Method for manufacturing a housing for mounting a semiconductor element and mold release film

Abstract

Method for manufacturing a housing for mounting a semiconductor element by using a forming tool with an upper tool and a lower tool, wherein the housing for mounting a semiconductor element comprises a substrate having a mounting surface for mounting a semiconductor element, and an encapsulation body formed from a cured product of a curable resin and having a frame-shaped section surrounding the mounting surface, and wherein the housing has a concave section formed by the mounting surface and the encapsulation body, and the method for manufacturing a housing for mounting a semiconductor element comprises: a step of arranging a mold release film, having a substantially constant thickness across the film, on the upper tool, which has a convex section whose shape corresponds to the concave section, arranging the substrate on the lower tool, and closing the upper and lower tools so that the convex section is in close contact with the mounting section of the substrate by means of the mold release film, a step of filling a space formed between the upper tool and the lower tool with a curable resin, whereupon the curable resin is cured, and a step of separating a cured product of the curable resin together with the substrate from the mold tool, wherein the mold release film comprises a first layer, which is intended to be in contact with the curable resin at the time of curing of the curable resin, and a second layer, the first layer has a thickness of 3 to 25 µm and furthermore has a tensile energy storage modulus at 180 °C of 10 to 40 MPa and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and a thickness (µm) of 2000 to 13000.

Description

TECHNICAL AREA

[0001] The present invention relates to a method for manufacturing a housing for mounting a semiconductor element and a mold tool release film for use in the manufacturing process.

[0002] In recent years, a semiconductor package with a hollow structure (hereinafter referred to as a hollow package) for mounting a semiconductor device, such as a solid-state imaging device or MEMS (microelectromechanical systems), has become known. To reduce costs, a resin is used as the package base (an encapsulation body). Furthermore, a DIP (dual inline package) is predominantly used as the package structure; however, in recent years, a SOP (small outline package) or QFP (quad flat package), which is a surface-mount type, has also been used. Additionally, a non-leaded package structure, such as a SON (small outline non-leaded package) or a QFN (quad flat non-leaded package), has been investigated, as a hollow package must be small in size and thickness. Therefore, surface-mount techniques for hollow packages are also being explored.

[0003] A known hollow enclosure can be, for example, an enclosure obtained by forming an encapsulation body with a frame-shaped section surrounding the mounting surface on a substrate (such as a printed circuit board or a terminal frame) that has a mounting surface for mounting a semiconductor element, using a curable resin, and closing an opening of the concave section formed by the mounting surface and the frame-shaped section with a lid.

[0004] A method for manufacturing a hollow housing was proposed, in which, as described in the Fig.As shown in Figure 12, the convex section 200, which corresponds to a shape intended to be a cavity and is formed on the cavity surface of the upper tool 202, is pressed directly onto a section of the connecting frame 206, which is made of metal and is arranged on the lower tool 204. In this state, a space between the upper tool 202 and the lower tool 204 is filled with the resin 208, after which molding (injection molding) is carried out. (e.g., patent document 1).

[0005] However, such a procedure can cause so-called "resin burrs" because the injected resin 208 is likely to penetrate into a space between the convex section 200 and the connection frame 206 if the adhesion between the convex section 200 and the connection frame 206 is poor. In particular, the thickness of the connection frame 206 tends to be uneven, and therefore resin burrs may form in some areas of the connection frame 206 while other areas are free of them. If clamping pressure is increased to prevent resin burrs, other problems arise, such as a dent or depression in the connection frame 206 or damage to the connection frame 206.

[0006] As a further method for producing a hollow housing, a method has been proposed in which an upper tool having a flat cavity surface is used instead of the upper tool 202, which has the convex section 200 on the cavity surface, and a mold release film integrated with a convex section corresponding to the shape of the cavity is arranged on the cavity surface of the mold release film, whereupon the aforementioned convex section is pressed onto a part that is to be exposed by a connecting frame, whereby an injection molding process is carried out (Patent Document 2). According to this method, the convex section can be pressed only weakly onto the connecting frame, since the convex section of the mold release film has a low modulus of elasticity compared to a mold, and therefore resin burrs or damage can be prevented.

[0007] However, such a procedure requires an integrated step of forming a convex section on a mold release film, and such a step is laborious. Furthermore, the convex section, produced from a resin, is more likely to have uneven thickness, and therefore resin burrs may form in some areas while other areas remain free of them. By increasing the clamping pressure to prevent resin burrs, the tip of the convex section 212 of the mold release film 210 can be compressed and project into a space to be filled with the resin 208, as described in the Fig.Figure 13 shows that if injection molding is performed under these conditions, the protruding section can penetrate the encapsulation body, potentially leading to separation failure of the encapsulation body. Furthermore, the shape of the encapsulation body may also be degraded.

[0008] Another method for manufacturing a hollow housing was proposed, in which, as described in the Fig. Figure 14 shows a wall 214, made of a resin, which is formed beforehand around a section that is to be exposed by the connecting frame 206, and the convex section 200 of the upper tool 202 is pressed onto the wall 214 to carry out the injection molding (Patent Document 3). In this process, the wall 214 prevents the resin 208 from escaping from a section that is to be exposed by the connecting frame 206.

[0009] However, since such a procedure requires an additional step of forming the wall 214 during the processing of the connecting frame 206, this step is consequently laborious, and furthermore, if the wall 214 has an uneven height, resin ridges may be formed in some areas.

[0010] Patent document 4 describes a method for using a separating film for resin encapsulation of a semiconductor device. Patent document 5 describes a separating film for a semiconductor encapsulation process, which is placed between a semiconductor chip and the inner surface of a mold when the semiconductor chip is placed in the mold and resin is injected into the mold, and a method for producing a resin-encapsulated semiconductor using the same. DOCUMENTS ON THE STATE OF TECHNICAL PATENT DOCUMENTS Patent Document 1: JP 2006-128354 A Patent Document 2: JP 2007-81307 A Patent Document 3: JP 2010-10227 A Patent document 4: US 7,439,101 B2 Patent Document 5: JP 2010-208104 A REVELATION OF THE INVENTIONAL PROBLEM

[0011] The object of the present invention is to provide a method for manufacturing a housing for mounting a semiconductor element using a mold, wherein the housing for mounting a semiconductor element comprises a substrate having a mounting surface for mounting a semiconductor element, and an encapsulation body formed from a cured product of a curable resin and having a frame-shaped section surrounding the mounting surface, and wherein the housing has a concavity formed by the mounting surface and the encapsulation body, wherein the method makes it possible to prevent the formation of dents or damage to a substrate, the occurrence of failure during separation from a mold, and the formation of resin burrs, and the object of the present invention is to provide a mold release film.which can be used appropriately for the manufacturing process. SOLUTION TO THE PROBLEM

[0012] The present invention provides a method for manufacturing a housing for mounting a semiconductor element and a mold tool release film, which have the following structure [1] to

[10] . [1] Method for manufacturing a housing for mounting a semiconductor element by using a forming tool with an upper tool and a lower tool, wherein the housing for mounting a semiconductor element comprises a substrate having a mounting surface for mounting a semiconductor element, and an encapsulation body formed from a cured product of a curable resin and having a frame-shaped section surrounding the mounting surface, and wherein the housing has a concave section formed by the mounting surface and the encapsulation body, and the method for manufacturing a housing for mounting a semiconductor element comprises: a step of arranging a mold release film, having a substantially constant thickness across the film, on the upper tool, which has a convex section whose shape corresponds to the concave section, arranging the substrate on the lower tool, and closing the upper and lower tools so that the convex section is in close contact with the mounting section of the substrate by means of the mold release film, a step of filling a space formed between the upper tool and the lower tool with a curable resin, whereupon the curable resin is cured, and a step of separating a cured product of the curable resin together with the substrate from the mold tool. [2] Method for manufacturing a housing for mounting a semiconductor element according to [1], wherein the mold release film comprises a first layer, which is intended to be in contact with the curable resin at the time of curing of the curable resin, and a second layer, the first layer has a thickness of 3 to 25 µm and furthermore has a tensile energy storage modulus at 180 °C of 10 to 50 MPa and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and a thickness (µm) of 2000 to 13000. [3] Method for manufacturing a housing for mounting a semiconductor element according to [2], the first layer has a thickness of 5 to 12 µm and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and a thickness (µm) of 3000 to 8000. [4] Method for manufacturing a housing for mounting a semiconductor element according to claim [2] or [4], wherein the mold release film further comprises a third layer which is intended to be in contact with the mold at the time of curing of the curable resin, and the third layer has a thickness of 3 to 25 µm and furthermore has a ratio of the tensile energy storage modulus at 25 °C to the tensile energy storage modulus at 25 °C of the first layer (i.e., tensile energy storage modulus at 25 °C of the third layer / tensile energy storage modulus at 25 °C of the first layer) of 0.5 to 2. [5] Molding tool release film for use in the process for manufacturing a housing for mounting a semiconductor element as defined in [1], wherein the mold release film comprises a first layer, which is to be in contact with the curable resin at the time of curing of the curable resin, and a second layer, wherein the first layer has a thickness of 3 to 25 µm and furthermore has a tensile energy storage modulus at 180 °C of 10 to 50 MPa and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and a thickness (µm) of 2000 to 13000. [6] Mold release film according to [5], the first layer has a thickness of 5 to 12 µm and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and a thickness (µm) of 3000 to 8000. [7] Mold release film according to [5] or [6], which further comprises a third layer which is intended to be in contact with the mold at the time of curing of the curable resin, wherein the third layer has a thickness of 3 to 25 µm and furthermore has a ratio of the tensile energy storage modulus at 25 °C to the tensile energy storage modulus at 25 °C of the first layer (i.e., tensile energy storage modulus at 25 °C of the third layer / tensile energy storage modulus at 25 °C of the first layer) of 0.5 to 2. [8] Mold release film according to one of [5] to [7], wherein a resin forming the first layer is at least one member selected from the group consisting of a fluoropolymer, a polystyrene and a polyolefin having a melting point of at least 200 °C. [9] Mold release film according to one of [5] to [8], wherein a resin forming the second layer is at least one member selected from the group consisting of an unstretched polyamide, a biaxially stretched polyamide, a polybutylene terephthalate, a polyethylene terephthalate and a highly moldable polyethylene terephthalate.

[10] Mold release film according to one of [5] to [9], wherein a resin forming the third layer is at least one member selected from the group consisting of a fluoropolymer, a fluorinated resin, an acrylic rubber, a thermosetting silicone, a polyester, a polyamide, a polystyrene, an ethylene / vinyl alcohol copolymer and a polyolefin having a melting point of at least 200 °C. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0013] According to the present invention, when manufacturing a housing for mounting a semiconductor element using a mold, wherein the housing for mounting a semiconductor element comprises a substrate having a mounting surface for mounting a semiconductor element and an encapsulation body formed from a cured product of a curable resin and having a frame-shaped section surrounding the mounting surface, wherein the housing has a concave section formed by the mounting surface and the encapsulation body, even if the height of the mounting surface of the substrate (such as e.g.a connecting frame), which is arranged on the lower part of the mold, is uneven, and furthermore, even if the height of the convex section of the upper part is uneven, such uniformity is compensated for by a mold release film arranged on the convex section of the upper part, and resin burrs can be suppressed across the entire mounting surface. Resin burrs can be suppressed even at such low clamping pressures that the formation of dents or damage to the substrate is prevented.

[0014] Therefore, according to the present invention, a housing for mounting a semiconductor element, which is free from dents or damage to a substrate and is free from resin burrs on the entire mounting surface of the substrate, can be manufactured simply and stably. BRIEF DESCRIPTION OF THE DRAWINGS Fig.Figure 1 is a schematic cross-sectional view showing an example of a housing for mounting a semiconductor element, which is obtainable by the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig. Figure 2 is a perspective view showing a housing for mounting a semiconductor element that is located in the Fig. 1 is shown. Fig. Figure 3 is a schematic cross-sectional view showing another example of a housing for mounting a semiconductor element, which is obtainable by the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig. Figure 4 is a cross-sectional view showing an example of a forming tool used in the first embodiment of the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig. Figure 5 is a schematic cross-sectional view showing a step (α1) in the first embodiment of the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig. Figure 6 is a schematic cross-sectional view showing a step (α2) in the first embodiment of the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig. Figure 7 is a schematic cross-sectional view showing a step (α3) in the first embodiment of the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig. Figure 8 is a schematic cross-sectional view showing a step (α4) in the first embodiment of the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig.Figure 9 is a schematic cross-sectional view showing a step (α5) in the first embodiment of the method for manufacturing a housing for mounting a semiconductor element of the present invention. Fig. Figure 10 is a schematic cross-sectional view showing the first embodiment of the mold release film of the present invention. Fig. Figure 11 is a schematic cross-sectional view showing the second embodiment of the mold release film of the present invention. Fig. Figure 12 is a schematic cross-sectional view to illustrate an example of a conventional method for manufacturing a hollow housing. Fig. Figure 13 is a schematic cross-sectional view to illustrate another example of a conventional method for manufacturing a hollow enclosure and related problems. Fig.Figure 14 is a schematic cross-sectional view to illustrate another example of a conventional method for manufacturing a hollow housing. DESCRIPTION OF EXECUTION FORMS

[0015] In this description, the following terms are used with the following meanings.

[0016] “Units” in a resin refers to structural units (monomer units) that form the resin.

[0017] A "fluorinated resin" refers to a resin that contains fluorine atoms in its structure.

[0018] The thickness of the mold release film, the thickness of a layer (such as a first layer or a second layer) that forms a mold release film with a multilayer structure, and the tensile storage modulus at 180 °C are each measured by the examples described in the methods.

[0019] The arithmetic mean roughness (Ra) is the arithmetic mean roughness measured according to JIS B0601: 2013 (ISO4287: 1997, Amd.1: 2009). The standard length Ir (limit λc) for the roughness curve was set to 0.8 mm. [Method for manufacturing a housing for mounting a semiconductor element]

[0020] The method for manufacturing a housing for mounting a semiconductor element according to the present invention is a method for manufacturing a housing for mounting a semiconductor element by using a forming tool with an upper tool and a lower tool. wherein the housing for mounting a semiconductor element comprises a substrate having a mounting surface for mounting a semiconductor element, and an encapsulation body formed from a cured product of a curable resin and having a frame-shaped section surrounding the mounting surface, and wherein the housing has a concave section formed by the mounting surface and the encapsulation body, and the method for manufacturing a housing for mounting a semiconductor element comprises: a step of arranging a mold release film, having a substantially constant thickness across the film, on the upper tool, which has a convex section whose shape corresponds to the concave section, arranging the substrate on the lower tool, and closing the upper and lower tools so that the convex section is in close contact with the mounting section of the substrate by means of the mold release film, a step of filling a space formed between the upper tool and the lower tool with a curable resin, whereupon the curable resin is cured, and a step of separating a cured product of the curable resin together with the substrate from the mold tool. [Housing for mounting a semiconductor element]

[0021] A housing for mounting a semiconductor element, which is to be produced by the method for producing a housing for mounting a semiconductor element of the present invention, is not specifically limited as long as it has the aforementioned substrate and the aforementioned encapsulation body, and it can advantageously be selected from known housings for mounting a semiconductor element.

[0022] The Fig. Figure 1 is a schematic cross-sectional view showing an example of a housing for mounting a semiconductor element, obtainable by the method for manufacturing a housing for mounting a semiconductor element according to the present invention. Fig. Figure 2 is a perspective view showing the housing for mounting a semiconductor element, which is located in the Fig. 1 is shown.

[0023] The housing 110 for mounting a semiconductor element comprises the substrate 10 and the encapsulation body 12, which is formed from a curable resin. The substrate 10 is a printed circuit board and has a mounting surface 10a on which a semiconductor element is to be mounted. The substrate 10 is provided with an inner terminal (not shown) on the mounting surface 10a and an outer terminal (not shown) on the surface opposite the side of the mounting surface 10a, and the inner and outer terminals are electrically connected. The encapsulation body 12 is a frame-shaped section that surrounds the mounting surface 10a.

[0024] In the housing 110 for mounting a semiconductor element, the concave section 14 for mounting a semiconductor element is formed by the substrate 10 and the encapsulation body 12. A semiconductor element is arranged on the lower surface (mounting surface 10a) of the concave section 14 in the housing 110, the semiconductor element and the internal terminal are electrically connected, and an opening of the concave section 14 is closed with a cover, thereby obtaining a semiconductor device in which the semiconductor element is mounted on a hollow section of the housing.

[0025] The Fig.Figure 3 is a schematic cross-sectional view showing another example of a housing for mounting a semiconductor element, which has been produced by the method for producing a housing for mounting a semiconductor element of the present invention.

[0026] The housing 120 for mounting a semiconductor element comprises the substrate 16 and the encapsulation body 18, which is formed from a curable resin. The substrate 16 is a terminal frame having the inner terminal 16a, the outer terminal 16b and the chip contact point 16c, and the inner terminal 16a and the outer terminal 16b are electrically connected.

[0027] The encapsulation body 18 has a frame-shaped section 18a that surrounds the mounting surface (the upper surface of the inner connector 16a and the upper surface of the chip contact point 16c) of the substrate 16 and the lower section 18b.

[0028] In the housing 120 for mounting a semiconductor element, a concave section 20 is formed for mounting a semiconductor element through the inner connection 16a and the chip contact point 16c of the substrate 16 and the lower section 18b and the frame-shaped section 18a of the encapsulation body 18.

[0029] A semiconductor element is arranged on the lower surface (the upper surface of the chip contact point 16c) of the concave section 20 in the housing 120 for mounting a semiconductor element, the semiconductor element and the inner connection 16a are electrically connected and an opening of the concave section 20 is closed with a cover, thereby obtaining a semiconductor device in which the semiconductor element is mounted on a hollow section of the housing having the hollow section.

[0030] Examples of semiconductor elements that can be mounted in the housing for mounting a semiconductor element include various sensors. (First embodiment)

[0031] As an embodiment of the method for manufacturing a housing for mounting a semiconductor element according to the present invention, a case is described in detail in which the housing 110 is used for mounting a semiconductor, as described in the Fig. Figure 1 shows a housing produced by injection molding. The method for producing a housing for mounting a semiconductor element according to the embodiment of the present invention comprises the following steps (α1) to (α6). (α1) A step of arranging a mold release film having a substantially constant thickness over the film on an upper tool of a mold comprising the upper tool and the lower tool, wherein the upper tool has a cavity with a plurality of convex sections on the cavity surface, and the lower tool has a substrate arranging section for arranging a substrate such that the cavity of the upper tool is covered by the mold release film, (α2) a step of vacuum suction of the mold tool release film onto the side of the cavity surface of the upper tool, (α3) a step of arranging a substrate having a plurality of mounting surfaces on a substrate arranging section of the lower tool, such that the side opposite the plurality of mounting surfaces is directed towards the side of the lower tool, closing the upper tool and the lower tool, such that the plurality of convex sections of the upper tool are each in close contact with the plurality of mounting surfaces of the substrate by means of the mold tool release film, (α4) a step of filling a space formed between the upper tool and the lower tool with a curable resin, whereupon curing takes place, resulting in a structure comprising the substrate and a cured product of the curable resin, (α5) a step of removing the structure from the mold and (α6) a step of cutting the substrate and the cured product of the structure, so that the majority of the mounting surfaces are separated, thereby obtaining the housing 110 for mounting a semiconductor element. Forming tool:

[0032] The forming tool in the first embodiment can, for example, be a forming tool comprising the upper tool 50 and the lower tool 52, as shown in the Fig.Figure 4 shows that the upper tool 50 has a cavity 54 and a concave resin injection section 60 for introducing the curable resin 40 into the cavity 54. The cavity 54 has a shape corresponding to the shape of the cured product to be formed on the substrate in step (α4), and a plurality of convex sections 56, which have a shape that is an inverse of the concave section 14 in the housing 110 for mounting a semiconductor element, are formed on the cavity surface of the upper tool 50.

[0033] The lower tool 52 is formed with the substrate arrangement section 58 for arranging a substrate and the resin arrangement section 62 for arranging a curable resin. Furthermore, the piston 64 for pushing a curable resin to the resin injection section 60 of the upper tool 50 is arranged in the resin arrangement section 62. Step (α1):

[0034] As it is in the Fig. As shown in Figure 5, the mold release film 30 is arranged to cover the cavity 54 of the upper mold 50. The mold release film 30 is preferably arranged to completely cover the cavity 54 and the resin injection section 60. The mold release film 30 is drawn through the unwind roller (not shown) and a winding roller (not shown), thereby arranging it to cover the cavity 54 of the upper mold 50 in a stretched state.

[0035] A mold release film 30 with a substantially constant thickness across the film is used. A substantially constant thickness across the film means that the difference between the maximum and minimum thickness values ​​when measured at 1 m in a machine direction and a transverse direction of the film, as measured according to ISO 4591:1992 (Method A of JIS K7130:1999, thickness determination by mechanical probing), is at most 15% of the respective average values. The mold release film 30 is described in detail below. Step (α2):

[0036] As it is in the Fig.As shown in Figure 6, the space between the upper tool 50 and the mold release film 30 (i.e., a space between the mold release film 30 and the cavity surface and the inner wall of the resin injection section 60 of the upper tool 50) was evacuated by vacuum suction through a groove (not shown) formed outside the cavity 54 of the upper tool 50, so that the mold release film 30 is stretched, deformed and vacuum adsorbed onto the cavity surface of the upper tool 50.

[0037] Depending on its mechanical strength and thickness, the mold release film 30 does not always have to be in close contact with the cavity surface in a high-temperature environment and the shape of the cavity 54. As described in the Fig.As shown in Figure 6, a small cavity may remain between the mold tool release film 30 and the cavity surface during the vacuum suction stage in step (α2). Step (α3):

[0038] As it is in the Fig. As shown in Figure 7, the substrate 10A, which has a plurality of mounting surfaces (not shown), is arranged on the substrate arrangement section 58, and the upper tool 50 and the lower tool 52 are clamped such that the majority of the convex sections 56 of the upper tool 50 are in close contact with the majority of the mounting surfaces 10A by means of the mold release film. Furthermore, the curable resin 40 is pre-arranged on the piston 64 of the resin arrangement section 62.

[0039] The clamping pressure at the moment of clamping of the upper tool 50 and the lower tool 52 is such that the mold release film 30, which is sandwiched between the convex section 56 and the substrate 10A, is not excessively compressed, so that it does not protrude onto the side of the cavity 54. This prevents separation failure of the cured product due to penetration of a section of the mold release film 30 protruding onto the side of the cavity 54 into a cured product of the curable resin 40. Furthermore, dents or damage to the mounting surface of the substrate 10A can also be prevented.

[0040] In particular, the clamping force is preferably from 10 to 80 tons, more preferably from 20 to 70 tons. The pressure per unit area is preferably from 25 to 200 MPa, more preferably from 50 to 175 MPa.

[0041] It is less likely that the mold release film 30 used in the present invention, which has a substantially constant thickness across the film, will protrude as described above, even when the clamping pressure is increased, compared to a case where a mold release film has an integrated convexity, as shown in the aforementioned patent document 2. By increasing the clamping pressure within a range where no dents or damage to the substrate 10A are formed, the resin burr prevention effect is excellent.

[0042] Various curable resins used in the manufacture of semiconductor packages, etc., can be used as the curable resin 40. A thermosetting resin, such as an epoxy resin or a silicone resin, is preferred, and an epoxy resin is particularly preferred. Examples of suitable epoxy resins include SUMIKON EME G770H type F ver. GR, manufactured by Sumitomo Bakelite Co., Ltd., and T693 / R4719-SP10, manufactured by Nagase ChemteX Corporation. Examples of commercially available silicone resins include LPS-3412AJ and LPS-3412B, manufactured by Shin-Etsu Chemical Co., Ltd.

[0043] The curable resin 40 may contain soot, quartz glass, crystalline silicon dioxide, aluminum oxide, silicon nitride, aluminum nitride, etc. Step (α4):

[0044] As it is in the Fig.As shown in Figure 8, the piston 64 of the lower tool 52 is pushed upwards, so that the curable resin 40 is filled into the cavity 54 through the resin injection section 60. The mold is then heated to cure the curable resin 40.

[0045] In step (α4), when the curable resin 40 is filled into the cavity 54, the mold release film 30 is further pressed, stretched, and deformed by the resin pressure against the side of the cavity surface of the upper tool 50, so that it comes into close contact with the cavity surface. Therefore, a formed cured product will have a shape that corresponds to the shape of the cavity 54.

[0046] The heating temperature of the mold tool at the time of curing of the curable resin 40, i.e., the heating temperature of the curable resin 40, is preferably from 100 to 185 °C, particularly preferably from 140 to 175 °C. If the heating temperature is at least the lower limit in the aforementioned range, the productivity of the housing 110 for mounting a semiconductor element is improved. If the heating temperature is at most the upper limit in the aforementioned range, decomposition of the curable resin 40 is prevented. With a view to suppressing a change in the shape of the cured product due to thermal expansion of the curable resin 40, heating is preferably carried out at the lowest possible temperature within the aforementioned range when the protection of the semiconductor housing 110 for mounting a semiconductor element is particularly necessary.

[0047] The resin pressure at the time of filling with the curable resin 40 is preferably from 2 to 30 MPa, particularly preferably from 3 to 10 MPa. If the resin pressure is at least the lower limit in the aforementioned range, it is unlikely that a disadvantage such as insufficient filling of the curable resin 40 will occur. If the resin pressure is at most the upper limit in the aforementioned range, a semiconductor package 110 for mounting a semiconductor element of excellent quality can be easily obtained. The resin pressure of the curable resin 40 can be adjusted by the piston 64. Step (α5):

[0048] As it is in the Fig. As shown in Figure 9, the structure 110A, which was formed in step (α4), is removed from the mold.

[0049] Structure 110A comprises substrate 10A and the cured product 12A of the curable resin 40, which has cured in the cavity 54. When structure 110A is removed from the mold, the cured product 19 of the curable resin 40, which has cured in the resin injection section 60, is bonded to the cured product 12A of structure 110A. This cured product 19 is cut off after structure 110A has been removed from the mold.

[0050] At the time of filling the curable resin 40 in step (α4), the mounting surface of the substrate 10A is in close contact with the mold release film 30, and therefore the curable resin 40 is not in contact with it. Accordingly, the cured product 12A is formed such that it surrounds and exposes the majority of the respective mounting surfaces of the substrate 10A. Thus, in the structure 110A, a majority of concave sections 14 are formed by the substrate 10A and the cured product 12A surrounding the majority of the respective mounting surfaces. Step (α6):

[0051] The substrate 10A and the cured product 12A of the structure 110A obtained in step (α5) are cut (separated) so that the majority of concave sections 14 of the structure 110A are individually separated, thereby obtaining the housing 110 for mounting a semiconductor element comprising the substrate 10 having at least one mounting surface 10a and the frame-shaped encapsulation body 12 surrounding the mounting surface 10a.

[0052] Such singulation can be carried out using a known method, such as a sawing process (“dicing” process). The sawing process is a method of cutting an object by rotating a saw blade. Typically, a rotating blade (diamond saw blade) is used, which has diamond powder sintered onto the outer circumference of a disc. Singulation by the sawing process can be carried out, for example, by a method in which the object to be cut (structure 110A) is fixed to the processing table by means of a clamping device, and the saw blade is rotated in a state where there is space for inserting the saw blade between the clamping device and the cutting area of ​​the object to be cut.

[0053] In step (α6) after the step (cutting step) of cutting the object to be cut, a foreign material removal step of moving the processing table can be included while a liquid is supplied to the object to be cut from a nozzle located at a position separate from the housing for covering the saw blade.

[0054] The method for manufacturing a housing for mounting a semiconductor element of the present invention has been described above with reference to the first embodiment; however, the present invention is not limited to the first embodiment described above. The respective designs, combinations thereof, etc., in the above embodiment are exemplary, and additions, omissions, substitutions, and other modifications are possible within a range that does not deviate from the concept of the present invention.

[0055] For example, the timing of the detachment of structure 110A from the mold release film 30 is not limited to the time of removing structure 110A from the mold, and structure 110A can be removed from the mold together with the mold release film, and then the mold release film can be detached from structure 110A.

[0056] The mounting surface of the substrate 10, which is positioned on the lower tool 52, may be a [missing word - likely "square" or "square"]. In this case, step (α6) does not need to be performed.

[0057] If the substrate 10 has a plurality of mounting surfaces, the distance between the plurality of the respective mounting surfaces can be uniform or non-uniform. Furthermore, the respective shapes of the plurality of mounting surfaces can be the same or different.

[0058] After step (α6) (or before step (α6) and after step (α5)) a step to form a printing ink layer by applying a printing ink to the surface of the encapsulation body 12 (or the cured product 12A) can be carried out to specify optional information.

[0059] The information to be conveyed by the ink layer is not specifically limited, and can include a serial number, manufacturer information, component type, etc. The ink itself is not specifically limited and can be selected from a range of available inks.

[0060] The method for applying the printing ink is not specifically limited and, for example, various printing methods can be used, such as inkjet printing, screen printing, transfer from a rubber plate, etc.

[0061] In order to form the printing ink layer, a method is preferred in which a light-curable printing ink is used, wherein the printing ink is applied to the surface of the encapsulation body 12 by an inkjet process and cured by irradiation with light.

[0062] A light-curable printing ink typically consists of a material containing a polymerizable compound (monomer, oligomer, etc.). Depending on the requirements, the ink can be combined with a colorant, such as a pigment or dye, a liquid medium (solvent or dispersant), a polymerization inhibitor, a photopolymerization initiator, and various other additives. Other additives include, for example, a lubricant, a polymerization accelerator, a penetration enhancer, a wetting agent (humectant), a fixative, a fungicide, a preservative, an antioxidant, a radiation absorber, a chelating agent, a pH adjuster, a thickener, etc.

[0063] Examples of light used to cure light-curable printing ink include ultraviolet rays, visible rays, infrared rays, an electron beam, or electron beams.

[0064] Examples of light sources for ultraviolet rays include a germicidal lamp, an ultraviolet fluorescent lamp, a carbon arc lamp, a xenon lamp, a high-pressure mercury lamp for copying, a medium-pressure or high-pressure mercury lamp, a super-high-pressure mercury lamp, an electrodeless lamp, a metal halide lamp, an ultraviolet light-emitting diode, an ultraviolet laser diode, or natural light.

[0065] Light irradiation can be carried out under normal pressure or reduced pressure. It can also be performed in air or in an inert gas atmosphere, such as a nitrogen or carbon dioxide atmosphere.

[0066] Furthermore, a housing for mounting a semiconductor element, which has been produced by the method for producing a housing for mounting a semiconductor element of the present invention, is not limited to the housing 110 for mounting a semiconductor element and it can be, for example, a housing 120 for mounting a semiconductor element.

[0067] The housing 120 for mounting a semiconductor element can be manufactured in the same way as in the first embodiment, except that the substrate 16 is used instead of the substrate 10 and the shape of the convex section 56 is changed according to the concave section 20. [Mold tool release film]

[0068] The mold release film 30 in the present invention can be a single-layer structural film or a multi-layer structural film.

[0069] The mold release film 30 must exhibit releaseability, heat resistance that is resistant to the temperature of the mold during molding (typically from 150 to 180 °C), and mechanical strength that is resistant to the pressure or fluidity of the curable resin.

[0070] In the case of the single-layer structural film, the mold release film 30 is preferably, with regard to releaseability, heat resistance, mechanical strength, and elongation at high temperature, a film made of at least one resin selected from the group consisting of a fluoropolymer and a polyolefin having a melting point of at least 200 °C, and particularly preferably a film made of a fluoropolymer. The fluoropolymer and the polyolefin having a melting point of at least 200 °C are each described in detail below.

[0071] The multilayer structural film can, for example, be a film with a first layer that is intended to be in contact with the curable resin at the time of curing, and a further layer. This further layer can be one layer or at least two layers.

[0072] With regard to excellent effects in preventing parting failure and resin burrs, the multilayer structural film is preferably the following mold tool release film (I).

[0073] Mold release film (I): A film comprising a first layer which is intended to be in contact with a curable resin at the time of curing of the curable resin, and a second layer, wherein the first layer has a thickness of 3 to 25 µm and furthermore has a tensile energy storage modulus at 180 °C of 10 to 50 MPa and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and a thickness (µm) of 2000 to 13000.

[0074] In a case where the method for manufacturing a housing for mounting a semiconductor element of the present invention, as described above, is carried out using the mold release film (I), it is preferred that the mold release film (I) is arranged on the upper tool such that the surface of the side of the first layer is directed towards the side of the substrate (side of the mounting surface) in a step in which the convex section of the upper tool is brought into close contact with the mounting surface of the substrate by means of the mold release film.

[0075] In a case where the first layer, which is to be in direct contact with the mounting surface, is a soft layer with a tensile storage modulus at 180 °C that is at most the specified value and has a thickness that is at least the specified value, the first layer will only be slightly compressed even under such low clamping pressure that no dents or damage to the substrate will occur during the pressing of the convex section onto the mounting surface. Furthermore, in a case where the product of the tensile storage modulus at 180 °C and the thickness of the second layer is at most the specified value, the conformability of the mold release film (I) to the upper mold will be sufficient.Therefore, even if the height of the substrate mounting surface or the height of the convex section is uneven, the unevenness is compensated for by the first layer, and thus the convex section of the upper tool is in sufficiently close contact with the entire mold surface of the substrate by means of the mold release film (I). Accordingly, the curable resin hardly tends to penetrate into a space between the convex section and the mounting surface, so that resin ridges do not appear on the entire mounting surface.

[0076] Furthermore, the second layer is preferably a layer having a product of the tensile storage modulus at 180 °C and the thickness that is higher than that of the first layer, and it is a harder layer compared to the first layer. In a case where the first layer has a tensile storage modulus at 180 °C that is at least the specified value and furthermore has a thickness that is at most the specified value, and in a case where the second layer, which is harder than the first layer, is located on the side of the upper tool opposite the first layer, it is less likely that problems will arise such that, when the convex section of the upper tool is pressed onto the mounting surface of the substrate, the first layer may be excessively compressed and protrude into a cavity side, which could lead to parting failure or tearing of the mold parting film (I).

[0077] The tensile strength modulus of the first layer at 180 °C is particularly preferably 10 to 40 MPa. The thickness of the first layer is more preferably 5 to 12 µm, particularly preferably 7 to 12 µm.

[0078] The product of the thermal storage modulus (MPa) at 180 °C and the thickness (µm) of the second layer is particularly preferably from 3000 to 8000.

[0079] The tensile energy storage modulus at 180 °C and the thickness of the second layer can each be optional values ​​and are not specifically limited as long as the product lies within the aforementioned range. In particular, the tensile energy storage modulus at 180 °C is preferably from 90 to 600 MPa, more preferably from 110 to 300 MPa. The thickness is preferably from 6 to 50 µm, more preferably from 12 to 38 µm.

[0080] With regard to the mold release film (I), it is preferred that the thickness of the first layer is 5 to 12 µm and that the product of the tensile storage modulus (MPa) at 180 °C and the thickness (µm) of the second layer is 3000 to 8000. In particular, it is especially preferred that the thickness of the first layer is 7 to 12 µm and that the product of the tensile storage modulus (MPa) at 180 °C and the thickness (µm) of the second layer is 3000 to 8000.

[0081] The tensile storage modulus of each of the first and second layers can be adjusted by the crystallinity of the resin forming each of the first and second layers (hereinafter also referred to as the first-layer resin and the second-layer resin, respectively). Specifically, the tensile storage modulus of the layer made from the resin will be lower if the resin's crystallinity is lower. The resin's crystallinity can be adjusted by a known method. For example, in the case of an ethylene / tetrafluoroethylene copolymer, the crystallinity can be adjusted by the ratio of tetrafluoroethylene- and ethylene-based units, or by the type or proportion of units based on a monomer other than tetrafluoroethylene and ethylene. (Mold tool release film of the first embodiment)

[0082] The Fig.Figure 10 is a schematic cross-sectional view showing the first embodiment of the mold release film (I).

[0083] The mold release film 1 in this embodiment is a mold release film in which the first layer 2 and the second layer 3 are laminated in that order. The mold release film 1 is such that during the curing of the curable resin, the first layer 2 is in contact with a curable resin (i.e., surface 2a is in contact with a curable resin), and the second layer 3 is in contact with the upper part of the mold (i.e., surface 3a is in contact with the upper part of the mold). <Erste Schicht>

[0084] The first layer is a mold release layer for the problem-solving removal of the cured curable resin and the mold release film 1. The areas of the tensile storage module at 180 °C and the thickness of the first layer 2 and preferred areas thereof are each as described above.

[0085] The resin forming the first layer 2 (hereinafter also referred to as a first layer resin) is not limited as long as it has the aforementioned tensile storage modulus, and it may be suitably selected from known thermoplastic resins, rubbers, etc.

[0086] The first layer 2 preferably exhibits a level of separability such that the curable resin (encapsulation body), which is cured in a state where it is in contact with the first layer 2 of the mold release film, can be easily detached from the mold release film 1 during the manufacture of the housing for mounting a semiconductor element. Furthermore, it is preferred that it has heat resistance that withstands the temperature of the mold during molding (typically from 150 to 180 °C). Taking this into account, the resin for the first layer is preferably at least one member selected from the group consisting of a fluoropolymer, a polystyrene, and a polyolefin having a melting point of at least 200 °C. These resins can be used individually, or two or more can be used in combination.

[0087] A fluorinated resin is particularly preferred for the first layer due to its excellent release properties. When the first layer 2 is made of a fluorinated resin, the release of the cured resin product from the mold is excellent. Furthermore, the mold release film 1 exhibits sufficient heat resistance to withstand the temperature of the mold during molding (typically 150 to 180 °C), strength to withstand the pressure or fluidity of the curing resin, and excellent elongation at high temperatures.

[0088] With regard to separability and heat resistance, the fluoropolymer is preferably a fluoroolefin-type polymer. A fluoroolefin-type polymer is a polymer that incorporates units based on a fluoroolefin. The fluoroolefin can be, for example, tetrafluoroethylene, vinyl fluoride, vinylidene fluoride, trifluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, etc. A single type of fluoroolefin can be used, or two or more types can be used in combination.

[0089] The fluoroolefin-type polymer can be, for example, an ethylene / tetrafluoroethylene copolymer (hereinafter also referred to as ETFE), polytetrafluoroethylene, a perfluoro(alkyl vinyl ether) / tetrafluoroethylene copolymer, etc. A single type of fluoroolefin polymer can be used, or two or more types can be used in combination. With regard to separability and heat resistance, the polystyrene is preferably syndiotactic polystyrene. The polystyrene can be extended or contain an additive. A single type of polystyrene can be used, or two or more types can be used in combination.

[0090] The melting point of the polyolefin, which has a melting point of at least 200 °C, is preferably at least 200 °C and at most 300 °C.

[0091] With regard to separability and adaptability to molding tools, the polyolefin, which has a melting point of at least 200 °C, is preferably polymethylpentene. A single type of polyolefin can be used, or two or more types can be used in combination.

[0092] The resin for the first layer is preferably at least one of the above, selected from the group consisting of a fluoroolefin-type polymer and polymethylpentene, more preferably a fluoroolefin-type polymer. Of these, ETFE is particularly preferred with regard to high elongation at high temperature. A single ETFE type can be used, or two or more types can be used in combination.

[0093] ETFE is a copolymer comprising units based on tetrafluoroethylene (hereinafter also referred to as TFE) and units based on ethylene (hereinafter also referred to as E).

[0094] A preferred ETFE is one comprising units based on TFE, units based on E, and units based on a third monomer different from TFE and E. The crystallinity of the ETFE, i.e., the tensile strength storage modulus of the first thermoplastic resin layer 2, can be easily adjusted by the type and content of the units based on the third monomer. Furthermore, the presence of units based on the third monomer (especially a monomer containing fluorine atoms) improves the tensile strength and elongation at high temperatures (especially at approximately 180 °C).

[0095] The third monomer can be a monomer that contains fluorine atoms or a monomer that does not contain a fluorine atom.

[0096] The following monomers (a1) to (a5) can be named as monomers that contain fluorine atoms. Monomer (a1): A fluoroolefin with at most 3 carbon atoms. Monomer (a2): A perfluoroalkylethylene monomer that is linked by X(CF2) n CY=CH2 is represented (where X and Y are each independently a hydrogen atom or a fluorine atom and n is an integer from 2 to 8). Monomer (a3): A fluorovinyl ether. Monomer (a4): A functional group-containing fluorovinyl ether. Monomer (a5): A fluorinated monomer that has an aliphatic ring structure.

[0097] The monomer (a1) can be, for example, a fluoroethylene (such as trifluoroethylene, vinylidene fluoride, vinyl fluoride or chlorotrifluoroethylene) or a fluoropropylene (such as hexafluoropropylene (hereinafter also referred to as HFP) or 2-hydropentafluoropropylene).

[0098] The monomer (a2) is preferably a monomer in which n is from 2 to 6, and particularly preferably a monomer in which n is from 2 to 4. Furthermore, a monomer in which X is a fluorine atom and Y is a hydrogen atom, i.e., a (perfluoroalkyl)ethylene, is particularly preferred.

[0099] The following compounds can be mentioned as specific examples of the monomer (a2). CF3CF2CH=CH2, CF3CF2CF2CF2CH=CH2 ((Perfluorobutyl)ethylene, hereinafter also referred to as PFBE), CF3CF2CF2CF2CF=CH2, CF2HCF2CF2CF=CH2, CF2HCF2CF2CF2CF=CH2, etc.

[0100] The following compounds can be given as specific examples of the monomer (a3). One of the following, which is a diene, is a cyclopolymerizable monomer. CF2=CFOCF3 CF2=CFOCF2CF3, CF2=CF(CF2)2CF3 (Perfluoro(propyl vinyl ether), hereinafter also referred to as PPVE), CF2=CFOCF2CF(CF3)O(CF2)2CF3, CF2=CFO(CF2)3O(CF2)2CF3, CF2=CFO(CF2CF(CF3)O)2(CF2)2CF3, CF2=CFOCF2CF(CF3)O(CF2)2CF3, CF2=CFOCF2CF=CF2, CF2=CFO(CF2)2CF=CF2, etc.

[0101] The following compounds can be mentioned as specific examples of the monomer (a4). CF2=CFO(CF2)3CO2CH3, CF2=CFOCF2CF(CF3)O(CF2)3CO2CH3, CF2=CFOCF2CF(CF3)O(CF2)2SO2F, etc.

[0102] Specific examples of the monomer (a5) include perfluoro(2,2-dimethyl-1,3-dioxol), 2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxol, perfluoro(2-methylene-4-methyl-1,3-dioxolane), etc.

[0103] The following monomers (b1) to (b4) can be named as monomers that do not contain a fluorine atom. Monomer (b1): An olefin. Monomer (b2): A vinyl ester. Monomer (b3): ​​A vinyl ether. Monomer (b4): An unsaturated acid anhydride.

[0104] Specific examples of the monomer (b1) include propylene, isobutene, etc.

[0105] Specific examples of the monomer (b2) include vinyl acetate, etc.

[0106] Specific examples of the monomer (b3) include ethyl vinyl ether, butyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, etc.

[0107] Specific examples of the monomer (b4) include maleic anhydride, itaconic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride ("himic anhydride"), etc.

[0108] The third monomer can be one type alone or two or more types in combination. The third monomer is preferably monomer (a2), HFP, PPVE, or vinyl acetate; more preferably HFP, PPVE, CF3CF2CH=CH2, or PFBE; and particularly preferably PFBE, because this simplifies the adjustment of the crystallinity, i.e., the tensile storage modulus. Furthermore, the presence of units based on a third monomer (especially a monomer containing fluorine atoms) results in excellent tensile strength and elongation at high temperatures (particularly around 180 °C). Therefore, as ETFE, a copolymer comprising units based on TFE, units based on E, and units based on PFBE is particularly preferred.

[0109] In ETFE, the molar ratio (TFE / E) of TFE-based units to E-based units is preferably from 80 / 20 to 40 / 60, more preferably from 70 / 30 to 45 / 55, and particularly preferably from 65 / 35 to 50 / 50. If the TFE / E ratio is within the aforementioned range, the heat resistance and mechanical properties of ETFE will be excellent.

[0110] The proportion of units based on the third monomer in ETFE is preferably from 0.01 to 20 mol%, more preferably from 0.10 to 15 mol%, and particularly preferably from 0.20 to 10 mol%, based on the total (100 mol%) of all units forming ETFE. If the proportion of units based on the third monomer is within the aforementioned range, the heat resistance and mechanical properties of ETFE will be excellent.

[0111] In a case where the units based on the third monomer contain PFBE-based units, the proportion of PFBE-based units is preferably 0.5 to 4.0 mol%, more preferably 0.7 to 3.6 mol%, and particularly preferably 1.0 to 3.6 mol%, based on the total (100 mol%) of all units forming ETFE. If the proportion of PFBE-based units is within the aforementioned range, the tensile strength modulus at 180 °C of the mold release film can be adjusted within the aforementioned range. Furthermore, the tensile strength and elongation at high temperature (especially at about 180 °C) will be improved.

[0112] The flowability (MFR) of ETFE is preferably from 2 to 40 g / 10 min, more preferably from 5 to 30 g / 10 min, and particularly preferably from 10 to 20 g / 10 min. If the MFR of ETFE is within the aforementioned range, the formability of ETFE will be improved and the mechanical properties of the mold release film will be excellent.

[0113] The MFR of ETFE is a value measured at a load of 49 N at 297 °C according to ASTM D3159.

[0114] The first layer (layer 2) can be a layer made solely from the resin used for the first layer, or it can be a layer incorporating an additive, such as an inorganic or organic additive. Inorganic additives include inorganic fillers such as carbon black, silicon dioxide, glass fibers, carbon nanofibers, titanium dioxide, etc. Organic additives include silicone oil, metal soap, etc. <Zweite Schicht>

[0115] A region of the product consisting of the tensile storage modulus (MPa) at 180 °C and the thickness (µm) of the second layer 3 and the preferred region of the product, the tensile storage modulus and the thickness are each as specified above.

[0116] The resin forming the second layer 3 (hereinafter also referred to as the resin for the second layer) can be any one as long as the aforementioned product of the tensile storage modulus and thickness are within the aforementioned ranges, and it can be suitably selected from known thermoplastic resins, rubbers, etc.

[0117] The second layer 3 preferably exhibits a level of separability such that the mold release film 1 can be easily detached from the upper mold during the above-described manufacture of a housing for mounting a semiconductor element. Furthermore, it preferably exhibits heat resistance that is resistant to the temperature of the mold during molding (typically from 150 to 180 °C). Taking this into account, the resin for the second layer is preferably at least one member selected from the group consisting of an unstretched polyamide, a biaxially stretched polyamide, polybutylene terephthalate (hereinafter also referred to as PBT), a polyethylene terephthalate (hereinafter also referred to as PET), and a highly moldable PET.

[0118] Nylon 6 or Nylon MXD6 is preferred as a polyamide with regard to heat resistance, strength and gas barrier properties.

[0119] The highly malleable PET is a PET whose malleability is improved by copolymerizing an additional monomer alongside ethylene glycol and terephthalic acid (or dimethyl phthalate). Specifically, this is PET whose glass transition temperature (Tg), measured using the following method, is at most 105 °C.

[0120] Tg is the temperature at which tan δ (E'' / E'), which is the ratio of the loss elasticity modulus E'' to the storage elasticity modulus E', measured according to ISO 6721-4: 1994 (JIS K7244-4: 1999), reaches its maximum value. Tg is measured by increasing the temperature from 20 °C to 180 °C at a rate of 2 °C / min with a frequency of 10 Hz, a static force of 0.98 N, and a dynamic displacement of 0.035%.

[0121] For the second layer, one type of resin can be used alone, or two or more types can be used in combination.

[0122] The resin for the second layer is preferably PBT or a very malleable PBT.

[0123] The second layer 3 can be a layer made solely from the resin for the second layer, or it can be a layer incorporating an additive, such as an inorganic or organic additive. The inorganic and organic additives can be the same as those described above.

[0124] In the mold release film 1, the first layer 2 and the second layer 3 can be laminated directly or they can be laminated using an adhesive layer, which is not shown in the drawings. <Oberflächenform des Formwerkzeugtrennfilms>

[0125] In the case of the mold release film 1, the surface in contact with the curable resin at the time of curing, i.e., surface 2a on the side of the first layer 2, can be smooth or it can have irregularities that improve release. Furthermore, in the case of the mold release film 1, the surface in contact with the upper tool of the mold at the time of curing of the resin encapsulation section, i.e., surface 3a on the side of the second layer 3, can be smooth or it can have irregularities that improve release.

[0126] The arithmetic mean roughness (Ra) of the surface in the case of a smooth surface is preferably from 0.01 to 0.2 µm, particularly preferably from 0.05 to 0.1 µm. The Ra of the surface in the case where irregularities are present is preferably from 1.5 to 2.1 µm, particularly preferably from 1.6 to 1.9 µm.

[0127] The surface shape, in cases where irregularities are present, can be a shape in which a plurality of convexities and / or concavities are randomly distributed, or it can be a shape in which a plurality of convexities and / or concavities are regularly arranged. Furthermore, the shapes and sizes of the plurality of convexities and / or concavities can be the same or different. The convexities can be elongated ribs extending across the surface of the mold release film, or protrusions or the like distributed across the surface of the mold release film. The concavities can be elongated grooves extending across the surface of the mold release film, or holes or the like distributed across the surface of the mold release film.

[0128] The shape of ribs or grooves can be straight, curved, or bent. Multiple ribs or grooves can be present on the surface of the mold release film, either parallel or in strips. The cross-sectional shape of the ribs or grooves in a direction perpendicular to the longitudinal direction can be polygonal, such as triangular (V-shaped), semicircular, or similar.

[0129] The shape of the protrusions or holes can be polygonal, such as triangular-pyramidal, square-pyramidal or hexagonal-pyramidal, conical, hemispherical, polyhedral, other various irregular shapes, or the like.

[0130] In the case of the mold release film 1, both surface 2a and surface 3a can be smooth, both surface 2a and surface 3a can have irregularities formed on them, or one of surface 2a and surface 3a is smooth and the other has irregularities formed on it. In a case where both surface 2a and surface 3a have irregularities formed on them, the surface roughness (Ra) and / or the surface shapes of the respective surfaces can be the same or different.

[0131] With regard to preventing resin burrs, it is preferred that the surface Ra of surface 2a on the side of the first layer 2 is smaller and it is particularly preferred that surface 2a is smooth.

[0132] With regard to excellent separability of the mold tool release film 1 from the mold tool, it is preferred that irregularities are formed on the surface 3a of the side of the second layer 3. <Dicke des Formwerkzeugtrennfilms>

[0133] The thickness of the mold release film 1 is preferably from 15 to 75 µm, more preferably from 17 to 62 µm, and particularly preferably from 19 to 50 µm. If the thickness is at least the lower limit in the aforementioned range, handling the mold release film 1 is simple, and wrinkling is less likely when the mold release film 1 is positioned to cover the cavity of the upper mold during drawing. If the thickness is at most the upper limit in the aforementioned range, the mold release film 1 can be easily deformed and conforms to the shape of the cavity of the upper mold, thus allowing the mold release film 1 to be in contact with the cavity surface. Accordingly, a high-quality encapsulation body can be stably formed.

[0134] It is preferred that the thickness of the mold release film 1 decreases within the aforementioned range as the cavity of the upper mold becomes large. Furthermore, it is preferred that the thickness decreases within the aforementioned range as the mold is a more complex mold with multiple cavities. <Verfahren zur Herstellung des Formwerkzeugtrennfilms 1>

[0135] The method for producing the mold release film 1 is not specifically limited, and a known method for producing a multilayer film can be used. The following methods (1) and (2) can be cited as specific examples, and they can be selected appropriately taking into account, for example, the materials, thicknesses, etc., of the respective layers. (1) A method of laminating a resin film made from the resin for the first layer and a resin film made from the resin for the second layer. (2) A method of co-extrusion forming of the resin for the first layer and the resin for the second layer.

[0136] Method (1) is preferred as a method for producing the mold release film 1 in view of its excellent manufacturing efficiency.

[0137] In the process (1) various known lamination processes can be used as methods for laminating the respective resin films and, for example, an extrusion lamination process, a dry lamination process, a heat lamination process, etc. can be mentioned.

[0138] In the dry lamination process, the respective resin films are laminated using an adhesive. An adhesive known for dry lamination can be used. For example, a polyvinyl acetate type adhesive, a polyacrylic ester type adhesive made from a homopolymer or copolymer of an acrylic ester (such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, etc.) or a copolymer of an acrylic ester with another monomer (such as methyl methacrylate, acrylonitrile, styrene, etc.), a cyanoacrylate type adhesive, or an ethylene copolymer type adhesive made from, for example, a copolymer of ethylene with another monomer (such as vinyl acetate, ethyl acrylate, acrylic acid, methacrylic acid, etc.) can be used.) is manufactured, a cellulose-type adhesive, a polyester-type adhesive, a polyamide-type adhesive, a polyimide-type adhesive, an amino resin-type adhesive made from a urea resin or a melamine resin, a phenol resin-type adhesive, an epoxy-type adhesive, a polyurethane-type adhesive obtained by crosslinking a polyol (such as a polyether polyol or a polyester polyol) with an isocyanate and / or isocyanurate, a reactive (meth)acrylic adhesive, a rubber-type adhesive made from, for example, chloroprene rubber, nitrile rubber, styrene-butadiene rubber, etc., a silicone-type adhesive, an inorganic adhesive made from an alkali metal silicate, low-melting-point glass, etc., or other adhesives are used.

[0139] The resin films to be laminated by process (1) can be commercially available products or products manufactured using known processes. The resin films can be those that have undergone surface treatment, such as corona treatment, atmospheric pressure plasma treatment, adhesion promoter treatment, etc.

[0140] The manufacturing processes for the resin films are not specifically restricted and known manufacturing processes can be used.

[0141] A method for producing a thermoplastic resin film with smooth surfaces on both sides can be, for example, a melt forming process using an extruder equipped with a T-nozzle with a predetermined lip width.

[0142] A method for producing a thermoplastic resin film having irregularities formed on one or both surfaces may, for example, be a method of transferring irregularities from a base die to the surface of a thermoplastic resin film by thermal processing. With regard to productivity, the following methods (i), (ii), etc., are preferred. In methods (i) and (ii), a cylindrical base die is used, enabling continuous processing, and the productivity of a thermoplastic resin film with formed irregularities is considerably improved. (i) A process in which a thermoplastic resin film is passed between a base die roller and a printing cylinder roller, so that irregularities formed on the surface of the base die roller are continuously transferred to a surface of the thermoplastic resin film. (ii) A method in which a thermoplastic resin extruded from an extruder nozzle is passed between a base die roller and a pressure cylinder roller, so that, simultaneously with the forming of the thermoplastic resin into a film form, irregularities formed on the surface of the base die roller are continuously transferred to a surface of the film-formed thermoplastic resin.

[0143] In methods (i) and (ii), if the printing cylinder roller used is one in which irregularities are formed on its surface, a thermoplastic resin film can be obtained which has irregularities formed on both surfaces. (Mold tool release film in the second embodiment)

[0144] The Fig. Figure 11 is a schematic cross-sectional view showing the second embodiment of the mold release film (I).

[0145] The mold release film 5 in this embodiment is a mold release film in which the first layer 6, the second layer 7, and the third layer 8 are laminated in that order. The mold release film 5 is such that, during the curing of the curable resin, the first layer 6 is in contact with the curable resin and the third layer 8 is in contact with the upper part of the mold.

[0146] The first layer 6 is identical to the first layer 2 in the first embodiment.

[0147] The second layer 7 is identical to the second layer 3 in the first embodiment. <Dritte Schicht>

[0148] The third layer 8 is a layer to prevent waviness of the mold release film 5.

[0149] If, for example, the materials of the first and second layers in the two-layer structure (second layer / first layer), as shown in the first embodiment, are different, the mold release film can become wavy, depending, for example, on the thickness of the second layer or the tensile strength module. If the mold release film becomes wavy, it may not be adsorbed onto the mold at the time of adsorption due to this waviness. The problem of waviness is particularly significant in a case where a short mold release film, pre-cut to the size of the mold, is fed into the mold.If a second layer is used that has such a high tensile storage modulus or such a large thickness as to prevent waviness, the mold adaptability is degraded and therefore it is not suitable for a mold release film that requires mold adaptability.

[0150] If the third layer is arranged on the side of the second layer opposite the first layer, waviness can be suppressed even if a second layer with such a high tensile storage modulus or such a large thickness as to prevent waviness is not used.

[0151] The traction storage modulus at 25 °C of the third layer 8 can be identical or different from that of the first layer 6, however the ratio (traction storage modulus at 25 °C of the third layer 8 / traction storage modulus at 25 °C of the first layer 6) is preferably from 0.5 to 2.

[0152] If the ratio of the train storage modulus at 25 °C is within the aforementioned range, the suppression of ripple will be excellent.

[0153] The thickness of the third layer 8 can be identical to or different from the thickness of the first layer 6, but the difference is preferably at most 5 µm. If the thickness of the third layer 8 is within the aforementioned range, the suppression of waviness is excellent. The thickness of the third layer 8 can, for example, preferably be from 3 to 25 µm, more preferably from 5 to 12 µm, and most preferably from 7 to 12 µm.

[0154] The resin forming the third layer 8 (hereinafter also referred to as a third layer resin) is selected with regard to the separability of the mold release film 1 from the mold, the heat resistance which is resistant to the temperature of the mold during molding (typically from 150 to 180 °C), preferably at least one member which is selected from the group consisting of a fluoropolymer, an acrylic rubber, a thermosetting silicone, a polyester, a polyamide, a polystyrene, an ethylene / vinyl alcohol copolymer and a polyolefin having a melting point of at least 200 °C.

[0155] The fluoropolymer, the polystyrene and the polyolefin, which has a melting point of at least 200 °C, can each be identical to the above.

[0156] With regard to heat resistance or strength, the polyester is preferably PET, a highly malleable PET, PBT or polynaphthalene.

[0157] With regard to heat resistance, strength and gas barrier properties, the polyamide is preferably Nylon 6 or Nylon MXD6.

[0158] These can be used alone, or two or more of them can be used in combination.

[0159] The resin for the third layer is preferably at least one member selected from the group consisting of a fluoropolymer and a polyolefin having a melting point of at least 200 °C.

[0160] The third layer 8 can be a layer made solely of the resin for the third layer, or a layer containing an additive, such as an inorganic additive or an organic additive. The inorganic additive and the organic additive can be defined as those described above.

[0161] In the mold release film 5, the first layer 6 and the second layer 7 can be directly laminated or they can be laminated using an adhesive layer, which is not shown in the drawings. Similarly, the second layer 7 and the third layer 8 can be directly laminated or they can be laminated using an adhesive layer, which is not shown in the drawings. <Oberflächenform des Formwerkzeugtrennfilms>

[0162] In the mold release film 5, the surface in contact with the curable resin during curing, i.e., surface 6a on the side of the first layer 6, can be smooth or it can have irregularities to improve release. Furthermore, in the mold release film 5, the surface in contact with the upper part of the mold during curing, i.e., surface 8a on the side of the third layer 8, can be smooth or it can have irregularities to improve release. In the case where the surface is smooth, the arithmetic mean roughness (Ra) of the surface is preferably from 0.01 to 0.2 µm, and more preferably from 0.05 to 0.1 µm.

[0163] The surface roughness (Ra) of the surface in a case where irregularities are present is preferably from 1.5 to 2.1 µm, and particularly preferably from 1.6 to 1.9 µm. The surface shape in the case where irregularities are present can be a shape in which a plurality of convexities and / or concavities are randomly distributed, or it can be a shape in which a plurality of convexities and / or concavities are regularly arranged. Furthermore, the shape and size of the plurality of convexities and / or concavities can be the same or different. A specific example of a convexity, a concavity, a rib, a protrusion, or a hole can be identical to the foregoing.

[0164] In the case of the mold release film 5, both surface 6a and surface 8a can be smooth, both surface 6a and surface 8a can have irregularities formed on them, or one of surface 6a and surface 8a is smooth and the other has irregularities formed on it. In a case where both surface 6a and surface 8a have irregularities formed on them, the surface area Ra and / or the surface shapes of the respective surfaces can be the same or different.

[0165] With regard to the separability of the mold tool release film 5 from the mold tool, irregularities are preferably formed on the surface 8a of the side of the third layer 8. <Dicke des Formwerkzeugtrennfilms>

[0166] The thickness of the mold release film 5 is preferably from 18 to 100 µm, particularly preferably from 30 to 75 µm. The reason why the lower and upper limits of the aforementioned thickness ranges are preferred is identical to that of the mold release film 1. <Verfahren zur Herstellung des Formwerkzeugtrennfilms 5>

[0167] The method for producing the mold release film 5 is not specifically limited, and a known method for producing a multilayer film is available. For example, the mold release film 5 can be produced in the same way as the mold release film 1, except that the two-layer structure is changed to a three-layer structure.

[0168] The mold release film (I) has been described above with reference to the first and second embodiments; however, the present invention is not limited to the aforementioned embodiments. The respective designs, combinations thereof, etc., in the aforementioned embodiments are exemplary, and additions, omissions, substitutions, and other modifications are possible within a range that does not deviate from the concept of the present invention.

[0169] For example, in the first embodiment, the mold release film 1 can further comprise an additional layer, different from an adhesive layer, which may optionally be provided between the first layer 2 and the second layer 3. Similarly, in the second embodiment, the mold release film 5 can further comprise an additional layer, different from an adhesive layer, which may optionally be provided between the first layer 6 and the second layer 7 or between the second layer 7 and the third layer 8. Such an additional layer could, for example, be a gas barrier layer. The gas barrier layer could, for example, be a metal layer, a vapor-deposited metal layer, or a vapor-deposited metal oxide layer.

[0170] With regard to the effects of the present invention, it is preferred that the mold release film of the present invention has no layers other than the adhesive layer between the first layer, which is to be in contact with the curable resin, and the second layer. That is, it is preferred that the first layer and the second layer are laminated directly or by means of an adhesive layer. EXAMPLES

[0171] The present invention is described in detail below with reference to examples. However, the present invention is not limited by the following description. Of the following Examples 1 to 18, Examples 1 to 16 are examples of the present invention, and Examples 17 and 18 are comparative examples. The materials and evaluation methods used in the examples are shown below. [Materials used] ETFE (1): Copolymer of tetrafluoroethylene / ethylene / PFBE = 52.5 / 46.3 / 1.2 (molar ratio), produced in production example 1 (MFR is 12 g / 10 min). ETFE (2): Copolymer of tetrafluoroethylene / ethylene / PFBE = 56.3 / 40.2 / 3.5 (molar ratio), produced in manufacturing example 2 (MFR is 12.5 g / 10 min). <Herstellungsbeispiel 1: Herstellung von ETFE (1)>

[0172] A polymerization tank with an internal volume of 1.3 liters, equipped with a stirrer, was purged of air, 881.9 g of 1-hydrotridecafluorohexane, 335.5 g of 1,3-dichloro-1,1,2,2,3-pentafluoropropane (trade name "AK225cb", manufactured by Asahi Glass Company, Limited, hereinafter referred to as AK225cb) and 7.0 g of CH2=CHCF2CF2CF2CF3 (PFBE) were introduced, 165.2 g of TFE and 9.8 g of ethylene (hereinafter referred to as E) were injected, the temperature in the polymerization tank was raised to 66 °C and 7.7 ml of an AK225cb solution containing 1 wt% tert-butyl peroxypivalate (hereinafter referred to as PBPV) was introduced as a polymerization initiator solution.

[0173] A monomer mixture gas consisting of TFE / E = 54 / 46, based on the molar ratio, was continuously introduced so that the pressure remained constant during polymerization. Furthermore, PFBE was continuously introduced concurrently with the monomer mixture gas in an amount corresponding to 1.4 mol% of the total molar number of TFE and E. 2.9 hours after the initiation of polymerization, at the time when 100 g of the monomer mixture gas had been introduced, the internal temperature of the polymerization tank was reduced to room temperature, and simultaneously the pressure of the polymerization tank was lowered to atmospheric pressure.

[0174] The resulting slurry was then filtered through a glass filter and the solids content was collected and dried at 150 °C for 15 hours, yielding 105 g ETFE (1). <Herstellungsbeispiel 2: Herstellung von ETFE (2)>

[0175] 90 g of ETFE (2) were obtained in the same manner as in Preparation Example 1, except that the internal volume of the polymerization tank was 1.2 liters, the amounts of 1-hydrotridecafluorohexane, PFBE, AK225cb, TFE, E, and AK225cb solution containing 1 wt% PBPV, introduced prior to initiating polymerization, were changed in this order from 881.9 g to 0 g, from 335.5 g to 291.6 g, from 7.0 g to 16.0 g, from 165.2 g to 186.6 g, from 9.8 g to 6.4 g, and from 5.8 ml to 5.3 ml, and the molar ratio of TFE / E of the monomer mixture gas and the amount of PFBE continuously introduced during polymerization were changed. were added, in this order each time from 54 / 46 to 58 / 42 and from 3.6 mol% to 0.8 mol% (relative to the total number of moles of TFE and E), and after 3 hours starting from the initiation of the polymerization at the time,when 90 g of the monomer mixture gas have been introduced and the internal temperature of the polymerization tank has been lowered to room temperature. <Thermoplastischer Harzfilm>

[0176] ETFE film (1-1): The thickness is 16 µm, one side exhibits irregularities, where Ra on one side is 0.5 and Ra on the opposite side is 0.1. The ETFE film (1-1) was produced by the following process.

[0177] ETFE (1) was extruded at 320 °C through an extruder in which the lip opening was set to produce a film thickness of 16 µm. The base die roller, film forming speed, and squeeze pressure were adjusted to produce an ETFE film.

[0178] ETFE film (1-2): The thickness was 12 µm. Both surfaces were smooth and the Ra of each surface was 0.1. The ETFE film (1-2) was produced in the same way as the ETFE film (1-1), except that the respective conditions were adjusted.

[0179] ETFE film (1-3): The thickness was 25 µm. Both surfaces were smooth and the Ra of each surface was 0.1. The ETFE film (1-3) was produced in the same way as the ETFE film (1-1), except that the respective conditions were adjusted.

[0180] ETFE film (1-4): The thickness was 50 µm. Both surfaces were smooth and the Ra of each surface was 0.1. The ETFE film (1-4) was produced in the same way as the ETFE film (1-1), except that the respective conditions were adjusted.

[0181] ETFE film (1-5): The thickness was 3 µm. Both surfaces were smooth and the Ra of each surface was 0.1. The ETFE film (1-5) was produced in the same way as the ETFE film (1-1), except that the respective conditions were adjusted and, furthermore, the molten ETFE (1), extruded from a T-nozzle, was in contact with a PET film on a base die roller and was wound up together with the PET film, so that film formation was carried out.

[0182] ETFE film (2-1): The thickness was 12 µm. Both surfaces were smooth and the Ra of each surface was 0.1. The ETFE film (2-1) was produced in the same way as the ETFE film (1-1), except that ETFE (2) was used instead of ETFE (1) and the respective conditions were adjusted.

[0183] PET film (1): The thickness was 12 µm. “Teijin Tetoron NS” (manufactured by Teijin DuPont Films Japan Limited) with a thickness of 12 µm was used. Glass transition temperature: 118 °C. Both surfaces were smooth and the Ra of each surface was 0.2.

[0184] PET film (2): The thickness was 16 µm. “DIAFOIL H500” (manufactured by Mitsubishi Plastics, Inc.) with a thickness of 16 µm was used. Glass transition temperature: 118 °C. Both surfaces were smooth and the Ra of each surface was 0.2.

[0185] PET film (3): The thickness was 25 µm. “DIAFOIL H500” (manufactured by Mitsubishi Plastics, Inc.) with a thickness of 25 µm was used. Glass transition temperature: 118 °C. Both surfaces were smooth and the Ra of each surface was 0.2.

[0186] A highly formable PET film was used: the thickness was 25 µm. “TEFLEX FT3PE”, manufactured by Teijin DuPont Films Japan Limited, was used. Glass transition temperature: 86 °C. Both surfaces were smooth, and the Ra of each surface was 0.2.

[0187] Unstretched nylon film: The thickness was 20 µm. “DIAMIRON CZ” (manufactured by Mitsubishi Plastics, Inc.) was used. Both surfaces were smooth and the Ra of each surface was 0.1.

[0188] Biaxially stretched nylon film: The thickness was 12 µm. “HARDEN N1100” (manufactured by Toyobo Co., Ltd.) was used. Both surfaces were smooth and the Ra of each surface was 0.2.

[0189] PTFE film: The thickness was 50 µm. “NITOFLON PTFE 900UL” (manufactured by Nitto Denko Corporation) was used. Both surfaces were smooth and the Ra of each surface was 0.2.

[0190] Polymethylpentene film: The thickness was 12 µm. Both surfaces were smooth and the Ra of each surface was 0.1. The polymethylpentene film was produced by the following procedure.

[0191] The polymethylpentene resin “TPX MX004” (manufactured by Mitsui Chemicals, Inc.) was extruded at 280 °C through an extruder with the lip opening set to achieve a thickness of 12 µm. A polymethylpentene film was obtained by adjusting the base die roller, film formation speed, and squeeze pressure.

[0192] PBT film (1): The thickness was 38 µm. Ra of one surface was 1.2 and Ra of the other surface was 0.1. “NOVADURAN 5020” (manufactured by Mitsubishi Engineering-Plastics Corporation) was melt extruded at 280 °C through an extruder with a T-nozzle, the lip opening degree of which was set to achieve a thickness of 38 µm, and the PBT film (1) was produced by adjusting the base die roller, the film forming speed and the squeeze pressure.

[0193] PBT film (2): The thickness was 38 µm. Ra of one surface was 1.2 and Ra of the other surface was 0.1. “NOVADURAN 5505S” (manufactured by Mitsubishi Engineering-Plastics Corporation) was melt extruded at 280 °C through an extruder with a T-nozzle, the lip opening degree of which was set to achieve a thickness of 38 µm, and the PBT film (2) was produced by adjusting the base die roller, the film forming speed and the squeeze pressure.

[0194] For each film, a surface with a low Ra was used as the adhesive surface during dry lamination. Furthermore, in one case where the wet stress of the adhesive surface during dry lamination of each film was lower than 40 mN / m according to ISO 8296:1987 (JIS K6768:1999), the surface was subjected to corona treatment to raise the wet stress to at least 40 mN / m. <haftmittelschicht>

[0195] The following urethane-type adhesive A was used as the adhesive to be used in a dry lamination step for bonding the respective films. [Urethane-type adhesive A] Main agent: CRISVON NT-258 (manufactured by DIC Corporation) Curing agent: Coronate 2096 (manufactured by Nippon Polyurethane Industry Co., Ltd.)

[0196] The main agent and the hardening agent were mixed such that the mass ratio based on the solids content (main agent:hardening agent) is 10:1, and ethyl acetate was used as a diluent. [Evaluation procedure] <dicke>

[0197] Using a DG-525H contact thickness gauge (manufactured by Ono Sokki Co., Ltd.) with AA-026 probe (ϕ 10 mm SR7), the thickness of a film was measured at 10 points, ensuring equal spacing in the transverse direction, and the average value was used as the thickness. <Zugspeichermodul bei 180 °C>

[0198] Using a SOLID L-1 dynamic viscoelasticity measuring device (manufactured by Toyo Seiki Co., Ltd.), the storage elasticity modulus E' was measured according to ISO 6721-4: 1944 (JIS K7244-4: 1999). The sample measured was 8 mm wide × 20 mm long, and E', determined by increasing the temperature from 20 °C to 180 °C at a rate of 2 °C / min at a frequency of 10 Hz with a static force of 0.98 N and a dynamic displacement of 0.035% at 180 °C, was used as the tensile storage modulus at 180 °C. <Beschädigung oder Delle im Anschlussrahmen>

[0199] It was visually confirmed whether the enclosure mounting frame manufactured in each example had any dents or damage to a section in contact with a protrusion, with an assessment carried out according to the following standards. ◯ (Good): No damage or dent was found. × (Bad): Damage or dents were found. <harzgrate>

[0200] In each example, a section of the housing's connection frame (the contacted section) that was in contact with a protrusion was examined using a digital optical microscope. The contacted section was photographed, and the resulting photograph was divided by a grid. The percentage of resin burrs present was then determined from the number of grid cells where burrs were detected. The results were evaluated against the following standards. ◯ (Good): At most 10%. Δ (Not bad): At most 30% and more than 10%. × (Bad): More than 30%. <Eindringen des Formwerkzeugtrennfilms>

[0201] The encapsulation body of the housing, which was manufactured in each example, was visually confirmed to see if any trace of the mold release film penetration was detected, and an evaluation was carried out according to the following standards. ◯ (Good): No penetration of the mold release film was detected. Δ (Not bad): Partial penetration of the mold release film was detected and a dent was found in the interface between the connecting frame and the encapsulation body. × (Bad): The mold release film had completely penetrated the encapsulation body and was not separated. [Example 1](Production of a mold release film)

[0202] On the surface where Ra of the PBT film (1) was 0.1, the adhesive of urethane type A was applied in an amount of 0.5 g / m² 2 The coating was applied by engraving and a corona-treated surface of the ETFE film (1-2) was bonded by dry lamination to form a mold release film. The dry lamination conditions were set to a substrate width of 1000 mm, a transport speed of 20 m / min, a drying temperature of 80 to 100 °C, a laminate roller temperature of 25 °C, and a roller pressure of 3.5 MPa. (Manufacturing a housing by injection molding)

[0203] An upper mold with 500 convex sections, each with a round shape of Φ 5 mm, and a lower mold equipped with a connecting frame were heated to 180 °C. A mold release film was applied to the upper mold, and the air between the upper mold and the mold release film was then removed by vacuum pumping, causing the mold release film to adhere to the upper mold. The lower mold was then moved and clamped until the convex section of the upper mold, via the mold release film, made contact with the section to be exposed by the connecting frame. Resin was then injected, filling the space between the upper and lower molds. The resin was then cured to form an encapsulation body, resulting in a housing comprised of the connecting frame and the encapsulation body.This housing featured 500 concave sections with a round shape of Φ 5 mm, and part of the connecting frame was exposed on the lower surface of the concave sections. Furthermore, the resin injection pressure was the minimum injection pressure required to transfer the shape of the hollow housing into each mold release film, and the clamping pressure was the minimum pressure required to reduce resin flash. The resin used was SUMIKON EME G770H type F ver. GR (manufactured by Sumitomo Bakelite Co., Ltd.). [Examples 2 to 6 and 8]

[0204] A mold release film was obtained in the same way as in Example 1, except that a material was selected such that a film structure as shown in Table 1 was obtained.

[0205] A housing was manufactured in the same way as in Example 1 using the obtained mold release film. [Example 7]

[0206] On the surface where Ra of the PBT film (1) was 0.1, the urethane-type adhesive A was applied in an amount of 0.5 g / m². 2 The coating was applied by engraving and a corona-treated surface of the ETFE film (1-5) was laminated onto the PET film (1-1) and glued to it, and then the PET film (1-1) was removed, so that the mold release film was obtained.

[0207] A housing was manufactured in the same way as in Example 1 using the obtained mold release film. [Example 9]

[0208] On one side of the PET film (1) the adhesive A of the urethane type was applied in an amount of 0.5 g / m² 2 The PET film (1-2) was applied by engraving and a corona-treated surface of the ETFE film was bonded to it. Furthermore, the ETFE film (1-2) was bonded to the opposite surface of the PET film (1-1) in the same manner, thus obtaining a mold release film.

[0209] A housing was manufactured in the same way as in Example 1 using the obtained mold release film. [Examples 10 to 14]

[0210] A mold release film was obtained in the same way as in Example 9, except that the material was selected to obtain the film structure shown in Table 2.

[0211] A housing was manufactured in the same way as in Example 1 using the obtained mold release film. [Example 15]

[0212] The ETFE film (1-4) was used as a mold release film.

[0213] A housing was manufactured in the same way as in Example 1 using the obtained mold release film. [Example 16]

[0214] The ETFE film (1) was used as a mold release film.

[0215] A housing was manufactured in the same way as in Example 1 using the obtained mold release film. [Example 17]

[0216] A housing was manufactured in the same way as in Example 1 without the use of a mold release film. [Example 18]

[0217] A PTFE film with a flat shape and a thickness equal to the height of the lower surface section of the housing is processed, for example, by etching, so that the convex section remains in the position corresponding to the lower surface section of the housing, thus obtaining a mold release film (mold release film with a formed convex section).

[0218] Using an upper tool that does not have a convex section, a housing is produced in the same way as in Example 1, wherein a convex section of the obtained mold tool release film is in contact with a connecting frame.

[0219] The film structure of the mold release film, the product of the thickness (µm) and the tensile storage modulus at 180 °C of the second layer (MPa) (180 °C tensile storage modulus × thickness), the tensile storage modulus at 180 °C of the first layer and the third layer, and the evaluation results (damage / dent of the connecting frame, resin burrs, penetration of the mold release film) in examples 1 to 16 and 18 are shown in Tables 1 to 3. TABLE 1 Example. 1 2 3 4 5 6 7 8 Film structure Second shift PBT film (1) Very malleable PET film PBT film (1) PBT film (1) PBT film (2) PBT film (1) PBT film (1) PBT film (1) Adhesive layer Composition for forming an adhesive layer Adesurethane type adhesive Ades urethane-type adhesive Ades urethane-type adhesive Ades urethane-type adhesive Ades urethane-type adhesive Ades urethane-type adhesive Adesurethane type adhesive Adesurethane type adhesive First shift ETFE film (1-2) ETFE film (1-2) ETFE film (1-1) ETFE film (2-1) ETFE film (1-2) Polymethyl pentane film ETFE film (1-5) ETFE film (1-3) 180°C traction energy storage module × thickness of the second layer (MPa · µm) 4560 3500 4560 4560 2660 4560 4560 4560 180°C first layer traction energy storage module (MPa) 40 40 40 10 40 30 40 40 Damage or dent to a connector frame ◯ ◯ ◯ ◯ ◯ ◯ ◯ ◯ Harzgrate ◯ ◯ ◯ ◯ ◯ ◯ △ ◯ Penetration of the molding tool film ◯ ◯ ◯ ◯ △ ◯ ◯ △ TABLE 2 Example. 9 10 11 12 13 14 Film structure Third layer ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) Adhesive layer Composition for forming an adhesive layer Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A Second shift PET film (1) PET film (2) PET film (3) Highly malleable PET film Unstretched nylon film Biaxially stretched nylon film Adhesive layer Composition for forming an adhesive layer Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A Urethane-type adhesive A First shift ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) ETFE film (1-2) 180°C traction storage module × thickness of the second layer (MPa · µm) 6000 8000 12500 2250 5600 7200 180°C first layer traction energy storage module (MPa) 40 40 40 40 40 40 180°C third layer traction energy storage module (MPa) 40 40 40 40 40 40 Damage or dent to a connector frame ◯ ◯ ◯ ◯ ◯ ◯ Harzgrate ◯ ◯ △ ◯ ◯ ◯ Penetration of the molding tool film ◯ ◯ ◯ △ ◯ ◯ TABLE 3 Example. 15 16 17 18 film ETFE film (1-4) PTFE film No mold release film Mold release film with formed convex section Damage or dent to a connector frame ◯ ◯ × ◯ Harzgrate ◯ △ × ◯ Penetration of the molding tool film Δ ◯ ◯ ×

[0220] As shown in the preceding results, no damage or dents to the connection frame were observed in Examples 1 to 16, and resin burrs were adequately prevented. Furthermore, penetration of the mold release film from the encapsulation body was prevented. On the other hand, in Example 17, where the convex section of the upper tool was in direct contact with the connection frame without the use of a mold release film, damage or dents to the connection frame of the resulting housing were observed, and numerous resin burrs were also found.

[0221] In Example 18, where a mold release film was used in which a convex section was integrated, the mold release film, according to the assessment of the penetration of a mold release film, has completely penetrated an encapsulation body and therefore the housing cannot be separated.

[0222] In examples 1 to 16, the penetration of a mold release film was found to be slight in examples 5, 8, 12 and 15, but no penetration of a mold release film was found in examples 1 to 4, 6, 7, 9 to 11, 13, 14 and 16, which is preferred.

[0223] It is assumed that the reason why the results of examples 1 to 4, 6, 7, 9 to 11, 13, 14 and 16 are better than the results of examples 5 and 12 is that the mold release film is relatively hard and is hardly compressed during clamping, since the 180 °C tensile storage modulus × thickness of the second layer is large compared to examples 5 and 12.

[0224] It is assumed that the reason why the results of examples 1 to 4, 6, 7, 9 to 11, 13, 14 and 16 are better than the result of example 8 is that the change in thickness is relatively small when the first layer is compressed during clamping, since the thickness of the first layer is small compared to example 8.

[0225] It is assumed that the reason why the results of examples 1 to 4, 6, 7, 9 to 11, 13, 14 and 16 are better than the result of example 15 is that the mold release film, which has the second layer, is hardly compressed during clamping, since such a mold release film is harder than that of example 15, where the mold release film only has the first layer (a single-layer ETFE film), and that the change in thickness is relatively small when the mold film is compressed, since the thickness of the first layer is small compared to example 15.

[0226] In examples 1 to 16, the occurrence of resin ridges is at most 30% and more than 10% in examples 7, 11 and 16, however, on the other hand, the occurrence of resin ridges was at most 10% in examples 1 to 6, 8 to 10 and 12 to 15.

[0227] It is assumed that the reason why the results of examples 1 to 6, 8 to 10 and 12 to 15 are better than the result of example 7 is that the mold release film tends to be slightly compressed during clamping, as the thickness of the first layer is large compared to example 7.

[0228] It is assumed that the reason why the results of Ex. 1 to 6, 8 to 10 and 12 to 15 are better than the result of Ex. 11 is that the mold release film is relatively soft and tends to be slightly compressed during clamping, since the second layer has a 180 °C tensile storage modulus × thickness that is small compared to Ex. 11.

[0229] It is assumed that the reason why the results of examples 1 to 6, 8 to 10 and 12 to 15 are better than the result of example 16 is that the mold release film tends to be slightly compressed during clamping, and the adhesion between the mold release film and the contact section tends to be high, since its first layer, which is in contact with the contact section, is soft compared to the PTFE film.

[0230] Based on the above results, it could be confirmed that the aforementioned mold release film used for the manufacture of a housing is preferably a mold release film comprising a first layer with a tensile storage modulus at 180 °C of 10 to 50 MPa and a thickness of 5 to 12 µm and a second layer with a product of the tensile storage modulus (MPa) at 180 °C and the thickness (µm) of 3000 to 8000, as used in Examples 1 to 4, 6, 9, 10, 13 and 14. COMMERCIAL APPLICABILITY

[0231] The method for manufacturing a housing for mounting a semiconductor element of the present invention is used in various fields of a method for manufacturing a housing for mounting a semiconductor element, such as a solid-state imaging element or MEMS, in particular as a method for manufacturing a housing with a hollow structure for mounting a semiconductor element. REFERENCE MARK

[0232] 1: Mold release film, 2: First layer, 2a: Surface, 3: Second layer, 3a: Surface, 5: Mold release film, 6: First layer, 6a: Surface, 7: Second layer, 8: Third layer, 8a: Surface, 10: Substrate, 10a: Mounting surface, 10A: Substrate, 12: Encapsulation body, 12A: Cured product, 14: Concave section, 16: Substrate, 16a: Inner connection, 16b: Outer connection, 16c: Chip contact point, 18: Encapsulation body, 18a: Frame-shaped section, 18b: Lower section, 19: Cured product, 20: Concave section, 30: Mold release film, 40: Curable resin, 50: Upper tool, 52: Lower tool, 54: Cavity 56: Convex section, 58: Substrate arrangement section, 60: Resin injection section, 62: Resin arrangement section, 64: Piston, 110: Housing for mounting a semiconductor element, 120: Housing for mounting a semiconductor element, 200: Convex section, 202: Upper tool, 204: Lower tool, 206: Connection frame, 208: Resin,210: Mold release film, 212: Convex section, 214: Wall,< / harzgrate> < / dicke> < / haftmittelschicht>

Claims

A method for manufacturing a housing for mounting a semiconductor device by using a mold tool comprising an upper tool and a lower tool, wherein the housing for mounting a semiconductor device comprises a substrate having a mounting surface for mounting a semiconductor device and an encapsulation body formed from a cured product of a curable resin and having a frame-shaped section surrounding the mounting surface, and wherein the housing has a concave section formed by the mounting surface and the encapsulation body, and wherein the method for manufacturing a housing for mounting a semiconductor device comprises: a step of arranging a mold tool release film having a substantially constant thickness over the film on the upper tool, which has a convex section whose shape corresponds to the concave section,of arranging the substrate on the lower tool and closing the upper and lower tools so that the convex section is in close contact with the mounting section of the substrate by means of the mold release film; a step of filling a space formed between the upper and lower tools with a curable resin, whereupon the curable resin is cured; and a step of separating a cured product of the curable resin together with the substrate from the mold, wherein the mold release film has a first layer which is to be in contact with the curable resin at the time of curing of the curable resin, and a second layer.the first layer has a thickness of 3 to 25 µm and furthermore has a tensile energy storage modulus at 180 °C of 10 to 40 MPa, and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and the thickness (µm) of 2000 to 13000. Method for manufacturing a housing for mounting a semiconductor element according to claim 1, wherein the first layer has a thickness of 5 to 12 µm and the second layer has a product of the tensile energy storage module (MPa) at 180 °C and a thickness (µm) of 3000 to 8000. Method for manufacturing a housing for mounting a semiconductor element according to claim 1 or 2, wherein the mold tool release film further comprises a third layer which is to be in contact with the mold tool at the time of curing of the curable resin, and the third layer has a thickness of 3 to 25 µm and further comprises a ratio of the tensile storage modulus at 25 °C to the tensile storage modulus at 25 °C of the first layer (i.e., tensile storage modulus at 25 °C of the third layer / tensile storage modulus at 25 °C of the first layer) of 0.5 to 2. Mold release film for use in the method for manufacturing a housing for mounting a semiconductor element as defined in claim 1, wherein the mold release film comprises a first layer which is to be in contact with the curable resin at the time of curing of the curable resin, and a second layer, wherein the first layer has a thickness of 3 to 12 µm and further comprises a tensile storage modulus at 180 °C of 10 to 40 MPa, and the second layer comprises a product of the tensile storage modulus (MPa) at 180 °C and the thickness (µm) of 2000 to 13000. Molding tool release film according to claim 4, wherein the first layer has a thickness of 5 to 12 µm and the second layer has a product of the tensile energy storage modulus (MPa) at 180 °C and the thickness (µm) of 3000 to 8000. Mold tool release film according to claim 4 or 5, further comprising a third layer which is to be in contact with the mold tool at the time of curing of the curable resin, wherein the third layer has a thickness of 3 to 25 µm and further comprising a ratio of the tensile storage modulus at 25 °C to the tensile storage modulus at 25 °C of the first layer (i.e., tensile storage modulus at 25 °C of the third layer / tensile storage modulus at 25 °C of the first layer) of 0.5 to 2. Mold release film according to one of claims 4 to 6, wherein a resin forming the first layer is at least one member selected from the group consisting of a fluoropolymer, a polystyrene and a polyolefin having a melting point of at least 200 °C. Mold release film according to one of claims 4 to 7, wherein a resin forming the second layer is at least one member selected from the group consisting of an unstretched polyamide, a biaxially stretched polyamide, a polybutylene terephthalate, a polyethylene terephthalate and a highly moldable polyethylene terephthalate. Mold release film according to one of claims 4 to 8, wherein a resin forming the third layer is at least one member selected from the group consisting of a fluoropolymer, an acrylic rubber, a thermosetting silicone, a polyester, a polyamide, a polystyrene, an ethylene / vinyl alcohol copolymer and a polyolefin having a melting point of at least 200 °C.

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