primary exposure step, the overlapping area forming step, the secondary exposure step, and the overlapping area full exposure step, and the transfer direction of the first shield unit and the stage in the overlapping area forming step and the overlapping area full exposure step It provides an exposure method that can reduce the overlapping width of the overlapping area and reduce the exposure type of a large model by controlling the same and differentially controlling the feed rate.

Description

Exposure apparatus and exposure method using the same

The present invention relates to an exposure apparatus and an exposure method using the same, and to an exposure apparatus and an exposure method using the same in which light irradiated from a light source passes through a pattern of a mask to perform exposure on a substrate.

In general, a liquid crystal display (LCD) has a tendency to gradually expand its application range due to features such as light weight, thin shape, and low power consumption driving. According to this trend, the liquid crystal display device is used for office automation equipment, audio/video equipment, and the like.

The liquid crystal display displays an image by adjusting the light transmittance of liquid crystal having dielectric anisotropy using an electric field.

To this end, the liquid crystal display device includes a liquid crystal display panel having a matrix of liquid crystal cells for displaying an image, and a driving unit for driving the liquid crystal display panel. An active matrix type liquid crystal display device that independently drives liquid crystal cells using a thin film transistor is widely used not only for a personal computer (PC) display device, but also for a television (TV).

The liquid crystal display panel includes a thin film transistor substrate and a color filter substrate facing each other, and liquid crystal injected between the two substrates.

The thin film transistor substrate includes gate lines and data lines, a thin film transistor formed as a switch element at each intersection region of the gate line and the data line, and a pixel electrode formed in units of liquid crystal cells and connected to the thin film transistor.

The color filter substrate includes color filters formed in units of excel, a black matrix for separating the color filters and reflecting external light, and a common electrode for supplying a common reference voltage to the liquid crystal cells.

A liquid crystal display panel is completed by separately manufacturing a thin film transistor substrate and a color filter substrate, bonding them, and then injecting and encapsulating the liquid crystal.

In the liquid crystal display panel, the thin film transistor substrate and the color filter substrate include a plurality of mask processes for pattern formation. Each mask process includes a thin film deposition process, a cleaning process, a photolithography process, an etching process, a photoresist stripping process, and an inspection process. Here, when the liquid crystal display panel is larger than the effective area of the exposure machine used in the photolithography process, a stitch for dividing and exposing the thin film transistor substrate and the color filter substrate, or a method of overlapping exposure by separately configuring XSMB and YMB units this is used

In this overlapping exposure method, a shield unit that selectively blocks light from a light source that will pass through a slit in the first exposure process and a stage on which a substrate is mounted are transported in different directions to form an overlapping area, which is an incomplete exposure area, and a second When the exposure process is performed, the overlapping area is additionally exposed, and the complete exposure is completed. At this time, when the shield unit and the stage are transported in different directions, the minimum overlapping width of the overlapping area is equal to the width of the slit.

However, the overlapping area formed in this way occupies a significant proportion compared to the total exposure area, and when the exposure process is performed corresponding to a large-area substrate, the number of shots in the exposure process increases, and thus the exposure process takes a long time. Problems required are pointed out.

Accordingly, there is a need for a technique for reducing the overlapping area in the first exposure process and the second exposure process to reduce the number of exposure processes and thereby shorten the exposure process time.

The present invention is to solve such a problem, and more particularly, an exposure apparatus capable of reducing the width of an overlapping area overlapping between the first exposure area and the second exposure area, thereby shortening the time of the entire exposure process; An object of the present invention is to provide an exposure method using the same.

According to the present invention, an overlapping area is created on a substrate on a stage by controlling the opening and closing of light from a light source introduced through a slit by the first shield unit. It is to provide an exposure apparatus capable of reducing the number of exposure steps corresponding to a large-scale model or an MMG model by reducing the overlapping width of regions.

In addition, the present invention includes the first exposure step, the overlapping area forming step, the secondary exposure step, and the overlapping area full exposure step, and the transfer direction of the first shield unit and the stage in the overlapping area forming step and the overlapping area full exposure step An exposure method capable of reducing the overlapping width of the overlapping area by controlling the same and differentially controlling the feed rate is provided.

