Protective cover material and material supply sheet

Abstract

The protective cover member provided by the present invention is arranged on a surface of an object that has an opening, the surface being provided to the object, wherein the member is configured from a laminate including a protective film that has such a shape as to cover the opening when the member is arranged on the surface, and an adhesive agent layer. The adhesive agent layer is provided with a cured adhesive layer of a silicone adhesive agent composition containing an addition-reaction-cured silicone adhesive agent. In the protective cover member, deformation and separation from an arrangement surface are suppressed even during solder reflow or in other high-temperature situations.

Description

[Technical Field]

[0001] The present invention relates to a protective cover member to be placed on a surface of an object having an opening, and a member supplying tape for supplying the member. [Background technology]

[0002] Protective cover members are known that are placed on a surface of an object having an opening to prevent foreign matter from entering the opening. Protective cover members typically include a protective film that prevents foreign matter from entering the opening when the member is placed on the surface, and an adhesive layer that secures the member to the surface. Patent Document 1 discloses a member that includes a porous film primarily composed of polytetrafluoroethylene (hereinafter referred to as "PTFE") that allows gas and / or sound to pass through while preventing the passage of foreign matter such as water droplets, and a heat-resistant double-sided adhesive sheet that is placed in a limited area on at least one main surface of the porous film to secure the porous film to another component. Patent Document 1 attempts to ensure the heat resistance of the component against high temperatures during solder reflow by focusing on the substrate of the double-sided adhesive sheet that secures the component to the surface of the circuit board, which is the target object. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-81881 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, there has been a demand for protective cover members to be placed over openings in microscopic products such as microelectromechanical systems (MEMS). There is also a demand for protective cover members to be placed not only on the exterior surface but also on the interior surface of the product, leading to a trend toward smaller protective film areas. Under these circumstances, in order to maximize breathability and / or sound permeability through the protective film, it is necessary to reduce the area of ​​the adhesive layer that hinders breathability and sound permeability, for example, by narrowing the width of the adhesive layer placed around the periphery of the protective film. According to the inventors' investigations, reducing the area of ​​the adhesive layer tends to cause deformation of the protective cover member or peeling from the surface (the placement surface) under high temperatures such as solder reflow. Patent Document 1 does not take this situation into consideration.

[0005] An object of the present invention is to provide a protective cover member that is suppressed from deforming or peeling off from the mounting surface even under high temperatures such as solder reflow. [Means for solving the problem]

[0006] The present invention provides A protective cover member to be placed on a surface of an object having an opening, the member is composed of a laminate including a protective film having a shape that covers the opening when the member is placed on the surface, and a pressure-sensitive adhesive layer; a protective cover member, wherein the pressure-sensitive adhesive layer comprises a cured pressure-sensitive adhesive layer of a silicone pressure-sensitive adhesive composition including an addition reaction curing type silicone pressure-sensitive adhesive; to provide.

[0007] From another aspect, the present invention provides a method for manufacturing a semiconductor device comprising: A base sheet and one or more protective cover members disposed on the base sheet, The protective cover member is a member supply sheet which is the protective cover member of the present invention; to provide. [Effects of the Invention]

[0008] According to the inventors' investigations, one of the causes of the deformation and peeling is shrinkage of the adhesive layer at high temperatures. In the protective cover member of the present invention, the adhesive layer comprises a specific silicone-based cured adhesive layer. This adhesive layer shrinks little at high temperatures. Therefore, the deformation and peeling at high temperatures can be suppressed. [Brief explanation of the drawings]

[0009] [Figure 1A] FIG. 1A is a cross-sectional view schematically showing an example of a protective cover member of the present invention. [Figure 1B] FIG. 1B is a plan view of the protective cover member 1 of FIG. 1A viewed from the pressure-sensitive adhesive layer 3 side. [Figure 2] FIG. 2 is a schematic diagram showing an example of how the protective cover member of the present invention is disposed on an object. [Figure 3] FIG. 3 is a cross-sectional view schematically showing an example of the protective cover member of the present invention. [Figure 4A] FIG. 4A is a cross-sectional view schematically showing an example of the protective cover member of the present invention. [Figure 4B] FIG. 4B is a cross-sectional view schematically showing an example of the protective cover member of the present invention. [Figure 5] FIG. 5 is a cross-sectional view schematically showing an example of the protective cover member of the present invention. [Figure 6] FIG. 6 is a cross-sectional view schematically showing an example of the protective cover member of the present invention. [Figure 7] FIG. 7 is a plan view schematically showing an example of a member supplying sheet of the present invention. [Figure 8] FIG. 8 is a diagram showing the appearance of each example and comparative example sample after heat treatment. DETAILED DESCRIPTION OF THE INVENTION

[0010] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the accompanying drawings, but is not limited to the following embodiments.

[0011] [Protective cover material] An example of a protective cover member of the present invention is shown in FIGS. 1A and 1B. FIG. 1B is a plan view of the protective cover member 1 of FIG. 1A, viewed from the side of the adhesive layer 3. FIG. 1A shows cross section AA of FIG. 1B. The protective cover member 1 is a member to be placed on a surface (placement surface) of an object having an opening. Placing the protective cover member 1 on the placement surface can, for example, prevent the intrusion of foreign matter into and / or through the opening, in other words, the intrusion of foreign matter through the opening. The protective cover member 1 may be a member to be placed on the surface of an object having an opening to prevent the intrusion of foreign matter into the opening. The protective cover member 1 is composed of a laminate 4 including a protective film 2 and an adhesive layer 3. The protective film 2 has a shape that covers the opening when the protective cover member 1 is placed on the surface. The adhesive layer 3 is located on one main surface of the protective film 2. The adhesive layer 3 is bonded to the protective film 2. The protective cover member 1 can be fixed to the placement surface of the object by the adhesive layer 3.

[0012] The adhesive layer 3 includes a cured adhesive layer 11 of a silicone adhesive composition A (hereinafter referred to as "composition A") containing an addition reaction curing type silicone adhesive. The cured adhesive layer 11 is a cured layer of composition A and has adhesive properties. The cured adhesive layer 11 is formed by curing composition A. The adhesive layer 3 in FIGS. 1A and 1B is made of a cured adhesive layer 11. The cured adhesive layer 11 is in contact with the protective film 2. The cured adhesive layer 11 can also serve as the bonding surface 12 of the protective cover member 1 with respect to the placement surface of the object. The cured adhesive layer 11 and the adhesive layer 3 including the cured adhesive layer 11 shrink little at high temperatures. This can prevent deformation of the protective film 2 due to shrinkage and peeling of the adhesive layer 3 from the protective film 2 and / or the placement surface.

[0013] Composition A contains an addition reaction curable silicone adhesive, and preferably contains an addition reaction curable silicone adhesive as a main component. In this specification, "main component" refers to the component with the largest content. The content of the main component is, for example, 50% by weight or more, and may be 60% by weight or more, 70% by weight or more, 80% by weight or more, 90% by weight or more, 95% by weight or more, or even 99% by weight or more. Composition A may be composed of an addition reaction curable silicone adhesive. Composition A preferably does not contain a peroxide curable silicone adhesive. A cured adhesive layer of a peroxide curable silicone adhesive exhibits significant shrinkage at high temperatures.

[0014] The difference in shrinkage rate at high temperatures between a cured adhesive layer of an addition reaction-curable silicone adhesive and a cured adhesive layer of a peroxide-curable silicone adhesive is presumably due to the difference in the distribution of crosslinking points resulting from the difference in reaction mechanism. In the addition reaction-curable type, the addition reaction groups that serve as crosslinking points are uniformly present throughout the composition, and three-dimensional crosslinking occurs due to the hydrosilane compound, which has many crosslinking points, resulting in a relatively uniform distribution of crosslinking points in the cured adhesive layer. On the other hand, in the peroxide-curable type, a reaction occurs in which functional groups generated by radicals from among the multiple functional groups that silicone molecules may possess become crosslinking points in a random and competitive manner, resulting in different positions and numbers of crosslinking points depending on the silicone molecule, resulting in a more random distribution of crosslinking points in the cured adhesive layer. This difference is presumably responsible for the difference in shrinkage rate at high temperatures.

[0015] Composition A usually contains a silicone compound having an addition reactive group (component A), a silicone resin (component B), a hydrosilane compound (component C), and a catalyst (component D).

[0016] Examples of silicone compounds (component A) having addition reactive groups include organopolysiloxanes having addition reactive groups and partial condensates thereof. The organopolysiloxane may be any of monoorganopolysiloxanes, diorganopolysiloxanes, and triorganopolysiloxanes, preferably at least one selected from monoorganopolysiloxanes and diorganopolysiloxanes, and more preferably diorganopolysiloxanes. Examples of organo groups in organopolysiloxanes are hydrocarbon groups having 1 to 8 carbon atoms, preferably hydrocarbon groups having 1 to 4 carbon atoms, and more preferably alkyl groups having 1 to 4 carbon atoms (which may be linear or branched). A typical example of the organo group is a methyl group. Some of the organo groups may be substituted with hydroxyl groups. Examples of addition reactive groups are monovalent organic groups containing alkenyl groups, typical examples being vinyl groups and allyl groups, with vinyl groups being preferred. The addition reactive group is usually present at at least one end of the molecule of component A, and may be present at both ends. Specific examples of component A include vinyldimethylpolysiloxane, vinyldiethylpolysiloxane, vinylisopropylpolysiloxane, and vinylphenylmethylsiloxane. The content of the addition reactive group in component A is, for example, 0.0005 mol or more and 0.5 mol or less per 100 g of silicone compound. Component A usually does not have Q units (SiO2) or Si-H groups.

[0017] The weight average molecular weight of component A is, for example, 100,000 to 1,000,000, and may be 100,000 to 500,000. Component A may be in the form of an oil or a crude rubber (silicone rubber).

[0018] The content of component A in composition A is, for example, 20 to 80% by weight, and may be 30 to 70% by weight.

[0019] Composition A may contain two or more types of component A.

[0020] Examples of silicone resins (component B) include Q units and M units (RSiO 1 / 2 ), D units (RSiO) and T units (RSiO3 / 2 and at least one unit selected from the group consisting of M, D, and T units, and a partial condensate thereof. Examples of R in the M units, D units, and T units are, independently of one another, hydrocarbon groups having 1 to 8 carbon atoms, preferably hydrocarbon groups having 1 to 4 carbon atoms, and more preferably alkyl groups having 1 to 4 carbon atoms (which may be linear or branched). A typical example of R is a methyl group. A portion of R may be substituted with a hydroxyl group. Component B generally does not have an addition reactive group. Component B is preferably a so-called MQ resin composed of M units and Q units. R in the M units in an MQ resin may be a methyl group.

[0021] The content ratio (molar ratio) of M units to Q units in the MQ resin is, expressed in terms of M units:Q units, for example, 0.3:1 to 1.5:1, and may be 0.5:1 to 1.3:1.

[0022] The weight average molecular weight of component B is, for example, 1,000 to 10,000, and may be 3,000 to 8,000.

[0023] The content of component B in composition A is, for example, 20 to 80% by weight, and may be 30 to 70% by weight.

[0024] Composition A may contain two or more types of component B.

[0025] The blending ratio (mass ratio) of component A to component B in composition A, expressed as component A:component B, is, for example, 20:80 to 80:20, and may be 25:75 to 50:50.

[0026] The hydrosilane compound (component C) has Si-H groups and reacts with the addition reactive groups of component A to form a crosslinked structure. Examples of component C include hydrogenorganopolysiloxanes and partial condensates thereof. The hydrogenorganopolysiloxane may be either a hydrogenmonoorganopolysiloxane or a hydrogendiorganopolysiloxane. Examples of the organo group, including preferred embodiments, are the same as the examples of the organo group of component A. Some of the organo groups may be substituted with hydroxyl groups. Specific examples of component C are hydrogenmonomethylpolysiloxanes and hydrogendimethylpolysiloxanes, and may also be copolymers of hydrogenmonomethylsiloxane and hydrogendimethylsiloxane.

[0027] The weight average molecular weight of component C is, for example, 100 to 10,000, and may be 100 to 1,000. Component C may be in the form of an oil or a crude rubber (silicone rubber).

[0028] Component C is preferably blended with composition A so that the molar ratio of Si-H groups in component C to the addition reactive groups contained in composition A, such as monovalent organic groups containing alkenyl groups, is, for example, 0.5 to 20, particularly 0.8 to 15.

[0029] Composition A may contain two or more components C.

[0030] The catalyst (component D) is a component that accelerates the curing reaction of composition A. The catalyst is typically a catalyst containing a platinum group element, and is preferably a platinum-based catalyst. The platinum group element contained in component D remains in the cured adhesive layer 11.

[0031] The content of component D in composition A is, for example, 5 to 500 ppm (by weight, the same applies hereinafter), and may be 10 to 200 ppm.

[0032] Composition A may contain components other than those described above as long as the effects of the present invention are obtained. Examples of other components include silicone compounds other than components A, B, and C, reaction inhibitors, antioxidants, and ultraviolet absorbers.

[0033] As the addition reaction curing type silicone pressure-sensitive adhesive, a commercially available addition reaction curing type silicone pressure-sensitive adhesive may be used. An addition reaction curing type silicone pressure-sensitive adhesive other than those included in the above examples may also be used.

[0034] Cured adhesive layer 11 may have a shrinkage percentage X at 260°C of 15% or less in at least one direction in its plane. Shrinkage percentage X may be 14% or less, 13% or less, 12% or less, 11% or less, or even 10% or less. The lower limit of shrinkage percentage X is, for example, 0.01% or more. Cured adhesive layer 11 may have a shrinkage percentage X within the above range in at least two or more directions in its plane, or may have a shrinkage percentage X within the above range in all directions in its plane. When cured adhesive layer 11 is formed by applying composition A in one direction to the surface of a base sheet such as substrate 13A described below, cured adhesive layer 11 may have a shrinkage percentage X within the above range in MD (the application direction of composition A) and / or TD (the direction perpendicular to MD in the plane of cured adhesive layer 11). The shrinkage rate X can be calculated by the formula (D0-D1) / D0×100(%), where D0 is the dimension in the above direction before the heat treatment in which the film formed on a polyimide substrate (25 μm thick) is held in a heating bath held at 260°C for 1 minute, and D1 is the dimension in the same direction after the heat treatment. The dimensions D0 and D1 are measured in an environment of a temperature of 25°C±5°C and a humidity of 50±5%RH.

[0035] The gel fraction of the cured adhesive layer 11 is, for example, 25 to 80 wt %. The gel fraction is preferably 25 to 65 wt %, 30 to 60 wt %, or even 35 to 55 wt %. When the gel fraction is within the above preferred range, the initial adhesive strength (anchoring ability) of the cured adhesive layer 11 to the PTFE film and / or the adhesive strength after heat treatment at 260°C can be improved. A PTFE film, such as a PTFE expanded porous film, is sometimes used for the protective film 2. However, PTFE is a substance with low adhesive properties. In a protective cover member 1 in which the cured adhesive layer 11 and the protective film 2 are bonded, when the gel fraction of the cured adhesive layer 11 is within the above preferred range, the improved adhesive strength reliably prevents deformation of the protective cover member 1 at high temperatures and peeling between the protective film 2 and the adhesive layer 3.

[0036] The gel fraction of the cured adhesive layer 11 can be determined by the following method. A test piece weighing approximately 0.1 g taken from the cured adhesive layer 11 to be evaluated is wrapped in a PTFE porous membrane (e.g., NTF1122 manufactured by Nitto Denko) with an average pore size of 0.2 μm and then tied with a string to prepare a measurement sample. The weight of the measurement sample (weight before immersion C) is then measured. The weight before immersion C corresponds to the total weight of the test piece, the PTFE porous membrane, and the string. Separately, the weight of the envelope B, which is the total weight of the PTFE porous membrane and the string, is measured. The measurement sample is then placed in a 50 mL container filled with toluene and allowed to stand at 23°C for 7 days. The container is then washed with ethyl acetate, after which the measurement sample is removed and transferred to an aluminum cup. The ethyl acetate is then removed by drying at 130°C for 2 hours. The weight of the measurement sample (weight after immersion A) is then measured. The gel fraction can be calculated using the formula: Gel fraction (wt%) = (weight A after immersion - weight B of envelope) / (weight C before immersion - weight B of envelope) x 100. The weight measurement is carried out in an environment with a temperature of 25±5°C and a humidity of 50±5%RH.

[0037] The initial adhesive strength of the cured adhesive layer 11 to the PTFE membrane may be, for example, 1.5 N / 20 mm or more, 1.7 N / 20 mm or more, 1.8 N / 20 mm or more, 2.0 N / 20 mm or more, 2.5 N / 20 mm or more, 3.0 N / 20 mm or more, 3.5 N / 20 mm or more, or even 4.0 N / 20 mm or more. The upper limit of the initial adhesive strength is, for example, 100 N / 20 mm or less. The adhesive strength to the PTFE membrane after heat treatment (260°C, 1 minute) may be, for example, 1.5 N / 20 mm or more, 1.7 N / 20 mm or more, 1.8 N / 20 mm or more, 2.0 N / 20 mm or more, 2.4 N / 20 mm or more, 2.5 N / 20 mm or more, 3.0 N / 20 mm or more, 3.5 N / 20 mm or more, or even 4.0 N / 20 mm or more. The upper limit of the adhesive strength is, for example, 100 N / 20 mm or less.

[0038] The elastic modulus (storage modulus G') of the cured adhesive layer 11 at 250°C is, for example, 5.0 × 10 4 Pa or more than 5.5 x 10 4 Pa or higher, 6.0×10 4 Pa or more, and even 6.5 × 10 4 The upper limit of the elastic modulus at 250°C may be, for example, 1.0 × 10 8 The modulus of elasticity can be measured by the following method using a rheometer. After cutting out the cured adhesive layer 11 to be measured, 2 The above layers are laminated to a thickness of 3 mm or more to obtain a measurement sample. Next, the measurement sample is subjected to temperature measurement starting from 25°C under the measurement conditions of shear mode, frequency 1 Hz, and temperature rise rate 5°C / min using a rheometer (for example, Advanced Rheometric Expansion System (ARES) manufactured by Rheometric Scientific), and the elastic modulus when the temperature reaches 250°C is determined.

[0039] 1B, pressure-sensitive adhesive layer 3 and cured adhesive layer 11 are bonded to protective film 2. However, other layers may be disposed between pressure-sensitive adhesive layer 3 and / or cured adhesive layer 11 and protective film 2. Contraction of cured adhesive layer 11 may affect other layers included in laminate 4. Therefore, the effects of the present invention can be obtained even when other layers are disposed between them.

[0040] 1A and 1B relative to an object is shown in FIG. 2. In the example of FIG. 2, a protective cover member 1 is placed on surface 53 of object 51, which has surface 53 with opening 52. Protective cover member 1 is fixed to surface 53 via adhesive layer 3. In this example, adhesive layer 3 (cured adhesive layer 11) forms bonding surface 12 with surface 53 of object 51.

[0041] The pressure-sensitive adhesive layer 3 may have a laminated structure as long as it includes a cured pressure-sensitive adhesive layer 11. The laminated structure may include two or more pressure-sensitive adhesive layers, and at least one pressure-sensitive adhesive layer selected from the two or more pressure-sensitive adhesive layers may be the cured pressure-sensitive adhesive layer 11, or all of the pressure-sensitive adhesive layers may be the cured pressure-sensitive adhesive layer 11.

[0042] The adhesive layer 3 may comprise an adhesive tape including a substrate and a cured adhesive layer 11 disposed on at least one surface of the substrate. The adhesive tape may be a double-sided adhesive tape. An example of this embodiment is shown in FIG. 3. The adhesive layer 3 in FIG. 3 is a double-sided adhesive tape 14 having a substrate 13A and adhesive layers 13B disposed on both surfaces of the substrate 13A. One adhesive layer 13B is in contact with the protective film 2. The other adhesive layer 13B forms the bonding surface 12 of the protective cover member 1. At least one selected from the two adhesive layers 13B may be a cured adhesive layer 11, or both may be cured adhesive layers 11. The double-sided adhesive tape 14 may be a substrate-less tape that does not have a substrate 13A.

[0043] The adhesive layer 3 in Figures 4A and 4B is a laminated structure combining a single-sided adhesive tape 15 having a substrate 13A and an adhesive layer 13B provided on one side of the substrate 13A, and an adhesive layer 13C. In the adhesive layer 3 in Figure 4A, the adhesive layer 13B of the single-sided adhesive tape 15 forms the bonding surface 12, and the adhesive layer 13C is in contact with the protective film 2. In the adhesive layer 3 in Figure 4B, the adhesive layer 13B of the single-sided adhesive tape 15 is in contact with the protective film 2, and the adhesive layer 13C forms the bonding surface 12. The adhesive layer 13B or the adhesive layer 13C may be the cured adhesive layer 11, or both the adhesive layer 13B and the adhesive layer 13C may be the cured adhesive layer 11. The adhesive layer 13C may have the same structure as the adhesive layer 3 (including an embodiment having the above-mentioned laminated structure), or may be the double-sided adhesive tape 14 described above.

[0044] The substrate 13A is, for example, a film, nonwoven fabric, or foam of resin, metal, or a composite material thereof. Examples of resins include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate (PET), silicone resins, polycarbonate, polyimide, polyamide-imide, polyphenylene sulfide, polyether ether ketone (PEEK), and fluororesin. Examples of fluororesin include polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-ethylene copolymer (ETFE). Examples of metals include stainless steel and aluminum. However, the resins and metals are not limited to the above examples.

[0045] The substrate 13A may contain a heat-resistant material. In this case, depending on the materials of the other layers constituting the protective cover member 1, it may be possible to more reliably withstand high temperatures. Examples of heat-resistant materials include metals and heat-resistant resins. Heat-resistant resins typically have a melting point of 150°C or higher. The melting point of heat-resistant resins may be 160°C or higher, 200°C or higher, 250°C or higher, 260°C or higher, or even 300°C or higher. Examples of heat-resistant resins include silicone resins, polyimides, polyamideimides, polyphenylene sulfide, PEEK, and fluororesins. The fluororesin may be PTFE. PTFE has particularly excellent heat resistance.

[0046] The pressure-sensitive adhesive layer 3 in FIG. 1B is disposed in a partial region of the protective film 2 when viewed perpendicularly to the main surface of the protective film 2. The shape of the pressure-sensitive adhesive layer 3 in FIG. 1B is the shape of the peripheral portion of the protective film 2 when viewed perpendicularly to the main surface of the protective film 2, and more specifically, is a frame shape. In this case, better ventilation and / or sound transmission is possible in region P of the protective film 2 where the pressure-sensitive adhesive layer 3 is not formed compared to the region where the pressure-sensitive adhesive layer 3 is formed. However, the shape of the pressure-sensitive adhesive layer 3 is not limited to the above example.

[0047] The area of ​​the region P of the protective film 2 is, for example, 20 mm 2 The protective cover member 1 having the area of ​​the region P in this range is suitable for placement on, for example, a circuit board or MEMS that normally has a small diameter opening. The lower limit of the area of ​​the region P is, for example, 0.008 mm 2 However, the area of ​​region P may be larger depending on the type of object on which protective cover member 1 is to be placed.

[0048] The thickness of the pressure-sensitive adhesive layer 3 is, for example, 10 to 200 μm.

[0049] The protective film 2 may be non-permeable in the thickness direction or permeable in the thickness direction. When the protective film 2 is permeable in the thickness direction, the placement of the protective cover member 1 can ensure permeability of the opening while preventing the intrusion of foreign matter through the opening of the object. Ensuring permeability can, for example, adjust the pressure through the opening of the object or mitigate pressure fluctuations. An example of mitigating pressure fluctuations is shown below. A semiconductor element may be placed to cover one opening of a through hole provided in a circuit board, and then a heat treatment such as solder reflow may be performed. By placing the protective cover member 1 to cover the other opening, the intrusion of foreign matter into the element through the through hole during the heat treatment can be suppressed. When the protective film 2 is permeable in the thickness direction, the pressure increase in the through hole due to heating is mitigated, preventing damage to the element due to the pressure increase. Examples of semiconductor elements include MEMS (Micro-Electro Mechanical Systems) such as microphones, pressure sensors, and acceleration sensors. These elements have openings that allow air or sound to pass through, and can be placed on the circuit board so that the opening faces the through hole. The protective cover member 1 may be placed on a semiconductor element after manufacture so as to cover the opening of the element. If the protective film 2 is breathable in the thickness direction, the placed protective cover member 1 can function, for example, as a ventilation member that prevents the intrusion of foreign matter through an opening in an object while ensuring breathability through the opening, and / or as a sound-permeable member that prevents the intrusion of foreign matter through an opening in an object while ensuring sound permeability through the opening. Note that even if the protective film 2 is not breathable in the thickness direction, sound can be transmitted by vibration of the protective film 2, and therefore the placed protective cover member 1 can function as a sound-permeable member.

[0050] The air permeability of the protective film 2 that is breathable in the thickness direction is expressed as the air permeability (Gurley air permeability) determined in accordance with the air permeability measurement method B (Gurley method) specified in JIS L1096, and is, for example, 100 seconds / 100 mL or less.

[0051] The protective film 2 may be waterproof. A protective cover member 1 equipped with a waterproof protective film 2 can function, for example, as a waterproof breathable member and / or a waterproof sound-transmitting member after being placed on an object. The waterproof protective film 2 has a water pressure resistance of, for example, 5 kPa or more, as determined in accordance with water resistance test method A (low water pressure method) or method B (high water pressure method) specified in JIS L1092.

[0052] Examples of materials that form the protective film 2 include metals, resins, and composite materials thereof.

[0053] Examples of resins and metals that can form the protective film 2 are the same as the examples of resins and metals that can form the base material 13A, but the resins and metals are not limited to the above examples.

[0054] The protective film 2 may be made of a heat-resistant material. In this case, depending on the materials of the other layers constituting the protective cover member 1, it may be possible to more reliably withstand high-temperature processes such as solder reflow. Examples of heat-resistant materials are as described above in the description of the base material 13A. As an example, the protective film 2 may include a PTFE film.

[0055] The protective film 2, which is breathable in the thickness direction, may include an expanded porous film. The expanded porous film may be an expanded porous film of a fluororesin, particularly an expanded porous PTFE film. The expanded porous PTFE film is usually formed by expanding a paste extrudate or cast film containing PTFE particles. The expanded porous PTFE film is composed of fine PTFE fibrils and may have nodes in which the PTFE is in a state of agglomeration compared to the fibrils. The expanded porous PTFE film can achieve both high levels of performance in preventing the intrusion of foreign matter and high breathability. A known expanded porous film can be used for the protective film 2.

[0056] A stretched porous membrane is prone to shrinkage at high temperatures. Therefore, when protective film 2 includes a stretched porous membrane, the effect of the present invention, in which deformation of protective cover member 1 and peeling from the placement surface are suppressed even at high temperatures, becomes even more advantageous, particularly when cured adhesive layer 11 is in contact with protective film 2.

[0057] The protective film 2 that is breathable in the thickness direction may include a perforated film in which multiple through-holes are formed connecting both main surfaces. The perforated film may be a film in which multiple through-holes are formed in a base film having a non-porous substrate structure, such as a non-porous film. The perforated film may not have any ventilation paths in the thickness direction other than the multiple through-holes. The through-holes may extend in the thickness direction of the perforated film, or may be straight holes that extend linearly in the thickness direction. The opening shape of the through-holes may be circular or elliptical when viewed perpendicularly to the main surface of the perforated film. The perforated film can be formed, for example, by laser processing of the base film, or by perforation processing using ion beam irradiation and subsequent chemical etching.

[0058] The protective film 2 that is breathable in the thickness direction may include a nonwoven fabric, a woven fabric, a mesh, or a net.

[0059] The protective film 2 is not limited to the above example.

[0060] The shape of the protective film 2 in Fig. 1B is rectangular when viewed perpendicular to its main surface. However, the shape of the protective film 2 is not limited to the above example, and may be, for example, a polygon including a square or rectangle, a circle, or an ellipse when viewed perpendicular to its main surface. The polygon may be a regular polygon. The corners of the polygon may be rounded.

[0061] The thickness of the protective film 2 is, for example, 1 to 100 μm.

[0062] The area of ​​the protective film 2 is, for example, 175 mm 2 is less than or equal to 150mm 2 Below, 125mm 2 Below, 100mm 2 Below, 75mm 2 Below, 50mm 2 Below, 25mm 2 Below, 20mm 2 Below, 15mm 2 Below, 10mm 2 Below that, 7.5mm 2The protective cover member 1 having the area of ​​the protective film 2 in the above range is suitable for placement on, for example, a circuit board or MEMS that normally has a small diameter opening. The lower limit of the area of ​​the protective film 2 is, for example, 0.20 mm 2 However, the area of ​​the protective film 2 may be larger depending on the type of object on which the protective cover member 1 is to be placed.

[0063] 1B is disposed on the periphery of the protective film 2 when viewed perpendicularly to the main surface of the protective film 2. In this case, when viewed perpendicularly to the main surface of the protective film 2, the shortest line segment S min The line segment S for the length L1 min The ratio L2 / L1 of the length L2 of the overlapping portion with the pressure-sensitive adhesive layer 3 in the protective cover member 1 may be 0.5 or less, 0.3 or less, 0.2 or less, or even 0.1 or less. The lower limit of the ratio L2 / L1 is, for example, 0.05 or more. The smaller the ratio L2 / L1, the greater the effect of shrinkage of the pressure-sensitive adhesive layer 3 on the protective cover member 1, and in particular, the more likely peeling occurs between the protective film 2 and / or the placement surface and the pressure-sensitive adhesive layer 3. Therefore, when the ratio L2 / L1 is within the above range, the effects of the present invention are more advantageous. The center O of the protective film 2 can be defined as the center of gravity of the shape of the protective film 2 when viewed perpendicular to the main surface of the protective film 2.

[0064] The laminate 4 may include a first adhesive layer located on one main surface of the protective film 2 and a second adhesive layer located on the other main surface of the protective film 2. In this case, for example, one adhesive layer selected from the first adhesive layer and the second adhesive layer allows placement on the surface of an object, while the other adhesive layer allows an additional layer to be placed on top of it, or the other adhesive layer can be bonded to any member and / or surface. At least one adhesive layer selected from the first adhesive layer and the second adhesive layer may be an adhesive layer 3 including a cured adhesive layer 11. As shown in FIG. 5 , both the first adhesive layer located on one main surface 16A of the protective film 2 and the second adhesive layer located on the other main surface 16B may be adhesive layers 3 (3A, 3B) including a cured adhesive layer 11. When both layers are adhesive layers 3, deformation of the protective cover member 1 and peeling from the surface on which it is placed at high temperatures are more reliably suppressed.

[0065] The shape of the adhesive layer 3B in FIG. 5 is the same as the shape of the adhesive layer 3A when viewed perpendicularly to the main surface of the protective film 2. In this case, better ventilation and / or sound transmission is possible in region Q of the protective film 2 where the adhesive layer 3B is not formed compared to the region where the adhesive layer 3B is formed. However, the shape of the adhesive layer 3B is not limited to the above example. The shape of the adhesive layer 3B may be different from the shape of the adhesive layer 3A when viewed perpendicularly to the main surface of the protective film 2. The area of ​​region Q may be in the same range as the area of ​​region P. The area of ​​region Q may be the same as the area of ​​region P.

[0066] The laminate 4 of the protective cover member 1 may include layers other than the protective film 2 and the pressure-sensitive adhesive layer 3. An example of a protective cover member 1 including additional layers is shown in FIG.

[0067] The laminate 4 in FIG. 6 is the same as the laminate 4 in FIG. 5 except that it further includes a cover film 5 covering the protective film 2 on the other main surface 16B side (the side of the pressure-sensitive adhesive layer 3B) of the protective film 2. The cover film 5 is disposed on the pressure-sensitive adhesive layer 3B. Other layers may be disposed between the pressure-sensitive adhesive layer 3B and the cover film 5. The cover film 5 functions as a protective film that protects the protective film 2, for example, until the protective cover member 1 is disposed on the object. The cover film 5 may be peeled off after the protective cover member 1 is disposed on the object. The cover film 5 may cover the entire protective film 2 or a part of it when viewed perpendicular to the main surface of the protective film 2.

[0068] 6 has a tab 6 that protrudes outward from the outer periphery of the protective film 2 when viewed perpendicularly to the main surface of the protective film 2. The tab 6 can be used to peel off the cover film 5. However, the shape of the cover film 5 is not limited to the above example.

[0069] Examples of materials that can form the cover film 5 include metals, resins, and composite materials thereof. Specific examples of materials that can form the cover film 5 are the same as the specific examples of materials that can form the base material 13A.

[0070] The thickness of the cover film 5 is, for example, 200 to 1000 μm.

[0071] The shape of the protective cover member 1 in Figures 1A and 1B is rectangular when viewed perpendicularly to the main surface of the protective film 2. However, the shape of the protective cover member 1 is not limited to the above example. When viewed perpendicularly to the main surface of the protective film 2, the shape may be a polygon including a square or rectangle, a circle, or an ellipse. The polygon may be a regular polygon. The corners of the polygon may be rounded.

[0072] The area of ​​the protective cover member 1 (the area when viewed perpendicularly to the main surface of the protective film 2) is, for example, 175 mm 2 is less than or equal to 150mm 2 Below, 125mm 2 Below, 100mm 2 Below, 75mm 2Below, 50mm 2 Below, 25mm 2 Below, 20mm 2 Below, 15mm 2 Below, 10mm 2 Below that, 7.5mm 2 The protective cover member 1 having an area within the above range is suitable for placement on, for example, circuit boards or MEMS that normally have small-diameter openings. The lower limit of the area of ​​the protective cover member 1 is, for example, 0.20 mm 2 That's all. However, the area of ​​the protective cover member 1 may be larger depending on the type of object on which it is placed. The smaller the area of ​​the protective cover member 1, the more likely it is to deform or peel off from the surface on which it is placed at high temperatures. For this reason, the effects of the present invention are particularly advantageous when the area of ​​the protective cover member 1 is within the above range.

[0073] The object on which the protective cover member 1 is placed is, for example, a semiconductor element such as a MEMS or a circuit board. In other words, the protective cover member 1 may be a component for a semiconductor element, a circuit board, or a MEMS, the object being a semiconductor element, a circuit board, or a MEMS. The MEMS may be a non-sealed element having a vent hole on the surface of the package. Examples of non-sealed MEMS include various sensors that detect air pressure, humidity, gas, airflow, etc., and electroacoustic transducers such as speakers and microphones. The object is not limited to manufactured semiconductor elements or circuit boards, but may also be intermediate products of these elements or boards during the manufacturing process. In this case, the protective cover member 1 can protect the intermediate products during the manufacturing process. Examples of manufacturing processes include a solder reflow process, a dicing process, a bonding process, and a mounting process. The manufacturing process may be a process performed at high temperatures, such as a solder reflow process. The high temperature may be, for example, 200°C or higher, 220°C or higher, 240°C or higher, or even 260°C or higher. The solder reflow process is usually carried out at about 260° C. However, the object is not limited to the above example.

[0074] The surface of the object on which the protective cover member 1 can be placed is typically the outer surface of the object. The surface may also be an internal surface of the object. The surface may be flat or curved. Furthermore, the opening of the object may be the opening of a recess or the opening of a through-hole.

[0075] The protective cover member 1 can be produced by laminating a protective film 2 and a pressure-sensitive adhesive layer 3, for example.

[0076] [Material supply sheet] An example of a component supply sheet of the present invention is shown in Fig. 7. Component supply sheet 21 in Fig. 7 includes a base sheet 22 and a plurality of protective cover members 1 arranged on base sheet 22. Component supply sheet 21 is a sheet for supplying protective cover members 1. Component supply sheet 21 can efficiently supply protective cover members 1 in, for example, a step of placing them on the surface of an object.

[0077] 7, two or more protective cover members 1 are arranged on base sheet 22. The number of protective cover members 1 arranged on base sheet 22 may be one.

[0078] In the example of FIG. 7 , two or more protective cover members 1 are regularly arranged on the base sheet 22. More specifically, the protective cover members 1 are arranged so that the center of each protective cover member 1 is located at an intersection (lattice point) of a rectangular lattice when viewed perpendicular to the surface of the base sheet 22. However, the regularly arranged arrangement of the protective cover members 1 is not limited to the above example. The protective cover members 1 may also be regularly arranged so that the center of each protective cover member 1 is located at an intersection of various lattices, such as a square lattice, an oblique lattice, or a rhombic lattice. Furthermore, the arrangement of the protective cover members 1 is not limited to the above example. For example, the protective cover members 1 may be arranged in a staggered pattern when viewed perpendicular to the surface of the base sheet 22. The center of the protective cover member 1 can be determined as the center of gravity of the shape of the member 1 when viewed perpendicular to the surface of the base sheet 22.

[0079] Examples of materials that make up the base sheet 22 include paper, metal, resin, and composite materials thereof. Examples of metal include stainless steel and aluminum. Examples of resin include polyester such as PET, and polyolefins such as polyethylene and polypropylene. However, the materials that make up the base sheet 22 are not limited to the above examples.

[0080] The protective cover member 1 may be disposed on the base sheet 22 via an adhesive layer (for example, adhesive layer 3) provided on the member 1. In this case, the surface of the base sheet 22 on which the protective cover member 1 is disposed may be subjected to a release treatment to improve releasability from the base sheet 22. The release treatment can be performed by a known method.

[0081] The protective cover member 1 may be placed on the base sheet 22 via an adhesive layer, typically a weak adhesive layer, provided on the surface of the base sheet 22 on which the protective cover member 1 is placed.

[0082] The thickness of the base sheet 22 is, for example, 1 to 200 μm.

[0083] The base sheet 22 in Fig. 7 is in the form of a sheet having a rectangular shape. The shape of the sheet-shaped base sheet 22 is not limited to the above example, and may be a polygon including a square and a rectangle, a circle, an ellipse, or the like. When the base sheet 22 is in the form of a sheet, the member supply sheet 21 can be distributed and used in the form of a sheet. The base sheet 22 may be in the form of a strip, in which case the member supply sheet 21 is also in the form of a strip. The strip-shaped member supply sheet 21 can be distributed as a roll wound around a core.

[0084] The member supply sheet 21 can be produced by placing the protective cover member 1 on the surface of the base sheet 22. [Example]

[0085] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the examples shown below.

[0086] First, the evaluation method for the cured adhesive layer (however, in Comparative Example 4, the acrylic adhesive layer; the same applies hereinafter) will be described.

[0087] [Gel fraction] The gel fraction of the cured adhesive layer was determined by the method described above. The measurement was performed at an environmental temperature of 25°C and a humidity of 50% RH.

[0088] [Elastic modulus at 250℃] The storage modulus (250°C) of the cured adhesive layer was determined by the method described above. The rheometer used was an Advanced Rheometric Expansion System (ARES) manufactured by Rheometric Scientific. The measurement sample was circular, with a surface area of ​​78.5 mm. 2 The thickness was set to 5 mm.

[0089] [Shrinkage rate at 260°C X] The shrinkage rate X of the cured adhesive layer at 260°C was determined as follows. Reference example, Sample B (a square having a three-layer structure of cured adhesive layer / polyimide substrate (thickness 25 μm) / cured adhesive layer, each 1.7 mm on a side) prepared in the comparative example was subjected to a heat treatment in which the sample was held in a heating bath maintained at 260°C for 1 minute. After the treatment, the sample was allowed to cool to 25°C, and the shortest dimension D of the cured adhesive layer was measured in both the MD and TD directions of the cured adhesive layer. min The shortest dimension D was measured for each of the two cured adhesive layers sandwiching the polyimide substrate. min The average value of these was taken as the dimension D1 in each direction after the heat treatment. From the obtained D1, the shrinkage rate X (%) was calculated using the formula: shrinkage rate X = (1.7 - D1) / 1.7 × 100 (%). The shortest dimension D min was determined by image analysis of the magnified image (47x magnification) observed with an optical microscope. min The measurements were carried out at a temperature of 25°C and a humidity of 50% RH.

[0090] [Adhesion to PTFE membrane] The initial adhesive strength of the cured adhesive layer to the PTFE film and the adhesive strength after heat treatment (260°C, 1 minute) were determined by a 180° peel test as follows.

[0091] Each Example , reference example, Sample A (20 mm wide and 150 mm long strip having a three-layer structure of cured adhesive layer / polyimide substrate (25 μm thick) / cured adhesive layer) prepared in the comparative example was bonded, via one of the cured adhesive layers, to the surface of a rectangular fixing plate (made of stainless steel) having a length and width greater than those of Sample A and a sufficient thickness to prevent deformation during testing. Sample A was bonded so that the long and short sides of both plates were parallel to each other. Next, a strip-shaped PTFE membrane (10 μm thick, 50 mm wide, and 150 mm long strip, a microporous membrane with an average pore size of 0.5 μm or less, and a porosity of 40%) was bonded to Sample A so that the PTFE membrane was in contact with the other cured adhesive layer. In microporous membranes with an average pore size of 0.5 μm or less and a porosity of approximately 30 to 50%, the PTFE membrane does not undergo cohesive failure during a peel test, and the contact state with the cured adhesive layer, taking into account bonding with the porous membrane, can be properly ensured, making it possible to properly measure the adhesive strength to the PTFE membrane. The method described in ASTM F316-86 is commonly used to measure the average pore size of PTFE membranes, and an automated measuring device (for example, a Perm Porometer available from Porous Materials Inc., USA) can be used for the measurement. The porosity of a PTFE membrane can be calculated using the formula: Porosity (%) = {1 - (membrane mass [g] / (membrane thickness [cm] × membrane area [cm])} 2 ] × true density of PTFE)) × 100. The true density of PTFE is 2.18 g / cm 2 is.

[0092] The PTFE membrane used in the peel test was prepared as follows. A fluorochemical surfactant (MEGAFAC F-142D, manufactured by DIC Corporation) was added at 1 part by mass per 100 parts by mass of PTFE to a PTFE dispersion (PTFE powder concentration 40% by mass, average PTFE powder particle size 0.2 μm, nonionic surfactant content 6 parts by mass per 100 parts by mass of PTFE). A long polyimide film (125 μm thick) was then immersed in the PTFE dispersion and pulled out, forming a coating film of the PTFE dispersion on the film. The thickness of the coating film was measured using a measuring bar. The coating film was then heated at 100°C for 1 minute and then at 390°C for 1 minute to evaporate and remove the water contained in the dispersion and to bond the remaining PTFE particles together. The immersion and heating process was repeated two more times, after which the resulting PTFE base film (25 μm thick) was peeled off from the polyimide film. Next, the obtained PTFE base membrane was rolled in the MD direction at a rolling ratio of 2.5 times, and then stretched in the TD direction at a stretch ratio of 2.0 times using a tenter to obtain the above-mentioned PTFE membrane. A roll rolling machine was used for rolling, and the roll temperature was set to 170°C. The stretching temperature was 170°C.

[0093] Sample A and the PTFE membrane were bonded together so that the PTFE membrane covered the entire surface of Sample A and the long sides of both membranes were parallel to each other. A manual roller (2 kg mass as specified in JIS Z0237:2009) that compresses the PTFE membrane, Sample A, and the fixed plate was then moved back and forth once with the fixed plate facing downwards. Next, one short side of the fixed plate was fixed to the upper chuck of the tensile tester, and the end of the PTFE membrane facing the upper chuck was peeled off Sample A, folded back 180°, and fixed to the lower chuck of the tensile tester. A 180° peel test was performed to peel the PTFE membrane from Sample A. The pulling speed was 300 mm / min. To ensure measurement accuracy, the measurements for the first 20 mm were ignored. The average of the adhesive strength measurements for at least 60 mm peeled from Sample A was used as the adhesive strength of the cured adhesive layer (unit: N / 20 mm). The peel test was carried out under an environment of 25°C and 50% RH. The test was carried out before and after heat treatment to determine the adhesive strength before heat treatment (initial adhesive strength) and after heat treatment. The heat treatment was carried out by holding Sample A in a heating bath maintained at 260°C for 1 minute.

[0094] Example 1 A mixture (composition a) of 100 parts by weight of Shin-Etsu Chemical Co., Ltd.'s KR3700 and 0.05 parts by weight of a platinum catalyst (Shin-Etsu Chemical Co., Ltd.'s CAT-PL-50T) was prepared as addition reaction curable silicone adhesive composition A. KR3700 contains dimethylpolysiloxane as main component A, MQ resin as main component B, and hydrogendimethylpolysiloxane as main component C. Furthermore, KR3700 does not contain a peroxide curable silicone adhesive.

[0095] Next, composition a was applied in one direction to both main surfaces of a polyimide substrate (strip-shaped, 25 μm thick, 20 mm wide, and 150 mm long), and the entire surface was heated at 130°C for 2 minutes to cure the coating of composition a, thereby obtaining sample A having a three-layer structure of cured adhesive layer / polyimide substrate / cured adhesive layer. Composition a was applied using an applicator so that the thickness after curing was 30 μm. The application direction of composition a was the same on both main surfaces of the polyimide substrate. Sample B was obtained by cutting sample A into a square with sides of 1.7 mm. The direction of each side of the square was the MD (application direction of composition a) or TD (direction perpendicular to the MD within the plane of the cured adhesive layer) of the cured adhesive layer.

[0096] Example 2 Sample A (strip) and Sample B (square) of Example 2 were obtained in the same manner as in Example 1, except that a mixture of 100 parts by weight of X-40-3240 manufactured by Shin-Etsu Chemical Co., Ltd. and 0.05 parts by weight of a platinum catalyst (CAT-PL-50T manufactured by Shin-Etsu Chemical Co., Ltd.) was used as addition reaction curable silicone pressure-sensitive adhesive composition A. X-40-3240 contains dimethylpolysiloxane as main component A, MQ resin as main component B, and hydrogendimethylpolysiloxane as main component C. Furthermore, X-40-3240 does not contain a peroxide-curable silicone pressure-sensitive adhesive.

[0097] Example 3 Sample A (strip) and Sample B (square) of Example 3 were obtained in the same manner as in Example 1, except that a mixture of 75 parts by weight of Shin-Etsu Chemical Co., Ltd.'s KR3700, 25 parts by weight of Shin-Etsu Chemical Co., Ltd.'s KR3704, and 0.05 parts by weight of a platinum catalyst (Shin-Etsu Chemical Co., Ltd.'s CAT-PL-50T) was used as addition reaction curable silicone pressure-sensitive adhesive composition A. KR3704 contains dimethylpolysiloxane as main component A, MQ resin as main component B, and hydrogendimethylpolysiloxane as main component C. Furthermore, KR3704 does not contain a peroxide-curable silicone pressure-sensitive adhesive.

[0098] ( Reference example ) The same procedures as in Example 1 were repeated, except that a mixture of 25 parts by weight of Shin-Etsu Chemical Co., Ltd.'s KR3700, 75 parts by weight of Shin-Etsu Chemical Co., Ltd.'s KR3704, and 0.05 parts by weight of a platinum catalyst (Shin-Etsu Chemical Co., Ltd.'s CAT-PL-50T) was used as the addition reaction curable silicone pressure-sensitive adhesive composition A. Reference example Sample A (strip) and Sample B (square) were obtained.

[0099] (Comparative Example 1) Sample A (strip) and Sample B (square) of Comparative Example 1 were obtained in the same manner as in Example 1, except that a peroxide-curable silicone pressure-sensitive adhesive composition (SH4280 (peroxide content: 1.2 parts by weight) manufactured by Dow Corning Toray Co., Ltd.) was used instead of addition reaction-curable silicone pressure-sensitive adhesive composition A. However, the curing conditions for the coating film were 200°C and 3 minutes.

[0100] (Comparative Example 2) Sample A (strip) and Sample B (square) of Comparative Example 2 were obtained in the same manner as in Example 1, except that a peroxide-curable silicone pressure-sensitive adhesive composition (SH4280 (peroxide content: 2.4 parts by weight) manufactured by Dow Corning Toray Co., Ltd.) was used instead of addition reaction-curable silicone pressure-sensitive adhesive composition A. However, the curing conditions for the coating film were 200°C and 3 minutes.

[0101] (Comparative Example 3) Sample A (strip) and Sample B (square) of Comparative Example 3 were obtained in the same manner as in Example 1, except that a peroxide-curable silicone pressure-sensitive adhesive composition (KR101-10 (peroxide content: 2.4 parts by weight) manufactured by Shin-Etsu Chemical Co., Ltd.) was used instead of addition reaction-curable silicone pressure-sensitive adhesive composition A. However, the curing conditions for the coating film were 200°C and 3 minutes.

[0102] Comparative Example 4 Sample A (strip) and Sample B (square) of Comparative Example 4 were obtained in the same manner as in Example 1, except that an acrylic adhesive composition (Nitto Denko Corporation, No. 5919) was used instead of the addition reaction curable silicone adhesive composition A. However, instead of curing after application, the applied film was dried by heating at 120°C for 3 minutes. The adhesive composition was applied so that the thickness after drying would be 50 μm.

[0103] The evaluation results are shown in Tables 1A and 1B below. In addition, the shrinkage ratio X of each example after the heat treatment (260°C, 1 minute) performed for the evaluation was , reference example, The appearance of Sample B as a comparative example is shown in FIG.

[0104] [Table 1A]

[0105] [Table 1B]

[0106] As shown in Tables 1A and 1B, shrinkage of the cured adhesive layer due to heat treatment was suppressed in Examples compared to Comparative Examples. Furthermore, in Examples 1 to 3, where the gel fraction was in the range of 25 to 65 wt%, shrinkage of the cured adhesive layer due to heat treatment was suppressed in Examples 1 to 3, where the gel fraction was outside the above range. Reference example The adhesive strength to PTFE was improved compared to the initial adhesive strength, and the adhesive strength after heat treatment was improved compared to the initial adhesive strength. As shown in Figure 8, in Comparative Example 1, peeling 61 of the cured adhesive layer from the polyimide substrate occurred. Peeling 61 progressed from the outer periphery of Sample B to the portion indicated by reference numeral 62. [Industrial Applicability]

[0107] The protective cover member of the present invention can be used, for example, in the manufacture of semiconductor elements such as MEMS and / or circuit boards including such elements.

Claims

1. A protective cover member to be placed on a surface of an object having an opening, the member has a shape that covers the opening when placed on the surface, and is composed of a laminate including a protective film containing a metal or a heat-resistant resin having a melting point of 260°C or higher, and a pressure-sensitive adhesive layer; the pressure-sensitive adhesive layer comprises a cured pressure-sensitive adhesive layer of a silicone pressure-sensitive adhesive composition containing only an addition reaction curable silicone pressure-sensitive adhesive as a pressure-sensitive adhesive; the content of the addition reaction curable silicone pressure-sensitive adhesive in the silicone pressure-sensitive adhesive composition is 50% by weight or more; The gel fraction of the cured adhesive layer is 35 to 52% by weight. Protective cover material.

2. The protective cover member according to claim 1 , wherein the heat-resistant resin includes a silicone resin, a polyimide, a polyamide-imide, a polyphenylene sulfide, a PEEK, or a fluororesin.

3. The protective cover member according to claim 1 or 2, wherein the adhesive layer and / or the cured adhesive layer is in contact with the protective film.

4. The protective cover member according to any one of claims 1 to 3, wherein the adhesive layer and / or the cured adhesive layer forms a bonding surface with the surface of the object.

5. The laminate includes a first adhesive layer located on one main surface side of the protective film, and a second adhesive layer located on the other main surface side of the protective film. A protective cover member according to any one of claims 1 to 4.

6. The adhesive layer comprises a substrate containing a metal or a heat-resistant resin having a melting point of 260°C or higher, and the cured adhesive layer disposed on at least one surface of the substrate. The protective cover member according to any one of claims 1 to 5, comprising an adhesive tape.

7. The protective cover member according to claim 6 , wherein the adhesive tape is a double-sided adhesive tape.

8. The protective cover member of claim 6 , wherein the substrate comprises a heat-resistant resin.

9. The protective cover member according to any one of claims 1 to 8, wherein the protective film has air permeability in the thickness direction.

10. The protective cover member according to any one of claims 1 to 9, wherein the protective film comprises a polytetrafluoroethylene film.

11. The area of ​​the protective film is 175 mm 2 The protective cover member according to any one of claims 1 to 10, wherein:

12. When viewed perpendicularly to the main surface of the protective film, the pressure-sensitive adhesive layer is disposed on the peripheral edge of the protective film, The length L of the shortest line segment from the center of the protective film to the outer periphery of the protective film 1 The length L of the part of the shortest line segment that overlaps with the pressure-sensitive adhesive layer, 2 The ratio L 2 / L 1 The protective cover member according to any one of claims 1 to 11, wherein the value of the resistance is 0.3 or less.

13. The protective cover member according to any one of claims 1 to 12, which is for use in a micro-electromechanical system (MEMS).

14. A base sheet and one or more protective cover members disposed on the base sheet, The member supply sheet, wherein the protective cover member is the protective cover member according to any one of claims 1 to 13.

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