Circuit Board Cassette

Abstract

To provide a substrate cassette which can reduce failure in drying substrates during a wet process.SOLUTION: A substrate cassette 1 is used to simultaneously soak a plurality of substrates W into liquid after arranging the plurality of substrates W such that their principal surfaces face each other. The substrate cassette comprises: a plurality of lateral support columns 30 which extends in an arrangement direction of the plurality of substrates W so as to supports lateral ends of the plurality of substrates W; a plurality of claw parts 32 which is disposed in the arrangement direction on the lateral parts of the lateral support columns 30 and protrudes from the lateral parts of the lateral support columns 30, thereby supporting the plurality of substrates W such that they are spaced apart from each other; and a draining protrusion 34 which is disposed on a lower portion of each of the lateral support columns 30 and extends in the arrangement direction, and whose cross-sectional shape intersecting the arrangement direction has an inverted triangle shape protruding downward. A surface of the draining protrusion 34 has a hydrophobic property, while the lateral parts and upper portions of the lateral support columns 30 have a hydrophilic property.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a substrate cassette. [Background technology]

[0002] For example, wet processes are used in the manufacturing process of solar cells, including patterning of thin films such as semiconductor layers or electrode layers formed on semiconductor substrates (wafers), peeling of resists or lift-off layers (sacrificial layers) used in such patterning, and cleaning of the surface of the semiconductor substrate.

[0003] In such wet processes, a substrate cassette is used to simultaneously immerse a plurality of semiconductor substrates in a liquid such as a chemical solution (e.g., an etching solution) or water (e.g., a rinsing solution). Patent documents 1 and 2 describe substrate processing apparatuses as such substrate cassettes.

[0004] Such a substrate cassette accommodates a plurality of semiconductor substrates arranged with their main surfaces facing each other, and in a wet process, the substrate cassette is immersed in a liquid so that the plurality of semiconductor substrates are perpendicular to the liquid surface, and then the substrate cassette is removed from the liquid. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Utility Model Application Publication No. 5-90943 [Patent Document 2] Patent No. 4974996 Summary of the Invention [Problem to be solved by the invention]

[0006] In a wet process, for example, after the substrate cassette is removed from the pure water (rinsing solution) (after the rinsing step), the multiple semiconductor substrates are dried while still contained in the substrate cassette. For example, water droplets on the surfaces of the multiple semiconductor substrates are removed by blowing dry air onto the multiple semiconductor substrates from the side of the substrate cassette.

[0007] At this time, if water droplets are attached to the side supports of the substrate cassette, the water droplets will be scattered by the drying wind and remain on the surface of the semiconductor substrate. The remaining water droplets during drying cause poor drying, resulting in the formation of so-called water marks (drying stains) on the surface of the semiconductor substrate. For example, water marks (drying stains) become dark spots on the solar cell, which can lead to a decrease in the performance and yield of the solar cell.

[0008] In this regard, the substrate processing apparatus (substrate cassette) described in Patent Document 1 comprises a holding mechanism (corresponding to the side supports in the present application) that holds multiple semiconductor substrates aligned at regular intervals, and a liquid-cutting member (corresponding to the water-cutting protrusion in the present application) that is suspended from the holding mechanism and formed with a sharp point facing downward, and that promotes the dripping of processing liquid adhering to the holding mechanism.

[0009] Furthermore, the substrate processing apparatus (substrate cassette) described in Patent Document 2 comprises a lower holder (corresponding to the lower support in the present application) that supports the lower end of the substrate to be processed, and an upper holder (corresponding to the lateral support in the present application) that holds the lower side end of the substrate to be processed, the lower holder being formed from a hydrophilic material, and the upper holder being formed from a hydrophobic material.

[0010] However, in the substrate processing apparatus (substrate cassette) described in Patent Document 1, a liquid-cutting member (corresponding to the water-cutting protrusion in the present application) that promotes dripping of processing liquid is formed at the bottom of the holding mechanism (corresponding to the side support in the present application), but no consideration is given to water droplets that adhere to the top and sides of the holding mechanism.

