JPH09246365A - Substrate holding jig - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a holding jig which is capable of surely fixing a photomask substrate in transit or processing without causing an adversary effect to the quality of a product. SOLUTION: A substrate holding jig is equipped with a base 110 which supports all the substrate holding jig itself, a side 120 provided continuously surrounding the base 110 around so as to protrude towards a substrate 200, and a close contact part 130 which comes into close contact with the substrate 200. The close contact part 130 is brought into contact with the substrate 200 to form a hermetically closed cavity 140 together with the substrate 200, and the cavity 140 is reduced in pressure through an exhaust pipe 160 through the intermediary of a connecting pipe 150 provided to the base of the cavity 140 to communicate with the cavity 140 to attract the one side of the substrate 200 and holds. The close contact part 130 is composed of an edge 131 which is formed like a continuous circle provided to the upper part of the side 120 protruding towards the substrate 200 to be flush with it and surrounding a region smaller than the substrate 200 and a plate-like, elastic, and flexible packing 135 which is provided and fixed along all the circumference of the edge 131 making its part protrude towards the substrate 200.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to LSI, VLSI, A
In the manufacturing process of high-density semiconductor integrated circuits such as SIC, the photomask manufacturing process used for manufacturing these high-density semiconductor integrated circuits, and the manufacturing process of flat panel displays such as LCD and PDP, the substrate is held and moved,
The present invention relates to a substrate holding jig used for fixing. In particular, the present invention relates to a substrate holder that can isolate a surface of a substrate that is not the processing surface side from a processing liquid or a processing gas even during processing.

[0002]

2. Description of the Related Art Conventionally, in the manufacture of high-density semiconductor integrated circuits such as LSI, VLSI, and ASIC, and in the manufacture of photomasks used for the same, the processed substrate is held and carried by a holding jig, or processed. In some cases, processing is performed, and as the holding jig, various types of substrate fixing methods have been used. For example, a method of sandwiching and fixing the board in a groove such as a rack, a method of sandwiching the side surface of the board,
A method of pressing the substrate from above and below, a method of sucking the substrate with a suction cup or the like can be mentioned. The holding jigs using these methods have their respective advantages, but they also have problems. In the case of, it is not possible to cope with complicated movements simply by placing the substrate on the groove. In the case of, there is no contact on the front and back of the board, and it is possible to handle complicated movements, but since the board is sandwiched from the side, the holding jig is larger than the board and must be small. I can't.
In the case of, there is no problem of increasing the size of the holding jig, but since it is pressed from the front and back surfaces of the substrate, it is necessary to contact the front and back surfaces of the substrate. Usually, contact of the holding jig with the surface of the substrate to be processed is disliked. In the case of,
There is no problem of, and if the suction cup is sucked on the back surface, the problem of will also disappear. However, since the suction cup has a circular shape or a shape close to it, a certain suction surface is required when the suction cup is sucked on the back surface of the substrate.

[0003]

However, it is said that the holding of the photomask substrate is not preferable in terms of quality even if it is sucked by the suction cup on the back surface that is not the processing side, and in the photomask fabrication, the conveyance of the photomask substrate is carried out. There has been a demand for a holding jig that can be fixed during uniform movement, particularly during process processing, without adversely affecting product quality. Under the circumstances, the present invention provides a holding jig that can securely fix the photomask substrate during movement such as transportation, especially during process processing without adversely affecting product quality. Is to provide.

[0004]

A holding jig of the present invention comprises a bottom portion for supporting the entire holding jig, a side surface portion continuously provided around the bottom portion and protruding toward the substrate, and a side surface portion of the side surface portion. A cavity portion provided on the substrate side and having a close contact portion for making close contact with the substrate, and in the state of being closely attached to the substrate at the close contact portion, a cavity portion sealed with the substrate is formed, and a cavity portion provided at the bottom portion. A holding jig for a substrate, which holds a substrate by adsorbing one side of the substrate by depressurizing the cavity by a gas exhaust unit via a connecting pipe connected to On the substrate side, a continuous circumference that surrounds a region smaller than the substrate size is formed, and the edge part that protrudes at the same height on the substrate side and the edge side of the edge part along the entire circumference of the edge part Is fixed to one surface forming a plate-shaped part of which is projected to the substrate side, It consists of a packing that has strength and flexibility, and when one side of the board is in contact with the packing, bend the packing to bring the board into close contact with the packing, form the cavity part, and exhaust the cavity part with the exhaust part. It is characterized in that the substrate is sucked and held in a reduced pressure state. Further, the edge portion in the above is formed by an edge having a surface whose center side is orthogonal to the bottom and a slope-shaped surface whose peripheral side is at an angle of 20 to 70 degrees with respect to the orthogonal plane, and It is characterized in that the packing is fixed to the surface. The entire circumference of the edge portion in the above corresponds to the entire outer circumference of the substrate to be processed, and is characterized in that it is provided with substantially the same size as the size of the substrate. Further, the substrate holding jig in the above is for holding the substrate under reduced pressure by the back surface which is not the processing surface of the substrate to be processed,
It is not corroded by the processing liquid or processing gas, and it withstands the mechanical force applied during processing sufficiently. During processing, the back surface of the substrate on the cavity side is processed liquid or processing. It is characterized in that it is isolated from the gas.

The material of each part of the holding jig is selected according to its purpose. For example, if you just want to hold the substrate,
Each part is not required to have chemical resistance, but when holding the substrate during processing, chemical resistance, mechanical strength, etc. suitable for the processing are required. Also, if the board itself is thin and the strength is weak, it is possible that the board will not be able to bend the packing when it comes into close contact with the packing, and it may be damaged. The property is also appropriately selected according to the strength of the substrate. The flexibility referred to here means that when the plate-like packing is in close contact with the substrate,
It is the property of bending at the bending edge.

[0006]

The holding jig of the present invention has such a structure that the fixing of the substrate such as the photomask substrate during the transportation or the like, especially the fixing during the process treatment, can be performed in the quality of the product. It is possible to provide a holding jig that can be reliably performed without adversely affecting it. Specifically, the contact portion for contact with the substrate has a side surface, on the substrate side, which forms a continuous circumference surrounding a region smaller than the substrate size, and an edge portion which protrudes at the same height on the substrate side. A plate-like, elastic, flexible packing that is fixed to one side of the edge part that forms the edge of the edge part along the entire circumference of the edge part and that protrudes partly toward the substrate side. When contacting one side of the board with the packing, the packing is bent to bring the board into close contact with the packing to form the cavity, and the exhaust section exhausts the cavity to reduce the pressure to adsorb the board. This is achieved by holding it. More specifically, when the cavity is evacuated by the evacuation unit to reduce the pressure, the substrate is pressed by the atmospheric pressure and adheres closely to the edge of the holding jig through the packing. As shown, since the packing has elasticity and flexibility, the packing comes to be crushed and bent by the edge portion 131 and the substrate 200, and serves as a seal for sealing the cavity 140. This allows
The holding of the substrate is solid. The edge of the edge portion is formed by a surface whose substrate center side is orthogonal to the bottom and a sloped surface whose substrate peripheral side is at an angle of 20 to 70 degrees with respect to the orthogonal surface, and which is a sloped surface. By fixing the packing to the, the seal is firmly fixed, and the edge portion can endure strength. The entire circumference of the edge part corresponds to the entire outer circumference of the substrate to be processed, and since it is provided with substantially the same size as the size of the substrate, it can be fixed only through the packing around the periphery of the substrate. If the front and back surfaces, including the back surface that is not the processing side such as a photomask, are sucked with a suction cup, it is possible to hold even a substrate having a quality problem without problems. Further, the substrate holding jig holds the substrate under reduced pressure by the back surface thereof, which is not the processing surface of the substrate to be processed, and is not corroded by the processing liquid or the processing gas, and at the time of processing. It sufficiently withstands the mechanical force applied. During processing, the back surface of the substrate on the cavity side is kept in a state of being isolated from the processing liquid or processing gas, so that the back surface of the substrate is not contaminated. ,
Eliminating quality problems.

[0007]

EXAMPLE An example of the substrate holding jig of the present invention will be described with reference to the drawings. 1A is a sectional view showing a schematic configuration of a holding jig of the embodiment, FIG. 1B is a sectional view showing a state in which a substrate is held, and FIG. 2A is a schematic perspective view of FIG. 2A, FIG. 2 is an enlarged cross-sectional view of a contact portion, which is a main portion, and FIG. 3 is a view showing an exhaust portion. 1, 2, and 3
Inside, 100 is a holding jig, 110 is a bottom portion, 120 is a side surface portion, 130 is a close contact portion, 131 is an edge portion, 132 is an edge, 133, 134 is a surface, 135 is a packing, 136 is a screw, 140 is a cavity portion, 150 is a connecting pipe, 160 is an exhaust part, 161 is a flexible tube, 162 is a vacuum gauge,
Reference numeral 163 is a leak valve, 164 is a vacuum line, and 200 is a substrate. This example relates to a jig for holding a photomask substrate when the glass substrate itself of the photomask substrate based on a quartz substrate having a plate thickness of 0.25 inches and a size of 6 inches is processed by wet etching. . As shown in FIG. 1, the holding jig 100 includes a bottom portion 110 that supports the whole and a substrate 2 that is continuous around the bottom portion 110.
It has a side surface portion 120 protruding to the 00 side and a contact portion 130 provided on the substrate 200 side of the side surface portion 120 for contacting with the substrate 200. Then, in the state where the substrate 20 is in close contact with the contact portion 130, the substrate 20
0 and the holding jig 100 form a closed cavity portion 140, and the exhaust portion 160 causes the cavity portion 140 to be depressurized through the connecting pipe 150 provided in the bottom portion 110. One side is held under reduced pressure to adsorb the substrate 200.

The contact portion 130 is formed on the side surface 120 of the substrate 20.
On the 0 side, a continuous circumference is formed that surrounds a region substantially the same as the substrate size, and the edge portion 131 protruding toward the substrate 200 side at the same height, the edge portion 131 on the substrate 200 side, and the entire circumference of the edge portion 131. Along the surface of the edge portion 131 forming the edge 132, a plate-like packing 1 having a part thereof protruding toward the substrate 200 and having elasticity and flexibility is provided.
35. The distance between the opposing edges is approximately 3 mm longer than the size of the corresponding substrate. As shown in FIG. 2, the edge portion 131 includes an edge 132, which is a slope-shaped surface having an angle of 60 degrees with respect to a surface 133 of the substrate center side orthogonal to the bottom 110 and a surface of the substrate peripheral side orthogonal to the orthogonal surface 133. Surface 1 formed by 134 and having a slope shape
The packing 135 is fixed to 34 by screws 136. Then, a cavity 140 is formed so that one side of the substrate 200 is in contact with the packing 135, and the cavity 140 is evacuated by the exhaust unit 160 to a depressurized state, and the substrate 200 is adsorbed as shown in FIG. Hold. It should be noted that the substrate 200 and the holding jig 100 are aligned so that the edge 132 hits at a position 1 to 2 mm inside the outermost periphery of the substrate, and the substrate 100 is held at this position via the packing 135. .

The exhaust unit 160 exhausts air through the connecting pipe 150. As shown in FIG.
The flexible tube 161 is connected to the vacuum line 164, and the flexible tube 161 is connected to the vacuum line 164. Vacuum line 164 and connecting pipe 150
A leak valve 163 and a vacuum gauge 162 are provided between and, so that the degree of pressure reduction can be adjusted.

As described above, this embodiment is a jig for holding the photomask substrate when the glass substrate itself of the photomask is processed by wet etching. More specifically, a predetermined portion is formed by a resist or a metal film. This is a holding jig for wet etching only the exposed quartz glass portion of the surface of the protected substrate. For etching the quartz glass itself, a solution of hydrofluoric acid, buffered hydrofluoric acid or the like, an alkaline solution of sodium hydroxide, potassium hydroxide or the like, and an acidic solution of phosphoric acid or the like are used. The material of each part was determined so as to withstand the use of the etching solution of. Although Teflon is used for the bottom portion 110, the side surface portion 120, the edge portion 131, the screw 136, and the connecting pipe 150, a metal or alloy having high chemical resistance such as titanium may be used. The packing 135 is made of DuPont Kalrez, which is rubber, has elasticity, has high chemical resistance, and is flexible.
It is not particularly limited to this. Another particularly preferable material is Chemraz, manufactured by Green Tweed.

Next, the operation of holding the photomask substrate by the holding jig of this embodiment will be specifically described with reference to FIG. First, after aligning the substrate 200 and the holding jig 100, the substrate 200 is placed on the contact portion 130 of the holding jig 100. (FIG. 4A) Next, when the exhaust part 160 exhausts the cavity 140, the substrate 200 is pressed by the atmospheric pressure, and the packing 13
As 5 is crushed, it functions as a seal and the substrate 200 is fixed to the holding jig. (FIG. 4B) The degree of vacuum reduced by the exhaust unit 160 adjusts the leak valve 163 to control the force applied to the substrate 200. It is determined in consideration of the thickness and strength of the substrate 200. Next, the held and fixed substrate 200 is placed on the lower side and is immersed in a wet etchant together with the holding jig 100. (FIG. 4 (c)) After the etching process is completed, the holding jig 100 and the substrate are pulled up from the etching solution and subjected to a process such as cleaning.
As shown in (b), with the substrate 200 facing upward, the leak valve 163 shown in FIG. 3 is fully opened to bring the cavity to atmospheric pressure, and the substrate 200 is removed from the holding jig 100. By doing so, in the wet etching process in the production of the photomask, the substrate, the back side of the non-processed side can be easily held in close contact with only the outermost periphery of the back surface of the substrate without touching the etching solution. It is possible to deal with both quality and work.

[0012]

As described above, the substrate holding jig of the present invention is a holding jig that can supplement the drawbacks found in the conventional holding jigs. It is assumed that they can be easily held in close contact. As a result, not only can the substrate be held without problems in terms of quality and work, but also the overall size of the holding jig can be made equal to or smaller than the size of the substrate.

[Brief description of drawings]

FIG. 1 is a schematic view of a substrate holding jig according to an embodiment.

FIG. 2 is an enlarged cross-sectional view of a contact portion, which is a main portion of the substrate holding jig of the embodiment.

FIG. 3 is a simplified diagram for explaining an exhaust portion of the substrate holding jig of the embodiment.

FIG. 4 is a process drawing of a wet etching process using the holding jig of the embodiment.

[Explanation of symbols]

 100 Holding jig 110 Bottom part 120 Side part 130 Adhesive part 131 Edge part 132 Edge 133, 134 Surface 135 Packing 136 Screw 140 Cavity part 150 Connecting pipe 160 Exhaust part 161 Flexible tube 162 Vacuum gauge 163 Leak valve 200 Substrate 300 Etching liquid 310 Etching Tank

Claims (4)

[Claims] 1. A bottom portion that supports the entire holding jig, a side surface portion that continuously extends around the bottom portion and protrudes toward the substrate side, and a side surface portion that is provided on the substrate side and that is in close contact with the substrate. With a close contact portion, and in a state of being in close contact with the substrate at the close contact portion, a hollow portion that is sealed with the substrate is formed, and through the connecting pipe that is connected to the hollow portion provided at the bottom portion, by the exhaust portion, ,
A holding jig for a substrate, which holds a substrate by adsorbing one side of the substrate by depressurizing the hollow portion, wherein the contact portion is a continuous side portion surrounding a region smaller than the substrate size on the substrate side. An edge part that forms a perimeter and protrudes at the same height on the substrate side, and is fixed to one side forming the edge of the edge part along the entire periphery of the edge part, on the substrate side of the edge part, and part of it It consists of a plate-shaped elastic and flexible packing that protrudes to the board side.When one side of the board is in contact with the packing, the packing is bent to adhere the board to the packing and form the cavity. Then, the holding jig for a substrate is characterized in that the cavity is evacuated by the evacuation unit to bring it into a decompressed state to adsorb and hold the substrate. 2. The edge portion according to claim 1, wherein the edge is formed by a surface having a substrate center side orthogonal to a bottom portion and a slope-shaped surface having a substrate peripheral portion side with an angle of 20 to 70 degrees with respect to the orthogonal surface. In addition, the substrate holding jig is characterized in that the packing is fixed to the slope-shaped surface. 3. The holding jig for a substrate according to claim 2, wherein the entire circumference of the edge portion corresponds to the entire outer circumference of the substrate to be processed. 4. The substrate holding jig according to any one of claims 1 to 3, which holds the substrate under reduced pressure by the back surface of the substrate to be processed, which is not the processing surface, and corrodes the processing liquid or the processing gas. In addition, the back surface of the substrate on the side of the cavity should be isolated from the processing liquid or the processing gas during processing, since it does not withstand the mechanical force applied during processing. A holding jig for substrates, characterized by: