KR20170029416A - Protective membrane forming film - Google Patents

Abstract

Provided is a film for forming a protective film which has high strength of a protective film, contributes to improvement of productivity of a chip with a protective film, and which can obtain a chip with a protective film with high reliability. The film for forming a protective film according to the present invention is a film for forming a protective film for forming a protective film for protecting a semiconductor chip and contains an epoxy thermosetting component including an epoxy compound having a glass transition temperature of 220 캜 or higher.

Description

[PROTECTIVE MEMBRANE FORMING FILM]

 The present invention relates to a protective film-forming sheet capable of efficiently forming a protective film having a high adhesive strength on a chip and capable of manufacturing a chip with a protective film having high reliability. To a film for forming a protective film used for manufacturing a semiconductor chip mounted in a so-called face-down manner.

Recently, a semiconductor device using a mounting method called a face down method has been manufactured. In the face-down method, a semiconductor chip (hereinafter simply referred to as a " chip ") having electrodes such as bumps is used on a circuit surface, and the electrode is bonded to the substrate. For this reason, there is a case where the surface (the back surface of the chip) opposite to the circuit surface of the chip is exposed.

The back surface of the exposed chip may be protected by the organic film. Conventionally, a chip having a protective film made of this organic film is obtained by applying a liquid resin on the back surface of a wafer by a spin coat method, drying, and curing the resin to cut the protective film together with the wafer. However, since the thickness precision of the protective film thus formed is not sufficient, the yield of the product may be lowered.

In order to solve the above problem, Patent Document 1 discloses a colored wafer backing film containing a thermosetting resin such as an epoxy resin.

Patent Document 1: JP-A-2010-199541

The present inventors have found that by using an epoxy thermosetting component containing an epoxy compound having specific physical properties, it becomes possible to increase the strength of the protective film obtained by curing the protective film-forming film and to improve the productivity of the chip with a protective film, And thus the present invention has been accomplished. That is, an object of the present invention is to provide a film for forming a protective film, which has high strength of a protective film, contributes to improvement of productivity of a chip with a protective film, and which can obtain a chip with a protective film with high reliability.

The present invention includes the following points.

[1] A film for forming a protective film for forming a protective film for protecting a semiconductor chip,

A film for forming a protective film containing an epoxy thermosetting component comprising an epoxy compound having a glass transition temperature of 220 ° C or higher.

[2] The protective film forming film according to [1], wherein the epoxy compound has a softening point of 60 to 110 ° C.

[3] A film for forming a protective film according to [1] or [2], which contains an acrylic polymer.

[4] The protective film forming film according to any one of [1] to [3], wherein the protective film has a thickness of 1 to 100 μm.

[5] A protective film forming sheet comprising the protective film-forming film according to any one of [1] to [4] laminated on a support sheet.

[6] A method of manufacturing a semiconductor device including the following steps (1) to (4);

Step (1): a step of attaching a film for forming a protective film of the protective film-forming sheet described in [5]

Step (2): a step of heating and curing the protective film forming film to obtain a protective film,

Step (3): a step of separating the protective film-forming film or protective film from the supporting sheet,

Step (4): Step of dicing the adherend and the protective film-forming film or protective film.

According to the protective film forming film of the present invention, a chip with a protective film with high reliability can be produced. Further, since the protective film has high strength and hardens in a short time, the productivity of a chip with a protective film can be improved.

Fig. 1 shows a sheet for forming a protective film of the first embodiment. Fig.
Fig. 2 shows a sheet for forming a protective film of the second embodiment. Fig.
Fig. 3 shows a sheet for forming a protective film of the third embodiment. Fig.
Fig. 4 shows a sheet for forming a protective film of the fourth embodiment. Fig.

Hereinafter, the protective film forming film of the present invention will be described in detail.

[Film for forming a protective film]

The film for forming a protective film according to the present invention is a film for forming a protective film for protecting a semiconductor chip and contains an epoxy thermosetting component including an epoxy compound having a glass transition temperature of at least 200 캜.

Epoxy-based thermosetting component

The epoxy-based thermosetting component preferably includes an epoxy compound having at least specific physical properties, and a combination of the epoxy compound and the thermosetting agent is preferably used. Further, a compound having an epoxy group other than the epoxy compound (hereinafter sometimes simply referred to as " another epoxy compound ") may be used as the epoxy-based thermosetting component.

In the present invention, the epoxy compound having specific physical properties means that the glass transition temperature of the cured product is 220 占 폚 or higher, preferably 220 to 350 占 폚, more preferably 240 to 345 占 폚, particularly preferably 300 to 330 占 폚 Refers to an epoxy compound. By setting the glass transition temperature of the cured product of the epoxy compound within the above range, the film for forming a protective film can be cured in a short time, and the strength of the protective film obtained by curing the protective film forming film can be increased. In short, by using an epoxy compound having the above physical properties, the film for forming a protective film has excellent curability. As a result, the reliability and productivity of the chip with a protective film produced using the protective film forming film according to the present invention are improved. The glass transition temperature of the cured product of the epoxy compound can be measured by the method described in the following Examples.

The softening point of the epoxy compound having specific physical properties in the present invention is preferably 60 to 110 占 폚, more preferably 70 to 100 占 폚, still more preferably 80 to 97 占 폚, particularly preferably 90 to 95 占 폚. By setting the softening point of the epoxy compound within the above range, the curing property of the protective film forming film can be improved. The softening point of the epoxy compound can be measured by the method described in the following examples.

The epoxy compound having specific physical properties in the present invention preferably has a melt viscosity of 1.0 to 25.0 dPa · s, more preferably 2.0 dPa · s to 15.0 dPa · s or less, still more preferably 2.5 to 7.0 dPa · s to be. By setting the melt viscosity of the epoxy compound within the above range, the curing property of the protective film forming film can be improved. The melt viscosity of the epoxy compound is measured by a capillary rheometer (for example, CFT-100D manufactured by Shimadzu Corporation) at a measurement temperature of 150 ° C and a measurement frequency of 1 Hz.

The number average molecular weight (Mn) of the epoxy compound having specific physical properties in the present invention is preferably 200 to 1000, more preferably 300 to 900, still more preferably 400 to 800, 750. By setting the number average molecular weight (Mn) of the epoxy compound within the above range, the curing property of the protective film forming film can be improved. The number average molecular weight of the epoxy compound is a value in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

Specific examples of the epoxy compound having specific physical properties in the present invention are not particularly limited as long as it is an epoxy compound satisfying the above physical properties, and for example, a condensed ring aromatic compound having an epoxy group can be mentioned.

Having an epoxy group Condensation  Cyclic aromatic compound

In the present invention, the condensed cyclic aromatic compound having an epoxy group means a compound in which an epoxy group is bonded directly or via an alkoxy group to a condensed cyclic aromatic hydrocarbon having a condensed ring also composed of aromatic rings. The number of carbon atoms of the condensed ring aromatic hydrocarbon is not particularly limited, but is preferably 8 to 55, more preferably 12 to 45, and still more preferably 16 to 35.

The curing property of the film for forming a protective film is excellent by including the condensed cyclic aromatic compound having an epoxy group and the reliability and productivity of a chip with a protective film produced using the protective film forming film according to the present invention can be improved.

Examples of the condensed cyclic aromatic compound having an epoxy group include a condensed ring in which a glycidyl ether group is bonded (an epoxy group is bonded via a methoxy group) and is represented by, for example, the following general formula (I) or Compounds.

[Chemical Formula 1]

Formula 1

(Wherein R ¹ represents a hydrogen atom or an alkyl group having 1 to 10 carbon atoms and m represents an integer of 2 to 6. When R ¹ represents an alkyl group , The number of carbon atoms thereof is preferably from 1 to 6. m is preferably from 2 to 4.)

(2)

(2)

(Wherein, in the general formula (II), CR ¹ and CR ² represent condensed-ring-type aromatic hydrocarbons, these condensed-ring-type aromatic hydrocarbons may be the same or different, R ² is a divalent hydrocarbon group, R ³ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or a glycidyl ether group, n is an integer of 1 to 3, p is an integer of 0 to 10, and p Is 0, R ² represents a single bond and q represents an integer of 1 to 3. The carbon number of R ² is preferably 1 to 6. When R ³ is an alkyl group, the carbon number thereof is 1 to 6 N is preferably from 1 to 2, p is preferably from 0 to 4, and q is preferably from 1 to 2. [

The substituent a of R ^{2 in} the general formula (II) includes a phenyl group or a phenyl group having a substituent b. The substituent b may be an alkyl group having 1 to 6 carbon atoms or a glycidyl ether group, and is preferably an alkyl group having 1 to 4 carbon atoms.

Examples of the condensed ring of the condensed cyclic aromatic compound include a naphthalene ring, an anthracene ring, a phenanthrene ring and a 3,4-benzopyrylene ring. Among them, a naphthalene ring is preferable from the viewpoint of the curability of the film for forming a protective film.

Specific examples of the compound represented by the general formula (I) or (II) and having a naphthalene ring as the condensed ring include 1,1-bis (2,7-diglycidyloxy-1-naphthyl) (2-glycidyloxy-1-naphthyl) -1- (2-glycidyloxy-1-naphthyl) alkane represented by the following general formula (IV) 1,1-bis (2-glycidyloxy-1-naphthyl) alkane represented by the general formula (V).

(3)

(3)

[Chemical Formula 4]

Formula 4

[Chemical Formula 5]

Formula 5

(Wherein R ⁴ represents a monovalent or divalent hydrocarbon group, and the hydrocarbon group may have a substituent. When the compounds represented by the above general formulas (III) to (V) are used in combination, R ⁴ may be the same or different Maybe.)

R ⁴ in formulas (III) to (V) is more preferably a divalent hydrocarbon group which may have a substituent represented by the following formula.

[Chemical Formula 6]

6

Each of R ⁵ and R ⁶ independently represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a phenyl group or a phenyl group having a substituent c When R ⁵ and R ⁶ are phenyl groups having a substituent c, examples of the substituent c include an alkyl group having 1 to 10 carbon atoms or a glycidyl ether group, preferably a hydrogen atom or an alkyl group having 1 to 6 carbon atoms a. R ⁵ and R ⁶ as is particularly preferably a hydrogen atom in the curing point of view of the film for forming a protective film. in the formula, n is an integer from 0-4, preferably 0-3, more preferably 1. When n is 0, the structure of the above formula represents a single bond.)

The general formula (III) ~ R ⁴ in the curing of the point of view of the film formation, the protective film among the compounds represented by (V), formula (III) represents a compound preferable, and in particular the general formula (III) a methylene (-CH ₂ -).

The epoxy equivalent of the condensed cyclic aromatic compound having an epoxy group is preferably 150 to 180 g / eq, more preferably 160 to 170 g / eq. By setting the epoxy equivalent in the above range, the film for forming a protective film is excellent in curability.

The content of the condensed cyclic aromatic compound having an epoxy group is preferably from 1 to 20 parts by mass, more preferably from 2 to 18 parts by mass, further preferably from 2.5 to 20 parts by mass based on 100 parts by mass of the total solid content constituting the protective film- To 15 parts by mass. By setting the content of the condensed cyclic aromatic compound having an epoxy group within the above range, the curing property of the protective film forming film can be improved.

In the protective film-forming film of the present invention, other epoxy compounds may be used together with an epoxy compound having specific physical properties.

Other epoxy compounds

As the other epoxy compounds, conventionally known various epoxy compounds which do not have the above-mentioned specific properties can be used. Specific examples thereof include bisphenol A diglycidyl ether or hydrogenated product thereof, o-cresol novolak type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, And epoxy compounds having two or more functional groups in the molecule, such as phenylene skeleton-type epoxy resins. These may be used alone or in combination of two or more.

When other epoxy compounds are used, the content thereof is preferably 5 to 40 parts by mass, more preferably 10 to 35 parts by mass, further preferably 15 to 40 parts by mass with respect to 100 parts by mass of the total solid content constituting the protective film- To 30 parts by mass. When the content of the other epoxy compound is within the above range, adhesion of the protective film obtained by curing the protective film forming film to the semiconductor chip is improved. When the protective film forming film is laminated on the supporting sheet, the peeling force between the protective film forming film and the supporting sheet can be controlled, and as a result, defective transfer of the protective film forming film can be prevented.

Heat curing agent

The thermosetting agent functions as a curing agent for epoxy compounds or other epoxy compounds having specific physical properties. Preferable examples of the heat curing agent include compounds having two or more functional groups capable of reacting with an epoxy group in one molecule. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group or an acid anhydride. Among these, a phenolic hydroxyl group, an amino group or an acid anhydride is preferable, and phenolic hydroxyl group or amino group is more preferable.

Specific examples of the phenol-based curing agent include polyfunctional phenol resin, biphenol, novolac phenol resin, dicyclopentadiene phenol resin, zeolite-type phenol resin, and aralkyl phenol resin.

A specific example of the amine-based curing agent includes DICY (dicyandiamide).

These may be used singly or in combination of two or more.

The content of the thermosetting agent is preferably 0.1 to 500 parts by mass, more preferably 1 to 200 parts by mass, still more preferably 2 to 10 parts by mass, relative to 100 parts by mass of the total amount of the epoxy compound and the other epoxy compound having specific physical properties Wealth. By setting the content of the thermosetting agent within the above range, the protective film obtained by curing the protective film-forming film is excellent in adhesion to a semiconductor chip and the protective film-forming film in a semiconductor wafer.

Hardening accelerator

In order to adjust the rate of thermal curing of the protective film forming film, a curing accelerator may be used. Preferred curing accelerators include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol and tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole, 2- Imidazoles such as 4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-hydroxymethylimidazole; Organic phosphines such as diphenylphosphine and triphenylphosphine; tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphine tetraphenylborate; and the like. These may be used singly or in combination of two or more.

The curing accelerator is contained in an amount of preferably 0.01 to 10 parts by mass, more preferably 0.1 to 3 parts by mass based on 100 parts by mass of the total amount of the epoxy compound, the other epoxy compound and the thermosetting agent having specific physical properties. When the content of the curing accelerator is within the above range, the protective film obtained by curing the protective film-forming film even when exposed to high temperature and high humidity is excellent in adhesion to a semiconductor chip and high reliability even when exposed to strict reflow conditions Can be achieved.

Energy line  Curable component

The protective film forming film of the present invention may contain an energy ray curable component in addition to the above-described epoxy thermosetting component. In the case where the film for forming a protective film contains an energy ray-curable component, since the protective film forming film can be preliminarily cured by energy ray irradiation, the cohesive force of the protective film forming film So that the adhesion between the protective film-forming film and the support sheet can be lowered. As a result, the chip with a film for forming a protective film can be easily separated from the supporting sheet, and the chip with a film for forming a protective film can be easily picked up. As the energy ray curable component, a compound having a reactive double bond group may be used alone or in combination of an energy ray reactive compound and a photopolymerization initiator.

Energy line  Reactive compound

Specific examples of the energy ray-reactive compound include trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, and dicyclopentadiene skeleton-containing polyfunctional acrylate. In addition, oligomer esters such as oligoester acrylate, urethane acrylate Acrylate compounds such as acrylic oligomers, epoxy oligomers, epoxy acrylates, polyether acrylates and itaconic acid oligomers, and the like can be given as the acrylate compounds having a relatively low molecular weight. Such compounds have at least one polymerizable carbon-carbon double bond in the molecule.

The content of the energy ray reactive compound is preferably 1 to 5 parts by mass, and more preferably 2 to 4 parts by mass, based on 100 parts by mass of the total solid content constituting the protective film forming film.

Light curing Initiator

By combining a photopolymerization initiator with an energy ray-reactive compound, the polymerization curing time can be shortened and the amount of light irradiation can be reduced.

Specific examples of such photopolymerization initiators include benzophenone, acetophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoic acid, methyl benzoin benzoate, benzoin 1-hydroxycyclohexyl phenyl ketone, benzyl diphenyl sulfide, tetramethyl thiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, 1 2-methyl-1- [4- (1-methylvinyl) phenyl] propanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and? -Chloranthene Quinone, and the like. The photopolymerization initiator may be used singly or in combination of two or more.

The content of the photopolymerization initiator is preferably 0.1 to 10 parts by mass, more preferably 1 to 7 parts by mass, based on 100 parts by mass of the energy ray-reactive compound.

When the content of the photopolymerization initiator is less than 0.1 part by mass, unsatisfactory curability may not be obtained due to insufficient photopolymerization, while when it exceeds 10 parts by mass, residues which do not contribute to photopolymerization are produced, which may cause a problem.

The polymer component

The protective film forming film may contain a polymer component. The polymer component is added to the film for forming a protective film, with the main purpose of imparting sheet-like retention to the film for forming the protective film.

In order to achieve the above object, the weight average molecular weight (Mw) of the polymer component is usually 20,000 or more, preferably 20,000 to 3,000,000. The value of the weight average molecular weight (Mw) is a value measured by gel permeation chromatography (GPC) (polystyrene standard). For example, the high-speed GPC apparatus "HLC-8120 GPC" manufactured by Tosoh Corporation, the high-speed columns "TSK gurd column H _XL -H", "TSK Gel GMH _XL ", "TSK Gel G2000 H _Quot ; _XL " (all above, all of which are manufactured by Sokosan Co., Ltd.) are used in this order, and the detector is set to a differential refractometer at a column temperature of 40 캜 and a feed rate of 1.0 mL / min.

For the sake of distinguishing the curable polymer from the later-described curable polymer, the polymer component does not have the curable functional group described later.

As the polymer component, an acrylic polymer, a polyester, a phenoxy resin (limited to those having no epoxy group for the sake of distinguishing from a curable polymer to be described later), polycarbonate, polyether, polyurethane, polysiloxane and rubber polymer can be used . In addition, an acrylic urethane resin obtained by reacting two or more kinds of these, for example, an urethane prepolymer having an isocyanate group at the molecular end with an acrylic polyol which is an acrylic polymer having a hydroxyl group may be used. Further, two or more kinds of polymers combined with each other may be used, or a combination of two or more of them may be used.

The content of the polymer component is preferably 10 to 60 parts by mass, more preferably 15 to 40 parts by mass, and still more preferably 15 to 30 parts by mass, based on 100 parts by mass of the total solid content of the protective film forming film. When the content of the polymer component in the film for forming a protective film is within the above-mentioned range, when the polymer components are variously combined, the adhesive property of the protective film forming film to the adherend can be stably obtained stably.

Acrylic polymer

As the polymer component, an acrylic polymer is preferably used. The glass transition temperature (Tg) of the acrylic polymer is preferably in the range of -60 to 50 占 폚, more preferably -50 to 40 占 폚, and still more preferably -40 to 30 占 폚. When the glass transition temperature of the acrylic polymer is high, the adhesion to the adherend (semiconductor wafer or the like) of the protective film-forming film is lowered and the film can not be transferred to the adherend. The protective film obtained by curing the protective film-forming film may peel off. If the glass transition temperature of the acrylic polymer is too low, the peeling force between the protective film forming film and the supporting sheet becomes large, which may cause transfer failure of the protective film forming film.

The Tg of the acrylic polymer is a value obtained from the formula of FOX.

The weight average molecular weight (Mw) of the acrylic polymer is preferably 100,000 to 1,500,000. When the weight average molecular weight of the acrylic polymer is high, the initial adhesion of the film for forming a protective film is lowered, so that the film can not be transferred to the adherend. If the weight average molecular weight of the acrylic polymer is too low, the adhesion between the protective film-forming film and the supporting sheet becomes high, and the transfer film of the protective film may be defective.

The acrylic polymer includes (meth) acrylic acid ester monomer or a derivative thereof at least in the constituent monomers. Further, in the present specification, (meth) acrylic is sometimes used to mean both acrylic and methacrylic.

(Meth) acrylic acid ester monomers or derivatives thereof include (meth) acrylic acid alkyl esters having 1 to 18 carbon atoms in the alkyl group, (meth) acrylic esters having a cyclic skeleton, (meth) acrylic acid esters having a hydroxyl group (Meth) acrylate, and (meth) acrylic acid esters having a carboxyl group.

Examples of the (meth) acrylic acid alkyl ester having 1 to 18 carbon atoms in the alkyl group include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (Meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl acrylate, decyl Decyl, octadecyl (meth) acrylate, and the like.

Examples of the (meth) acrylic acid ester having a cyclic skeleton include (meth) acrylic acid cycloalkyl ester, (meth) acrylic acid benzyl ester, isobornyl (meth) acrylate, dicyclopentanyl (Meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, imide (meth) acrylate, and the like.

