JPH11102888A - Substrate processing vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a processing solution from flowing from its level towards a substrate and to improve nonuniformity in flow velocity distribution. SOLUTION: A pair of covers 12, extending along the total length of a vessel body 1, are provided on the upper portion of the body 1. Both covers 12 are arranged in such a manner that their bottom surfaces come in contact with the processing solution, and that one end of each cover comes in intimate contact with the upper vertical wall surface of the body 1. An overflow port 14 is formed between the other ends of the covers 12, i.e., above the center of a substrate 2 accommodated in the body 1. The port 14 limits the position and area of an upper opening 13 of the body 1. As a result, the processing solution which rises towards the upper portion of the body 1 along the substrate 2 is discharged, while it is caused to flow along the bottom surfaces of the covers 12 so as to concentrate on the port 14, thereby preventing the processing solution from returning towards the substrate 2 from the upper portion of the body 1 and suppressing, the flow velocity difference between above and below the substrate 2, and making the flow velocity distribution uniform.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer, a glass substrate for liquid crystal, a substrate for manufacturing electronic parts such as a mask and a photomask, and the like. And a substrate processing tank for processing the substrate by immersing the substrate in a processing liquid.

[0002]

2. Description of the Related Art A substrate processing tank of this type is generally constructed as shown in a cross-sectional view of FIG. That is, the processing liquid supply pipes 02 are provided on both sides of the bottom of the tank main body 01, and the processing liquid is supplied toward the center side of the tank main body 01, such as downward, at a predetermined interval in the longitudinal direction of the processing liquid supply pipe 02. A supply slit 03 is provided, a processing liquid is supplied into the tank main body 01, and the substrate 04 stored in a vertical posture is immersed in the processing liquid for processing.

The processing liquid supplied from both sides of the bottom into the tank body 01 joins below the center of the substrate 04 and rises along the plate surface of the substrate 04 from there.
At the liquid level, head toward the upper outer periphery of the tank
1, overflows from the upper opening 05, flows into the overflow tank 06, and is discharged.

[0004]

However, in the case of the conventional example, some of the processing liquid that has reached the upper outer peripheral edge of the tank main body 01 at the liquid level does not overflow, and the processing liquid reaches the inner peripheral surface of the vertical wall of the tank main body 01. There was a problem of flowing downward along. As a result, there are drawbacks in that particles separated from the substrate 04 are mixed in, the gas is dissolved at the liquid surface portion, or the processing liquid containing the bubbles and particles acts on the substrate 04, thereby causing contamination of the substrate 04.

[0005] Further, the viscous resistance received from the substrate 04 is large at the portion flowing along the substrate 04, and the flow resistance at the portion flowing along the substrate 04 is determined by the edge of the substrate 04 and the tank body 01.
Is greater than the flow resistance at the point between the vertical wall. For this reason, the processing liquid rising from the lower side of the center of the substrate 04 becomes a flow branched to the vertical wall side of the tank main body 01 having a small resistance, and the flow velocity of the processing liquid at a location flowing along the substrate 04 decreases. . As a result, a difference in flow velocity occurs between the upper side and the lower side of the substrate 04, and the flow velocity distribution of the processing liquid over the entire substrate 04 becomes non-uniform.
When changing the type, such as chemical to pure water or pure water to chemical, or when transferring and processing substrates from a chemical tank to a pure water rinsing tank or a pure water rinsing tank to the chemical tank, the replacement time is reduced. As a result, the amount of the chemical solution or pure water used increases, which is uneconomical.

The present invention has been made in view of such circumstances, and has as its object to prevent a processing liquid from flowing from a liquid level to a substrate side and to improve non-uniformity of flow velocity distribution. I do.

[0007]

The present invention has the following configuration in order to achieve the above object. That is, the invention according to claim 1 includes a tank body for immersing a substrate stored in a vertical posture with a processing liquid, a processing liquid supply unit for supplying a processing liquid to the substrate stored in the tank body. In a substrate processing tank for processing a substrate by causing a processing liquid to overflow from an upper opening of the tank main body, the processing liquid supply unit is provided at a bottom of the tank main body, and is disposed along a plate surface of the substrate. A cover forming an overflow port having a limited area of the upper opening is provided in a state where the lower surface thereof is in contact with the processing liquid, and the cover is provided with the lower surface being treated. It is characterized in that it is displaceably provided at a closed position in contact with the liquid and an open position retracted from above the tank body.

