JPH06252028A - Inert gas purge mechanism of proximity exposure device - Google Patents

Abstract

PURPOSE:To provide the inert gas purge mechanism of a proximity exposer which can lower the concentration of oxygen inside processing space enough. CONSTITUTION:Below a mask holder 3, which holds a mask 2, gas jet mechanisms 10a, 10b, 20a, and 20b, which jet nitrogen gas into the processing space between a mask 2 and a substrate 4, and others are arranged on four sides around a board 4. A shutter mechanism 30 is arranged between the processing space and a temperature-controlled air discharge port 8. The shutter mechanism 30 change the condition of intercepting the air jet out of the temperature-controlled air discharge port 8 flowing into the processing space by rocking screen boards 31 a and 31b by the command of a controller and the condition of allowing it over to each other. The shutter mechanism 30 is closed from the start of jet of nitrogen gas to the end of exposure, and the air from the temperature-controlled air discharge port 8 does not flow into the processing chamber.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a method of exposing a square glass substrate coated with a photosensitizer, for example, a rectangular glass substrate for a liquid crystal display, to a mask in an environmental chamber to expose the square glass substrate.
The present invention relates to an inert gas purging mechanism of a proximity exposure apparatus that purges the space between the mask and the substrate into an atmosphere of an inert gas such as nitrogen when the pattern of the mask is printed on the photosensitive agent applied to the substrate.

[0002]

2. Description of the Related Art When a substrate having a surface coated with a certain type of photosensitizer (for example, a negative type color filter resist) is exposed in air, the photosensitizer reacts with oxygen contained in the air to form a pattern. It is known that the printing resolution of is deteriorated. In order to deal with such a problem, conventionally, exposure of a substrate coated with this type of photosensitive agent is performed as follows.

First, as a first method, an oxygen blocking film is applied on a film of a photosensitizer to prevent the occurrence of oxygen polymerization during exposure. However, this method has a problem that the number of steps for applying the oxygen barrier film on the film of the photosensitizer increases.

Therefore, as a second method, a method of purging a space between the substrate and the mask (hereinafter, referred to as "processing space") into an atmosphere of an inert gas such as nitrogen during exposure is implemented. This will be described with reference to FIG. FIG. 12 is a sectional view showing a schematic configuration of an inert gas purging mechanism of a proximity exposure apparatus according to a conventional example.

As shown in the figure, a mask 2 is supported by a mask holder 3 below the exposure optical system 1. The substrate 4 is supported by a vertically movable stage 5, and the substrate 4 is configured to be able to move close to the mask 2. Reference numeral 6 indicates a slit for ejecting an inert gas into the processing space between the mask 2 and the substrate 4. It should be noted that this slit 6 is formed on the substrate 4 as shown in the figure.
In addition to arranging on two opposite sides of
It may be arranged only on the side, or may be arranged on all four sides of the substrate 4.

Then, with the substrate 4 and the mask 2 at a predetermined interval, an inert gas is jetted from the slit 6 to discharge oxygen in the processing space, and the jetted inert gas creates an inert gas atmosphere in the processing space. Replace. When the processing space is purged with an inert gas, light is emitted from the exposure optical system 1,
The pattern of the mask 2 is printed on the photosensitive agent applied to the substrate 4.

By the way, in order that the above-mentioned exposure processing can be performed at a predetermined temperature and in a state kept in a clean environment, a proximity exposure apparatus generally has an environment chamber 7 as shown in FIG. It is contained. Then, the air having a predetermined temperature ejected from the temperature-controlled air ejection port 8 flows as shown by the alternate long and short dash line in the figure and is exhausted from the exhaust port 9, thereby adjusting the temperature in the chamber 7 and dust. Etc. to keep in a clean environment.