[0011] In addition, in the substrate processing apparatus (substrate cassette) described in Patent Document 2, the upper holder (corresponding to the side supports in the present application) is made of a hydrophobic material, but no consideration is given to water droplets adhering to the top and sides of the upper holder. Hydrophobic materials repel water, so water droplets end up forming on the top and sides.

[0012] Thus, even the techniques described in Patent Documents 1 and 2 do not sufficiently reduce water droplets adhering to the side supports of the substrate cassette, and therefore do not sufficiently reduce water marks (drying stains) on the surface of the substrate caused by water droplets adhering to the side supports, which are left on the substrate during drying, i.e., poor drying of the substrate.

[0013] An object of the present invention is to provide a substrate cassette that reduces insufficient drying of substrates in a wet process. [Means for solving the problem]

[0014] The substrate cassette according to the present invention is a substrate cassette for arranging a plurality of substrates with their main surfaces facing each other and immersing the plurality of substrates simultaneously in a liquid, the substrate cassette comprising: a plurality of side supports extending in an arrangement direction of the plurality of substrates and supporting side edges of each of the plurality of substrates; a plurality of claws arranged on sides of the side supports in the arrangement direction and protruding from the sides of the side supports for supporting each of the plurality of substrates so that the plurality of substrates are spaced apart; and a drainage protrusion arranged on a lower portion of the side supports, extending in the arrangement direction and having a cross-sectional shape intersecting the arrangement direction that is an inverted triangle protruding downward. The surface of the drainage protrusion is hydrophobic, and the sides and upper portions of the side supports are hydrophilic. Effect of the Invention

[0015] According to the present invention, insufficient drying of substrates can be reduced in a wet process using a substrate cassette. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is a perspective view showing a substrate cassette according to the embodiment; [Diagram 2] FIG. 2 is a side view of the substrate cassette shown in FIG. [Diagram 3] 3 is a cross-sectional view of the substrate cassette shown in FIG. 2 taken along line III-III. [Figure 4] 3 is an enlarged view of a fin portion (water drainage projection) in the substrate cassette shown in FIG. 2. [Diagram 5] 5 is a diagram showing the flow of drying air and treatment liquid in the vicinity of the fin portion (water-draining projection) shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals. For convenience, hatching and reference numerals may be omitted, in which case other drawings shall be referred to.

[0018] Fig. 1 is a perspective view showing a substrate cassette according to the present embodiment, Fig. 2 is a side view of the substrate cassette shown in Fig. 1, and Fig. 3 is a cross-sectional view of the substrate cassette shown in Fig. 2 taken along line III-III.

[0019] 1 to 3 is used in wet processes in the manufacturing process of solar cells, for example. Such wet processes include patterning of thin films such as a semiconductor layer (e.g., an amorphous silicon-based thin film) or an electrode layer formed on a semiconductor substrate (wafer: thin plate) (e.g., a crystalline silicon-based substrate) W, peeling off a resist or lift-off layer (sacrificial layer) used in such patterning, and cleaning of the surface of the semiconductor substrate W.

[0020] In a wet process, the substrate cassette 1 simultaneously immerses a plurality of semiconductor substrates W in a liquid such as a chemical solution (e.g., an etching solution) or water (e.g., a rinsing solution). The substrate cassette 1 accommodates a plurality of semiconductor substrates W arranged with their main surfaces facing each other. In a wet process, the substrate cassette 1 is immersed in a liquid so that the plurality of semiconductor substrates W are perpendicular to the liquid surface, and the substrate cassette 1 is then removed from the liquid. Then, for example, after a rinsing process, the plurality of semiconductor substrates W are dried while still accommodated in the substrate cassette 1. For example, water droplets on the surfaces of the plurality of semiconductor substrates W are removed by blowing dry air onto the plurality of semiconductor substrates W from the side of the substrate cassette 1.

[0021] The substrate cassette 1 comprises a front panel 11, a rear panel 12, a lower support pillar 21, an upper support pillar (not shown), a side support pillar 30, a claw portion 32, and a fin portion (water drainage protrusion) 34.

[0022] As the material of each component of the substrate cassette 1, various materials having resistance to liquid are used. For example, when the liquid is an acidic solution, the material of each component of the substrate cassette 1 may be a resin material such as PTFE (Poly Tetra Fluoro Etylene), PVDF (Poly Vinylidene DiFluoride), or PP (polypropylene). In order to suppress mechanical damage to the substrate, a metal material such as SUS (Steel Use Stainless) or a titanium alloy may be used as the mandrel, and the outer periphery may be covered with a resin material. When the liquid is an alkaline solution, the material of each component of the substrate cassette 1 may be a metal material such as SUS or a titanium alloy, or a resin material such as PTFE, PVDF, or PP. As described above, in order to increase the mechanical strength, a metal material such as SUS or a titanium alloy may be used as the mandrel, and the outer periphery may be covered with a resin material.

[0023] The front plate 11 is disposed on the front side of the substrate cassette 1, and the rear plate 12 is disposed on the rear side of the substrate cassette 1. The front plate 11 and the rear plate 12 face each other so as to sandwich a plurality of semiconductor substrates W therebetween.

[0024] The lower support 21 is disposed at the bottom of the substrate cassette 1, and supports the bottom ends of the multiple semiconductor substrates W. There are no particular limitations on the type of lower support 21, and examples of such support include columnar members extending from the front plate 11 to the rear plate 12, i.e., in the arrangement direction of the semiconductor substrates W, in consideration of not impeding liquid convection and of draining liquid, etc.

[0025] The upper support (not shown) is disposed on the upper portion of the substrate cassette 1, and supports the upper ends of the multiple semiconductor substrates W, for example, when the substrate cassette 1 is immersed in liquid. The upper support is not particularly limited, and may be, for example, a columnar member extending from the front plate 11 to the rear plate 12, i.e., in the arrangement direction of the semiconductor substrates W, in consideration of not impeding the convection of the liquid. The upper support may be detachable or openable in order to set and reset the multiple semiconductor substrates W in the substrate cassette 1.

[0026] The side supports 30 are disposed on the sides of the substrate cassette 1 and support the side ends of the semiconductor substrates W. The side supports 30 are not particularly limited, and may be columnar members extending from the front plate 11 to the rear plate 12, i.e., in the arrangement direction of the semiconductor substrates W, in consideration of not impeding the convection of the liquid, not impeding the drainage of the liquid, and not impeding the drying wind. The number of the side supports 30 is not particularly limited, and for example, two side supports 30 may be disposed vertically spaced apart on each of the two pairs of sides. The side supports 30 include a plurality of claws 32 and a fin portion (water drainage protrusion) 34.

[0027] The multiple claws 32 are arranged at equal intervals on the inner side of the side column 30 in the extension direction of the side column 30 (arrangement direction of the semiconductor substrates W). As a result, the multiple claws 32 support each of the multiple semiconductor substrates W so that the multiple semiconductor substrates W are spaced apart. There are no particular limitations on the type of claw 32, and it is preferable that the claws protrude from the inner side of the side column 30 and have a small contact area with the semiconductor substrate W, for example.

[0028] The fin portion (water drainage protrusion) 34 is disposed on the lower portion of the side support 30, and extends in the extension direction of the side support 30 (arrangement direction of the semiconductor substrate W). The cross-sectional shape of the fin portion 34 intersecting with the extension direction of the side support 30 is an acute-angled inverted triangle shape that protrudes downward.

[0029] As a result, when the substrate cassette 1 is removed from the liquid, or more specifically, when the fin portion (water-draining protrusion) 34 is removed from the surface of the liquid, the contact changes from surface to point contact, thereby reducing the adhesion of water droplets due to surface tension.

[0030] The surface of the fin portion (drainage projection) 34 has hydrophobic properties. For example, a hydrophobic material may be used as the material of the fin portion 34, or the surface of the fin portion 34 may be subjected to a process such as attaching a hydrophobic film.

[0031] This allows the surface of the fin portion (water-draining projection) 34 to repel liquid and allows the formed water droplets to slide off easily. Therefore, the amount of water droplets adhering to the surface of the fin portion (water-draining projection) 34 can be reduced.

[0032] The surface of the lower part of the side support 30 may also be hydrophobic. For example, a hydrophobic film may be attached to the surface of the lower part of the side support 30. This makes it possible for the surface of the lower part of the side support 30 to repel liquid and for water droplets that form to slide off easily. Therefore, the amount of water droplets that adhere to the surface of the lower part of the side support 30 can be reduced.

[0033] Furthermore, the side and upper parts of the side support 30 are hydrophilic. Furthermore, the claw parts 32 are hydrophilic. For example, the side support 30 and the claw parts 32 may be made of a hydrophilic material, or the surfaces of the side and upper parts of the side support 30 and the surfaces of the claw parts 32 may be treated by applying a hydrophilic film or the like.

[0034] This allows the liquid to adhere to the surfaces of the sides and upper parts of the side columns 30 and the surfaces of the claw parts 32, making it difficult for water droplets to form. Therefore, it is possible to reduce water droplets adhering to the surfaces of the sides and upper parts of the side columns 30 and the surfaces of the claw parts 32.

[0035] In other words, the hydrophobicity and hydrophilicity are different between the top and bottom of one side support 30 .

[0036] 4 is an enlarged view of the fins (water-draining projections) in the substrate cassette shown in FIG. 2, and FIG. 5 is a diagram showing the flow of drying air and processing liquid in the vicinity of the fins (water-draining projections) shown in FIG.

[0037] 4, the surface of fin portion (drainage protrusion) 34 has an uneven structure. For example, the surface of fin portion 34 may be subjected to uneven processing, or a film having an uneven structure may be attached to the surface of fin portion 34.

[0038] 5, this allows the drying air during drying and the processing liquid during wet processing to flow behind the fins (water drainage protrusions) 34. For example, it is known that dimples on a golf ball increase the amount of air that flows behind the golf ball, regulating the air flow.

[0039] Here, in the wet process, after the substrate cassette 1 is removed from the pure water (rinsing solution), the semiconductor substrates W are dried while still contained in the substrate cassette 1. For example, water droplets on the surfaces of the semiconductor substrates W are removed by blowing dry air onto the semiconductor substrates W from the side of the substrate cassette 1.

[0040] At this time, if water droplets are attached to the side supports 30, the water droplets will be scattered by the drying wind and remain attached to the surface of the semiconductor substrate W. The remaining water droplets during drying cause poor drying in which so-called water marks (drying stains) are formed on the surface of the semiconductor substrate W. An example of a water mark (drying stain) is a granular silicon oxide film (silicate Si(OH)4 formed by the reaction of a silicon substrate with water and oxygen). Water marks (drying stains) become dark spots on the solar cell, which can lead to a decrease in the performance and yield of the solar cell.

[0041] In this regard, according to the substrate cassette 1 of this embodiment, an inverted triangular fin portion (water drainage protrusion) 34 is arranged on the lower portion of the side support 30. This makes it possible to reduce water droplets adhering to the lower portion of the side support 30 when the substrate cassette 1 is removed from the pure water (rinse solution). This makes it possible to reduce water droplets remaining on the semiconductor substrate W during drying due to water droplets adhering to the side support 30, and water marks (drying stains) on the surface of the semiconductor substrate W due to the remaining water droplets on the semiconductor substrate W during drying, i.e., poor drying of the semiconductor substrate W. As a result, it is possible to suppress performance degradation and yield degradation of the solar cell.

[0042] Furthermore, according to the substrate cassette 1 of this embodiment, the surface of the fin portion (water-draining projection) 34 is hydrophobic. This can further reduce water droplets adhering to the fin portion (water-draining projection) 34. This can reduce water droplets remaining on the semiconductor substrate W during drying due to water droplets adhering to the fin portion (water-draining projection) 34, and water marks (drying stains) on the surface of the semiconductor substrate W due to the remaining water droplets on the semiconductor substrate W during drying, i.e., poor drying of the semiconductor substrate W. As a result, it is possible to suppress performance degradation and yield reduction of the solar cell.

[0043] Furthermore, according to the substrate cassette 1 of this embodiment, the side and upper parts of the side columns 30 and the claw parts 32 are hydrophilic. This makes it possible to reduce water droplets adhering to the side and upper parts of the side columns 30 and the claw parts 32. This makes it possible to reduce water droplets remaining on the semiconductor substrate W during drying due to water droplets adhering to the side and upper parts of the side columns 30 and the claw parts 32, and water marks (drying stains) on the surface of the semiconductor substrate W due to the remaining water droplets on the semiconductor substrate W during drying, i.e., poor drying of the semiconductor substrate W. As a result, it is possible to suppress performance degradation and yield degradation of the solar cell.

[0044] Here, the fins (water drainage projections) 34 may impede the flow of drying air during drying, which is expected to cause water droplets to remain on the surface of the substrate.Furthermore, the fins (water drainage projections) 34 may impede the circulation of the processing liquid during the wet process, which is expected to cause uneven processing during the wet process.

[0045] In this regard, according to the substrate cassette 1 of this embodiment, the surface of the fin portion (water-draining protrusion) 34 has an uneven structure, which allows the drying air during drying and the processing liquid during wet processing to flow behind the fin portion (water-draining protrusion) 34, as described above, as shown in FIG.

[0046] Therefore, the fins (water draining projections) 34 can reduce water marks (drying stains) on the surface of the semiconductor substrate W caused by water droplets remaining on the semiconductor substrate W during drying due to the obstruction of drying air, that is, poor drying of the semiconductor substrate W. Furthermore, the fins (water draining projections) 34 can reduce uneven processing in the wet process caused by the obstruction of circulation of the processing liquid during the wet process. As a result, the performance degradation and yield degradation of the solar cell can be suppressed.

[0047] Although the embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiment, and various changes and modifications are possible. For example, in the above-mentioned embodiment, the characteristics of the side supports of the substrate cassette are described, but the characteristics of the side supports of the present invention can also be applied to the lower supports. That is, A plurality of claws are formed on the upper portion of the lower support, which are arranged in the arrangement direction of the substrates, protrude from the upper portion of the lower support, and support each of the substrates so that the substrates are spaced apart from each other; The lower part of the lower support is formed with a fin part (water drainage protrusion) that extends in the direction of the arrangement of the boards and has a cross-sectional shape that protrudes downward in an inverted triangle shape that intersects with the arrangement of the boards, The surface of the fins (water drainage projections) is hydrophobic, The sides and top of the lower strut are hydrophilic; The plurality of claws are hydrophilic, The surface of the fin portion (water drainage protrusion) may have an uneven structure.

[0048] In the above-described embodiment, a substrate cassette for simultaneously immersing a plurality of semiconductor substrates (wafers) in a liquid is exemplified. However, the substrate cassette of the present invention is not limited to this, and can also be used for simultaneously immersing a variety of thin substrates (wafers) in a liquid. [Explanation of symbols]

[0049] 1 PCB Cassette 11 Front plate 12 Back plate 21 Lower strut 30 Lateral struts 32 Claw part 34 Fin section (water draining protrusion) W semiconductor substrate (substrate)

Claims

1. A substrate cassette for arranging a plurality of substrates with their main surfaces facing each other and for simultaneously immersing the plurality of substrates in a liquid, comprising: a plurality of side supports extending in an arrangement direction of the plurality of substrates and supporting side ends of each of the plurality of substrates; a plurality of claws arranged on the sides of the side columns in the arrangement direction, protruding from the sides of the side columns, and supporting each of the plurality of substrates so that the substrates are spaced apart; A drip-watering protrusion is disposed at the lower portion of the side support, extends in the arrangement direction, and has a cross-sectional shape intersecting the arrangement direction that protrudes downward in an inverted triangle shape; Equipped with The surface of the drainage projection is hydrophobic, the sides and top of the side struts are hydrophilic; The surface of the water drainage projection has an uneven structure. Board cassette.

2. The substrate cassette according to claim 1 , wherein the plurality of claws are hydrophilic.

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