[0008] The invention described in claim 2 is the first invention.
Wherein the overflow ports are formed at both ends of the upper portion of the tank body in a state where the cover is in the closed position.

[0009] The invention described in claim 3 is the first invention.
Wherein the overflow port is formed in an upper part of the tank body above the center of the substrate housed in the tank body, with the cover being in the closed position. It is.

[0010]

The operation of the present invention is as follows. That is,
According to the first aspect of the present invention, the processing liquid supplied from the processing liquid supply unit provided at the bottom of the tank body is collected on the overflow port side where the position and area of the upper opening of the tank body are limited by the cover. The processing liquid is discharged to prevent the processing liquid from flowing from the upper part of the tank body back to the substrate side. Also,
The flow velocity at the upper part of the tank body becomes higher than before due to the flow gathered at the overflow port side, suppressing the flow velocity difference between the upper and lower sides of the substrate and making the flow velocity distribution uniform. When the substrate is taken in and out of the tank body, the cover is displaced to the open position retracted from above the tank body so as not to be obstructed by the cover.

According to a second aspect of the present invention, the processing liquid which rises along the substrate to the upper portion of the tank main body overflows on both sides of the upper portion of the tank main body formed at both ends of the upper portion of the tank main body. The processing liquid is discharged so as to collect at the mouth side, and the processing liquid is prevented from flowing from the upper part of the tank body back to the substrate side. In addition, by being dragged by the flows gathering on the overflow ports on both sides of the upper portion of the tank body, the flow velocity above the substrate is increased, the flow velocity difference between the upper and lower sides of the substrate is suppressed, and the flow velocity distribution is made uniform.

[0012] According to a third aspect of the present invention, the processing liquid which is raised to the upper portion of the tank main body along the substrate is placed on the upper portion of the tank main body above the center of the substrate contained in the tank main body. The processing liquid is discharged so as to collect at the formed overflow port side, thereby preventing the processing liquid from flowing from the upper part of the tank body back to the substrate side. In addition, by being dragged by the flow collected on the overflow port side above the center of the substrate at the top of the tank body, the flow velocity above the substrate is increased, the flow velocity difference between the top and bottom of the substrate is suppressed, and the flow velocity distribution is uniform. Become

[0013]

Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a first embodiment of a substrate processing tank according to the present invention, and FIG. 2 is a plan view of the first embodiment. As shown in FIGS. 1 and 2, the substrate processing tank includes a tank main body 1 and a lifter 3 that stores and removes the substrate 2 in and from the tank main body 1.

The lifter 3 integrally connects three substrate holding members 5 each having a substrate holding groove 4 for holding the substrate 2 in a vertical posture at a predetermined pitch in the longitudinal direction, and one longitudinal end of the substrate holding member 5. A connecting member 6 to be connected, a substrate elevating member 7 integrally connected to the other end of the substrate holding member 5 in the longitudinal direction, and an elevating device 8 installed outside the tank body 1 and connected to the substrate elevating member 7 in an interlocked manner. It is configured.

Inside the tank body 1, processing liquid supply units 9 each formed of a double quartz tube are provided on both sides of the bottom. Although not shown, a processing liquid supply pipe is connected to the processing liquid supply section 9, and a chemical liquid such as an etching liquid or pure water is selected as the processing liquid by a switching configuration on the upstream side of the processing liquid supply pipe. It can be supplied.

An outer tube 9a constituting the processing liquid supply unit 9 includes:
In a plan view, the slits 10 are formed so as to supply the processing liquid downward at a predetermined pitch in the tube axis direction so as to be located between the substrates 2 arranged in parallel. As a result, the processing liquid is supplied from the processing liquid supply units 9 on both sides toward the lower side of the center of the substrate 2, and the supplied processing liquids join at the lower side of the center of the substrate 2, and then upward. The flow is to immerse the substrate 2 in the processing liquid.