[0008]

However, the conventional example having such a structure has the following problems. That is, when the proximity exposure apparatus is housed in the environmental chamber 7 as shown in FIG. 13, an inert gas is ejected from the slit 6 and the temperature control air ejection port 8 is ejected while the processing space is replaced with an inert gas atmosphere. Since the jetted air flows into the processing space, there is a problem that the oxygen concentration in the processing space does not sufficiently decrease.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an inert gas purging mechanism for a proximity exposure apparatus capable of sufficiently reducing the oxygen concentration in the processing space. And

[0010]

The present invention has the following constitution in order to achieve such an object. That is, the present invention, in the environmental chamber, by exposing the substrate coated with the photosensitizer close to the mask, and exposing the pattern drawn on the mask to the photosensitizer coated on the substrate, In an inert gas purging mechanism of a proximity exposure apparatus that purges a space between the substrate and the mask (hereinafter, referred to as a "processing space") with an inert gas, an inert gas that ejects an inert gas into the processing space. Gas ejecting means, gas flow interrupting means for temporarily interrupting the air ejected from the temperature control air ejecting port provided in the environmental chamber from flowing into the processing space, and the inert gas ejecting means. During the period from the start of the ejection of the inert gas by the process to the end of the exposure, the gas flow blocking is performed so as to block the flow of the air jetted from the temperature control air jet into the processing space. And control means for controlling the means, those provided with.

[0011]

The operation of the present invention is as follows. That is,
The control means, before the start of the inert gas jetting by the inert gas jetting means, a gas so as to block the air jetted from the temperature control air jet port provided in the environmental chamber from flowing into the processing space. Control the flow blocking means. Next, the inert gas is jetted by the inert gas jetting means, the inside of the processing space is purged with the inert gas, and in this state, the pattern of the mask which is exposed and exposed is printed on the photosensitive agent applied to the substrate. Meanwhile, the gas flow blocking means prevents the air ejected from the temperature-controlled air ejection port from flowing into the processing space. When the exposure is completed, the control means returns the original state by controlling the gas flow blocking means, that is, the state in which the air ejected from the temperature control air ejection port is allowed to flow into the processing space. .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In the present embodiment, nitrogen gas (N
_The inert gas purging mechanism according to the present invention will be described based on the nitrogen purging mechanism of the proximity exposure apparatus using ₂ ). 1 is a plan view showing a configuration of a nitrogen purging mechanism of a proximity exposure apparatus according to this embodiment, FIG. 2 is a sectional view taken along the line AA of FIG. 1, and FIG. 3 is a section taken along the line BB of FIG. FIG. Note that FIG.
2 and FIG. 13 have the same configurations as those in the conventional example, and thus detailed description thereof will be omitted. However, each figure,
Also, in the following figures, the exposure optical system is omitted.

In the present embodiment, as shown in the figure, a shutter mechanism 30 that temporarily blocks the air ejected from the temperature control air ejection port 8 from flowing into the processing space between the mask 2 and the substrate 4. Is provided. This shutter mechanism 30
The configuration will be described with reference to FIGS. 2 and 3.

The shutter mechanism 30 includes a shield plate 31.
A state in which the air ejected from the temperature control air ejection port 8 is blocked from flowing into the processing space by swinging a and 31b around the rotation shafts 32a and 32b (hereinafter, referred to as
"Closed state" and a state in which the air from the temperature control air ejection port 8 is allowed to flow into the processing space (hereinafter,
It is configured to be able to switch between "open state").

That is, the shielding plates 31a and 31b are fixed to the rotary shafts 32a and 32b, respectively. One end of a swinging member 34a is connected to the tip of a rod 33a of an air cylinder 33 fixed to the floor, and one end of a rotating shaft 32a is connected to the other end of the swinging member 34a. ing. The rotating shaft 32a is rotatably attached to a member (not shown) fixed to the base together with the rotating shaft 32b. A swing member 34b is connected to the other end of the rotating shaft 32a. Further, the swinging member 34 b and the swinging member 34 c connected to one end of the rotating shaft 32 b on which the shield plate 31 b is fixed are connected via a connecting member 35. By expanding and contracting the rod 33a of the air cylinder 33, the swing member 34a rotates the rotary shaft 32a at that position, and in conjunction with this, the swing member 34b, the connecting member 35, and the swing member 34c are used. The rotation shaft 32b is also rotated at that position, and accordingly, the closed state and the open state of the shield plates 31a and 31b are interlocked and switched. The shutter mechanism 30 corresponds to the gas flow blocking means in the present invention.

The switching of the shield plates 31a and 31b between the open state and the closed state, that is, the expansion and contraction of the rod 33a of the air cinder 33 is performed by the control unit 40 as shown in FIG.
Is configured to be controlled by. In addition to switching between the open and closed states of the shield plates 31a and 31b, the control unit 40 moves up and down the stage 5, switches the ejection of nitrogen from a slit described later, and performs exposure by the exposure optical system 1. It is also configured to perform control such as switching between start and stop.

