TWI764114B - Tape for electronic parts and processing method of electronic parts - Google Patents

Abstract

The present invention relates to a tape for electronic parts and a processing method for electronic parts, which provides: for a semiconductor wafer with bumps having a large height, the tape for electronic parts and a processing method for electronic parts can be sufficiently adapted in a short time. It is characterized in that there is at least one resin layer (3), and the resin layer (3) uses a nano-indenter, and the depth of the indenter at any temperature of 60°C to 80°C measured in accordance with ISO14577 is: 10000nm～50000nm, and the thickness of the resin layer (3) is 50μm～300μm, and the total thickness is 450μm or less.

Description

Tape for electronic parts and processing method of electronic parts

The present invention relates to a tape for electronic parts and a processing method of the electronic parts. More specifically, it relates to a tape for electronic parts, which is mainly applicable to thin-film grinding processes of semiconductor wafers, and a method for processing electronic parts using the tape for electronic parts.

In the manufacturing process of semiconductor wafers, the semiconductor wafers after patterning are usually subjected to backside grinding, etching and other processes to reduce the thickness of the semiconductor wafers. At this time, for the purpose of protecting the pattern on the surface of the semiconductor wafer, a tape for protecting the surface of the semiconductor wafer is attached to the pattern surface. Generally speaking, the adhesive tape for semiconductor wafer surface protection is formed by laminating an adhesive layer on a base film, and then the adhesive layer is attached to the back surface of the semiconductor wafer and used (for example, refer to Patent Document 1).

In recent years, with the miniaturization and high function of mobile phones and personal computers, wire bonding, which can be mounted in a space-saving manner, is developed compared with the conventional semiconductor chip connection method. In flip chip mounting, when the surface of the semiconductor wafer and the substrate are electrically connected, the connection is made through spherical or cylindrical bumps formed on the surface of the semiconductor wafer. In the past, bumps with a height (thickness) of 100 μm or less have been the mainstream, but in order to ensure the reliability of bonding due to the demand for further miniaturization of semiconductor wafers, bumps with a height (thickness) exceeding 200 μm have been proposed. WLCSP (Wafer level Chip Size Package) for rewiring, etc.

In the case of performing the above-mentioned backside grinding of the wafer using the conventional tape for semiconductor wafer surface protection, the tape system for semiconductor wafer surface protection cannot be sufficiently adhered to the wafer surface due to the height of the bumps. In this way, from the gap between the tape for semiconductor wafer surface protection and the wafer, the cutting water and silicon chips that are sprayed during grinding penetrate into the gap, which contaminates the wafer surface, a phenomenon called leakage.

Therefore, in order to make the tape for semiconductor wafer surface protection conform to the unevenness of the semiconductor wafer surface, it is proposed to provide an intermediate layer with a storage modulus of 1×10 ⁴ to 1×10 ⁶ Pa between the base film and the adhesive layer A tape for protecting the surface of a semiconductor wafer (for example, refer to Patent Document 2). In addition, a tape for protecting the surface of a semiconductor wafer in which a thermoplastic resin intermediate layer having a JIS-A hardness of 10 to 55 and a thickness of 25 to 400 μm is provided between the base film and the adhesive layer (for example, refer to Patent Documents 3, 4). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2000-8010 [Patent Document 2] Japanese Patent Laid-Open No. 2014-17336 [Patent Document 3] Japanese Patent No. 4054113 [Patent Document 4] Japanese Patent No. 3773358

[The problem to be solved by the invention]

However, in the tape for protecting the surface of a semiconductor wafer described in the above-mentioned patent document, the tape for protecting the surface of the semiconductor wafer is made to conform to the unevenness of the surface of the semiconductor wafer. When rounding, the tape for protecting the surface of the semiconductor wafer must be heated and softened, and there is a problem that it takes time for lamination. means of solving problems

Therefore, an object of the present invention is to provide a tape for electronic parts and a processing method for electronic parts which can sufficiently conform to a semiconductor wafer having high bumps in a short time.

In order to solve the above problems, the adhesive tape for electronic parts according to the present invention is characterized by having at least one resin layer, and the resin layer is measured at any temperature between 60°C and 80°C according to ISO14577 using a nano-indenter. In one temperature, the pressing depth of the indenter of the nano-indenter is 10,000 nm to 50,000 nm, and the thickness of the resin layer is 50 μm to 300 μm, with a total thickness of 450 μm or less.

In addition, it is preferable that the said adhesive tape for electronic components is one whose thermal conductivity at 60-80 degreeC of the said resin layer is at least 0.30 W/m･K or more.

It is preferable that the said tape for electronic components is bonded to the circuit formation surface of the semiconductor wafer provided with the level difference of 10 micrometers or more.

As for the said adhesive tape for electronic components, it is preferable that the thickness of the said resin layer is 1 time or more and 2 times or less of the said level difference.

In addition, in order to solve the above-mentioned problems, the method for processing electronic components according to the present invention is characterized by having: bonding at a temperature of 50 to 100° C. on a circuit formation surface of a semiconductor wafer provided with a step difference of 10 μm or more. The bonding process of the above-mentioned tape for electronic components, and the grinding process of grinding the surface opposite to the circuit formation surface of the semiconductor wafer after the bonding process.