An overflow tank 11 is provided so as to surround the periphery of the upper end of the tank body 1, and is configured to receive and discharge the processing liquid overflowing from the tank body 1.

A pair of covers 12 are provided on the upper part of the tank body 1 over the entire length of the tank body 1 in the longitudinal direction. Both covers 12 are provided such that the lower surfaces thereof are in contact with the processing liquid and one side edge is in close contact with the upper portion of the vertical wall surface of the tank body 1. An overflow port 14 in which the position and area of the upper opening 13 are limited is formed. The overflow port 14 extends over the entire length of the tank body 1 in the upper part of the tank body 1 and above the center of the substrate 2 housed in the tank body 1. The cover 12 may be made of any material as long as it has durability with respect to the processing liquid to be used.

On both sides of the overflow tank 11,
A pair of support arms 15 is attached so as to be swingable around the longitudinal axis of the tank body 1, and a cover 12 is attached to the support arm 15. And the open position retracted from above the tank body 1 so that the substrate 2 can be easily taken in and out of the tank body 1.

The upper surface of each of the covers 12 is formed as an inclined surface (the inclination angle is about 2 °) slightly lower toward the overflow tank 11 in the closed position, and the processing discharged from the overflow port 14 is performed. The liquid is easy to flow to the overflow tank 11 side.

With the above arrangement, the processing liquid which is raised to the upper part of the tank body 1 along the substrate 2 is caused to flow along the lower surface of the cover 12, and is stored in the tank body 1 above the tank body 1. The processing liquid is flowed so as to gather at an overflow port 14 formed above the center of the substrate 2, and the processing liquid
Is discharged from the overflow port 14 while preventing it from returning to the substrate 2 side from above. Further, the flow velocity is increased above the substrate 2 by being dragged by the flow gathering on the overflow port 14 side, the flow velocity difference between the upper and lower sides of the substrate 2 is suppressed, and the flow velocity distribution is made uniform.
Reduce the processing time of the processing solution replacement.

According to the first embodiment, since the processing liquid is collected and discharged at a position above the center of the substrate 2, the flow which receives the most resistance and rises along the center of the substrate 2 and a position near the center is drawn. And the flow velocity difference between the top and bottom of the substrate 2 can be effectively reduced, and the flow velocity distribution can be made uniform.

The displacement of the cover 12 may be performed by an independent drive unit. However, the cover 12 is moved to the closed position in accordance with the operation of the elevating device 8 as the substrate 2 is lowered into the tank body 1. The cover 12 is preferably displaced to the open position as the substrate 2 is lifted and taken out of the tank body 1.

FIG. 3 is a cross-sectional view showing a second embodiment of the substrate processing tank according to the present invention. The difference from the first embodiment is as follows.

In the closed position, the opposing edges of the two covers 12 are brought into close contact with each other by the step 21, and between the other edge of each of the two covers 12 and the upper part of the vertical wall of the tank body 1, that is, the tank body 1 An overflow port 22 that limits the position and area of the upper opening 13 of the tank main body 1 is formed at each of both upper ends of the tank body 1. The other configuration is the same as that of the first embodiment, and the description thereof will be omitted by retaining the same reference numerals.

According to the structure of the second embodiment, the processing liquid raised to the upper part of the tank body 1 along the substrate 2 is supplied to the tank body 1
It is made to flow so as to collect on the overflow ports 22 on both sides of the upper part of the tank body 1 formed at both ends of the upper part of the tank body, and the processing liquid flows back from the upper part of the tank body 1 to the substrate 2 side. To prevent. In addition, by being dragged by the flows gathering at the overflow ports 22 on both sides of the upper portion of the tank body 1, the flow velocity above the substrate 2 is increased, the flow velocity difference above and below the substrate 2 is suppressed, and the flow velocity distribution is made uniform. ,
Reduce the processing time of the processing solution replacement.

FIG. 4 is a cross-sectional view showing a third embodiment of the substrate processing bath according to the present invention. The difference from the first embodiment is as follows.