The control unit 40 is composed of a microcomputer including, for example, a CPU (central processing unit) 41, a memory 42, a ROM (read only memory) 43, and the like. The ROM 43 pre-stores a processing procedure (program) for each unit as described later, and the CPU 41 executes the processing in accordance with the program. In the figure, reference numeral 44 is the CPU 41 and the memory 4.
2, a bus for connecting the ROM 43 and the like, and reference numeral 4
Reference numeral 5 denotes an I / O interface that connects the CPU 41 to the air cylinder 33, the stage 5, and the like. The control section 40 corresponds to the control means in the present invention.

Next, the arrangement and structure of the gas ejection mechanism as the inert gas ejection means attached to this embodiment will be described with reference to FIGS. 1, 5 and 6. 5 is a sectional view taken along the line CC of FIG. 1, and FIG. 6 is a sectional view taken along the line DD of FIG.

As shown in the figure, four gas ejection mechanisms 10a, 10b, 10c and 10d each having a slit for ejecting nitrogen gas are provided below the mask holder 3 along the four sides of the substrate 1, respectively. It is installed. A gas ejection mechanism 10a arranged to face each other along the long side of the substrate 1,
At the lower part of 10b, another gas ejection mechanism 20a, 20b having a slit for ejecting nitrogen gas is attached. The operation of each of the gas ejection mechanisms 10a to 10d and the gas ejection mechanisms 20a and 20b will be clarified in the operation description described later.

Since the gas ejection mechanisms 10a to 10d and the gas ejection mechanisms 20a and 20b have basically the same configuration, the configuration will be described here by taking the gas ejection mechanism 10a as an example. The gas ejection mechanism 10a has a rectangular tube shape with both ends closed, and nitrogen gas is supplied to the inside from nozzles 11 (see FIG. 1) arranged near the both ends. The supply / cutoff of nitrogen gas to the gas ejection mechanism 10a and the flow rate thereof are controlled by the control unit 40 described above via the opening / closing control valve 17 and the flow rate control valve 18 (see FIG. 4). The nitrogen gas supplied from the nozzle 11 into the gas ejection mechanism 10a is dispersed by the baffle 12, passes through the current plate 13 having a large number of holes, and is ejected through the slit 14. At this time, the slit 14
The nitrogen gas is jetted obliquely upward by the action of the member 15 at the lower part of the. In addition, as shown in FIG. 1, in the connecting portion of the gas ejection mechanisms 10a to 10d,
A shielding member 16 for preventing the inflow of air between the substrate 4 and the mask 2 is provided.

Next, the procedure of the exposure processing by the proximity exposure apparatus having the above-mentioned structure will be described with reference to the flowchart shown in FIG.

First, the rod 33 of the air cylinder 33
a is extended to close the shielding plates 31a and 31b (step S1). Next, the stage 5 holding the substrate 4
Is raised to a predetermined position (step S2). This predetermined position is a position where the substrate 4 faces the slits of the gas ejection mechanisms 10a to 10d, and is a position where the ejection of nitrogen gas is started. The operations of steps S1 and S2 described above may be started simultaneously, or the operation of step 2 may be started first. The point is that the shielding plates 31a and 31b are closed before starting the ejection of the nitrogen gas so that the air ejected from the temperature control air ejection port 8 does not flow into the processing space. .

With the shielding plates 31a, 31b closed and the substrate 4 raised to a predetermined position, the gas ejection mechanisms 10a, 10b are arranged opposite to each other along the long side of the substrate 4.
Of the nitrogen gas is started at the same time, and the nitrogen gas is jetted from the gas jetting mechanisms 20a and 20b (step S).
3). As shown in FIG. 1, the flow velocity distribution of the nitrogen gas jetting in the gas jetting mechanisms 10a and 10b is adjusted so that the flow velocity at the central portion of the slit is faster than the flow velocity at both ends. This flow velocity distribution shows the gas ejection mechanism 10a,
Structure of baffle 12 and baffle plate 13 provided inside 10b
Density of holes drilled in the substrate, and nitrogen gas supply nozzle 1
It can be realized by adjusting the position 1 and the supply amount of nitrogen gas. In the present embodiment, as described above, the nozzle 11 is provided near both ends of the gas ejection mechanisms 10a and 10b, the baffle 12 has a uniform structure, and the current plate 13 is provided.
The density of the holes drilled in was also uniform. Then, as shown in the measurement result of FIG. 8, the above flow velocity distribution is realized by setting the supply flow rate to 50 NL / min. Note that FIG.
The measurement result shown in is the nitrogen gas flow rate from the slit is 30
It shows the result of measuring the flow rate of nitrogen gas at each flow rate at each measurement point where the slit is divided into 9 equal parts, while changing the injection rate to NL / min, 40 NL / min, 50 NL / min. In the figure, R ₃₀
Shows a flow velocity distribution when nitrogen gas is ejected at a flow rate of 30 NL / min, and R ₄₀ shows a flow velocity distribution of ₄₀ NL / min and R ₅₀ shows a flow velocity distribution of ₅₀ NL / min.

