JP2005161200A - Filter member for semiconductor gas, and filter apparatus using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter member with superior filtering performance, heat resistance and corrosion resistance, and suitably used for filtration of semiconductor manufacturing gases, in particular, process gases with activity, and a filter apparatus using it. <P>SOLUTION: This filter member for semiconductor gas is formed in a disk-like body having a laminated filter medium containing a membrane-like filtration layer consisting of fine porous polytetrafluoroethylene (PTFE), and protective layers laminated on both sides of the filtration layer and protecting the filtration layer and consisting of PTFE for primary filtration, and having a mesh-like and formable form-keeping body arranged on both sides of the laminated filter medium. The laminated filter medium has a corrugated part having pleats formed by pleating, and its outer periphery part has a flange part compacted by force causing no return of the thickness by plastic deformation of the form-keeping body. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a filter member for semiconductor gas, which is excellent in filtration performance, heat resistance and corrosion resistance, and can be suitably used for filtration of semiconductor manufacturing gas, particularly active process gas, and a filter device using the same. .

  Filter devices used in the field of semiconductor manufacturing have high filtration performance that removes fine particles such as impure fine particles and moisture to the PPT level as semiconductors become finer and more integrated. And heat resistance in the baking process are required, and in order to improve the efficiency of the apparatus, it is required to reduce the installation space by reducing the size and to have good handleability.

Therefore, the filter member used for this generally requires the following characteristics.
(1) The material shall have sufficient corrosion resistance against the processing gas and heat resistance that can withstand baking treatment.
(2) The pressure loss is small and the filtration area is large and the large filtration area can be efficiently filtered.
(3) High pressure resistance and equivalent strength in both forward and reverse directions. (4) The structure shall not be easily deformed or damaged by handling, and can be easily and reliably mounted on the housing.

  The above (1) is a prerequisite for the corrosion resistance to the target gas as described above, as well as the characteristics of having heat resistance that can withstand baking heat treatment for removing impurities such as moisture and hydrocarbons during use. With regard to (2), in order to use the filter device itself within a limited volume, it is possible to perform filtration with excellent filtration efficiency and stability, and the filter member has a diameter as small as possible and can be substantially filtered within a unit area. A filter member capable of increasing the area is desired, and a filter member capable of filtering a large volume of processing fluid while having a small volume is expected.

  Further, (3) and (4) are required when actually incorporated and used in the filter device, and the former (3) has a pressure resistance that can withstand a predetermined filtration pressure as a structure. In addition, even when this is mounted on the housing, the directionality is not particularly concerned, and the versatility applicable to any direction is rich. In the latter case (4), the filter member does not easily lose its shape or requires more care and care than is necessary for mounting, reducing the burden on the operator and improving the product yield.

On the other hand, the semiconductor as the production gas (referred to as a semiconductor gas when), N2, Ar, the He, and a carrier gas comprising an inert gas such as H2, activity, i.e., for example, Cl ₂ with a corrosive, Hcl, such as HF For example, Japanese Patent Application Laid-Open No. 6-63329 has been proposed as a filter device for the carrier gas. As shown in FIG. 7, this proposal is formed as an in-line type by providing threaded portions S at both ends so that it can be directly connected to a pipe or the like. The filter member F of the metal sintered compact which sintered the disk in the shape of a disk is arrange | positioned, and this is distribute | arranged between 1 set of housing pieces H and H which carry out inlay fitting. The filter member F is welded between the housing pieces H and H in a more airtight manner, and the filter member F pressed in advance by heat shrinkage after the formation of the outer peripheral welded portion W is welded. Since the filter member F and the welded portion W are separated from each other in the axial direction, the thermal influence at the time of welding to the filter member F can be reduced.

  However, when the metal filter member F is used, even if a sintered body made of stainless steel having high corrosion resistance is used, it is used as the filter member F when the semiconductor gas is the highly corrosive process gas. Corrosion resistance is not sufficient because various impurities are mixed into the material and segregation occurs in the metal when various processing such as miniaturization, pulverization or sintering is performed, and the specific surface area is large. Absent. For this reason, frequent replacement may increase costs, and there are limitations when using metal filter members with process gas. From the viewpoint of corrosion resistance, it is possible to use nickel as a material for the filter member F. However, since fine powder, fibers of several tens of micrometers, and short fibers are easily mixed with impurities and expensive. It is difficult to obtain the desired corrosion resistance at low cost.

  For this reason, polytetrafluoroethylene (PTFE) is used as the filter member F of the filter device for the active process gas, and as a filter device when using the PTFE filter member F, FIG. The filter member F is also formed as a vertically long cylindrical body.

  In the filter member F of such a conventional filter device, the filtration layer itself is a cylindrical body and is a thin-walled body in a uniaxial and biaxially stretched state for adjusting pores, and itself withstands the filtration pressure. Therefore, therefore, there has been proposed one in which a filtration layer made of PTFE is attached to a breathable cylindrical support (linner) made of a fluororesin that can be injection-molded, for example, perfluoroalkoxy polymer (Prior Document 2). ).

  However, in the case of using a thin-walled body that is in a stretched state, coupled with the fact that it is a cylindrical long body and large-sized, it shrinks and adheres to the liner by heat shrinkage in a high temperature range, but the retainer is made of resin. Therefore, it is easy to soften and the continuous usable temperature is limited to about 120 ° C. Further, since it is supported by the retainer, when the flow direction changes from the retainer side to the filter member F side, the pressure resistance strength is reduced to about 1/5. And since it is large sized, device space efficiency falls.

  A filter member F that pleats the filter member F to increase the filtration area has also been proposed (Prior Document 3). However, corrugated forming is difficult to plastically deform with an organic material such as PTFE, and can easily be spring-backed. It is difficult to achieve the desired typing.

JP-A-6-63329 JP 2001-170424 A JP 9-504737 A

  In view of such a situation, the present invention has sufficient corrosion resistance to a processing gas and heat resistance that can withstand baking treatment, and has a small pressure loss, a large substantial filtration area, and can efficiently filter a large amount of gas fluid. Therefore, it is an object of the present invention to provide a semiconductor gas filter member that can be suitably used for filtering the semiconductor gas, particularly, a process gas, and a filter device using the same.

  In order to achieve the above object, the invention according to claim 1 is a membrane-like filtration layer made of microporous polytetrafluoroethylene (PTFE), and is laminated on both sides of the filtration layer and protects the filtration layer. And a laminated filter medium comprising a protective layer made of PTFE for primary filtration, and a disk-shaped body having a mesh-like and moldable shape-retaining material disposed on both sides of the laminated filter medium, and the laminated filter medium is It has a corrugated portion in which creases caused by crease due to plastic deformation of the shape-retaining body are arranged, and a flange portion reduced in thickness at a strength that does not cause a return of thickness at the outer peripheral edge portion.

  According to a second aspect of the present invention, the shape-retaining body is made of a mesh woven with nickel soft fine wires having a wire diameter of 30 to 120 μm and a proof stress ratio of 15 to 45% (proof strength / tensile strength × 100). The invention according to claim 4 is characterized in that the flange portion is tightly encapsulated with a tape-like sealing material including the outer edge and both surfaces, and the corrugated portion is formed by shrinking the outer peripheral edge portion. According to the thickness, it has a non-parallel portion generated between adjacent folds, and is characterized by improving filtration efficiency.

  According to a fifth aspect of the present invention, in the filter member according to any one of the first to fourth aspects, the flange portion is hermetically sealed between the opposing surfaces of a pair of housing pieces that form an internal flow path and are fitted with a spigot. The internal flow path is blocked by being sandwiched, and the invention according to claim 6 is characterized in that the flange portion is hermetically sealed between the opposing surfaces by heat shrinkage after the outer periphery welding of the spigot fitting portion. It is characterized by being pinched.

  Thus, since the invention according to claim 1 is formed of PTFE, even when the semiconductor gas is a process gas, the filtration layer has a corrosion resistance and has a disk shape, thereby forming a cylindrical shape. As compared with handling and assembly, the size can be reduced and the crease shape can maintain a substantially increased filtration area and increase the gas permeation amount while reducing pressure loss. Further, the pressure resistance can be increased by the folds, and the strength is equivalent in both the forward and reverse directions, and the excellent effect is obtained such that the directionality during mounting can be ignored. Further, as described above, since the flange is formed in a disk shape and firmly integrated on the outer periphery and is uniformly stretched, the deformation of the filtration layer at the time of use can be improved as compared with the conventional product.

  In the invention according to claim 2, the shape-retaining body is made of a mesh woven with nickel soft fine wires having a wire diameter of 30 to 120 μm and a proof stress ratio of 15 to 45%. Prevents impurities from being mixed to maintain corrosion resistance, maintains the corrosion resistance of the filter member, and is soft so that plastic deformation is easy and shape retention by plastic deformation is improved, maintaining the shape of the corrugated part of the filter member. Improve filtration performance.

  According to a third aspect of the invention, the flange portion is tightly encapsulated with a tape-like sealing material including the outer edge and both surfaces, thereby improving the airtightness with the housing. The corrugated portion includes a non-parallel portion generated between adjacent folds due to the reduced thickness of the outer peripheral edge portion, thereby reducing the load for excessive shape retention and maintaining the durability of the filter member. Useful.

  Further, the invention according to claim 5 facilitates the mounting of the filter member, and the invention according to claim 6 is characterized in that the flange portion is hermetically sealed between the opposing surfaces by heat shrinkage after the outer periphery welding of the spigot fitting portion. By being pinched, it is airtight and easy and reliable to incorporate.

Hereinafter, an example of a preferred embodiment of the present invention will be described with reference to the drawings.
The filter member 2 of the present invention includes a laminated filter medium 5 including a thin-film filtration layer 3 and a protective layer 4 laminated on both sides of the filtration layer 3, and a mesh-like and typed arrangement disposed on both sides of the laminated filter medium 5. The corrugated portion 10 having a shape-retaining body 7, for example, a disk-shaped body made of a disk and having pleats 9 arranged therein, and the outer peripheral edge portion thereof are returned to their thickness due to plastic deformation of the shape-retaining body 7. The flange portion 12 is reduced in thickness with no strength.

  The filtration layer 3 is made of polytetrafluoroethylene (PTFE) that can withstand a process gas, which is an active semiconductor gas, and is formed by, for example, a powder forming method proposed by JP-A-10-323923. A sheet material that is stretched in a uniaxial or biaxial direction is used. This is because the combined PTFE powder is stretched into a fiber to form micropores partitioned between the fibers, and the porosity is very high, for example, 50% or more. FIG. 5 shows an example of a very thin film body that is 3000 times larger. As the filtration layer 3, one or more of these membranes are used as necessary, and a composite in which one or more sheets having different characteristics with different hole distributions, hole diameters, and the like are stacked. It may be formed as a filtration layer 3A. Therefore, for example, even if the accuracy is slightly low per sheet, it is preferable to reduce the pressure loss as a whole by using a large number of sheets, and in this case, each filtration layer has pore characteristics. May be different.

  Further, even when a plurality of membranes are used, the filtration layer 3 is a thin membrane having a thickness of, for example, several tens to several hundreds of μm, so that the filtration layer 3 alone can withstand filtration pressure. Therefore, the laminated filter medium 5 is formed by arranging the protective layers 4 and 4 on both sides thereof. This protective layer 4 is preferably made of PTFE, like the filtration layer 3, and has a pore that is coarser than the filtration layer 3 and a relatively thick and sufficient strength that can maintain its own shape, such as PTFE. Porous PTFE papermaking sheets made of short fibers can be used.

  As a preferable configuration of each layer of the laminated filter medium 5, for example, the thickness of the filtration layer 3 is about 10 to 500 μm, preferably about 50 to 200 μm, and a pore diameter of about 0.05 to 3 μm to guarantee a predetermined filtration accuracy, preferably One or a plurality of laminated bodies having a fine pore of 0.1 to 1 μm, and the protective layer 4 has a thickness of, for example, 0.1 to 1 mm (preferably 0.15 to 0.7 mm). And more preferably 0.2 to 0.5 mm), which is thicker than the filtration layer 3, and the pore diameter is larger than the pore diameter of the filtration layer 3, for example, about 5 to 100 μm (preferably about 10 to 60 μm). ). As a result, the overall strength of the laminated filter medium 5 is increased, and the protective layer 4 is pre-filtered (preliminary filtration) prior to the filter layer 3, thereby reducing impurities in the fluid to be treated in advance and extending the filter life. . The specifications are appropriately adjusted depending on the purity of the gas to be processed, the supply state, the size and structure of the filter device, and the like.

  As described above, in the filter member 2, the shape retaining body 7 that molds and retains the multilayer filter medium 5 is disposed on both surfaces of the multilayer filter medium 5. In this embodiment, the shape-retaining body 7 has a high corrosion resistance and a predetermined strength, and can keep the shape of plastic working, for example, a soft thin wire such as a corrosion-resistant stainless steel, nickel, or a nickel alloy, preferably a wire diameter of 50 to 300 μm. , (More preferably 100 to 200 μm), and a plain weave body having a yield strength ratio of 15 to 45% (proof strength / tensile strength × 100) is used. In addition to the plain weave body, various knitted and woven bodies, for example, those having a basis weight of about # 10 to 100, can be used as long as they can exhibit surface protection and shape retention of the laminated filter medium 5. Yield strength refers to stress until 0.2% elongation occurs and is measured as the yield stress of JISZ2241.

  As the mesh used for the shape retaining body 7, the nickel is excellent in corrosion resistance, and even in a soft state, the tensile strength is 200 to 600 MPa, preferably 350 to 600 MPa, for example 450 MPa, the proof strength 80 to 250 MPa, preferably 100 to 200 MPa, For example, it has a characteristic of 151 MPa, an elongation of 25 to 55%, preferably 35 to 50%, for example 42%, and a proof stress ratio (proof stress / tensile strength × 100) of 25 to 55%, for example 33.5%. Is easily obtained, and is suitable for suppressing bending deformation and the phenomenon of shape return after deformation (spring back).

  As a result, as shown in FIG. 3, a laminated body 14 is formed by disposing mesh shape-retaining bodies 7 and 7 on both sides of the laminated filter medium 5 formed by the filtration layer 3 and the protective layers 4 and 4 on both sides thereof. And the disk-shaped filter member 2 which has the corrugated part 10 in which the pleats 9 are arranged, and the flange part 12 whose outer peripheral edge part is reduced is formed by corrugation, thickness reduction and punching of the outer peripheral edge part. .

  The folds 9 are formed side by side by folding the laminated body 14 continuously in a mountain valley by molding, as shown in an enlarged cross section of a small range including the outer peripheral edge in FIG. The substantial filtration area per unit area can be increased, thus increasing the filtration efficiency for a large volume of fluid to be treated, and each surface of the pleat is oriented in the direction to support the fluid flow direction. Therefore, the pressure resistance is improved.

  The pleat 9 is set depending on, for example, the thickness of the laminated filter medium 5 to be used, the size of the filter member 2, and the like, and usually has a pitch of 2 to 15 times, preferably 4 to 8 times the thickness t of the laminated body 14. (P) and the fold depth d is preferably about 3 to 15 mm, for example, when the depth is extremely narrow and deep, that is, the folds are closely contacted with each other at a narrow interval. It is difficult for the fluid to be processed to sufficiently penetrate into the deep part of the valley, and it is difficult to improve the filtration characteristics.

  The shape-retaining body 7 is plastically deformed and molded in the same shape as the folded shape of the laminated filter medium 5 to firmly hold the folded shape to form a pleated sheet, and to form a disk shape to be formed. At the same time, the outer peripheral edge portion is disposed between the upper and lower molds so as to eliminate the processed spring back, and is pressed and reduced in thickness, thereby forming the peripheral reduced thickness portion 15 which is narrowed. A part of the mesh of the shape-retaining body 7 is embedded in the protective layer 4 by this pressure reduction. For example, the peripheral thickness-reduced portion 15 is firmly joined together with the rigidity of the mesh itself, so that the shape can be stably fixed. The disc-shaped filter member 2 having the flange 12 is formed by punching, for example, a circle around the periphery of the filter member.

  As a result, the filter member 2 includes the corrugated portion 10 in which the folds 9 are arranged, and the flange portion 12 in which the outer peripheral edge portion is reduced with a strength that does not cause a return of thickness due to plastic deformation of the shape retaining body 7. Will be included. Further, as the peripheral reduced portion 15 is formed, the crease 9 of the corrugated portion 10 tilts and tilts (the crease 9 is completely tilted and flattened at the peripheral reduced portion 15). Also, due to the difference in thickness reduction between the corrugated portion 10 and the flange portion 12, the corrugated portion 10 also extends to both ends of the pleats 9 and 9 due to the contraction pressure, and increases the inclination toward the periphery to increase the center of the edge. A non-parallel portion 17 that bends or curves in a different direction from the portion of the fold 9 that is relatively parallel to the portion is formed. Thereby, the arrangement | positioning clearance gap of the pleat 9 increases, a to-be-processed fluid fully penetrate | invades even into the trough part of the pleat 9, and filtration efficiency is also improved. Moreover, the height of the pleat 9 is reduced by the tilt accompanying the thickness reduction. In addition, it is good also as the fold 9 of the mountain valley connected in the center part without the fall.

  As shown in FIGS. 1 and 4, the flange portion 12 tightly encapsulates a tape-like sealing material 20 that covers and surrounds the outer edge end surface and both surfaces including the peripheral reduced thickness portion 15. A gap between lines in the mesh-shaped shape retaining body 7 on the surface of the flange portion 12 is sealed. As the sealing material 20, for example, a tape-shaped PTEE film material or a porous tape material is used.

  The filter member 2, for example, various specifications such as outer diameter and corrugated shape can be freely set according to the filtration performance, and the structure is substantially the same in both the front and back directions. It can be used regardless of the reverse direction.

  Next, the filter device 1 using the filter member 2 will be described by taking as an example the case of the inline type filter device shown in FIG. It can be used as a filter device using various disk-shaped filter members, as shown in FIG. 8 and can be used as the filter device 1 for an integrated device proposed by JP-A-11-165012.

  As shown in FIG. 7, the filter device 1 has a flange portion of the filter member 2 between the opposing surfaces of a pair of metal housing pieces H, H that form an internal flow path R and have a split surface that is fitted with an inlay. 12 in a state of being clamped at a position separated from the split surface, the split surface is welded to form the outer peripheral welded portion W, which is further strongly sealed by thermal contraction due to cooling accompanying the dissipation of the welding heat, The internal flow path R is configured to be closed.

  For the pressing, for example, a pressure of about 10 to 100 MPa is applied, the length of the gap for mounting the flange portion 12 is adjusted to such an extent that the pressure is reached, and the outer peripheral weld W does not affect the filter member 2 thermally. Thus, the welding is preferably performed by a method capable of local heating such as electron beam welding while supplying argon gas so that the heating part is not oxidized if necessary. As a result, it is possible to prevent the pore characteristics from being changed or modified by heating the filter member 2.

  In such a filter device 1, the following three types of filter media were produced as the filter member 2 and the filter performance was compared.

  As an example, a filtration layer 3 made of PTFE film material having a pore name (average pore diameter of 0.3 μm, thickness of 25 μm) manufactured by Sumitomo Electric Co., Ltd., and a thickness of 0.4 mm and a pore diameter disposed on both sides thereof are used. A laminated filter medium 5 in which a 30 μm PTFE protective layer 4 is laminated, and a shape retaining body 7 made of a mesh formed by weaving a soft Ni fine wire having a wire diameter of 0.08 mm in 60 # on the surface, Is bent with a mold at an interval of 6 mm and waved, and finally formed so that the crease formation interval is 2.5 mm. The filtration layer 3 has three layers (Example 1) and a pore diameter of 0. A layer (Example 2) in which one layer having a thickness of 1 μm and a thickness of 30 μm was laminated was used.

  The nickel wire used for the shape retaining body 7 has the characteristics of tensile strength 450 MPa, yield strength 151 MPa, elongation 42%, and yield strength ratio (proof strength / tensile strength × 100) of 33.5%. It could be easily bent and deformed, and there was no shape return phenomenon after deformation.

  By setting a sheet of laminated material with creases between the laminated filter medium 5 and the shape retaining body 7 between ring-shaped pressing tools having an outer diameter of 45 mm and an inner diameter of 38 mm, the outer peripheral edge is returned from both the upper and lower directions and pressed so as not to be deformed. The filter member 2 in which the flange portion 12 having the peripheral reduced portion 15 was formed around the corrugated portion 10 was formed. Further, in this case, the inside was pressed, and the fold located on the pressing surface was crushed into a flat state with a total thickness of 0.75 mm. As a result, in the pressing portion, a part of the woven portion (intersection portion of the vertical line and the horizontal line) of the shape retaining mesh infiltrates into the protective layer to provide strong formability, and the shape retaining mesh itself The return phenomenon of the thickness could be restrained by the rigidity.

  Therefore, the pleated shape of the filter member is fixed by the pressing, and the integrity is maintained even if the filter member is handled by hand or cut to a predetermined size, and the fold provides a high filtration area per unit area. In addition, the pressure resistance can be increased to several times or more compared with the flat plate state that does not form the folds, and there is no problem in use with a heat resistance of 250 ° C. or more and excellent corrosion resistance. .

  In addition, the filter member of Example Product 2 is obtained by stacking three filtration layers having a relatively coarse pore diameter in order to reduce filtration resistance, and the processing flow rate per unit area is large while maintaining accuracy. The width has been improved, enabling further miniaturization.

  On the other hand, the comparative product 1 is manufactured by Millipore (product number WGMXMSRR-4) and is formed of a tubular filter member (D: 26 mm × L: 55 mm) as shown in FIG. A comparative example product 2 is constructed by using a filter member made of a conventional stainless steel flat plate-like sintered body, using the same kind of mesh laminated and creased with a width of 5 mm.

  Each of these filter parts is cut into a circular shape having an outer diameter of 40 mm as a filter member for the in-line type filter device shown in FIG. 7, and further, a sealing material having a width of 5 mm including the outer peripheral end surface is wound around and added to the protective layer. Pressure fusion was performed. Thus, the peripheral edge was completely sealed with the sealing material.

  The test results are shown in FIG. 6, and this measurement is the result of examining the relationship with the pressure loss when each filter device is connected to the gas supply pipe and the test gas is sequentially flowed at a predetermined flow rate. Each is converted per unit area.

  As can be seen from this result, it can be seen that the filter of the licensed product 1 is capable of processing the flow rate several times as large as that of other comparative products, and the effect is obtained by using the plurality of filtration layers. This is probably due to the depth filtration. Moreover, in this invention, the influence on the filtration layer at the time of pressing together with a pre-filtration by interposing a protective layer between a filtration layer and a shape-retaining body can be relieved. Therefore, although the filter member of the comparative product 1 is pleated with the protective mesh, when the inner part is disassembled, the convex portion of the mesh directly presses the adjacent filtration layer to form an indentation. Such problems have been improved, and this is favorable for quality stability.

In addition, in the above-described embodiment, the filtration layer per sheet has a slightly lower porosity, but the pressure loss is suppressed by laminating several sheets so as to be a depth filtration as a whole, and the filtration characteristics per unit area are improved. Compared with the filtration area when obtaining a predetermined treatment flow rate, for example, the filter of the comparative product 1 is 250 m ² , whereas the product of the present invention can be 60 cm ² , and is about ¼. There is an advantage that can be made compact in size.

It is a partially broken top view which illustrates embodiment of the filter member which showed only a part of shape retaining body. It is the front view. It is sectional drawing which illustrates a laminated filter medium. It is sectional drawing which illustrates the laminated filter medium of a waved state. It is 3000 times enlarged plan views which illustrate a filtration layer. It is a diagram which illustrates a flow characteristic result. It is a partial sectional view showing an example of a filter device. It is sectional drawing which shows the other example of a filter apparatus. It is sectional drawing which illustrates the conventional filter member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Filter apparatus 2 Filter member 3 Filtration layer 4 Protective layer 5 Laminated filter media 7 Shaped body 9 Folding 10 Corrugated part 12 Flange part 14 Laminated body 15 Reduced peripheral edge part 17 Non-parallel part 20 Seal material

Claims (6)

Lamination comprising a membrane-like filtration layer made of microporous polytetrafluoroethylene (PTFE) and a protective layer made of PTFE laminated on both sides of the filtration layer and protecting the filtration layer and performing primary filtration A disk-shaped body having a mesh-shaped and moldable shape-retaining body disposed on both sides of the filter medium and the laminated filter medium,
The laminated filter medium has a corrugated portion in which creases are arranged by crease, and an outer peripheral edge portion thereof has a flange portion reduced in thickness so as not to cause a return of thickness due to plastic deformation of the shape retaining body. A filter member for semiconductor gas.   2. The filter member for semiconductor gas according to claim 1, wherein the shape-retaining body is made of a mesh woven of nickel soft fine wires having a wire diameter of 30 to 120 μm and a proof stress ratio of 15 to 45%.   The filter member for semiconductor gas according to claim 1 or 2, wherein the flange portion is tightly encapsulated with a tape-like sealing material including an outer edge end surface and both surfaces continuous therewith.   The semiconductor corrugated filter member according to claim 1, wherein the corrugated portion includes a non-parallel portion generated between adjacent folds due to a reduction in thickness of the outer peripheral edge portion.   The filter member according to any one of claims 1 to 4, wherein the flange portion is airtightly sandwiched between opposing faces of a pair of housing pieces that form an internal flow path and are fitted with a spigot. A filter device for semiconductor gas, which is cut off.   6. The semiconductor gas filter device according to claim 5, wherein the flange portion is sandwiched between the opposing surfaces in an airtight manner by heat shrinkage after the outer periphery welding of the spigot fitting portion.

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