Film, method for manufacturing the same, and method for manufacturing semiconductor package

Abstract

The present disclosure provides a film, a method for manufacturing the film, and a semiconductor package using the film, wherein the film has at least a substrate and an antistatic layer, and has the following characteristics: the proportion of the peeled area when a tape peeling test is performed after uniaxial stretching by 300% at 25°C is less than 5%; or when a wiping test is performed after uniaxial stretching by 300% at 25°C, formula (H2-H1) ≥ 0 is satisfied (H1 is the haze before wiping, and H2 is the haze after wiping); or in surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, O / C is in the range of 0.010-0.200 or N / F is in the range of 0.010-0.100.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a film and a method for manufacturing the same, and a method for manufacturing a semiconductor package. BACKGROUND

[0002] A film used in various industrial fields is sometimes provided with an antistatic layer in order to suppress charging of the film.

[0003] For example, a semiconductor element is mounted on a substrate in a form of being sealed in a package in order to be isolated from and protected from an external atmosphere. Sealing of the semiconductor element uses a curable resin such as an epoxy resin. The resin sealing is performed by disposing the semiconductor element at a prescribed site inside a mold, filling the curable resin inside the mold, and curing the same. As a method of sealing, a transfer molding method and a compression molding method are generally known. In the sealing of the semiconductor element, in order to improve the releasability of the package from the mold, a releasing film is often disposed on the inner surface of the mold. For example, Patent Documents 1 to 3 describe films suitable for manufacturing semiconductor packages.

[0004] In a case where the releasing film is used in the sealing of the semiconductor element, static electricity is generated when the film is peeled from the package, and the film is likely to be charged. The charged film can damage or destroy the semiconductor package due to discharge. In addition, the damaged semiconductor package can also have poor resistance to static electricity in a use environment. Therefore, from the viewpoints of productivity of the semiconductor package and resistance to static electricity of the semiconductor package in a use environment, it is preferable to use a film with an antistatic layer as the releasing film.

[0005] In Patent Document 2, as a releasing film in the manufacture of a semiconductor package, a film containing at least one antistatic agent selected from a conductive polymer and a conductive metal oxide is proposed.

[0006] Prior Art Documents

[0007] Patent Documents

[0008] Patent Document 1: International Publication No. 2015 / 133630

[0009] Patent Document 2: International Publication No. 2016 / 093178

[0010] Patent Document 3: International Publication No. 2016 / 125796 SUMMARY

[0011] PROBLEMS TO BE SOLVED BY THE INVENTION

[0012] However, there is a demand for further improvement in the antistatic properties of the film. For example, in recent years, as a result of the demand for miniaturization and thinness of semiconductor products, there has been an increasing demand for reduction in the thickness of semiconductor packages. Consequently, it is desirable that the thickness of the sealing resin also be thin. However, it is known that if the thickness of the sealing resin is thinned, the package is easily damaged by the charge generated at the time of film peeling. Therefore, there is a demand for a film having higher antistatic properties.

[0013] In view of the above, the present disclosure relates to a film having excellent antistatic properties, a method for producing the same, and a method for producing a semiconductor package using the same.

[0014] Means for solving the technical problem

[0015] The means for solving the above technical problem include the following embodiments.

[0016] <1> A film comprising at least a substrate and an antistatic layer,

[0017] The proportion of the peeling area when a tape peeling test is performed under the following conditions after uniaxial stretching by 300% at 25°C is less than 5%:

[0018] The proportion of the peeling area of the film with respect to the area of the adhesive portion of Cellotape (registered trademark) is obtained by pressing Cellotape (registered trademark) back and forth 5 times with a roll at a load of 4 kg on the surface of the antistatic layer side of the film, peeling the Cellotape (registered trademark) at a speed of 100 m / min in the direction of 180° with respect to the film within 5 minutes.

[0019] <2> The film according to <1>, wherein formula (H2-H1) ≥ 0 is satisfied when a wiping test is performed under the following conditions after uniaxial stretching by 300% at 25°C:

[0020] The wiping of the film is performed by rubbing the surface of the antistatic layer side of the film with a nonwoven fabric to which acetone is attached back and forth 20 times at a load of 4 kg, and the haze before and after wiping is measured at the same part of the film, with the haze before wiping being set as H1 and the haze after wiping being set as H2.

[0021] <3> The film according to <1> or <2>, wherein in the chemical composition analysis of the surface of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, O / C is in the range of 0.010 to 0.200.

[0022] <4> The film according to any one of <1> to <3>, wherein in the chemical composition analysis of the surface of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, N / F is in the range of 0.010 to 0.100.

[0023] <5> A film comprising at least a substrate and an antistatic layer,

[0024] 25°C after uniaxial stretching by 300% satisfies formula (H2-H1) ≥ 0 when a wiping test is performed under the following conditions:

[0025] The film is wiped by rubbing the surface of the antistatic layer side of the film with a nonwoven fabric to which acetone is attached back and forth 20 times with a load of 4 kg, the haze before and after wiping is measured at the same part of the film, and the haze before wiping is set as Hl and the haze after wiping is set as H2.

[0026] <6> The film according to <5>, wherein, in surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, O / C is in the range of 0.010 to 0.200.

[0027] <7> The film according to <5> or <6>, wherein, in surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, N / F is in the range of 0.010 to 0.100.

[0028] <8> A film comprising at least a substrate and an antistatic layer,

[0029] In surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, O / C is in the range of 0.010 to 0.200.

[0030] <9> The film according to <8>, wherein, in surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, N / F is in the range of 0.010 to 0.100.

[0031] <10> A film comprising at least a substrate and an antistatic layer,

[0032] In surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, N / F is in the range of 0.010 to 0.100.

[0033] <11> The film according to any one of <1> to <10>, wherein the surface of the antistatic layer side of the substrate is subjected to plasma treatment.

[0034] <12> The film according to any one of <1> to <11>, wherein the substrate comprises at least one selected from the group consisting of a fluororesin, a polymethylpentene, a syndiotactic polystyrene, and a polycycloolefin.

[0035] <13> The film according to any one of <1> to <12>, wherein the substrate comprises at least one selected from the group consisting of ethylene-tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer, and tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer.

[0036] <14> The film according to any one of <1> to <13>, further comprising an adhesive layer on a surface of the antistatic layer opposite to the substrate.

[0037] <15> The film according to any one of <1> to <14>, which is a release film used in a process of sealing a semiconductor element with a curable resin.

[0038] <16> A method for producing a film, comprising:

[0039] plasma-treating a surface of a substrate, and

[0040] providing an antistatic layer on the plasma-treated substrate or providing an antistatic layer on the plasma-treated substrate at least through a third layer adjacent to the substrate,

[0041] in a surface chemical composition analysis of the antistatic layer side of the substrate after the plasma treatment by X-ray photoelectron spectroscopy, O / C is in the range of 0.010 to 0.200, or N / F is in the range of 0.010 to 0.100, or both.

[0042] <17> The method for producing a film according to <16>, wherein the plasma treatment is performed in the presence of argon gas, ammonia gas, or nitrogen gas containing 10% by volume or less of hydrogen gas or not containing hydrogen gas.

[0043] <18> The method for producing a film according to <16> or <17>, further comprising corona-treating a surface of the substrate before the plasma treatment.

[0044] <19> The method for producing a film according to any one of <16> to <18>, comprising further providing an adhesive layer on a surface of the antistatic layer opposite to the substrate.

[0045] <20> A method for producing a semiconductor package, comprising:

[0046] arranging the film according to any one of <1> to <15> or the film produced by the method according to any one of <16> to <19> on an inner surface of a mold,

[0047] arranging a substrate provided with a semiconductor element in the mold provided with the film,

[0048] sealing the semiconductor element in the mold with a curable resin to produce a sealed body, and

[0049] releasing the sealed body from the mold.

[0050] Effects of Invention

[0051] According to the present disclosure, there is provided a film excellent in antistatic properties, a method for producing the same, and a method for producing a semiconductor package using the film. BRIEF DESCRIPTION OF DRAWINGS

[0052] Figure 1 A schematic cross-sectional view of a film according to one embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0053] The following describes modes for implementing the embodiments of the present disclosure in detail. However, the embodiments of the present disclosure are not limited to the following embodiments. In the following embodiments, the constituent elements (including element steps, etc.) are not necessarily essential unless otherwise specifically indicated. The same applies to numerical values and ranges thereof, and the embodiments of the present disclosure are not limited thereto.

[0054] In the present disclosure, the term "step" includes a step that is independent of other steps, and also includes a step whose purpose can be achieved even if it cannot be clearly distinguished from other steps.

[0055] In the present disclosure, a numerical range indicated by "~" includes a range in which the numerical values indicated by the front and rear of "~" are minimum and maximum values, respectively.

[0056] In the present disclosure, the upper limit value or the lower limit value of a numerical range indicated in a hierarchical manner can be replaced with the upper limit value or the lower limit value of another numerical range indicated in a hierarchical manner. In addition, in the present disclosure, the upper limit value or the lower limit value of a numerical range can be replaced with a value shown in the examples.

[0057] In the present disclosure, each component can include a plurality of respective substances. In the case where a plurality of respective substances of each component are present in a composition, unless otherwise specified, the content or the amount of each component refers to the total content or the total amount of the plurality of substances present in the composition.

[0058] In the present disclosure, the configuration of the embodiments is not limited to the structures shown in the drawings when the embodiments are described with reference to the drawings. In addition, the sizes of the members in the drawings are illustrative, and the relative relationship of the sizes between the members is not limited thereto.

[0059] In the present disclosure, "unit" of a polymer means a portion present in a polymer that constitutes the polymer, which is derived from a monomer. In addition, a unit whose structure is chemically converted after the formation of a polymer is also referred to as a unit. Furthermore, depending on the case, units derived from respective monomers are referred to by the name of the monomer plus the name of the unit.

[0060] In the present disclosure, a film and a sheet are referred to as "film" regardless of the thickness thereof.

[0061] In the present disclosure, acrylate and methacrylate are collectively referred to as "(meth)acrylate", and acrylic acid and methacrylic acid are collectively referred to as "(meth)acrylic acid".

[0062] In the present disclosure, the film of the first to fourth embodiments is sometimes referred to as "film of the present disclosure".

[0063] Film

[0064] The film of the first embodiment of the present disclosure at least has a substrate and an antistatic layer, and the proportion of the peeling area when a tape peeling test is performed under the following conditions after uniaxial stretching by 300% at 25°C is less than 5%:

[0065] The Cellotape (registered trademark) is pressure-bonded to the surface of the antistatic layer side of the film with a roll with a load of 4 kg for 5 times to and fro, and the Cellotape (registered trademark) is peeled off at a speed of 100 m / min within 5 minutes in a direction of 180° with respect to the film to obtain the proportion of the peeling area of the film with respect to the area of the bonding portion of the Cellotape (registered trademark).

[0066] Here, the bonding portion of the Cellotape (registered trademark) refers to the portion on the surface of the film to which the Cellotape (registered trademark) is bonded.

[0067] The film of the second embodiment of the present disclosure at least has a substrate and an antistatic layer, and satisfies the formula (H2-H1) ≥ 0 when a wiping test is performed under the following conditions after uniaxial stretching by 300% at 25°C:

[0068] The film is wiped by rubbing the surface of the antistatic layer side of the film with a nonwoven fabric to which acetone is attached for 20 times to and fro with a load of 4 kg. The haze before and after wiping is measured at the same portion of the film, and the haze before wiping is set as H1 and the haze after wiping is set as H2.

[0069] The film of the third embodiment of the present disclosure at least has a substrate and an antistatic layer, and in the chemical composition analysis of the surface of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, O / C is in the range of 0.010 to 0.200.

[0070] The membrane of the fourth embodiment of this disclosure has at least a substrate and an antistatic layer, and in the surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, the N / F ratio is in the range of 0.010 to 0.100.

[0071] The films of the first to fourth embodiments described above exhibit excellent antistatic properties. The reason for this may not be clear, but it is speculated that the excellent adhesion of the antistatic layer during film stretching contributes to the film's antistatic performance. The films of the first to fourth embodiments exhibit excellent adhesion of the antistatic layer, thus resulting in high antistatic performance. For example, when the film is stretched, if the antistatic layer has excellent adhesion to adjacent layers, the antistatic layer is less prone to peeling or cracking, and the conductive path is easily maintained. It can be speculated that the static electricity generated thereby easily escapes to the substrate, resulting in excellent antistatic performance.

[0072] The membrane disclosed herein only needs to have a substrate and an antistatic layer; other components are not particularly limited. A schematic cross-sectional view of an embodiment of the membrane is shown in [image description missing]. Figure 1 . Figure 1 The membrane 1 shown has an antistatic layer 3 on the substrate 2. In addition to the substrate 2 and the antistatic layer 3, the membrane 1 may also have other layers. The constituent elements of the membrane of this disclosure will be described in detail below.

[0073] <Substrate>

[0074] The material of the substrate is not particularly limited, but it is preferable to contain resin. In one embodiment, from the viewpoint of the film's release properties, the substrate preferably contains a resin with release properties (hereinafter also referred to as "release resin"). A release resin refers to a resin whose layer has release properties. Examples of release resins include fluoropolymers, polymethylpentene, syndiotactic polystyrene, polycyclic olefins, silicone rubber, polyester elastomers, polybutylene terephthalate, and non-stretchable nylon. From the viewpoints of excellent release properties, heat resistance, strength, and elongation at high temperatures, fluoropolymers, polymethylpentene, syndiotactic polystyrene, and polycyclic olefins are preferred, and from the viewpoint of excellent release properties, fluoropolymers are more preferred. The resin contained in the substrate may be used alone or in combination with two or more types. The substrate is particularly preferably composed of only fluoropolymer. However, even when it is composed of only fluoropolymer, it is permissible to include resins other than fluoropolymer without impairing the effect of the invention.

[0075] From the viewpoint of excellent mold release properties and heat resistance, fluoroolefin polymers are preferred as fluoropolymers. Fluoroolefin polymers are polymers having units based on fluoroolefins. Fluoroolefin polymers may also have other units besides those based on fluoroolefins.

[0076] As the fluorinated olefin, tetrafluoroethylene (TFE), fluoroethylene, vinylidene fluoride, trifluoroethylene, hexafluoropropylene, chlorotrifluoroethylene, and the like can be exemplified. The fluorinated olefin can be used singly or in combination of two or more kinds.

[0077] As the fluorinated olefin polymer, ethylene-tetrafluoroethylene copolymer (ETFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer (PFA), tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer (THV), and the like can be exemplified. From the viewpoint of mechanical properties, at least one selected from the group consisting of ETFE and FEP is preferable. The fluorinated olefin polymer can be used singly or in combination of two or more kinds.

[0078] From the viewpoint of large elongation at high temperature, as the fluorinated olefin polymer, ETFE is preferable. ETFE is a copolymer having a TFE unit and an ethylene unit (hereinafter also referred to as "E unit").

[0079] As the ETFE, a polymer having a TFE unit, an E unit, and a unit based on a third monomer other than TFE and ethylene is preferable. By the kind and content of the unit based on the third monomer, the crystallinity of the ETFE is easily adjusted, and thus the storage modulus or other tensile properties of the base material are easily adjusted. For example, by making the ETFE have a unit based on a third monomer (particularly, a monomer having a fluorine atom), the tensile strength and elongation at high temperature (particularly, around 180°C) tend to increase.

[0080] As the third monomer, a monomer having a fluorine atom and a monomer not having a fluorine atom can be exemplified.

[0081] As the monomer having a fluorine atom, the following monomers (al) to (a5) can be exemplified.

[0082] Monomer (al): a fluorinated olefin having a carbon number of 2 or 3.

[0083] Monomer (a2): a fluoroalkyl vinyl ether represented by the formula: CY=CH2 (wherein X and Y are each independently a hydrogen atom or a fluorine atom, and n is an integer of 2 to 8). n CY=CH2 (wherein X and Y are each independently a hydrogen atom or a fluorine atom, and n is an integer of 2 to 8).

[0084] Monomer (a3): a fluoro vinyl ether.

[0085] Monomer (a4): a fluoro vinyl ether having a functional group.

[0086] Monomer (a5): a fluorine-containing monomer having an alicyclic structure.

[0087] As the monomer (al), fluoroethylene (trifluoroethylene, vinylidene fluoride, fluoroethylene, chlorotrifluoroethylene, and the like), fluoropropylene (hexafluoropropylene (HFP), 2-hydropentafluoropropylene, and the like), and the like can be exemplified.

[0088] As the monomer (a2), a monomer in which n is 2 to 6 is preferred, and a monomer in which n is 2 to 4 is more preferred. Further, a monomer in which X is a fluorine atom and Y is a hydrogen atom, i.e., a (perfluoroalkyl)ethylene, is preferred.

[0089] As specific examples of the monomer (a2), the following compounds can be given.

[0090] CF3CF2CH=CH2,

[0091] CF3CF2CF2CF2CH=CH2((perfluorobutyl)ethylene (PFBE))

[0092] CF3CF2CF2CF2CF=CH2,

[0093] CF2HCF2CF2CF=CH2,

[0094] CF2HCF2CF2CF2CF=CH2, and the like.

[0095] As specific examples of the monomer (a3), the following compounds can be given. Further, the monomers in the following are cyclization-polymerizable monomers.

[0096] CF2=CFOCF3,

[0097] CF2=CFOCF2CF3,

[0098] CF2=CFO(CF2)2CF3(perfluoro(propyl vinyl ether) (PPVE))

[0099] CF2=CFOCF2CF(CF3)O(CF2)2CF3,

[0100] CF2=CFO(CF2)3O(CF2)2CF3,

[0101] CF2=CFO(CF2CF(CF3)O)2(CF2)2CF3,

[0102] CF2=CFOCF2CF(CF3)O(CF2)2CF3,

[0103] CF2=CFOCF2CF=CF2,

[0104] CF2=CFO(CF2)2CF=CF2, and the like.

[0105] As specific examples of the monomer (a4), the following compounds can be given.

[0106] CF2=CFO(CF2)3CO2CH3,

[0107] CF2=CFOCF2CF(CF3)O(CF2)3CO2CH3,

[0108] CF2=CFOCF2CF(CF3)O(CF2)2SO2F, etc.

[0109] As specific examples of the monomer (a5), mention can be made of perfluoro(2,2-dimethyl-l,3-dioxolane), 2,2,4-trifluoro-5-trifluoromethoxy-l,3-dioxolane, perfluoro(2-methylene-4-methyl-l,3-dioxolane), etc.

[0110] As monomers not having a fluorine atom, mention can be made of the following monomers (bl) to (b4).

[0111] Monomer (bl): olefins.

[0112] Monomer (b2): vinyl esters.

[0113] Monomer (b3): vinyl ethers.

[0114] Monomer (b4): unsaturated acid anhydrides.

[0115] As specific examples of the monomer (bl), mention can be made of propylene, isobutylene, etc.

[0116] As specific examples of the monomer (b2), mention can be made of vinyl acetate, etc.

[0117] As specific examples of the monomer (b3), mention can be made of ethyl vinyl ether, butyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, etc.

[0118] As specific examples of the monomer (b4), mention can be made of maleic anhydride, itaconic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, etc.

[0119] The third monomer can be used singly or in combination of two or more.

[0120] As the third monomer, from the viewpoint of easy adjustment of crystallinity and the viewpoint of excellent tensile strength and elongation at high temperatures (particularly around 180°C), monomers (a2), HFP, PPVE and vinyl acetate are preferred, HFP, PPVE, CF3CF2CH=CH2and PFBE are more preferred, and PFBE is further preferred. That is, as the ETFE, a copolymer having a unit based on TFE, a unit based on E and a unit based on PFBE is preferred.

[0121] The molar ratio of TFE units to E units in the ETFE (TFE units / E units) is preferably 80 / 20 to 40 / 60, more preferably 70 / 30 to 45 / 55, and further preferably 65 / 35 to 50 / 50. When the TFE units / E units are within the above range, the heat resistance and mechanical strength of the ETFE are excellent.

[0122] The proportion of units based on the third monomer in the ETFE relative to the total of all units constituting the ETFE (100 mol%) is preferably 0.01 to 20 mol%, more preferably 0.10 to 15 mol%, and further preferably 0.20 to 10 mol%. When the proportion of units based on the third monomer is within the above range, the heat resistance and mechanical strength of the ETFE are excellent.

[0123] When the units based on the third monomer contain PFBE units, the proportion of PFBE units relative to the total of all units constituting the ETFE (100 mol%) is preferably 0.5 to 4.0 mol%, more preferably 0.7 to 3.6 mol%, and further preferably 1.0 to 3.6 mol%. When the proportion of PFBE units is within the above range, the tensile elastic modulus at 180°C of the film can be adjusted to within the above range. In addition, the tensile strength and elongation at high temperatures, particularly around 180°C, are improved.

[0124] The substrate can be composed only of the release resin, or can contain other components in addition to the release resin. As the other components, lubricants, antioxidants, antistatic agents, plasticizers, release agents, and the like can be exemplified. From the viewpoint of not easily contaminating the mold, the substrate preferably does not contain other components.

[0125] The thickness of the substrate is preferably 10 to 500 μm, more preferably 25 to 250 μm, and further preferably 25 to 125 μm. When the thickness of the substrate is below the upper limit of the above range, the film can be easily deformed, and the mold followability is excellent. When the thickness of the substrate is above the lower limit of the above range, the handling of the film, for example, roll-to-roll handling, is easy, and wrinkles are not easily generated even when the film is stretched.

[0126] The thickness of the substrate can be measured by the Bl method of ISO 4591:1992 (JIS K7130:1999) (a method for measuring the thickness by the mass method using a test piece collected from a plastic film or sheet). Hereinafter, the thickness of each layer of the film is also the same.

[0127] The surface of the substrate can have a surface roughness. The arithmetic mean roughness Ra of the surface of the substrate is preferably 0.2 to 3.0 μm, and more preferably 0.5 to 2.5 μm. When the arithmetic mean roughness Ra of the surface of the substrate is above the lower limit of the above range, the release property is more excellent. When the arithmetic mean roughness Ra of the surface of the substrate is below the upper limit of the above range, pinholes are not easily generated on the film.

[0128] The arithmetic average roughness Ra was measured in accordance with JIS B0601:2013 (ISO 4287:1997, Amd.1:2009). The reference length lr (critical value λc) for the roughness curve was 0.8 mm.

[0129] In the surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy (hereinafter referred to as "XPS"), the O / C of the film of the present disclosure is preferably in the range of 0.010 to 0.200. O / C in the above range tends to obtain excellent antistatic properties. O / C can be 0.030 to 0.150, or 0.040 to 0.100.

[0130] The O / C of the film of the third embodiment of the present disclosure is in the range of 0.010 to 0.200.

[0131] In the surface chemical composition analysis of the antistatic layer side of the substrate by XPS, the N / F of the film of the present disclosure is preferably in the range of 0.010 to 0.100. N / F in the above range tends to obtain excellent antistatic properties. N / F can be 0.010 to 0.090, or 0.010 to 0.080.

[0132] The N / F of the film of the fourth embodiment of the present disclosure is in the range of 0.010 to 0.100.

[0133] In one embodiment, it is preferable to satisfy both the above range of O / C and the above range of N / F.

[0134] XPS is a method of quantifying the amount of elements present on the surface of a material or the like, and can quantify each element such as carbon (C), oxygen (O), fluorine (F), and nitrogen (N). In the measurement of O / C and N / F, the analysis object of XPS is a depth of 2 to 8 nm from the surface of the measurement object. The information and analysis conditions of the analysis device are as follows.

[0135] Analysis device: Quantera PHI manufactured by Ulvac-Phi Co., Ltd.

[0136] X-ray source: Al Kα 14kv

[0137] Beam diameter: 100 μm Φ

[0138] Measurement field: 800 x 300 μm 2

[0139] Measurement mode: Narrow spectrum measurement

[0140] Measurement elements and measurement area of the binding energy of each element, and the number of counts:

[0141] C 1s: 278 to 297 eV, 2 times in total

[0142] O 1s: 525 to 544 eV, 3 times in total

[0143] N 1s: 392 to 411 eV, 8 times in total

[0144] F 1s: 680 to 699 eV, 1 time in total

[0145] Binding energy: 224.0 eV

[0146] Energy level: 0.4 eV

[0147] Number of cycles: 8 cycles

[0148] Neutralization gun: used

[0149] Angle of detector to sample surface: 45°

[0150] In the measurement of N / F and O / C, the elements to be measured by XPS are C, O, F, and N, and the proportions of F and N in the total (unit: Atomic %) are taken as the amounts of the respective atoms. Then, based on the values of the Atomic %, N / F and O / C are calculated.

[0151] The surface of the substrate that is adjacent to the other layer can be subjected to any surface treatment. As the surface treatment, corona treatment, plasma treatment, silane coupling agent coating, adhesive coating, and the like can be exemplified. From the viewpoint of the adhesion of the substrate to the other layer, corona treatment or plasma treatment is preferred.

[0152] From the viewpoint of the adhesion of the layer adjacent to the substrate, the surface of the antistatic layer side of the substrate is preferably subjected to plasma treatment. It has also been found that plasma treatment has a tendency to improve the antistatic properties of the film.

[0153] The conditions of plasma treatment are not particularly limited. In one embodiment, plasma treatment can be performed in the presence of argon (Ar) gas; ammonia (NH3) gas; or nitrogen (N2) gas with or without 10% by volume or less of hydrogen (H2) gas.

[0154] In the case where plasma treatment is performed in the presence of argon gas, a functional group such as a hydroxyl group, a carbonyl group, a carboxyl group, or the like can be introduced into the surface of the substrate.

[0155] In the case where plasma treatment is performed in the presence of ammonia gas, a functional group such as a hydroxyl group, a carbonyl group, a carboxyl group, an amino group, an amide group, or the like can be introduced into the surface of the substrate.

[0156] When the plasma treatment is performed in the presence of nitrogen, a functional group such as an amino group or an amide group can be introduced into the surface of the substrate. When hydrogen is mixed in the nitrogen at a concentration of 10% by volume or less, the functional group such as the amino group or the amide group can be more effectively introduced.

[0157] By this, the N / F of the surface of the substrate can be adjusted to the above range, or the O / C of the surface of the substrate can be adjusted to the above range, or both of them can be satisfied.

[0158] When hydrogen is mixed in the nitrogen, the concentration of the hydrogen can be 0.01 to 10% by volume, can be 1 to 10% by volume, or can be 1 to 5% by volume.

[0159] The pressure of the atmosphere in the plasma treatment is preferably atmospheric pressure (about 760 torr) or a low pressure condition in which the pressure is reduced from the atmospheric pressure. The lower the pressure, the smaller the consumed power to generate the plasma. On the other hand, from the viewpoint of making the concentration of the generated plasma sufficient, it is preferable that the pressure is not too low. From the above viewpoint, the pressure of the atmosphere in the plasma treatment can be 0.001 to 760 torr, can be 0.05 to 10 torr, or can be 0.05 to 1 torr.

[0160] From the viewpoint of easily introducing a moderate functional group into the substrate, the discharge power in the plasma treatment can be 0.1 to 150 kW, 0.5 to 120 kW, 1 to 100 kW, or 1 to 50 kW.

[0161] In one embodiment, the plasma treatment can be performed until W•t / F (W•sec / (m 3 / second) calculated from the discharge power (W), the treatment time (t), and the gas flow rate (F) reaches a range of 0.3 x 10 12 to 60.0 x 10 12 , can be performed until it reaches a range of 0.5 x 10 12 to 40.0 x 10 12 , or can be performed until it reaches a range of 1.0 x 10 12 to 10.0 x 10 12 . When W•t / F is in the above range, a moderate functional group is easily introduced into the substrate, and more favorable antistatic properties tend to be obtained.

[0162] The surface of the substrate can be further subjected to a corona treatment in addition to the plasma treatment, or can be further subjected to a corona treatment before the plasma treatment. When the corona treatment is further performed before the plasma treatment, the strength of the substrate tends to be favorable. The reason is not necessarily clear, but it is presumed that even when the plasma strength is high in the plasma treatment, the material decomposition of the surface of the substrate can be suppressed by performing the corona treatment in advance.

[0163] The contact angle of the surface of the antistatic layer side of the base material is preferably 50 to 100°, and can be 60 to 100° or 70 to 100°. The contact angle is obtained by a contact angle meter (for example, DMs-401 manufactured by Kyowa Interface Science Co., Ltd.).

[0164] The base material can be a single layer or can have a multilayer structure. As the multilayer structure, a structure in which a plurality of layers each containing a release resin are stacked can be given. In this case, the release resins contained in the plurality of layers can be the same or different. From the viewpoints of mold followability, tensile elongation, manufacturing cost, and the like, the base material is preferably a single layer.

[0165] <Antistatic Layer>

[0166] The antistatic layer is not particularly limited as long as it is a layer having an antistatic function. The antistatic layer can be provided on the base material in contact with the base material, or can be provided on the base material at least through a third layer adjacent to the base material.

[0167] The antistatic layer can contain an antistatic agent. As the antistatic agent, ionic liquid, conductive polymer, metal ion-conductive salt, conductive metal oxide, and the like can be given. The antistatic agent can be used alone as one kind, or two or more kinds can be used in combination.

[0168] The conductive polymer refers to a polymer in which electrons move and diffuse along the skeleton of the polymer. As the conductive polymer, polyaniline-based polymer, polyacetylene-based polymer, poly(p-phenylene)-based polymer, polypyrrole-based polymer, polythiophene-based polymer, polyvinylcarbazole-based polymer, and the like can be given.

[0169] As the metal ion-conductive salt, lithium salt compounds and the like can be given.

[0170] As the conductive metal oxide, tin oxide, tin-doped indium oxide, antimony-doped tin oxide, phosphorus-doped tin oxide, zinc antimonate, antimony oxide, and the like can be given.

[0171] As the antistatic agent, at least one kind selected from the group consisting of polyaniline polymer, polyacetylene polymer, poly(p-phenylene) polymer, polypyrrole polymer, polythiophene polymer, and polyvinylcarbazole polymer is preferred from the viewpoints of excellent heat resistance and conductivity.

[0172] The antistatic agent is preferably dispersed in a resin binder. That is, the antistatic layer is preferably a layer in which the antistatic agent is dispersed in a resin binder.

[0173] As the resin adhesive, heat resistance is preferable. For example, in the case where the film is used in a sealing process of a semiconductor, a film having heat resistance at about 180°C is preferable. From the viewpoint of excellent heat resistance, the resin adhesive preferably contains at least one selected from the group consisting of an acrylic resin, a silicone resin, a polyurethane resin, a polyester resin, a polyamide resin, a vinyl acetate resin, an ethylene-vinyl acetate copolymer, an ethylene-vinyl alcohol copolymer, a chlorotrifluoroethylene-vinyl alcohol copolymer, and a tetrafluoroethylene-vinyl alcohol copolymer. Among them, from the viewpoint of excellent mechanical strength, at least one (for example, only an acrylic resin) selected from the group consisting of an acrylic resin, a silicone resin, a polyurethane resin, a polyester resin, a polyamide resin, a vinyl acetate resin, an ethylene-vinyl acetate copolymer, an ethylene-vinyl alcohol copolymer, a chlorotrifluoroethylene-vinyl alcohol copolymer, and a tetrafluoroethylene-vinyl alcohol copolymer is preferable. Further, from the viewpoint of excellent heat resistance and dispersibility of the antistatic agent, a polyester resin and an acrylic resin are preferable.

[0174] In the antistatic layer, the resin adhesive can be crosslinked. If the resin adhesive is crosslinked, heat resistance is excellent compared to the case where it is not crosslinked.

[0175] From the viewpoint of sufficiently exerting the antistatic function, the content of the antistatic agent in the antistatic layer is preferably an amount that achieves a surface resistance value of the film in the range described later.

[0176] In one embodiment, in the case where the antistatic layer is a layer in which the antistatic agent is dispersed in the resin adhesive, the content of the antistatic agent with respect to the resin adhesive can be 3 to 50% by mass, or can be 5 to 20% by mass. If the content of the antistatic agent is above the lower limit value of the range described above, the surface resistance value of the film easily falls within the preferable range. If the content of the antistatic agent is below the upper limit value of the range described above, the adhesion of the antistatic layer easily becomes good.

[0177] An additive other than the antistatic agent can be contained in the antistatic layer. As the additive, a lubricant, a colorant, a coupling agent, and the like can be exemplified.

[0178] As the lubricant, a microbead composed of a thermoplastic resin, fumed silica, polytetrafluoroethylene (PTFE) microparticles, and the like can be exemplified.

[0179] As the colorant, various organic colorants and inorganic colorants can be exemplified, and more specifically, cobalt blue, red iron oxide, a cyanine, and the like can be exemplified.

[0180] As the coupling agent, a silane coupling agent, a titanate coupling agent, and the like can be exemplified.

[0181] The thickness of the antistatic layer is preferably 0.05 to 3.0 μm, more preferably 0.1 to 2.5 μm. When the thickness of the antistatic layer is equal to or greater than the lower limit of the above range, the antistatic layer exhibits excellent conductivity and antistatic properties. When the thickness of the antistatic layer is equal to or smaller than the upper limit of the above range, the production process is excellent in terms of appearance stability of the coated surface.

[0182] <Other layers>

[0183] In the present disclosure, the film can have only a substrate and an antistatic layer, and can or can not have other layers. As the other layers, an adhesive layer, a base layer, a gas barrier layer, a colored layer, and the like can be cited. These layers can be used singly or in combination of two or more.

[0184] The layer structure of the film will be exemplified below. Note that the layer structure of the film of the present disclosure is not limited to the following.

[0185] (1) A film having a substrate and an antistatic layer in this order.

[0186] (2) A film having a substrate, an antistatic layer, and an adhesive layer in this order.

[0187] (3) A film of any one of the above (1) and (2) further having a gas barrier layer, a colored layer, or the like at any position closer to the antistatic layer than to the substrate.

[0188] <Adhesive layer>

[0189] The film can further have an adhesive layer. The adhesive layer is a layer having adhesiveness to other members. The material of the adhesive layer is not particularly limited. In one embodiment, the adhesive layer can include a reaction cured product of a hydroxyl group-containing (meth)acrylic polymer and a polyfunctional isocyanate compound. In this case, the hydroxyl group-containing (meth)acrylic polymer is crosslinked to the reaction cured product by reacting with the polyfunctional isocyanate compound. The adhesive layer can be a reaction cured product of a hydroxyl group-containing (meth)acrylic polymer, a polyfunctional isocyanate compound, and other components.

[0190] The hydroxyl group-containing (meth)acrylic polymer can be a copolymer having at least a hydroxyl group-containing (meth)acrylate unit and a unit different from the hydroxyl group-containing (meth)acrylate unit.

[0191] As the monomer forming the hydroxyl group-containing (meth)acrylate unit, (meth)acrylic acid 2-hydroxyethyl ester, (meth)acrylic acid 2-hydroxypropyl ester, (meth)acrylic acid 4-hydroxybutyl ester, 1,4-cyclohexanedimethanol monoacrylate, 2-acryloyloxyethyl-2-hydroxyethyl-o-phthalate, and the like can be cited. The monomer forming the hydroxyl group-containing (meth)acrylate unit can be used singly or in combination of two or more.

[0192] Monomers that form units different from those containing hydroxyl (meth)acrylate units include (meth)acrylates without hydroxyl groups, (meth)acrylic acid, acrylonitrile, and macromonomers with unsaturated double bonds.

[0193] Examples of (meth)acrylates without hydroxyl groups include: alkyl (meth)acrylates, cyclohexyl (meth)acrylate, phenyl (meth)acrylate, toluene (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, glycidyl (meth)acrylate, 2-aminoethyl (meth)acrylate, 3-(methacryloyloxypropyl)trimethoxysilane, trifluoromethyl (meth)acrylate, and so on. 2-Trifluoromethylethyl acrylate, 2-Perfluoroethyl acrylate, 2-Perfluoroethyl-2-Perfluorobutyl acrylate, 2-Perfluoroethyl acrylate, 2-Perfluoromethyl acrylate, 2-Perfluoromethyl acrylate, 2-Perfluoroethyl acrylate, 2-Perfluorohexyl ethyl acrylate, 2-Perfluorodecyl ethyl acrylate, 2-Perfluorohexadecyl acrylate, etc.

[0194] As alkyl esters of (meth)acrylate, compounds in which the alkyl group has 1 to 12 carbon atoms are preferred, such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, n-pentyl methacrylate, n-hexyl methacrylate, n-heptyl methacrylate, n-octyl methacrylate, nonyl methacrylate, decyl methacrylate, and dodecyl methacrylate.

[0195] Examples of macromonomers with unsaturated double bonds include (meth)acrylates of polyethylene glycol monoalkyl ethers and other macromonomers with polyoxyalkylene chains.

[0196] The hydroxyl groups in hydroxyl-containing (meth)acrylic acid polymers are cross-linking functional groups that react with the isocyanate groups in polyfunctional isocyanate compounds.

[0197] The hydroxyl value of the hydroxyl-containing (meth)acrylic acid polymer is preferably 1–100 mg KOH / g, more preferably 29–100 mg KOH / g. The hydroxyl value is determined by the method specified in JIS K0070:1992.

[0198] Hydroxyl (meth)acrylic acid polymers may or may not have carboxyl groups. Like hydroxyl groups, carboxyl groups are cross-linking functional groups that react with isocyanate groups in polyfunctional isocyanate compounds.

[0199] The acid value of the hydroxyl group-containing (meth)acrylic polymer is preferably 0 to 100 mgKOH / g, more preferably 0 to 30 mgKOH / g. The acid value is measured in the same manner as the hydroxyl value by the method prescribed in JIS K0070:1992.

[0200] The polyfunctional isocyanate compound is a compound having 2 or more isocyanate groups, and is preferably a compound having 3 to 10 isocyanate groups.

[0201] As the polyfunctional isocyanate compound, hexamethylene diisocyanate (HDI), toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate (NDI), dimethyl diphenyl diisocyanate (TODI), isophorone diisocyanate (IPDI), xylylene diisocyanate (XDI), triphenylmethane triisocyanate, thiophosphoric acid triphenyl isocyanate, and the like can be exemplified. In addition, isocyanurate bodies (trimers) of these polyfunctional isocyanate compounds and biuret bodies, adducts of these polyfunctional isocyanate compounds and polyol compounds, and the like can be exemplified.

[0202] The polyfunctional isocyanate compound having an isocyanurate ring is preferable from the viewpoint that the reaction-cured product (adhesive layer) exhibits a high elastic modulus due to the planarity of the ring structure.

[0203] As the polyfunctional isocyanate compound having an isocyanurate ring, isocyanurate bodies of HDI (isocyanurate type HDI), isocyanurate bodies of TDI (isocyanurate type TDI), isocyanurate bodies of MDI (isocyanurate type MDI), and the like can be exemplified.

[0204] In the case where the adhesive layer is a reaction-cured product of the adhesive layer composition containing the hydroxyl group-containing acrylic polymer and the polyfunctional isocyanate compound, it is preferable to set the content of the hydroxyl group-containing acrylic polymer and the polyfunctional isocyanate compound in the adhesive layer composition so that the ratio of M COOH / (M NCO ) is 0 to 1.0, and the ratio of M OH / (M NCO + M COOH ) is 0.4 to 3.5. Here, M OH is the number of moles of the hydroxyl groups derived from the hydroxyl group-containing acrylic polymer, M OH is the number of moles of the carboxyl groups derived from the hydroxyl group-containing acrylic polymer, and M COOH is the number of moles of the isocyanate groups derived from the polyfunctional isocyanate compound.

[0205] M NCO / (M COOH + M NCO- M OH ) is preferably 0 to 1.0, more preferably 0 to 0.5. M COOH / (M NCO - M OH ) is above the lower limit value of the above range, adhesion to the member to be contacted is excellent. M COOH / (M NCO - M OH ) is below the upper limit value of the above range, free carboxyl groups remaining in the adhesive layer are less and thus peeling from the member to be contacted is excellent.

[0206] M NCO / (M COOH + M OH ) is preferably 0.4 to 3.5, more preferably 0.4 to 3.0. M NCO / (M COOH + M OH ) is above the lower limit value of the above range, crosslinking density of the adhesive layer, and further, elastic modulus are high, and releasability and peeling from the member to be contacted are excellent. M NCO / (M COOH + M OH ) is below the upper limit value of the above range, elastic modulus of the adhesive layer does not become too high, and adhesion to the member to be contacted is excellent.

[0207] The total content of the hydroxyl-containing acrylic polymer and the polyfunctional isocyanate compound in the adhesive layer composition is preferably 50% by mass or more relative to the total amount of the adhesive layer composition.

[0208] The adhesive layer can contain a crosslinking catalyst (amine-based, metal compound, acid, etc.), a reinforcing filler, a coloring dye, a pigment, an antistatic agent, and the like.

[0209] The thickness of the adhesive layer is preferably 0.05 to 3.0 μm, more preferably 0.05 to 2.5 μm, and further preferably 0.05 to 2.0 μm. The thickness of the adhesive layer is above the lower limit value of the above range, and releasability is excellent. The thickness of the adhesive layer is below the upper limit value of the above range, and coating stability is excellent. In addition, the thickness of the adhesive layer is below the upper limit value of the above range, and the tackiness after coating does not become too strong, and a continuous coating process becomes easy.

[0210] As one preferred example of the adhesive layer, the adhesive layer described in International Publication No. 2016 / 125796 can be cited.

[0211] [Method for manufacturing a film]

[0212] The film can be produced, for example, by applying a coating liquid for the antistatic layer to one face of the substrate and drying. Further, a desired layer other than the antistatic layer, such as an adhesive layer, a base layer, etc. can be further formed by coating. Heating can be performed in the formation of each layer to promote curing.

[0213] In one embodiment, the method for producing a film includes: subjecting a surface of a substrate to plasma treatment, and providing an antistatic layer on the substrate subjected to the plasma treatment or providing the antistatic layer on the substrate subjected to the plasma treatment at least through a third layer adjacent to the substrate, in a surface chemical composition analysis of the substrate subjected to the plasma treatment by XPS, O / C is in the range of 0.010 to 0.200, or N / F is in the range of 0.010 to 0.100, or both. In this embodiment, an adhesive layer can be further provided on a face of the antistatic layer opposite to the substrate.

[0214] Further, the plasma treatment can be performed in the presence of argon gas; ammonia gas; or nitrogen gas mixed with or not mixed with 10% by volume or less of hydrogen.

[0215] Further, the method for producing a film can further include subjecting the surface of the substrate to corona treatment on the basis of the plasma treatment, and can further include subjecting the surface of the substrate to corona treatment before the plasma treatment.

[0216] Details of the plasma treatment and the corona treatment in this embodiment are as described above.

[0217] [Properties of the film]

[0218] (Tackiness of the antistatic layer)

[0219] The antistatic layer of the film of the present disclosure has excellent tackiness, and as a result, excellent antistatic properties can be obtained. In one embodiment, the following tape peeling test is used as an index of the tackiness:

[0220] After uniaxial stretching by 300% at 25°C, Cellotape (registered trademark) is pressure-bonded to the surface of the antistatic layer side of the film with a roll at a load of 4 kg, and the Cellotape (registered trademark) is peeled off in the direction of 180° with respect to the film at a speed of 100 m / minute within 5 minutes, to obtain the proportion of the peeling area of the film with respect to the area of the adhesive portion of the Cellotape (registered trademark). The tape peeling test can be specifically performed by the method described in the examples.

[0221] The proportion of the peeling area is preferably less than 5%, more preferably 4% or less, further preferably 3% or less, and can also be 0%. In the first embodiment of the present disclosure, the proportion of the peeling area is less than 5%.

[0222] The stretching speed of the uniaxial stretching is not particularly limited. The uniaxial stretching can be performed at a constant load or at a constant speed. In the case of the constant speed, when the initial length of the stretched portion is set to Lm, the stretching is preferably performed at a speed in the range of 0.0005 x Lm / minute to 10 x Lm / minute, and more preferably in the range of 0.001 x Lm / minute to 10 x Lm / minute. In the case of the constant load, the stretching can be performed to 300% by the method of fixing one side of a rectangular film to the upper portion and suspending a weight or the like on the other side to the extent not exceeding the breaking strength, that is, by the creep deformation. In the case where a phenomenon such as breaking occurs when the film is uniaxially stretched, the stretching conditions are explored to stretch to 300%.

[0223] In another embodiment, the following wiping test is used as an index of adhesiveness. The wiping test is a test performed under more severe conditions than the tape peeling test, but is not any limitation on the embodiments of the present disclosure.

[0224] After uniaxial stretching to 300% at 25°C, the film is wiped by rubbing the surface of the antistatic layer side of the film with a nonwoven fabric (e.g., BEMCOT (registered trademark)) to which acetone is attached back and forth 20 times with a load of 4 kg, and the haze before and after the wiping is measured at the same portion of the film. The haze before the wiping is set to H1, and the haze after the wiping is set to H2. By satisfying the formula (H2 - H1) ≥ 0, it is possible to determine that peeling does not occur after the wiping and that the adhesiveness is good. The wiping test can be specifically performed by the method described in the examples. In the second embodiment of the present disclosure, the formula (H2 - H1) ≥ 0 is satisfied. It is preferable that the formula (H2 - H1) ≥ 1 is satisfied, and it is more preferable that the formula (H2 - H1) ≥ 3 is satisfied. The upper limit value of the formula (H2 - H1) is not particularly limited, but from the viewpoint of avoiding erroneous evaluation due to accidental film scratches, it is preferable that the evaluation is performed in the range satisfying the formula (H2 - H1) ≤ 40, and it is more preferable that the formula (H2 - H1) ≤ 30 is satisfied.

[0225] The conditions of the uniaxial stretching can be applied to the same conditions as the tape peeling test.

[0226] (Tensile strength)

[0227] The tensile strength of the film is preferably 35 MPa or more, more preferably 40 MPa or more, further preferably 45 MPa or more, and particularly preferably 50 MPa or more. The tensile strength of the film is not particularly limited and is preferably as large as possible.

[0228] The tensile strength of the film is measured in accordance with JIS K 7127:1999. The measurement is specifically performed by the method described in the examples.

[0229] (Surface resistance value)

[0230] The surface resistance value of the film is not particularly limited and can be 10 17 Ω / □ or less, preferably 10 11 Ω / □ or less, more preferably 10 10 Ω / □ or less, further preferably 10 9 Ω / □ or less. The lower limit of the surface resistance value is not particularly limited.

[0231] The surface resistance value is measured according to IEC 60093:1980: Ring Method with an applied voltage of 500 V for 1 minute. As a measuring device, for example, an ultra-high resistance meter R8340 (Advantec Corporation) can be used.

[0232] [Use of the film]

[0233] The use of the film of the present disclosure is not particularly limited. For example, the film of the present disclosure can be used as a release film used in a process of sealing a semiconductor element with a curable resin. In addition, the film of the present disclosure has excellent antistatic properties even when stretched, and thus can be used as a release film used in a process of producing a sealing body in which a part of a semiconductor package, for example, an electronic component, is exposed from a sealing resin having a complex shape.

[0234] [Method for manufacturing a semiconductor package]

[0235] In one embodiment, the method for manufacturing a semiconductor package includes disposing the film of the present disclosure on an inner surface of a mold, disposing a substrate provided with a semiconductor element in the mold with the film disposed therein, sealing the semiconductor element in the mold with a curable resin to produce a sealing body, and releasing the sealing body from the mold.

[0236] As the semiconductor package, integrated circuits in which a transistor, a diode, or the like is integrated, light emitting diodes having a light emitting element, and the like can be exemplified.

[0237] As the package shape of the integrated circuit, the entire integrated circuit can be covered, or a part of the integrated circuit, that is, a part of the integrated circuit is exposed, can be covered. As specific examples, a BGA (Ball Grid Array), a QFN (Quad Flat Non-leaded package), and a SON (Small Outline Non-leaded package) can be exemplified.

[0238] As the semiconductor package, from the viewpoint of productivity, it is preferable to be manufactured by bulk sealing and individual sealing, and as the sealing method, for example, an integrated circuit of a MAP (Moldied Array Packaging) method or a WL (Wafer Level packaging) method can be cited.

[0239] As the curable resin, a thermosetting resin such as an epoxy resin, a silicone resin, or the like is preferable, and an epoxy resin is more preferable.

[0240] In one embodiment, the semiconductor package can have electronic components such as a source electrode, a sealing glass, or the like in addition to the semiconductor element, or can not have these components. In addition, a part of the semiconductor element, the source electrode, the sealing glass, or the like can be exposed from the resin.

[0241] The manufacturing method of the semiconductor package can employ a publicly known manufacturing method in addition to the use of the film of the present disclosure. For example, as the sealing method of the semiconductor element, a transfer molding method can be cited, and as the device used at this time, a publicly known transfer molding device can be used. The manufacturing conditions can also be the same conditions as those in the publicly known manufacturing method of the semiconductor package.

[0242] Example

[0243] The embodiments of the present disclosure will be specifically described below by examples, but the embodiments of the present disclosure are not limited to these examples. In the following examples, Examples 1 to 6, 13 to 15, and 18 to 23 are examples, and Examples 7 to 12, 16, and 17 are comparative examples.

[0244] The materials used to form each layer are as follows.

[0245] -Substrate-

[0246] • ETFE film 1: Fluon (registered trademark) ETFE LM720AXP (manufactured by AGC Inc.) was fed to an extruder having a T-shaped die, and stretched between a crimping roller having a surface with unevenness and a mirror-finished metal roller to produce a film having a thickness of 50 μm. The temperature of the extruder and the T-shaped die was 300°C, and the temperature of the crimping roller and the metal roller was 90°C. The surface of the obtained film had an Ra of 2.2 μm on the crimping roller side and 0.1 μm on the mirror side.

[0247] -Antistatic layer coating liquid-

[0248] • Antistatic agent-containing material 1: ARACOAT (registered trademark) AS601D (manufactured by Arakawa Chemical Industries, Ltd.), solid content 3.4 mass%, conductive polythiophene 0.4 mass%, acrylic resin 3.0 mass%

[0249] • Curing agent 1: ARACOAT (registered trademark) CL910 (manufactured by Arakawa Chemical Industries, Ltd.), solid content 10 mass%, polyfunctional aziridine compound

[0250] Coating liquid for adhesive layer

[0251] • (Meth)acrylic polymer 1: NIssetsu (registered trademark) KP2562 (manufactured by Nippon Carbonic Industries, Ltd.), containing hydroxyl group, not containing carboxyl group

[0252] • Polyfunctional isocyanate compound 1: NIssetsu CK157 (manufactured by Nippon Carbonic Industries, Ltd.), solid content 100%, isocyanurate type hexamethylene diisocyanate, NCO content 21 mass%

[0253] • Catalyst dilution solution 1: NIssetsu CK-920 (manufactured by Nippon Carbonic Industries, Ltd.), acetylacetone dilution of dioctyl dilaurate, tin content 0.05%

[0254] A film was produced in accordance with the following procedure.

[0255] (Pretreatment of substrate)

[0256] In the respective examples described in Tables 1 and 2, the ETFE film surface was subjected to plasma treatment and, as necessary, corona treatment, under the conditions described in Tables 1 and 2.

[0257] [Measurement of O / C and N / F]

[0258] As necessary, the substrate subjected to the above pretreatment was subjected to analysis of O / C and N / F by XPS. The analysis target of XPS was a depth of 2 to 8 nm from the surface of the substrate. The information of the analysis device and the analysis conditions are as follows.

[0259] Analysis device: Quantera PHI manufactured by Ulvac-Phi, Inc.

[0260] X-ray source: Al Kα 14 kv

[0261] Beam diameter: 100 μm Φ

[0262] Measurement field: 800 x 300 μm 2

[0263] Measurement mode: Narrow spectrum measurement

[0264] Measurement element and measurement region of binding energy of each element, cumulative number:

[0265] C1s: 278 to 297 eV, cumulative 2 times

[0266] O 1s: 525 to 544 eV, 3 times in total

[0267] N 1s: 392 to 411 eV, 8 times in total

[0268] F 1s: 680 to 699 eV, 1 time in total

[0269] Binding energy: 224.0 eV

[0270] Energy level: 0.4 eV

[0271] Cycles: 8 cycles

[0272] Neutralization gun: used

[0273] Angle of detector to sample surface: 45°

[0274] The object elements of the XPS measurement were C, O, F, and N, and the proportions of F and N in the total (unit: Atomic %) were taken as the amounts of the respective atoms. Then, based on the values of the respective Atomic %, N / F and O / C were calculated.

[0275] [Production of the antistatic layer]

[0276] 100 parts by mass of the antistatic agent-containing material 1 and 10 parts by mass of the curing agent 1 were mixed to prepare an antistatic layer coating liquid having a solid content of 2 mass %. The antistatic layer coating liquid was applied to the surface of the substrate using a gravure coater to form an antistatic layer having a thickness of 0.2 μm after drying. The application was performed in a direct gravure manner using a Φ 100 mm x 250 mm wide lattice 150 # -depth 40 μm roll as a gravure. Drying was performed at 55°C for 1 minute by roll support in a drying oven at an air volume of 19 m / sec.

[0277] [Production of the adhesive layer]

[0278] 100 parts by mass of the (meth)acrylic polymer 1, 6 parts by mass of the polyfunctional isocyanate compound 1, 21 parts by mass of the catalyst dilution solution 1, and ethyl acetate were mixed to prepare an adhesive layer coating liquid. The amount of ethyl acetate was adjusted so that the solid content of the adhesive layer coating liquid was 14 mass %.

[0279] The adhesive layer coating liquid was applied to the surface of the antistatic layer using a gravure coater, and an adhesive layer having a thickness of 0.8 μm was formed after drying. The application was performed in a direct gravure manner using a Φ 100 mm x 250 mm wide lattice 150 # -depth 40 μm roll as a gravure. Drying was performed at 65°C for 1 minute by roll support in a drying oven at an air volume of 19 m / sec. Subsequently, curing was performed at 40°C for 48 hours to obtain a film.

[0280] [Tape peeling test]

[0281] The film was cut into a shape of 150 mm in length and 50 mm in width with the film- forming direction (MD) as the long side. Then, a preliminary deformation applying operation was performed using a universal testing machine (autograph AGC-X manufactured by Shimadzu Corporation). First, a jig was installed to hold a sample of 50 mm in width, the jig interval was set to 50 mm, both sides of the film cut previously were held equally with the jig, and were installed in a manner that no wrinkles were generated. Then, a uniaxial tensile strain (i.e., 300% of stretching) was applied to the film by moving a chuck by a displacement of 150 mm at a speed of 50 mm / minute in an environment of 25°C. Within 10 seconds after the stretching, the chuck was removed, and the sample was left for 15 minutes.

[0282] Nichiban Cellotape (registered trademark) CT-18 (18 mm in width) was attached to the straight back in a length of 70 mm along the uniaxial direction stretched previously, and a plastic roller of 35 mm in diameter and 40 mm in width was pressed against the tape with a strength of 4 kg load to and fro 5 times. Then, the end of the attached tape was peeled off at a speed of 100 m / minute along a direction of 180° with respect to the film within 5 minutes. The time required for the peeling was about 0.4 seconds.

[0283] Thereafter, it was visually evaluated whether or not there were adherents on the tape-adhering surface, and whether or not there was a coating film peeling on the film side. It was "peeling" when 5% or more of the area of the film surface had a peeling defect, and it was "no peeling" when the peeling defect was less than 5%.

[0284] [Scrubbing test]

[0285] The film was cut into a shape of 150 mm in length and 50 mm in width with the film- forming direction (MD) as the long side. Then, a preliminary deformation applying operation was performed using a universal testing machine (autograph AGC-X manufactured by Shimadzu Corporation). First, a jig was installed to hold a sample of 50 mm in width, the jig interval was set to 50 mm, both sides of the film cut previously were held equally with the jig, and were installed in a manner that no wrinkles were generated. Then, a uniaxial tensile strain (i.e., 300% of stretching) was applied to the film by moving a chuck by a displacement of 150 mm at a speed of 50 mm / minute in an environment of 25°C. Within 10 seconds after the stretching, the chuck was removed, and the sample was left for 15 minutes.

[0286] Then, the haze of the site to which the tensile strain was applied was measured optically. The haze Hl of the stretched part was found using a haze meter NDH5000 manufactured by Nippon Denshoku Industries Co., Ltd.

[0287] Subsequently, BEMCOT (registered trademark) M-3II (1 sheet, 1.6 g, 23 cm x 24 cm, weight per unit area 28.9 g / m2) of Asahi Kasei Corporation was folded into 4 folds, and 10 g of acetone was impregnated therein, and while pressing the acetone-impregnated nonwoven fabric with one finger with a load of 4 kg, the nonwoven fabric was rubbed 20 times on the coated surface of the film. Then, after allowing the acetone adhered to the film to dry at 25°C for 15 minutes, the haze of the same part as that measured before wiping was measured, and the haze H2 was calculated. 2

[0288] In the case where the change in haze satisfies (H2 - H1) > 0, the coating film is sufficiently remained on the surface of the substrate, and it is determined as "no peeling". In the case where the change in haze satisfies (H2 - H1) < 0, it is determined as "peeling".

[0289]

[0290] Based on the results of the tape peeling test and the wiping test, the adhesion of the coating film of the film produced in each example was rated as follows.

[0291] A: No peeling was observed in both the tape peeling test and the wiping test.

[0292] B: No peeling was observed in the tape peeling test, but peeling was observed in the wiping test.

[0293] C: Peeling was observed in both the tape peeling test and the wiping test.

[0294]

[0295] A semiconductor element of 5 mm x 5 mm x 200 μm thick fixed on a copper lead frame of 70 mm x 230 mm was sealed with a sealing device (transfer molding device G-LINE Manual System, manufactured by Apic Yamada). As the sealing resin, an epoxy resin composition described later was used. Before the sealing process, a roll of a film of 190 mm in width was set in an upper mold of 250 μm in depth in a roll-to-roll manner. After the lead frame on which the semiconductor element was fixed was disposed in a lower mold, the film was vacuum-adsorbed in the upper mold, the mold was closed, and a curable resin was flowed in. After being pressurized at 175°C for 5 minutes, the mold was opened, and the sealed body was taken out.

[0296] An epoxy resin composition was obtained by pulverizing and mixing the following components with a super mixer for 5 minutes. The cured product of the epoxy resin composition had a glass transition temperature of 135°C, a storage modulus at 130°C of 6 GPa, and a storage modulus at 180°C of 1 GPa.

[0297] ​​​• 8 parts by mass of a phenol aralkyl type epoxy resin containing a phenylene skeleton (softening point 58°C, epoxy equivalent 277 g / eq)

[0298] • 2 parts by mass of a bisphenol A type epoxy resin (melting point 45°C, epoxy equivalent 172 g / eq)

[0299] • 2 parts by mass of a phenol aralkyl resin containing a phenylene skeleton (softening point 65°C, hydroxyl equivalent 165 g / eq)

[0300] • 2 parts by mass of a phenol novolak resin (softening point 80°C, hydroxyl equivalent 105 g / eq)

[0301] • 0.2 parts by mass of a curing accelerator (triphenylphosphine)

[0302] • 84 parts by mass of an inorganic filler (fused spherical silica with a median particle diameter of 16 μm)

[0303] • 0.1 parts by mass of carnauba wax

[0304] • 0.3 parts by mass of carbon black

[0305] • 0.2 parts by mass of a coupling agent (3-glycidoxypropyltrimethoxysilane)

[0306] A low-speed voltage rise test was performed using a ball-plane electrode described in JIS K6911:2006, with the ball electrode brought into contact with the sealed semiconductor element existing portion, and a voltage resistance test was performed at a voltage rise rate of 100 V / S. The test was performed in the atmosphere. The ball was a 6 mm Φ cylinder and the flat plate was a 6 mm Φ cylinder. The voltage resistance test was performed using a 100 kV insulation breakdown test device YST-243-100RHO (YAMA YO tester).

[0307] Cases in which the voltage resistance was 1.0 kV or more were judged to be good (A), and cases in which the voltage resistance was less than 1.0 kV were judged to be poor (C).

[0308] 〔Measurement of tensile strength〕

[0309] A tensile test was performed at 25°C using a V-shaped dumbbell according to JIS K7127:1999, at a chuck speed of 100 mm / minute. The breaking force at this time was measured, and converted to stress based on the initial sample cross-sectional area.

[0310] [Table 1]

[0311]

[0312] [Table 2]

[0313]

[0314] In Tables 1 and 2, the value in parentheses in “treatment environment” in “plasma treatment conditions of the substrate” indicates the H2concentration (vol%) in the N2 / H2mixed gas.

[0315] As can be seen, in Examples 1 to 6, 13 to 15, and 18 to 23 in which no peeling was observed in the tape peeling test, the voltage resistance performance was excellent. Among these, in Examples 1 to 6 and 18 to 23 in which no peeling was observed in the wiping test as well, particularly excellent voltage resistance could be obtained.

[0316] In addition, in Examples 1 to 6, 13 to 15, and 18 to 23 in which O / C was in the range of 0.010 to 0.200, or N / F was in the range of 0.010 to 0.100, or both, the voltage resistance performance was excellent.

[0317] Comparing Example 1 and Example 5, there was a tendency that the tensile strength of the film was improved by the corona treatment before the plasma treatment. In addition, even in the case where the strength of the plasma treatment was increased in Example 6, a good tensile strength could be maintained by performing the corona treatment in advance.

[0318] The disclosure of Japanese Patent Application No. 2021-028909 is incorporated herein by reference in its entirety.

[0319] All of the literature, patent applications and technical standards cited in the present specification are incorporated by reference herein to the same extent as if each individual document, patent application or technical standard were specifically and individually incorporated by reference.

[0320] Explanation of Symbols

[0321] 1 Film

[0322] 2 Substrate

[0323] 3 Antistatic Layer

Claims

1. A membrane, characterized in that, It has at least a substrate and an antistatic layer. The surface of the substrate is treated with plasma. An antistatic layer is provided on the plasma-treated substrate. In the surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, the O / C ratio was in the range of 0.010 to 0.200 or the N / F ratio was in the range of 0.010 to 0.

100. After being stretched 300% uniaxially at 25°C, the peel area ratio during the tape peel test under the following conditions is less than 5%: The registered trademark Cellotape is applied back and forth with a 4 kg load five times on the surface of the antistatic layer side of the film using a roller. Within 5 minutes, the registered trademark Cellotape is peeled off along a direction of 180° relative to the film at a speed of 100 m / min, and the ratio of the peeled area of ​​the film to the area of ​​the bonded portion of the registered trademark Cellotape is obtained.

2. The membrane as claimed in claim 1, wherein, When subjected to a 300% uniaxial stretch at 25°C and then subjected to a wiping test under the following conditions, the equation (H2-H1)≥0 must be satisfied: The membrane was wiped by rubbing the surface of the antistatic layer side of the membrane back and forth 20 times with a non-woven fabric coated with acetone under a load of 4 kg. The haze before and after wiping was measured at the same part of the membrane. The haze before wiping was set as H1 and the haze after wiping was set as H2.

3. A membrane, characterized in that, It has at least a substrate and an antistatic layer. The surface of the substrate is treated with plasma. An antistatic layer is provided on the plasma-treated substrate. In the surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, the O / C ratio was in the range of 0.010 to 0.200 or the N / F ratio was in the range of 0.010 to 0.

100. When subjected to a 300% uniaxial stretch at 25°C and then subjected to a wiping test under the following conditions, the equation (H2-H1)≥0 must be satisfied: The membrane was wiped by rubbing the surface of the antistatic layer side of the membrane back and forth 20 times with a non-woven fabric coated with acetone under a load of 4 kg. The haze before and after wiping was measured at the same part of the membrane. The haze before wiping was set as H1 and the haze after wiping was set as H2.

4. A membrane, characterized in that, It has at least a substrate and an antistatic layer. The surface of the substrate is treated with plasma. An antistatic layer is provided on the plasma-treated substrate. In the surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, the O / C ratio is in the range of 0.010 to 0.

200.

5. The membrane as claimed in claim 4, wherein, In the surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, the N / F ratio is in the range of 0.010 to 0.

100.

6. A membrane, characterized in that, It has at least a substrate and an antistatic layer. The surface of the substrate is treated with plasma. An antistatic layer is provided on the plasma-treated substrate. In the surface chemical composition analysis of the antistatic layer side of the substrate by X-ray photoelectron spectroscopy, the N / F ratio is in the range of 0.010 to 0.

100.

7. The membrane according to any one of claims 1 to 6, wherein, The substrate comprises at least one selected from fluoropolymers, polymethylpentene, syndiotactic polystyrene, and polycyclic olefins.

8. The membrane according to any one of claims 1 to 6, wherein, The substrate comprises at least one selected from ethylene-tetrafluoroethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoro(alkyl vinyl ether) copolymer, and tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride copolymer.

9. The membrane according to any one of claims 1 to 6, wherein the antistatic layer further comprises an adhesive layer on the side opposite to the substrate.

10. The film according to any one of claims 1 to 6, wherein it is a release film used in the process of sealing a semiconductor element with a curable resin.

11. A method for manufacturing a membrane, characterized in that, include: Plasma treatment of the substrate surface, and An antistatic layer is formed on the plasma-treated substrate. In the surface chemical composition analysis of the antistatic layer side of the substrate after plasma treatment by X-ray photoelectron spectroscopy, the O / C ratio is in the range of 0.010 to 0.200, or the N / F ratio is in the range of 0.010 to 0.100, or both.

12. The method for manufacturing a membrane as described in claim 11, wherein, The plasma treatment is carried out in the presence of argon, ammonia, or nitrogen containing less than 10% by volume of hydrogen or containing no hydrogen.

13. The method of manufacturing a membrane as claimed in claim 11 or 12, further comprising subjecting the surface of the substrate to corona treatment prior to the plasma treatment.

14. The method of manufacturing a membrane as claimed in claim 11, further comprising providing an adhesive layer on the surface of the antistatic layer opposite to the substrate.

15. A method for manufacturing a semiconductor package, characterized in that, include: The membrane according to any one of claims 1 to 10, or the membrane manufactured by the manufacturing method according to any one of claims 11 to 14, is disposed on the inner surface of the mold. A substrate containing semiconductor elements is disposed within the mold in which the membrane is disposed. The semiconductor element within the mold is sealed with a curable resin to create a seal. The sealing body is then demolded from the mold.

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