The nitrogen gas is ejected from the gas ejecting mechanisms 10a and 10b at the same time as the nitrogen gas is ejected from the gas ejecting mechanisms 10a and 10b. This is because the generated nitrogen gas does not entrap the air around it. This makes it possible to supply pure nitrogen gas into the processing space.

The gas ejection mechanisms 10a and 10 as described above.
The ejection of nitrogen gas from b, 20a, and 20b is continued for a predetermined time (for example, 4 seconds). As a result, a pure nitrogen atmosphere is formed near the central portion between the upper surface of the substrate 4 and the lower surface of the mask 2. Then, after a lapse of a predetermined time for forming this pure nitrogen atmosphere, the stage 5 is further raised to hold the substrate 4 and the mask 2 close to a predetermined gap (10 μm to 200 μm) (step S4). ). As a result, the pure nitrogen atmosphere formed near the central portion between the upper surface of the substrate 4 and the lower surface of the mask 2 is crushed, and the pure nitrogen atmosphere is spread from the central portion to the periphery. Along with this diffusion, oxygen between the upper surface of the substrate 4 and the lower surface of the mask 2 is pushed to the outside and discharged to the outside.

Next, the ejection of nitrogen gas from the gas ejection mechanisms 20a and 20b is stopped, and the nitrogen gas is ejected at 30 NL / min from each of the gas ejection mechanisms 10a to 10d installed along the four sides of the substrate 4. Eject (step S5). As a result, a curtain of nitrogen gas is formed around the nitrogen atmosphere formed between the upper surface of the substrate 4 and the lower surface of the mask 2 up to step S4 to block the inflow of air (oxygen) from the outside. The state of nitrogen atmosphere can be maintained. The double-dashed line arrow in FIG. 6 indicates the outflow state of the nitrogen gas in step S5. In this state, in order to print the pattern drawn on the mask 2 on the photosensitive agent applied on the upper surface of the substrate 4, the exposure optical system 1 exposes the mask 2 from above (step S6). When the exposure is completed, the ejection of nitrogen gas from each of the gas ejection mechanisms 10a to 10d is stopped (step S7), and the shield plates 31a and 31b are opened (step S8).

In the above embodiment, the gas ejection mechanism 1
In order to prevent the entrainment of air during the nitrogen purging using 0a and 10b, the gas ejection mechanisms 20a and 20b are individually provided. For example, as shown in FIG. The rising position of the stage 5 may be appropriately set so that the jetted nitrogen gas flows out between the substrate 4 and the mask 2 and in both directions below the substrate 4. In this way, the nitrogen gas flowing out toward the lower side of the substrate 4 can prevent the inflow of air between the substrate 4 and the mask 2 due to the entrainment of air, so that a curtain of nitrogen gas is formed. Gas ejection mechanism 20a,
It is not always necessary to provide 20b.

Further, in the above embodiment, the gas ejection mechanism 1
Although 0a to 10d, 20a and 20b are provided and nitrogen purging is performed by the procedure as described with reference to FIG. 5, the inert gas jetting means in the present invention is not limited to such a configuration and, for example, nitrogen gas may be used. Slits, nozzles, etc. for ejecting the gas may be arranged on only one predetermined side of the substrate 4, or may be arranged on two opposite sides of the substrate 4, and the nitrogen purging procedure is also applicable. It need not be the one described in the flowchart of FIG. Even when nitrogen purging is performed by the inert gas ejecting means having such a configuration, if the gas flow blocking means (shutter mechanism 30) is provided, the temperature controlled air ejection port is provided in the nitrogen atmosphere formed by the nitrogen purging. Since the air jetted from the nozzle 8 is prevented from flowing in, it is possible to avoid the problem that the oxygen concentration in the processing space is lowered by the air from the temperature control air nozzle 8.