In the closed position, the downward surface F1 of each of the covers 12 that comes into contact with the processing liquid is formed as an inclined surface that becomes lower toward the overflow tank 11, and the processing liquid that rises to the upper part of the tank body 1 is supplied to the overflow port. It is configured to easily flow to the 14 side. The other configuration is the same as that of the first embodiment, and the description thereof will be omitted by retaining the same reference numerals.

FIG. 5 is a cross-sectional view showing a fourth embodiment of the substrate processing tank according to the present invention. The difference from the first embodiment is as follows.

In the closed position, the downward faces of both covers 12 are configured to come into contact with the processing liquid and to be placed on the upper edge of the tank body 1. The other configuration is the same as that of the first embodiment, and the description thereof will be omitted by retaining the same reference numerals.

FIG. 6 is a cross-sectional view showing a fifth embodiment of the substrate processing bath according to the present invention, and FIG. 7 is a plan view of the fifth embodiment. The differences from the second embodiment are as follows. It is.

In the closed position, the downward surfaces of both covers 12 are configured to come into contact with the processing liquid and to be placed on the upper edge of the tank body 1. Further, outlets 31 are formed at predetermined pitches in the longitudinal direction of the tank main body 1 at locations close to the vertical wall surfaces on both sides of the tank main body 1 of each of the covers 12.
An overflow port is provided in which the position and area of the upper opening 13 are limited. The other configuration is the same as that of the first embodiment, and the description thereof will be omitted by retaining the same reference numerals.

FIG. 8 is a cross-sectional view showing a sixth embodiment of the substrate processing bath according to the present invention. The difference from the second embodiment is as follows. In the closed position, both covers 12
Each downward surface F2 is formed in an arc surface similar to the outer peripheral edge of the substrate 2 accommodated in the tank body 1. Further, the outlets 41 are formed at a predetermined pitch in the longitudinal direction of the tank body 1 so as to reach the downward surface F2 from a portion of the upper surface of each of the covers 12 close to the vertical wall on both sides of the tank body 1,
These multiple outlets 41 constitute an overflow port that restricts the position and area of the upper opening 13 of the tank body 1. Other configurations are the same as the first embodiment,
The description is omitted by attaching the same figure number.

According to the sixth embodiment, the processing liquid raised to the upper part of the tank body 1 is supplied to the outlet 41 by the downward surface F2.
And has the advantage of being able to discharge smoothly while suppressing the generation of eddy currents.

In the above-described embodiment, the pair of covers 12 is swung by the double-opening structure to be displaced between the closed position and the open position so that the space required for the displacement does not increase in the vertical direction. It may be composed of one cover. Instead of swinging, a combination of lifting and lowering and movement in the horizontal direction may be used to displace between the closed position and the open position.

In the above-described embodiment, the substrate 2 is stored in or taken out of the tank body 1 by the lifter 3. However, the present invention provides, for example, a cassette in which the substrate is stored is provided in the tank body. The immersion treatment may be performed by storing the immersion processing in the storage unit 1. Also, the present invention can be applied to a case where the substrates are immersed one by one.

In the above-described embodiment, the processing liquid is supplied from the processing liquid supply unit 9 toward the lower side of the center of the substrate 2 housed in the tank body 1 in a vertical posture.
The processing liquid may be supplied so as to be directed toward the center of the processing liquid.

[0038]

As is apparent from the above description, according to the first aspect of the present invention, the processing liquid supplied from the processing liquid supply section provided at the bottom of the tank main body is covered by the cover above the tank main body. The flow is made to collect on the overflow port side where the opening area is limited, and it is discharged while preventing it from flowing back from the upper part of the tank body to the substrate side. It is possible to prevent the processing solution in which gas is dissolved or bubbles or particles are taken in from acting on the substrate, thereby preventing the substrate from being contaminated, thereby improving the processing quality. In addition, since the flow velocity in the upper part of the tank body is increased to suppress the flow velocity difference between the top and bottom of the substrate and to make the flow velocity distribution uniform, different types of processing such as chemicals to pure water or pure water to chemicals are used. When replacing with a liquid, the replacement processing time can be shortened, the amount of the processing liquid used can be reduced, the economic efficiency can be improved, and the processing efficiency can be improved to increase the productivity. Moreover,
Since the cover is configured to be displaceable between a closed position where the lower surface contacts the processing liquid and an open position retracted from above the tank main body, the substrate can be taken in and out of the tank main body without being obstructed by the cover.