According to the exposure apparatus and the exposure method using the same according to the present invention,

First, an overlapping area is generated in the first exposure area in which the shield unit and the stage are transported in the same direction. Since the width of the overlapping area can be reduced, the exposure process time can be reduced,

Second, by reducing the width of the overlapping area, the overlapping area is reduced, and the number of shots can be reduced by that amount.

Third, the width of the overlapping area can be adjusted by differently controlling the transport speed of the shield unit and the stage,

Fourth, through an accurate exposure process, there is an effect of remarkably improving the defect rate such as defective spots.

1 is a cross-sectional view schematically illustrating an exposure apparatus according to an embodiment of the present invention.
FIG. 2 is a reference diagram showing an exposure state of the first exposure area by the exposure apparatus shown in FIG. 1 .
FIG. 3 is a graph showing an exposure state of the first exposure area shown in FIG. 2 .
FIG. 4 is a reference diagram illustrating an exposure state in the case where the shield unit is slower than the stage in the exposure apparatus shown in FIG. 1 .
FIG. 5 is a reference diagram illustrating an exposure state when the shield unit is faster than the stage in the exposure apparatus shown in FIG. 1 .
FIG. 6 is a graph showing an overlap width according to a speed ratio between a shield unit and a stage of the exposure apparatus shown in FIG. 1 .
FIG. 7 is a reference diagram showing a state in which a large substrate is continuously exposed through the exposure apparatus shown in FIG. 1 .
8 is a flowchart illustrating an exposure method according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described so that those of ordinary skill in the art can easily implement them with reference to the accompanying drawings. It should be noted that the reference numbers indicated on the components in the accompanying drawings use the same reference numbers as much as possible when indicating the same components in other drawings. In addition, in describing the present invention, if it is determined that a detailed description of a related known function or a known configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted. In addition, certain features presented in the drawings are enlarged, reduced, or simplified for ease of description, and the drawings and their components are not necessarily drawn to scale. However, those skilled in the art will readily appreciate these details.

1 is a cross-sectional view schematically showing an exposure apparatus according to an embodiment of the present invention, FIG. 2 is a reference diagram illustrating an exposure state of a first exposure area by the exposure apparatus shown in FIG. 1, and FIG. 3 is FIG. It is a graph showing the exposure state of the 1st exposure area shown in FIG.

1 to 3 , an exposure apparatus 100 according to an embodiment of the present invention includes a light source 20 emitting an exposure beam to a substrate 10 , a first shield unit 110 , and a through hole 121 . ) includes a slit 120 formed therein, a stage 130 having a mask 30 and a glass substrate 10 , and an optical system 40 for refracting or reflecting light from the light source 20 .

The light source 20 emits a beam for exposure in the direction of the through hole 121 formed in the slit 120 , and may include a semiconductor laser or an ultraviolet lamp.

A first shield unit 110 is disposed below the light source 20 . The first shield unit 110 is provided with a guide portion such as an LM guide to reciprocate in the horizontal direction, and the first shield unit 110 reciprocates the upper portion of the slit 120 on the guide portion to reciprocate the through hole. (121) is selectively opened and closed. At this time, a second shield unit 210 is further disposed on the guide part, and the opening/closing operation of the through hole 121 is selectively performed.

The slit 120 is disposed below the first shield unit 110 or the second shield unit 210 . A through hole 121 through which the light of the light source 20 partially passes is formed in the slit 120 .

A mask 30 is disposed below the slit 120 . The mask 30 has a pattern formed on the substrate 10 , and a plurality of masks 30 may be provided according to the size or type of the pattern of the substrate 10 .

A substrate 10 is disposed below the mask 30 . The substrate 10 operates simultaneously with the mask 30 and is arranged to be driven in one stage 130 . The substrate 10 refers to a substrate 10 on which a thin film (a metal layer, an insulating film, a semiconductor layer, etc.) for patterning and a photoresist are laminated. The photoresist is patterned by transferring the pattern of the mask 30 through an exposure process, and then etching either the photoresist cured by the pattern of the mask 30 or the uncured photoresist. In this case, when the substrate 10 is larger than the mask 30 , a stitch exposure method of repeating the exposure process while moving the mask 30 may be used.

Here, one exposure process unit using the mask 30 is referred to as a shot, and an exposure area of the substrate 10 corresponding to one shot is referred to as a shot area. For example, as shown in FIG. 2 , an overlapping area is formed while the first shot is made, and conversely, when the second shot is made, the overlapping area is repeatedly exposed to complete exposure.

Referring to FIG. 3 , the first shot and the second shot and the degree of exposure to the overlapping area are expressed in a graph. Accordingly, the overlapping area is formed while gradually closing the through hole 121 as the first shield unit 110 is transported in the middle or at the starting point of the first shot, and in the middle or starting point of the second shot, the first shield unit ( 110) is transferred in the opposite direction to achieve full exposure.

FIG. 4 is a reference diagram illustrating an exposure state in the case where the shield unit is slower than the stage in the exposure apparatus shown in FIG. 1 .

Referring to FIG. 4 , it can be seen that the speed at which the stage 130 moves in the first direction (the right direction in the drawing) is different from the speed at which the first shield unit 110 moves in the first direction. In this case, the speed of the first shield unit 110 is slower than the speed of the stage 130 .

As the transfer of the stage 130 starts as shown in FIG. 4( a ), a fully exposed area is formed as a black part on the substrate 10 , and in FIG. 4( b ), the first shield unit 110 has a through hole 121 . is partially shielded to form a gray area on the substrate 10 and an incompletely exposed overlap area. And as shown in FIG. 4( c ), when the first shield unit 110 completely closes the through hole 121 , exposure is not performed on the substrate 10 , so that an unexposed area represented by a white portion is formed.

At this time, when the speeds of the first shield unit 110 and the stage 130 are the same, the first shield unit 110 and the stage 130 must be transported at a relatively fast or slow speed because an overlapping area is not formed. do.

FIG. 5 is a reference diagram illustrating an exposure state when the shield unit is faster than the stage in the exposure apparatus shown in FIG. 1 .

Referring to FIG. 5 , the speed at which the stage 130 moves in the first direction (the right direction in the drawing) and the speed at which the first shield unit 110 moves in the first direction are different from each other, and the first shield unit The speed of 110 represents a state that is faster than the speed of the stage 130 .

As the transfer of the stage 130 starts as shown in FIG. 5( a ), a complete exposure area is formed as a black part on the substrate 10 , and in FIG. 5( b ), the first shield unit 110 has a through hole 121 . is partially shielded to form a gray area on the substrate 10 and an incompletely exposed overlap area. And, as shown in FIG. 5C , when the first shield unit 110 completely closes the through hole 121 , exposure is not performed on the substrate 10 , so that an unexposed area represented by a white portion is formed.

FIG. 6 is a graph showing the overlapping width according to the speed ratio between the shield unit and the stage 130 of the exposure apparatus shown in FIG. 1 .

Referring to FIG. 6 , the correlation between the speed ratio and the overlap width between the first shield unit and the stage 130 is shown. The graph (G1) shows a state in which the speed of the first shield unit 110 is higher than the speed of the stage 130, and the graph (G2) shows that the speed of the first shield unit 110 is the speed of the stage 130. It shows a state that is slower than the speed.

In addition, the transport speed of the first shield unit 110 is adjusted to be about 0.3 times faster than the transport speed of the stage 130 and slower than the transport speed of the stage 130 , and also the transport of the first shield unit 110 . The speed is preferably controlled in a range that is faster than the feed speed of the stage 130 and slower than three times the feed speed of the stage 130 .

For example, assuming that the width of the through hole 121 is 100 mm, in order to reduce the overlap width to 100 mm or less, it is preferable to set the speed ratio of the first shield unit/stage to between about 0.5 and 2.

7 is a reference diagram illustrating a state in which a large substrate is continuously exposed through the exposure apparatus shown in FIG. 1 , and FIG. 8 is a flowchart illustrating an exposure method according to an embodiment of the present invention. Hereinafter, the same reference numerals as the aforementioned reference numerals denote the same components.

An exposure method using an exposure apparatus will be described in detail with reference to FIGS. 7 and 8 .

When exposing a large substrate step by step, complete exposure of the first exposure area is achieved through two shots. Accordingly, in order to fully expose the plurality of exposure areas, a plurality of shots are performed, and the process of forming overlapping areas in these shot areas is illustrated.

The exposure method using the exposure apparatus of the present invention consists of exposing the first exposure area (S100) and exposing the second exposure area (S200). Thereafter, repeated exposure is performed according to the size of the substrate.

The step of exposing the first exposure area (S100) includes the steps of first exposing the first exposure area (S110), forming the first overlapping area (S111), and performing secondary exposure of the first exposure area. and a step (S120).

The step of first exposing the first exposure area ( S110 ) corresponds to the 1st shot in FIG. 7 . At this time, while the stage 130 is transferred in the first direction, partial full exposure is performed.

At the same time, the step (S111) of forming the first overlapping region is performed. At this time, the first shielding unit 110 gradually shields the through hole 121 to form the first overlapping region. Then the 1st shot is completed.

The step of exposing the first exposure area for the second time ( S120 ) corresponds to the second shot in FIG. 7 . At this time, while the stage 130 moves in the second direction, the remaining portion of the first exposure area is completely exposed.

The step (S120) of exposing the first exposure area to secondary exposure includes the step of forming a second overlapping area (the n+1th overlapping area forming step of FIG. 9, S121) and the step of completely exposing the first overlapping area (S122). ) is included.

When the stage 130 is transferred in a second direction opposite to the first direction and the first shield unit 110 is transferred in the second direction at the same time, in the process of secondary exposure of the first exposure area, the second Two overlapping regions are formed. In this case, the first overlapping area corresponds to the second exposure area, and the process starts in a state in which the first exposure area and the second exposure area partially overlap. And when the first shield unit 110 completely opens the through hole 121, the remaining portion of the first exposure area is fully exposed, and when the substrate 10 reaches the first overlapping area, the second The shield unit 210 gradually shields the through hole 121 again, so that the first overlapping area is fully exposed.

Then, the complete exposure of the first exposure area is completed, and the second overlapping area of the second exposure area remains in a formed state.

After the step of exposing the first exposure area ( S100 ) is finished, the step of exposing the second exposure area ( S200 ) begins.

The step of exposing the second exposure area ( S200 ) includes the step of first exposing the second exposure area (the step of first exposing the n+1th exposure area of FIG. 8 , S210 ), and the second exposure area of the second exposure area. A secondary exposure step (secondary exposure of the n+1th exposure region of FIG. 8 , S220 ) is included.

The step of first exposing the second exposure area ( S210 ) includes a step of fully exposing the second overlapping area (a step of fully exposing the n+1th overlapping area of FIG. 8 , S211 ), and forming a third overlapping area and a step (forming an n+2 overlapping region, S212).

In the step of first exposing the second exposure area, the through hole 121 is gradually opened while the stage 130 and the second shield unit 210 are transferred in the first direction, and the second overlapping area is gradually exposed again to be completely exposure takes place Then, a portion of the second exposure area is fully exposed, and the first shield unit 110 is transported in the first direction to gradually shield the through hole 121 to form a third overlapping area.

Then, the second exposure of the second exposure area ( S220 ) begins. The step ( S220 ) of exposing the second exposure area for the second time includes a step of forming a fourth overlapping area ( S221 ) and a step of fully exposing the third overlapping area ( S222 ).

When the step (S220) of the second exposure of the second exposure area is started, the through hole 121 is gradually opened while the stage 130 and the first shield unit 110 are transferred in the second direction to open the fourth overlapping area. this is formed Then, a part of the second exposure area is fully exposed, and the second shield unit 210 is transferred again in the second direction to gradually shield the through hole 121 to fully expose the third overlapping area.

Accordingly, complete exposure of the second exposure area is completed in a state in which the fourth overlapping area is formed.

Since the exposure process is performed by repeating the subsequent process in the same manner as in the above-described method, a redundant description will be omitted.

Additionally, the stage 130, the first shield unit 110, and the second shield unit 210 are transported in the same direction, but may be transported in different directions in some cases. Also, the first shield unit 110 and the second shield unit 210 may be integrally formed to operate in conjunction.

And if the speed between the stage 130 and the first shield unit 110 or the second shield unit 210 is controlled, the overlap width can be adjusted according to the following conditions. When the speed of the first shield unit 110 or the second shield unit 210 is slower than the speed of the stage 130, the overlapping width of the overlapping area is "(width of the hole * stage speed)/shield unit speed) -The width of the hole)" is determined by the formula.

In addition, when the speed of the first shield unit 110 is faster than the speed of the stage 130, the overlapping width of the overlapping area is determined by the formula "(width of hole*stage speed)/speed of shield unit".

Therefore, if the overlapping width of the overlapping area is reduced, the number of shots in the exposure area can be reduced, thereby reducing the time required for the exposure process as a whole, and also having the effect that the exposure process can be applied to a large model. In addition, the effect of reducing the defect rate such as stain defects can be expected.

In the above, specific embodiments have been described with reference to the drawings to illustrate the technical idea of the present invention, but the present invention is not limited to the same configuration and effects as the specific embodiments as described above, and various modified examples are the scope of the present invention. It can be carried out within the limit that does not deviate from Accordingly, such modifications should also be considered to fall within the scope of the present invention, and the true technical protection scope of the present invention should be determined by the technical spirit of the claims to be described later.

100: exposure device
110: first shield unit 111: second shield unit
120: slit 121: through hole
130: stage
10: substrate 20: light source
30: mask 40: optical system

Claims (12)

a slit provided with a hole through which the light of the light source is transmitted;
a first shield unit interposed between the light source and the slit to selectively open and close the through hole so that the light of the light source passes or blocks the through hole;
a stage disposed below the slit and including a mask for patterning the light passing through the through hole, and a substrate driving in the same direction as the mask; and
an optical system that refracts the light passing through the mask and irradiates light in a set region on the substrate; including,
The transfer direction of the first shield unit is the same as the transfer direction of the stage,
and the mask includes a pattern transferred to the substrate by the light passing through the through hole of the slit. The method according to claim 1,
The exposure apparatus for transferring the first shield unit at a different feed rate than the stage. 3. The method according to claim 2,
The exposure apparatus in which the transport speed of the first shield unit is set to be faster than 0.3 times the stage transport speed and slower than the stage transport speed. 3. The method according to claim 2,
The exposure apparatus in which the transport speed of the first shield unit is set faster than the stage transport speed and slower than three times the stage transport speed. The method according to claim 1 or 2,
and a second shield unit that is spaced apart from the first shield unit by a set interval and selectively opens and closes so that the light of the light source passes or blocks the through hole. 6. The method of claim 5,
The second shield unit is an exposure apparatus in which an opening/closing operation is controlled simultaneously with or separately from the first shield unit. The method according to claim 1,
When the transfer direction of the stage and the transfer direction of the first shield unit move in the same direction and move at different speeds, the width of the overlapping area exposed on the substrate is smaller than the width of the through hole. performing primary exposure on a portion of a first exposure area while a stage including a mask including a pattern and a substrate is transferred in a first direction;
A first shield unit that selectively shields the light source in the middle or at the starting point of the first exposure step is transferred in the first direction, and the first shield unit and the stage block the through hole through which the light of the light source passes at different speeds, , exposing the incompletely exposed first overlapping area to the first exposure area;
performing secondary exposure on the remaining portion of the first exposure area while the stage is transported in a second direction opposite to the first direction;
transferring the first shield unit in a second direction in the middle or at a starting point of the second exposure step, the first shield unit and the stage shielding the through hole, and completely exposing the first overlapping area;
An exposure method comprising a. 9. The method of claim 8,
In the step of completely exposing the first overlapping region, the exposure method includes transferring the first shield unit and the stage in the second direction at the same speed ratio as the transfer in the first direction. 9. The method of claim 8,
The second exposure of the first exposure area includes:
and exposing an n+1th overlapping area prior to exposing the first overlapping area completely. 9. The method of claim 8,
When the speed of the first shield unit is slower than the speed of the stage in the step of exposing the incompletely exposed first overlapping area or in the step of fully exposing the first overlapping area,
The overlapping width y1 of the first overlapping region is
The exposure method determined by the formula of "y1=((width of aperture*stage speed)/speed of first shield unit)-width of aperture". 9. The method of claim 8,
When the speed of the first shield unit is faster than the speed of the stage in the step of exposing the incompletely exposed first overlapping area or in the step of fully exposing the first overlapping area,
The overlapping width y2 of the first overlapping area is an exposure method determined by the formula of "y2=(width of hole*stage speed)/first shield unit speed".

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