In the above-mentioned processing method of electronic parts, the lamination speed in the lamination process is preferably 3 mm/S or more. Invention effect

For example, the adhesive tape for electronic parts according to the present invention can be sufficiently adapted to a semiconductor wafer having a high bump in a short time.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing the structure of an electronic component adhesive tape 1 according to an embodiment of the present invention.

As shown in FIG. 1, the adhesive tape 1 for electronic components concerning this embodiment has the base film 2, and the resin layer 3 is provided in at least one side of the base film 2. As shown in FIG. The upper surface of the resin layer 3 is provided with an adhesive layer 4, and the upper surface of the adhesive layer 4 is laminated on the release-treated surface of the release film 5, which is a release-treated surface. . However, in the present embodiment, the release film is provided, but the release film 5 is not necessarily provided.

Hereinafter, each component of the adhesive tape 1 for electronic components of this embodiment is demonstrated in detail.

(Substrate film 2) As the base film 2 of the tape 1 for electronic components of the present invention, known plastics, rubbers, and the like can be used. For the base film 2, especially when a radiation-curable composition is used for the adhesive layer 4, it is preferable to select a structure with good transmittance of radiation having a wavelength at which the composition is cured. However, here, radiation refers to, for example, a composition of light such as ultraviolet rays, or laser light, or ionizing radiation such as electron beams, and hereinafter, these are collectively referred to as radiation.

Examples of resins that can be selected for the base film 2 include high density polyethylene (HDPE), low density polyethylene (LDPE), polypropylene (PP), ethylene vinyl acetate (EVA), Polyolefins such as ethylene acrylic acid copolymer or ethylene methacrylic acid copolymer and these metal cross-linked bodies (ionomers), or polyethylene terephthalate (PET), polyethylene naphthalate Polyesters such as diester (PEN), polybutylene terephthalate (PBT), or the like, or a film formed by crosslinking acrylic resin. Each resin system may be used alone as a single-layer base material, or a combination of resins may be mixed, or a multi-layer structure of different resins may be used. Moreover, in order to prepare the coloring pigment etc. of the adhesive tape 1 for protecting the semiconductor wafer surface for identification and identification, an additive may be added in a range that does not affect the physical properties.

The base film 2 has a tensile elastic modulus of 0.01-10GPa at 25°C, and more preferably 0.1-5GPa, in order to be used as the adhesive tape 1 for electronic parts or to suppress the warpage of the semiconductor wafer 6 during film grinding. . Furthermore, when the base film 2 is the outermost surface, it is required to be able to withstand processing heat such as the thermal bonding of the tape 1 for electronic parts, or the grinding of the semiconductor wafer 6, and the tape 1 for electronic parts is used. When peeling, in the case of heating and pressing the heat-sealing film on the back of the tape and then peeling off, the melting point is preferably 70-170°C, and more preferably 90-140°C.

The thickness of the base film 2 is not particularly limited, and may be appropriately set, and is preferably 10 to 300 μm, and preferably 25 to 100 μm.

The manufacturing method of the said base film 2 is not specifically limited. Conventional methods such as calendering, T-die extrusion, and blow molding can be used. In addition, it is also possible to use an adhesive or the like as a base film by laminating a film independently formed into a film and another film.

The surface on the resin layer 3 side on which the base film 2 is provided may be suitably treated with corona treatment or a primer layer in order to improve the adhesiveness with the resin layer 3 . However, it is also desirable to roughen the surface on the resin layer 3 side where the base film 2 is not provided, or to coat with a lubricant, and by doing so, the barrier prevention during storage of the tape 1 for electronic parts of the present invention can be obtained. etc. effect.

When the tape 1 for electronic components is peeled off, the heat-sealing film is heated and pressed on the back of the tape and then peeled off. On the surface on the side of the resin layer 3 on which the base film 2 is not provided, a heat-sealing film is provided. An adhesive coating or resin layer is also desirable. The melting point of these heat-sealing layers is preferably 70-170°C, and more preferably 90-140°C. In particular, as the base film 2, a heat seal layer is effective when a high melting point material such as PET is used.

(Resin layer 3) As the resin constituting the resin layer 3, a nano-indenter of the resin layer 3 is used, and the indenter of the nano-indenter at any temperature of 60°C to 80°C measured in accordance with ISO14577 has a pressing depth of 10000 nm to 10,000 nm. The structure of 50000 nm is not particularly limited, and a known resin can be used.

Examples of the resin that can be selected for the resin layer 3 include polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylic acid copolymer, ethylene-acrylic acid methyl copolymer, ethylene-acrylic acid copolymer, ionic A single polymer or copolymer of alpha-olefins such as cross-linked polymers. Each resin system may be used alone as a single layer, or a combination of resins may be mixed, or a multi-layer structure of different resins may be used.

The resin layer 3 uses a nano-indenter, and the indenter of the nano-indenter at any temperature of 60° C. to 80° C. measured in accordance with ISO14577 has a pressing depth of 10,000 nm to 50,000 nm. When the pressing depth of the indenter of the nano-indenter is less than 10,000 nm at any temperature of 60°C to 80°C, it takes time for the tape 1 for electronic parts to fully conform to the unevenness 61 on the surface of the semiconductor wafer 6 .

When the pressing depth of the indenter of the nano-indenter exceeds 50,000 nm at any temperature between 60°C and 80°C, the thickness of the tape 1 for electronic parts deteriorates due to excessive deformation due to heating and lamination. In this case, or when the resin layer 3 is exposed on the side surface of the semiconductor wafer 6 , when the tape 1 for electronic components is cut along the side surface of the semiconductor wafer 6 , burrs or lumps are formed, contaminating the semiconductor wafer 6 . When a burr or the like occurs in the cut portion of the resin layer 3 , when the back surface of the semiconductor wafer 6 is ground or polished, the burr or the like is rolled into the processing surface, causing side edge cracks and breakage of the semiconductor wafer 6 . . In addition, in the case of dry polishing of the semiconductor wafer 6 or the like, the frictional heat through the processing may exceed 60° C., and it is considered that the semiconductor wafer 6 may be damaged or the thickness accuracy may be poor. Furthermore, in the transportation or storage of the tape 1 for electronic components, the high temperature may exceed 60°C, and it is also considered that the end of the tape 1 for electronic components is softened, and the tape 1 for electronic components is used as a In the case of transporting or storing the rolls, misplacement at the end or contamination of the periphery of the softened resin occurs.

The pushing depth of the indenter of the nano-indenter is in accordance with ISO14577-1:2002. Using the nano-indenter, load is applied to the triangular pyramid (Berkovich) indenter formed by the diamond drill of the nano-indenter, plus The depth of the sample surface with a force of 10 mN was zero, and the indenter reached the depth when the indenter was pushed with a force of 50 mN from then on.

The indenter of the resin layer 3 at 60-80° C. is pushed into the indenter, for example, the density of the resin or the case of the comonomer copolymer can be adjusted by the comonomer content ratio. In the case of ethylene-vinyl acetate copolymer, ethylene-methyl acrylate copolymer, and ethylene butyl acrylate, the comonomer content is preferably 10 to 50% by mass, and more preferably 25 to 45%. In the case of α-olefins, the density is preferably 0.87-0.93, and more preferably 0.88-0.90. In addition, it can be adjusted by the molecular weight of the resin, and the weight average molecular weight is preferably 10,000 to 200,000, and more preferably 40,000 to 80,000.

The thermal conductivity of the resin layer 3 at 60°C to 80°C is at least 0.30 W/m·K or more, and more preferably 0.4 W/m·K or more at 70°C. The thermal conductivity was measured in accordance with JIS A1412. In order to set the thermal conductivity at 60 to 80° C. of the resin layer 3 to 0.30 W/m·K or more, in addition to using a resin having such characteristics, a thermally conductive filler may be included. The thermally conductive filler is preferably one or two or more selected from inorganic nitrides, inorganic oxides, and metals. Specific examples include: inorganic nitrides such as aluminum nitride, boron nitride, oxide Inorganic oxides of aluminum, silicon oxide, magnesium oxide, etc., metals such as gold, silver, nickel, aluminum, etc., anti-blocking agent of talc, calcium carbonate, silicon dioxide, etc. Among them, aluminum nitride which exhibits insulating properties and high thermal conductivity is preferable. More desirably, in order to improve the water resistance, the surface-treated aluminum nitride can be mentioned. These systems may be used by mixing one type or two or more types. The content ratio of the filler in the resin layer 3 is preferably 3 to 60 mass %, and more preferably 20 to 50 mass % with respect to the total mass of the resin layer 3 .

The resin layer 3 may contain a stabilizer, a slip agent, an oxidation inhibitor, a pigment, a plasticizer, and the like as necessary. However, depending on the type and content of the additives, the adhesive layer or the semiconductor wafer may be contaminated, and in this case, a barrier layer is preferably provided between the resin layer 3 and the adhesive layer.

The thickness of the resin layer 3 is 50 to 300 μm, preferably 150 to 270 μm. When the thickness of the resin layer 3 is less than 50 μm, it becomes difficult to sufficiently conform the tape 1 for electronic components to the unevenness 61 on the surface of the semiconductor wafer 6 . When the thickness of the resin layer 3 exceeds 300 μm, when the tape 1 for electronic components is thermally bonded to the surface of the semiconductor wafer 6 , the thermal conductivity deteriorates and it takes time to soften the resin layer 3 . It takes time for the component tape 1 to fully conform to the unevenness 61 on the surface of the semiconductor wafer 6 .

In addition, the thickness of the resin layer 3 is preferably not less than 1 time or more than twice the level difference of the surface of the semiconductor wafer 6 and not more than 2 times. When the thickness of the resin layer 3 is less than 1 time the level difference on the surface of the semiconductor wafer 6 , there is a possibility that the tape 1 for electronic components cannot be sufficiently conformed to the unevenness 61 on the surface of the semiconductor wafer 6 . When the thickness of the resin layer 3 exceeds 2 times the level difference of the surface of the semiconductor wafer 6, when the adhesive tape 1 for electronic parts is heated and bonded to the surface of the semiconductor wafer 6, the thermal conductivity is deteriorated, and the resin layer 3 acts as a softening agent. It takes time to make the tape 1 for electronic components conform to the unevenness 61 on the surface of the semiconductor wafer 6 sufficiently.

The method of laminating the resin layer 3 is not particularly limited, but, for example, a method of laminating the base film 2 prepared in advance can be exemplified by extruding the resin layer 3 into a film shape by a T-die extruder. 2. A method of performing dry lamination or thermal lamination by separately forming a film with the base film 3, a method of simultaneously forming a film by co-extrusion of the base film 2 and the resin layer 3, and the like. The co-extrusion method is a blow molding method other than the T-die extrusion method.

(adhesive layer 4) The adhesive composition constituting the adhesive layer 4 is not particularly limited, and conventional structures may be used. base) copolymers of acrylates. Examples of monomer component systems of polymers containing acrylate as constituents include methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, and isobutyl , pentyl, isopentyl, hexyl, heptyl, cyclohexyl, 2-ethylhexyl, octyl, isooctyl, nonyl, isononyl, decyl, isodecyl, undecyl, lauryl , tridecyl, tetradecyl, octadecyl, octadecyl, and dodecyl with a carbon number of 30 or less, ideally a linear or branched alkyl group with a carbon number of 4 to 18 Alkyl acrylate or methacrylate. These alkyl (meth)acrylates may be used alone or in combination of two or more.

The following monomers may be contained as a constituent system in the acrylic resin other than the above. For example, carboxyl groups such as acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, butenedioic acid, and crotonic acid can be mentioned. Containing a single molecule, anhydrous maleic acid, or itaconic anhydride and other acid anhydride single molecules, (meth)acrylic acid 2-hydroxyethyl, (meth)acrylic acid 2-hydroxypropyl, (meth)acrylic acid 4- Hydroxybutyl, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxydodecyl (meth)acrylate, and (4-hydroxymethylcyclohexane) methyl (meth) acrylic acid and other hydroxyl groups contain a single molecule, styrene sulfonic acid, acryl sulfonic acid, 2-(meth) acrylamide-2-methyl propane Sulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylic acid, and (meth)acryloyloxynaphthalenesulfonic acid, etc., the sulfonic acid group contains a single molecule; 2-hydroxyethylpropene The phosphoric acid group such as acylphosphoric acid contains a single molecule, (meth)acrylamide, (meth)acrylic acid N-methylolamide, (meth)acrylic acid alkylamine group (for example, methacrylic acid dimethylamino group) ethyl ester, t-butylaminoethyl methacrylate, etc.), N-vinylpyrrolidone, acryl morpholine, vinyl acetate, styrene, acrylonitrile, etc. These monomer components may be used alone or in combination of two or more.

In addition, the acrylic resin may contain the following polyfunctional monomers as constituent components. Examples thereof include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate (meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, tetramethanol methane tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol Tetra(meth)acrylate, Dipentaerythritol monohydroxy(meth)acrylate, Dipentaerythritol Hex(meth)acrylate, Epoxy(meth)acrylate, Polyester(meth)acrylate, and Amine Ethyl formate (meth)acrylate, etc. These polyfunctional mono-systems may be used alone or in combination of two or more.

Examples of the acrylates include ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, glycidyl acrylate, 2-hydroxyethyl acrylate, and the like. Moreover, the structure which replaced the above-mentioned acrylate, for example with the structure of methacrylate, etc. acrylic polymer and a hardening|curing agent can be used.

As a hardening agent, the hardening agent described in Unexamined-Japanese-Patent No. 2007-146104 can be used. For example, for 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, 1,3-bis(N,N-diglycidylaminomethyl)toluene, 1,3-bis(N,N-diglycidylaminomethyl)toluene, -Bis(N,N-diglycidylaminomethyl)benzene ring, N,N,N,N'-tetraglycidyl-m-m-xylylenediamine, etc. have two or more epoxy groups in the molecule The epoxy compounds, for 2,4-diisocyanate tolyl, 2,6-diisocyanate tolyl, 1,3-xylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane- Isocyanate-based compounds having two or more isocyanate groups in the molecule, such as 4,4'-diisocyanate, for tetramethylol-tri-β-aziridine propionate, trimethylol-tri-β- In the molecule of aziridine propionate, trimethylolpropane-tri-β-aziridine propionate, trimethylolpropane-tri-β-(2-propeneimine) propionate, etc. An aziridine-based compound having two or more aziridine groups, and the like. The content of the hardener may be adjusted according to the desired adhesive force or storage modulus, and is preferably 0.01-10 parts by mass, more preferably 0.1-5 parts by mass, for 100 parts by mass of the polymer.

When the photopolymerizable compound and the photopolymerization initiator are contained in the adhesive layer 4 as described above, the adhesive layer 4 can be cured by being irradiated with ultraviolet rays, and the adhesive force can be reduced. As such a photopolymerizable compound, as disclosed in Japanese Patent Laid-Open No. 60-196956 and Japanese Patent Laid-Open No. 60-223139, in the molecule that can be irradiated with light as a three-dimensional network, at least A low molecular weight compound having two or more photopolymerizable carbon-carbon double bonds.

Specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxyacrylate, dipentaerythritol hexaacrylate, or 1,4 - butanediol diacrylate are applicable , 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate, etc.

As the photopolymerization initiator, the photopolymerization initiators described in JP 2007-146104 or JP 2004-186429 A can be used. Can be used in combination with benzoin isopropyl ether, benzoin isobutyl ether, dimethyl phenone, Michler's ketone, chlorothioxanthone, benzyl methyl ketal, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethyl phenyl Propane etc.

As the adhesive layer 4, a polymer having a photopolymerizable carbon-carbon double bond in a polymer, a photopolymerization initiator, and a photopolymerizable adhesive using a resin composition containing a hardener can be used. As a polymer having a carbon-carbon double bond in the polymer, it is independently polymerized or copolymerized by any method of one or two or more kinds, and the side chain has 4 to 12 carbon atoms, more preferably carbon atoms. A (meth)acrylic polymer of monomers such as (meth)acrylates of alkyl groups of number 8 or copolymerizable modified monomers.

In addition, for the adhesive composition constituting the adhesive layer 4, an adhesion imparting agent, an adhesion adjusting agent, a surfactant, etc., or other modifiers, etc. can be prepared as necessary. In addition, an inorganic compound filler may be appropriately added.

The adhesive layer 4 can be formed, for example, by applying an adhesive composition on the release film 5 , drying it, and transferring it to the resin layer 3 . The thickness of the adhesive layer 4 in the present invention is desirably 1 to 130 μm, more desirably 1 to 40 μm, and still more desirably 1 to 20 μm. The function of the adhesive layer 4 in the present invention is mainly to ensure the adhesion and peelability to the surface of the semiconductor wafer 6 . When the adhesive layer 4 is thick, there is a possibility that compliance with the semiconductor wafer 6 is hindered by its storage modulus, or it may become a cause of residue with respect to the semiconductor wafer 6 .

The total thickness of the adhesive layer 4 and the resin layer 3 is preferably equal to or greater than the height of the unevenness on the surface of the semiconductor wafer 6 . The individual thickness of the resin layer 3 is preferably 1.0 to 2.0 times the height of the unevenness on the surface of the semiconductor wafer 6 .

(Peeling film 5) In addition, the release film 5 may be provided on the adhesive layer 4 with respect to the adhesive tape 1 for surface protection. The release film 5 is provided for the purpose of protecting the spacer or the release layer, also called a release liner, and the adhesive layer 4, and also for the purpose of smoothing the adhesive. Examples of the constituent material of the release film 5 include synthetic resin films such as polyethylene, polypropylene, and polyethylene terephthalate, paper, and the like. The surface of the release film 5 may be subjected to release treatment such as polysiloxane treatment, long-chain alkyl treatment, and fluorine treatment as necessary in order to improve the releasability of the self-adhesive layer 4 . In addition, if necessary, the adhesive layer 4 is not reacted by exposure to unintended ultraviolet rays such as ambient ultraviolet rays, and it is also desirable to apply ultraviolet rays protection treatment. The thickness of the release film 5 is usually about 10 to 100 μm, and ideally about 25 to 50 μm.

The total thickness of the adhesive tape 1 for electronic components of the present invention is 450 μm or less. In the present invention, the total thickness refers to the thickness in the state of being used as the tape for electronic components, and when the release film 5 is provided, the thickness of the tape 1 for electronic components after the release film 5 is peeled off. When the total thickness of the adhesive tape 1 for electronic components exceeds 450 μm, when the adhesive tape 1 for electronic components is thermally bonded to the surface of the semiconductor wafer 6, thermal conductivity deteriorates and it takes time to soften the resin layer 3. It takes time for the tape 1 for electronic parts to be sufficiently conformed to the unevenness 61 on the surface of the semiconductor wafer 6 .

＜How to use＞ Next, a method of using the tape 1 for electronic components of the present invention, that is, a method of processing the semiconductor wafer 6 will be described.

Specifically, first, as shown in FIG. 2(A), the release film 5 of the tape 1 for electronic components is peeled off from the adhesive layer 4, and as shown in FIG. 2(B), on the circuit pattern surface of the semiconductor wafer 6 (surface), the adhesive layer 4 is a bonding process in which the adhesive tape 1 for electronic components is bonded as a bonding surface. In this case, it is preferable to heat and bond at a temperature of 50 to 100°C, and it is more preferable to heat and bond at a temperature of 60 to 80°C. At this time, since the nano-indenter of the resin layer 3 is used, the depth of the indenter of the nano-indenter at any temperature of 60°C to 80°C measured in accordance with ISO14577 is 10,000 nm or more. The tape 1 is fully conformable to the unevenness 61 on the surface of the semiconductor wafer 6 in a short time. The bonding speed should be above 3mm/S. The heating during bonding is performed through the heating of the chuck holding the semiconductor wafer 6 or the bonding roller.

After the bonding process, the cutting process for cutting the tape 1 for electronic components is carried out along the side surface of the semiconductor wafer 6 through a dicing blade attached to the bonding machine while being held in the chuck. In order to improve the cutting property, the cutting blade may be heated to about 70 to 150°C.

The semiconductor wafer surface protection tape 1 is suitable for use in the configuration where the level difference of the unevenness 61 surface such as bumps formed on the circuit formation surface, that is, the level difference of the circuit formation surface is 10 μm or more, and it is more suitable for the level difference of 100 μm or more. The structure is particularly suitable for a structure with a level difference of 180 μm or more.

After that, as shown in FIG. 2(C) , the back surface of the semiconductor wafer 6, that is, the surface side without the circuit pattern, the thickness of the semiconductor wafer 6 is adjusted to a specific thickness, for example, 10 to 200 μm, and the grinding machine 7 is carried out. And the grinding process of grinding. After that, a polishing process such as dry polishing may be performed for the final processing. At this time, since the tape 1 for electronic components is sufficiently conformable to the unevenness 61 on the surface of the semiconductor wafer 6, it can be used as a leakage suppressor. In addition, since the unevenness of the surface of the tape 1 for electronic components is suppressed, the force from the grinder 7 is applied uniformly to the back surface of the semiconductor wafer 6, and the thickness accuracy is good, and the semiconductor wafer 6 is ground and polished, and the semiconductor wafer 6 is ground and polished. Indentation.

After that, when the tape 1 for electronic components is photopolymerizable, the adhesive force of the adhesive layer 4 is lowered by irradiating energy rays, and the tape 1 for electronic components is peeled off from the semiconductor wafer 6 . However, a wafer dicing/die bonding film (not shown) may be attached to the grinding/polishing surface side of the semiconductor wafer 6 without the circuit pattern before the tape 1 for electronic components is peeled off after the energy ray irradiation.

However, in the present embodiment, the adhesive layer 4 is provided on the upper surface of the resin layer, but the adhesive layer 4 may not be provided if it is not necessary. In this case, the back surface of the semiconductor wafer 6 is ground and polished by directly bonding the semiconductor wafer 6 to the resin layer, and after the grinding and polishing are completed, the tape 1 for electronic components is peeled off from the semiconductor wafer 6 .

However, in the present embodiment, the example in which the tape 1 for electronic components is used for grinding and polishing of the semiconductor wafer 6 has been described, but it is not limited to this, and it can be used for electronic components having irregularities on the surface. It is used for surface protection of parts such as cutting and transportation. Examples of electronic components other than the semiconductor wafer 6 include glass having a level difference of about 200 μm on the surface, or a package having bumps with a height of about 200 μm.

<Example> Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited to these examples.

[Preparation of adhesive layer composition] [Adhesive Layer Composition A] To 100 parts by mass of the copolymer composed of 80 parts by mass of isooctyl 2-acrylate, 15 parts by mass of 2-hydroxyethyl acrylate, and 5 parts by mass of methacrylic acid, add coronate-L (trade name, Nippon Polyurethane Industry Co., Ltd. product) 1.0 mass parts was mixed, and the adhesive composition A was obtained.

[Preparation of Resin Comprising Resin Layer] [Resin B1] As resin B1, an ethylene-butyl acrylate copolymer (EBA) having a butyl acrylate content of 30% and a weight average molecular weight of 100,000 was prepared. The storage modulus coefficient at 70°C of the resin B1 is 9.0×10 ⁴ Pa, the MFR is 30 g/10min, and the molecular weight distribution is 5.8.

[Resin B2] As resin B2, an α-olefin resin having a density of 0.88 and a weight average molecular weight of 40,000 was prepared. The storage modulus of resin B2 at 70°C is 1.4×10 ⁵ Pa, the MFR is 40 g/10min, and the molecular weight distribution is 2.4. [Resin B3] As resin B3, an ethylene-vinyl acetate copolymer (EVA) having a vinyl acetate content of 30% and a weight average molecular weight of 50,000 was prepared. The storage modulus of resin B3 at 70° C. is 6.8×10 ⁴ Pa, the MFR is 60 g/10min, and the molecular weight distribution is 6.3. [Resin B4] As resin B4, an α-olefin resin having a density of 0.90 and a weight average molecular weight of 50,000 was prepared. The storage modulus at 70°C of resin B4 is 2.5×10 ⁵ Pa, the MFR is 20 g/10min, and the molecular weight distribution is 2.4. [Resin B5] As resin B5, an ethylene-vinyl acetate copolymer (EVA) having a vinyl acetate content of 40% and a weight average molecular weight of 40,000 was prepared. The storage modulus of resin B5 at 70°C is 3.6×10 ⁴ Pa, the MFR is 70 g/10min, and the molecular weight distribution is 6.3.

[Production of Tape for Electronic Parts] [Example 1] Resin B1 was extruded to a thickness of 300 μm on a polyethylene terephthalate (PET) film having a thickness of 50 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive layer and the above-mentioned resin layer were bonded and transferred to obtain the tape for electronic components of Example 1 with a thickness of 360 μm.

[Example 2] Resin B1 was extruded to a thickness of 300 μm on a high-density polyethylene (HD) film having a thickness of 130 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive layer and the above-mentioned resin layer were bonded and transferred to obtain the tape for electronic components of Example 2 with a thickness of 440 μm.

[Example 3] Resin B1 was mixed with 20 parts by mass of an alumina filler to 100 parts by mass to obtain a resin composition. On a high density polyethylene (HD) film having a thickness of 130 μm as a base film, the resin layer organism was extruded to a thickness of 300 μm to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive layer and the above-mentioned resin layer were bonded and transferred to obtain the tape for electronic components of Example 3 with a thickness of 440 μm.

[Example 4] Resin B1 was extruded to a thickness of 300 μm on a high-density polyethylene (HD) film having a thickness of 60 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive layer and the above-mentioned resin layer were bonded and transferred to obtain the tape for electronic components of Example 4 with a thickness of 310 μm.

[Example 5] Resin B2 was extruded to a thickness of 300 μm on a high-density polyethylene (HD) film having a thickness of 60 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive layer and the above-mentioned resin layer were bonded and transferred to obtain the tape for electronic components of Example 5 with a thickness of 310 μm. [Example 6] Resin B3 was extruded to a thickness of 300 μm on a polyethylene terephthalate (PET) film having a thickness of 50 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive layer and the above-mentioned resin layer were bonded and transferred to obtain the tape for electronic components of Example 6 with a thickness of 360 μm.

[Comparative Example 1] Resin B1 was extruded to a thickness of 390 μm on a polyethylene terephthalate (PET) film having a thickness of 50 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive bond layer and the said resin surface layer were bonded together, and it transcribe|transferred, and the adhesive tape for electronic components of the comparative example 1 concerning thickness 450 micrometers was obtained.

[Comparative Example 2] Resin B1 was extruded to a thickness of 300 μm on a high-density polyethylene (HD) film having a thickness of 190 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive bond layer and the said resin surface layer were bonded together, and it transcribe|transferred, and the adhesive tape for electronic components of the comparative example 2 concerning a thickness of 500 micrometers was obtained.

[Comparative Example 3] Resin B4 was extruded to a thickness of 300 μm on a polyethylene terephthalate (PET) film having a thickness of 50 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive bond layer and the said resin surface layer were bonded together and transcribe|transferred, and the adhesive tape for electronic components of the comparative example 3 concerning thickness 360 micrometers was obtained.

[Comparative Example 4] Resin B5 was extruded to a thickness of 300 μm on a polyethylene terephthalate (PET) film having a thickness of 50 μm as a base film to form a resin layer, and the resin layer side was subjected to corona treatment. Next, on the spacer of polyethylene terephthalate (PET) with a thickness of 40 μm, the film thickness after drying was 10 μm, and the adhesive composition A was applied and dried to obtain an adhesive layer. Then, the adhesive bond layer and the said resin layer surface were bonded together, and it transcribe|transferred, and the adhesive tape for electronic components of the comparative example 4 concerning thickness 360 micrometers was obtained.

[Characteristic measurement and evaluation test] About the adhesive tapes for electronic components of the said Example and a comparative example, the characteristic measurement and evaluation test were performed as follows. The results are shown in Table 1.

(1) Determination of the pushing depth of the indenter of the nano-indenter About the resin layer concerning an Example and a comparative example, the test piece was produced according to ISO14577-1:2002. The Pu-Song ratio of the test piece was 0.25. Using Nano Indenter G200 (trade name) manufactured by KLA CORPORATION, the penetration depth of the indenter of the nano-indenter at 70° C. of each test piece was measured. For the indenter, a flat cylindrical indenter having a diameter of 1 mm was used, the maximum load was 50 mN, the time until the application of the maximum load was 1 second, and the maximum load holding time was 0.5 seconds. The results are shown in Tables 1 and 2.

(2) Measurement of thermal conductivity of base film For the base films of the examples and comparative examples, XFA500 (trade name) manufactured by LINSESIS was used in accordance with JIS-R1611, and the thermal conductivity at 70° C. was measured under the conditions of a charging voltage of 350 V and a pulse length of 5 mS. The results are shown in Tables 1 and 2.

(3) Measurement of thermal conductivity of resin layer For the resin layers of the examples and comparative examples, XFA500 (trade name) manufactured by LINSESIS was used in accordance with JIS-R1611, and the thermal conductivity at 70°C was obtained. The results are shown in Tables 1 and 2.

(4) Evaluation of fitting speed RAD3510F/8 (trade name) manufactured by LINTEC Co., Ltd. was used as a sticker, and the tapes for electronic parts of the examples and comparative examples were stuck to the semiconductor wafer at a sticking temperature of 70°C. It is used as a semiconductor wafer: a semiconductor wafer with a height of 200 μm and a pitch of 400 μm on the surface, a scribe line with a width of 100 μm, and a chip size of 8 inches with an angle of 5 mm. Lamination was performed at a line speed of 2m/min, 3m/min, and 5m/min, and the following method was used to confirm whether the compliance was good or not. The thickness was measured from the side of the tape for electronic components using a micrometer in the state after the tape for electronic components was attached. When the thickness of the center portion of the semiconductor wafer is taken as α μm and the thickness of the end portion of the semiconductor wafer without bumps is taken as β μm, α-β≦60 μm is judged to be good in compliance. All the configurations with good compliance at all line speeds were evaluated as good products, while at line speeds of 5 m/min, the compliance was not good, but the compliance was good at line speeds of 3 m/min and 2 m/min. The structure was evaluated as △ as an acceptable product, and the conformation was good only when the line speed was 2 m/min, and it was evaluated as × as a defective product, and the conformity was not good when the line speed was 2 m/min. And the evaluation is XX.

(5) Evaluation of environmental stability The tapes for electronic parts of the examples and comparative examples rolled into a roller shape were left to stand at 60° C. or 70° C. for 24 hours, and then it was visually confirmed whether or not resin was exposed to the roller end surfaces. The composition in which exposed resin was not confirmed at 70°C was evaluated as ◎, the composition in which exposed resin was not confirmed at 60°C was evaluated as good product, and the composition in which exposed resin was confirmed was evaluated as defective product. Evaluated as ×. The results are shown in Tables 1 and 2.

As shown in Table 1, in Examples 1 to 6, a nano-indenter was used, and the depth of the indenter at 70°C measured according to ISO14577 was 15,000 nm to 50,000 nm, and the thickness of the resin layer was 240 μm to 300 μm, with a total thickness of 440 μm. For the following reasons, good results were obtained in the evaluation of the bonding speed and environmental stability. In particular, the thermal conductivity of Example 3 at 70°C of the resin layer was 0.7 W/m·K, which was higher than that of the other Examples, and was an excellent result in the evaluation of the bonding speed. Moreover, since the total thickness of the adhesive tapes for electronic parts of Examples 4 and 5 is 310 μm, which is thinner than the other Examples, it was an excellent result in the evaluation of the bonding speed. Although the environmental stability of Example 6 is inferior to that of Examples 1 to 5, the penetration depth at 70° C. measured by the nanoindenter is 50,000 nm, which is large, and the bonding speed is higher. Excellent results in the evaluation.

On the other hand, as shown in Table 2, since the thickness of the resin layer in Comparative Example 1 exceeds 300 μm, and the total thickness in Comparative Example 2 exceeds 450 μm, it is an unfavorable result in the evaluation of the bonding speed. In Comparative Example 3, a nano-indenter was used, and since the depth of indentation of the indenter at 70° C. measured in accordance with ISO14577 was less than 10,000 nm, it was an unfavorable result in the evaluation of the bonding speed. In Comparative Example 4, a nano-indenter was used, and since the indentation depth of the indenter at 70° C. measured in accordance with ISO14577 exceeded 50,000 nm, it was an unsatisfactory result in the evaluation of environmental stability.

1: Tape for electronic parts 2: substrate film 3: resin layer 4: Adhesive layer 5: Peel off the film 6: Semiconductor wafer 61: bump 7: Grinder

1 is a cross-sectional view schematically showing the structure of the tape for electronic components according to the embodiment of the present invention. [ Fig. 2] Fig. 2 is an explanatory diagram for explaining a usage example of the tape for electronic components according to the embodiment of the present invention.

1: Tape for electronic parts

2: substrate film

3: resin layer

4: Adhesive layer

5: Peel off the film

Claims (6)

An adhesive tape for electronic parts is characterized by having a base film, at least one side of the base film has at least one resin layer, an adhesive layer is provided on the surface of the resin layer, and the resin layer is made of The indentation machine, according to ISO14577, has a depth of 10000nm to 50000nm, the thickness of the resin layer is 50μm to 300μm, and the total thickness is 450 μm or less, the weight-average molecular weight of the resin constituting the resin layer is 10,000 to 200,000, and the thickness of the adhesive layer is 1 μm or more and less than 20 μm . The adhesive tape for electronic parts according to claim 1, wherein the thermal conductivity of the aforementioned resin layer at 60~80°C is at least 0.30W/m. above K. The adhesive tape for electronic components according to claim 1 or claim 2, which is attached to the circuit formation surface of a semiconductor wafer provided with a step difference of 10 μm or more. The adhesive tape for electronic parts according to claim 3, wherein the thickness of the resin layer is 1 to 2 times the level difference. A method of processing an electronic component, comprising: bonding the electronic component according to any one of claim 1 to claim 3 on a circuit formation surface of a semiconductor wafer provided with a step difference of 10 μm or more at a temperature of 50 to 100° C. The bonding process of the tape, and the bonding process of grinding the aforementioned semiconductor wafer after the aforementioned bonding process A grinder of the surface on the opposite side of the road forming surface. The processing method of electronic parts according to claim 5, wherein the lamination speed in the lamination process is 3 mm/S or more.

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