According to the second aspect of the present invention, the processing liquid raised to the upper portion of the tank main body along the substrate is placed above the center of the substrate housed in the tank main body at the upper portion of the tank main body. Pour so that it gathers on the overflow port side formed in the place,
Since the processing liquid is prevented from flowing from the upper part of the tank body back to the substrate side, the processing liquid containing particles removed from the substrate, dissolving gas at the liquid level, taking in bubbles and particles, To act on the substrate,
Contamination of the substrate can be avoided, and processing quality can be improved. Moreover, by increasing the flow velocity above the substrate,
Since the flow velocity difference between the top and bottom of the substrate is suppressed and the flow velocity distribution is made uniform, the processing time for processing liquid replacement can be shortened, the amount of processing liquid used can be reduced, and economy can be improved, and processing efficiency is improved and production is improved. Can be enhanced.

According to the third aspect of the present invention, the processing liquid raised to the upper part of the tank body along the substrate is applied to both sides of the upper part of the tank body formed on both ends of the upper part of the tank body. To prevent the processing liquid from flowing back from the upper part of the tank body to the substrate side, so that particles removed from the substrate may be mixed in or the gas may be dissolved at the liquid level. It is possible to prevent the processing liquid containing bubbles and particles from acting on the substrate, thereby preventing the substrate from being contaminated, thereby improving the processing quality. In addition, the flow velocity above the substrate is increased, the flow velocity difference above and below the substrate is suppressed, and the flow velocity distribution is made uniform, so that the processing time for processing liquid replacement can be shortened, and the amount of processing liquid used can be reduced, resulting in economy. The productivity can be improved as well as the processing efficiency can be improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a substrate processing tank according to the present invention.

FIG. 2 is a plan view of the first embodiment.

FIG. 3 is a cross-sectional view showing a second embodiment of the substrate processing tank according to the present invention.

FIG. 4 is a cross-sectional view showing a third embodiment of the substrate processing tank according to the present invention.

FIG. 5 is a cross-sectional view showing a fourth embodiment of the substrate processing tank according to the present invention.

FIG. 6 is a cross-sectional view showing a fifth embodiment of the substrate processing tank according to the present invention.

FIG. 7 is a plan view of a fifth embodiment.

FIG. 8 is a cross-sectional view showing a sixth embodiment of the substrate processing tank according to the present invention.

FIG. 9 is a cross-sectional view illustrating a conventional substrate processing bath.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Tank main body 2 ... Substrate 9 ... Processing liquid supply part 12 ... Cover 13 ... Upper opening 14 ... Overflow port 22 ... Overflow port 31 ... Outlet which comprises an overflow port 41 ... Outlet which comprises an overflow port

Claims (3)

[Claims] 1. A tank body for immersing a substrate stored in a vertical position with a processing liquid, and a processing liquid supply unit for supplying a processing liquid to the substrate stored in the tank body, In a substrate processing tank that processes a substrate by overflowing from an upper opening of the tank main body, the processing liquid supply unit is provided at a bottom of the tank main body, and the processing liquid is supplied upward along a plate surface of the substrate. A cover forming an overflow port having a limited area of the upper opening is provided with its lower surface in contact with the processing liquid, and the cover is closed at a position where the lower surface contacts the processing liquid. A substrate processing tank provided displaceably at an open position retracted from above the tank body. 2. The substrate processing tank according to claim 1, wherein the overflow port is provided while the cover is in the closed position.
A substrate processing tank formed on each of both upper ends of the tank body. 3. The substrate processing tank according to claim 1, wherein the overflow port is provided while the cover is in the closed position.
A substrate processing tank formed at an upper portion of the tank body and above a center of a substrate housed in the tank body.