Further, in the above-mentioned embodiment, the shutter mechanism 30 is provided as the gas flow blocking means, but the air jetted from the temperature control air jet port 8 is temporarily shut off from flowing into the processing space. If so, the configuration of the gas flow blocking means is not limited to this. Therefore, for example, as shown in FIG. 10, by using the drive mechanism such as the air cylinder 51 between the temperature control air ejection port 8 and the processing space, the shield plate 50 as the gas flow blocker is moved up and down, A state in which the air ejected from the temperature-controlled air ejection port 8 is blocked from flowing into the processing space (two-dot chain line in FIG. 10) and the air from the temperature-controlled air ejection port 8 flows into the processing space. It may be configured to be able to switch between the permitted state (solid line in FIG. 10). Further, as shown in FIG. 11, a shield plate 60 that can be opened and closed is provided at the temperature regulator jet port 8 so that the air jetted from the temperature control air jet port 8 enters the processing space by the opening / closing operation of the shield plate 60. A configuration in which it is possible to switch between a state in which the inflow is blocked (two-dot chain line in FIG. 11) and a state in which the air from the temperature control air ejection port 8 is allowed to flow into the processing space (solid line in FIG. 11) You may.

[0030]

As is apparent from the above description, according to the present invention, from the start of the ejection of the inert gas by the inert gas ejection means to the end of the exposure, the gas flow blocking means is used to protect the environmental chamber. Since the air blown out from the temperature control air outlet provided inside the processing space is configured to be blocked from flowing into the processing space, the temperature control air outlet is added to the inert gas atmosphere formed in the processing space. Since air from the inside is prevented from flowing in, the oxygen concentration in the processing space can be sufficiently reduced.

[Brief description of drawings]

FIG. 1 is a plan view showing a configuration of a nitrogen purging mechanism of a proximity exposure apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG.

FIG. 3 is a view taken along the line BB of FIG.

FIG. 4 is a diagram showing a configuration of a control unit.

5 is a sectional view taken along the line CC of FIG.

6 is a sectional view taken along the line DD of FIG.

FIG. 7 is a flowchart showing a procedure of exposure processing by the apparatus of the embodiment.

FIG. 8 is a diagram showing a flow velocity distribution of nitrogen gas from a purge slit.

FIG. 9 is a view showing a modified example of the inert gas jetting means.

FIG. 10 is a diagram showing a configuration and an operation of a modified example of the gas flow blocking means.

FIG. 11 is a diagram showing the configuration and operation of a modified example of the gas flow blocking means.

FIG. 12 is a sectional view showing a schematic configuration of an inert gas purging mechanism of a proximity exposure apparatus according to a conventional example.

FIG. 13 is a cross-sectional view showing a state in which the conventional device is housed in an environmental chamber.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Exposure optical system 2 ... Mask 4 ... Substrate 5 ... Stage 7 ... Environmental chamber 8 ... Temperature control air ejection port 10a-10d ... Gas ejection mechanism (inert gas ejection means) 20a, 20b ... Gas ejection mechanism (inert gas) Jetting means) 30 Shutter mechanism (gas flow blocking means) 40 Control unit (control means) 50, 60 Shielding plate (gas flow blocking means)

Claims (1)

[Claims] 1. When printing a pattern drawn on the mask onto the photosensitive agent applied to the substrate by exposing the substrate coated with the photosensitive agent to a mask in an environmental chamber, the substrate is exposed. In an inert gas purging mechanism of a proximity exposure apparatus for purging a space between a substrate and the mask (hereinafter, referred to as a "processing space") with an inert gas, an inert gas for ejecting an inert gas into the processing space. The jetting means, the gas flow blocking means for temporarily blocking the air jetted from the temperature control air jet provided in the environmental chamber from flowing into the processing space, and the inert gas jetting means. The gas flow blocking means for blocking the air jetted from the temperature control air jet from flowing into the processing space from the start of the jetting of the inert gas to the end of the exposure. An inert gas purging mechanism for a proximity exposure apparatus, comprising: