JP2020019667A - Etching apparatus - Google Patents

Abstract

To provide an etching apparatus for etching a to-be-processed substrate such as a glass substrate while conveying the substrate, the etching apparatus being capable of preventing contamination of the interior of processing chambers and improving the maintainability.SOLUTION: An etching apparatus 10 is configured to spray etching liquid on a glass substrate 24 being conveyed in a predetermined direction, comprising conveyor rollers 30, a spray unit 32, and a plurality of etching chambers 161, 162. The etching chambers 161, 162 are configured to accommodate at least the conveyor rollers 30 and the spray unit 32 therein, and have a transparent ceiling part 40 arc-shaped in cross-sectional view. The ceiling part 40 includes door bodies 50. The door bodies 50 are rotatably supported on opening portions 52.SELECTED DRAWING: Figure 4

Description

  The present invention relates to an apparatus for etching a substrate to be processed, such as a glass substrate, and more particularly to a single wafer type etching apparatus that sprays an etching solution onto a substrate to be processed.

  In recent years, flat panel displays such as liquid crystal displays have been increasingly required to be thinner. In a flat panel display panel manufacturing process, a flat panel display panel is manufactured by sealing a functional layer necessary for image display such as a liquid crystal layer with two glass substrates. In order to provide a thin display, it is effective to make the glass substrate thin by an etching process.

  As the etching process, a wet etching process for bringing a glass substrate into contact with an etchant is generally employed. The wet etching treatment is roughly classified into single-wafer etching and immersion etching. Single-wafer etching is a method in which an etching solution is sprayed onto a glass substrate being transported by using a spray or the like. The immersion etching is performed by immersing a jig holding a plurality of glass substrates in an etching bath containing an etching solution. In particular, single-wafer etching is considered to be more advantageous for thinning glass substrates than immersion etching, and in recent years, demand for single-wafer etching has been increasing.

  Further, in the single-wafer etching apparatus, since a substrate to be processed is processed in a processing chamber, there is little possibility that an etchant is scattered outside the apparatus or an acidic gas such as hydrofluoric acid leaks out of the apparatus (for example, , Patent Document 1). For this reason, the single-wafer etching apparatus is considered to be excellent also in terms of worker safety and working environment.

JP 2005-015913 A

  As the etchant reacts with the glass substrate, sludge, which is an insoluble product, is generated in the etchant. In the single-wafer etching apparatus, the etching liquid adheres to the inner wall of the processing chamber and dries, so that sludge may adhere to the processing chamber and clog pipes and exhaust ports. In order to remove the sludge, maintenance in the processing chamber is required. However, an etching solution is attached to the inner wall of the processing chamber, and the worker performing the maintenance requires protective equipment such as protective clothing. For this reason, maintenance work has been complicated.

  In addition, there is a case where the etching solution attached to the ceiling drops due to the influence of gravity and is attached to the substrate to be processed. In this case, sludge in the etchant may adhere to the surface of the glass substrate, resulting in uneven etching. Such etching unevenness is more likely to become a problem in quality as the thickness of the glass substrate becomes thinner.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a single-wafer etching apparatus capable of preventing contamination in a processing chamber and improving maintainability.

  An etching apparatus according to the present invention is an etching apparatus configured to spray an etching solution onto a substrate to be processed that is being transported in a predetermined direction, and includes a transport path, a spray unit, and a processing chamber.

  The transfer path is configured to transfer the substrate to be processed in a predetermined transfer direction. The spray unit is configured to spray an etchant on the substrate to be processed on the transport path. The processing chamber is configured to house at least the transfer path and the spray unit therein. The processing chamber has a ceiling and a door formed on the ceiling. The ceiling is arcuate in cross section and has transparency. Here, the arc shape in a sectional view means that the shape of the cross section orthogonal to the transport direction has an arc shape.

  According to the present invention, the etching solution scattered in the processing chamber slides down the ceiling in an arc shape in cross section, so that the etching solution adheres to the processing chamber and adheres as sludge, or the etching solution adheres to the inner wall. It is possible to prevent a problem such as dropping on a processing substrate. Further, by disposing the door on the ceiling, maintenance such as replacement of parts of the spray unit can be performed with the door being opened.

  Further, it is preferable that the door has a shape along the ceiling and is rotatably supported. Since the door has the same curved shape as the ceiling, it is possible to prevent the etching liquid or the like from remaining in the door. In addition, by rotatably supporting the door, it is not necessary to remove the door from the etching apparatus when the door is opened and closed.

  Further, it is preferable that the ceiling and the door are formed of a transparent resin, and that a polymethylpentene film is adhered to an inner wall of the transparent resin material. The use of the transparent resin facilitates the formation of a curved shape. In addition, by making the ceiling part circular in cross section, the load applied to the ceiling part can be dispersed, so that the mechanical strength of the etching apparatus can be maintained even with a resin material. In addition, by reducing the structure of the ceiling portion such as a reinforcing material, it is possible to suppress accumulation of the etching liquid in the ceiling portion. Polymethylpentene film is a low surface tension resin having chemical resistance and transparency. For this reason, the etching liquid easily flows down along the ceiling, and the adhesion of sludge in the etching chamber can be suppressed.

  Further, it is preferable that the spray unit slides in a direction orthogonal to the direction of transport of the substrate to be processed. By sliding the spray unit, the etching liquid can be uniformly sprayed onto the substrate to be processed, and the possibility of uneven etching can be reduced. Furthermore, since the ceiling has an arc shape in cross section, it is possible to secure a movable area of the spray unit.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the single-wafer etching apparatus which can prevent the contamination in a processing chamber, and can aim at the improvement of maintainability.

It is a schematic diagram of an etching device concerning one embodiment of the present invention. 1 is a schematic side view of an etching apparatus according to an embodiment of the present invention. FIG. 2 is a diagram illustrating a configuration of an etching chamber according to an embodiment of the present invention. It is a figure showing the state where the door was opened.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. 1A and 1B are schematic diagrams of a glass substrate etching apparatus 10 according to the present embodiment. The etching apparatus 10 includes a carry-in unit 12, a pre-washing chamber 14, a first etching chamber 161, a second etching chamber 162, a post-washing chamber 18, an unloading unit 20, and a transport roller 30.

  The transport roller 30 is arranged along the length direction of the etching device 10 as shown in FIG. 2 and is configured to transport the glass substrate 24 in the horizontal direction. The transport rollers 30 are arranged at regular intervals in the transport direction of the glass substrate 24, and are configured to transport the glass substrate 24 by supporting it from below. The transport roller 30 corresponds to a transport path described in the claims. The transport speed of the glass substrate 24 is preferably set as appropriate in consideration of the size and thickness of the glass substrate 24, the jet pressure of the etching solution, the composition of the etching solution, and the like. The etching apparatus 10 is configured to perform an etching process such as thinning by spraying an etchant on the glass substrate 24 being transported by the transport roller 30.

  The loading unit 12 is configured to introduce the glass substrate 24 into the etching apparatus 10 by placing the glass substrate 24 on the transport roller 30. The glass substrate 24 is etched by passing through each chamber while being transported in the horizontal direction by the transport roller 30, and is etched until a desired thickness is obtained. The glass substrates 24 are sequentially put into the etching apparatus 10 at predetermined intervals.

  The pre-washing chamber 14 is disposed downstream of the loading unit 12. The pre-washing chamber 14 is configured to spray cleaning liquid onto the glass substrate 24 being transported by the transport roller 30 from spray units 32 disposed above and below the transport roller 30. If the etchant is brought into contact with the dried glass substrate, the glass substrate may become cloudy. For this reason, the etching apparatus 10 is configured to spray the cleaning liquid at a stage preceding the etching chamber. In the present embodiment, city water is used as the cleaning liquid.

  The first etching chamber 161 and the second etching chamber 162 have substantially the same configuration, and are configured to spray an etching solution onto the glass substrate 24 being transported. In each of the etching chambers 161 and 162, a spray unit 32 is disposed above and below the transport roller 30, and the spray liquid is sprayed from the spray unit 32 onto the glass substrate 24 on the transport roller 30.

  The spray unit 32 has a plurality of spray nozzles 36 arranged in a liquid feed pipe 34, and is configured such that the etchant is sprayed uniformly on the glass substrate 24. The etchant is configured to be supplied from a tank or the like that contains the etchant whose composition has been adjusted. The reciprocating movement of the spray unit 32 makes it possible to spray the etchant more uniformly on the glass substrate 24 and prevent the etchant from remaining on the upper surface of the glass substrate 24. Note that the arrangement of the spray units 32 and the number of the injection nozzles 36 can be appropriately changed according to the size of the substrate to be processed and the etching amount.

  As shown in FIG. 3, the etchant sprayed in each etching chamber is discharged from a discharge port 38 disposed at a lower part of the etching chamber. The etching liquid discharged from the discharge port 38 is collected in a tank (not shown), and is supplied from the tank to the spray unit 32 again.

  The etchant in the present embodiment contains at least hydrofluoric acid, and may contain an inorganic acid such as hydrochloric acid or sulfuric acid, or a surfactant. The composition and temperature of the etching solution can be appropriately changed depending on the amount of etching and the type of the substrate to be processed. Although the etching apparatus 10 has two etching chambers, the number of etching chambers can be changed in consideration of a substrate to be processed, an installation place, and the like.

  As shown in FIGS. 1B and 3, each of the etching chambers 161 and 162 is covered by a ceiling 40 having an arc shape in cross section. The ceiling 40 includes a transparent member 42, a frame body 44, and a protective film 46. The transparent member 42 is made of a resin member that is resistant to an etchant, and has an arc shape in cross section. Examples of the resin member used as the transparent member 42 include a polyethylene resin, a fluorine resin, and a polypropylene resin. The transparent member 42 can be processed into a desired curved shape by thermal processing.

  The frame body 44 is attached to the outer wall side of the transparent member 42 in order to maintain the strength of the processing chamber. The frame body 44 is made of a metal member such as iron, and is arranged in a lattice. Since the frame body 44 is attached to the outer wall side of the transparent member 42, there is no need to arrange an extra structure on the inner wall side of the transparent member 42. This eliminates the problem that the scattered etchant accumulates in the uneven portion on the inner wall side, and allows the etchant to be discharged along the wall surface of the ceiling 40. Further, since the ceiling 40 has a small number of structures, visibility in the etching chamber can be improved.

  The protective film 46 is a transparent film attached to the inner side of the transparent member 42. As the protective film 46, a polymethylpentene film can be used. Since the polymethylpentene film is a transparent film and has chemical resistance, it does not deteriorate even if it is attached to the inner wall of the etching chamber. In addition, since polymethylpentene has a low surface tension, the etchant scattered on the inner wall easily flows along the wall surface.

  When a polymethylpentene film is used, the polymethylpentene resin is stretched, cut into a predetermined size suitable for a component to be applied, and then subjected to a surface modification treatment by a corona surface treatment machine. The surface modification treatment can be performed using a known corona discharge treatment device such as a vacuum tube method or a thyristor method. In this embodiment, a distance of about 0.1 to 10 mm is provided between the discharge electrode and the polymethylpentene film, and the processing is performed by applying an applied voltage of 0.1 to 50 kV. The surface of the polymethylpentene film on which the surface modification treatment has been performed is a surface to be adhered to another transparent resin, and an adhesive layer is formed on the surface to be adhered.

  The transparent member 42 is provided with a door 50 that can be opened and closed (see FIG. 1B). The door body 50 selectively opens or closes an opening 52 formed in the ceiling 40. At the time of closing, the door body 50 is fitted into the opening 52, and the etching chamber is sealed. A sealing material 60 is disposed on the periphery of the opening 52 to improve the hermeticity of the etching chamber.

  The door body 50 is formed of the transparent member 42 similarly to the ceiling 40, and has a curved shape. Further, a protective film 46 is also attached to the inner surface side of the door body 50. Thus, the possibility that the etching solution stays in the door body 50 is reduced, and the etching solution drops along the ceiling 40.

  The door body 50 is rotatably supported at the end of the opening 52 by a hinge 54. Note that the hinge part 54 is also formed of the transparent member 42. As shown in FIG. 4A, the door body 50 can be opened by rotating upward. The door body 50 is provided with a grip portion 56, and the worker lifts the grip portion 56 so that the door body 50 rotates around the hinge portion 54. Note that the door body 50 is preferably fixed by a fixing mechanism that can be fixed in a state of being opened upward.

  Two adjacent processing chambers such as the pre-washing chamber 14 and the first etching chamber 161 are separated by a partition as shown in FIG. The housing of the etching chamber including the partition walls (excluding the ceiling portion 40) is formed of a resin having a resistance to hydrofluoric acid such as polyvinyl chloride. The partition wall is formed with a slit portion 28 that connects the two processing chambers so that the glass substrate 24 can pass therethrough. The slit portion 28 is formed at a height that allows the glass substrate 24 to pass through, and is preferably formed at a height of 4 to 10 mm.

  The post-washing chamber 18 is disposed downstream of the second etching chamber 162. The post-washing chamber 18 is configured to wash away the etchant by injecting a cleaning solution from above and below the glass substrate 24 as in the pre-washing chamber 14. As the cleaning liquid, city water is used similarly to the pre-washing chamber 14.

  An air knife 26 is arranged at the most downstream portion of the post-cleaning chamber 18. The air knife 26 is configured to eject air to the glass substrate 24 to remove the cleaning liquid attached to the surface. The glass substrate 24 that has been dried by the air knife 26 is collected at the unloading section 20.

  The glass substrate 24 is subjected to an etching process by sequentially passing through the pre-washing chamber 14, the first etching chamber 161, the second etching chamber 162, and the post-washing chamber 18. By putting the glass substrate 24 into the etching apparatus 10 once or a plurality of times, the thickness can be reduced to, for example, about 0.05 to 0.3 mm. At this time, since the ceiling portion 40 of each chamber is formed of the transparent member 42, it is easy to check the state of the glass substrate 24 during the etching process, and it is checked whether or not a problem occurs during the thinning process. Is easy.

  Further, by forming the ceiling portion 40 into an arc shape in a sectional view, the load applied to the ceiling portion 40 can be dispersed, so that the ceiling portion 40 is formed using the transparent resin material 42 with almost no reinforcing member. can do. By using the transparent resin 42, the contamination of the wall surface of the etching chamber due to the scattering of the etching solution can be suppressed while improving the visibility in the etching chamber.

  Further, by providing the door body 50 and the opening 52, maintenance in the etching chamber such as the spray unit 32 becomes easy. Since the ceiling 40 has an arc shape in cross section, the distance between the opening 52 and the spray unit 32 is relatively short, so that the burden on the operator during maintenance work can be reduced.

  Further, due to the curved shape of the door body 50, even when the door body 50 is opened, the etching liquid attached to the inner wall side of the door body 50 does not adhere to the periphery of the etching device 10. Further, as shown in FIG. 4B, since the etching liquid flows along the curved shape of the door 50, the etching liquid finally falls through the opening 52 into the etching chamber. Thereby, the contamination of the peripheral portion of the etching apparatus 10 can be prevented.

  Although the present embodiment has been described by taking a glass substrate as an example, the etching apparatus according to the present invention is not limited to etching a glass substrate. For example, a laminated substrate in which a semiconductor substrate or a glass substrate and a resin substrate are laminated can be processed. In the case of processing these substrates, an etching solution corresponding to the substrate to be processed may be prepared.

  The description of the above embodiment is illustrative in all aspects and should not be construed as limiting. The scope of the present invention is defined by the terms of the claims, rather than the embodiments described above. Further, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the claims.

DESCRIPTION OF SYMBOLS 10-Etching apparatus 12-Incoming part 14-Front rinsing chamber 161-First etching chamber 18-Rinse rinsing chamber 20-Unloading part 24-Glass substrate 30-Transport roller 32-Spray unit 34-Liquid supply pipe 36-Injection nozzle 38-outlet 40-ceiling 42-transparent member 44-frame 46-protective film 50-door 52-opening

Claims (4)

An etching apparatus configured to inject an etching solution to a substrate to be processed being transported in a predetermined direction,
A transfer path configured to transfer the substrate to be processed in a predetermined transfer direction,
A spray unit that sprays an etching solution on the substrate to be processed on the transport path,
A processing chamber configured to house the transport path and the spray unit at least therein,
At least,
The processing chamber has an arc shape in cross section, and a ceiling having transparency,
A door provided on the ceiling,
An etching apparatus comprising:   2. The etching apparatus according to claim 1, wherein the door has a shape along the ceiling, and is rotatably supported by the ceiling. 3.   3. The etching apparatus according to claim 1, wherein the ceiling and the door are formed of a transparent resin, and a polymethylpentene film is attached to an inner wall of the transparent resin material. 4.   4. The etching apparatus according to claim 1, wherein the spray unit slides in a direction perpendicular to a direction in which the substrate to be processed is transported. 5.

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