Examples of the (meth) acrylic acid ester having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 2-hydroxybutyl (meth) acrylate.

Examples of the (meth) acrylic acid ester having an amino group include monoethylamino (meth) acrylate, diethylamino (meth) acrylate and the like.

Examples of the (meth) acrylic acid ester having a carboxyl group include 2- (meth) acryloyloxyethyl phthalate, 2- (meth) acryloyloxypropyl phthalate and the like.

These may be used alone or in combination of two or more.

It is preferable to use a monomer having a hydroxyl group as a monomer constituting the acrylic polymer. When such a monomer is used, the compatibility of the acrylic polymer with the acrylic polymer is improved when a hydroxyl group is introduced into the acrylic polymer and the film for forming the protective film contains an energy ray curable component. Examples of the monomer having a hydroxyl group include vinyl alcohol, N-methylol (meth) acrylamide, and the like, in addition to the (meth) acrylic acid ester having a hydroxyl group.

As the monomer constituting the acrylic polymer, a monomer having a carboxyl group may be used. When such a monomer is used, the carboxyl group is introduced into the acrylic polymer, and when the protective film forming film contains an energy ray curable component, the compatibility with the acrylic polymer is improved. Examples of the monomer having a carboxyl group include (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid and the like in addition to the (meth) acrylic acid ester having a carboxyl group. However, since the carboxyl group and the epoxy group in the epoxy thermosetting component react with each other, the amount of the carboxyl group-containing monomer is preferably small.

(Meth) acrylonitrile, (meth) acrylamide, vinyl acetate, styrene, ethylene, alpha -olefin, or the like may be used as the monomer constituting the acrylic polymer.

The acrylic polymer may be crosslinked. The crosslinking is carried out by reacting the acrylic polymer before crosslinking with a crosslinkable functional group such as a hydroxyl group and by adding a crosslinking agent to the composition for forming a protective film forming film so that the crosslinkable functional group and the functional group possessed by the crosslinking agent react with each other. By crosslinking the acrylic polymer, it becomes possible to control the cohesive force of the protective film forming film. Further, by adjusting the crosslinking density of the acrylic polymer, it is possible to control the glass transition temperature after thermal curing of the protective film forming film. The crosslinking density can be controlled by the addition amount of the crosslinking agent described later.

Examples of the crosslinking agent include organic polyvalent isocyanate compounds and organic polyvalent organic compounds.

Examples of the organic polyisocyanate compound include an aromatic polyisocyanate compound, an aliphatic polyisocyanate compound, an alicyclic polyisocyanate compound, a trimer of these organic polyisocyanate compounds, and a terminal isocyanate urethane prepolymer obtained by reacting these organic polyisocyanate compounds with a polyol compound. .

Specific examples of the organic polyisocyanate compound include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane- Diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexyl Methane-2,4'-diisocyanate, lysine isocyanate, and polyhydric alcohol adducts thereof.

Specific examples of the organic polyhydric compound include N, N'-diphenylmethane-4,4'-bis (1-aziridinecarboxamide), trimethylolpropane-tri- Methane-tri-? - aziridinyl propionate and N, N'-toluene-2,4-bis (1-aziridine carboxamide) triethylene melamine.

The crosslinking agent is used in a proportion of usually 0.01 to 20 parts by mass, preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass based on 100 parts by mass of the acrylic polymer before crosslinking.

In the present invention, when the content of the component constituting the protective film forming film is determined on the basis of the content of the polymer component, when the polymer component is the crosslinked acrylic polymer, the content of the acrylic polymer before the crosslinking The content of the polymer.

Non-acrylic  Suzy

As the polymer component, it is possible to use a polyester, a phenoxy resin (limited to those having no epoxy group for the sake of distinguishing from a curable polymer to be described later), polycarbonate, polyether, polyurethane, polysiloxane, rubber- Acrylic resin may be used. The non-acrylic resin may be used singly or in combination of two or more. As such a resin, the weight average molecular weight is preferably 20,000 to 100,000, more preferably 20,000 to 80,000.

The glass transition temperature of the non-acrylic resin is preferably in the range of -30 to 150 占 폚, more preferably -20 to 120 占 폚.

When a non-acrylic resin is used in combination with the above-described acrylic polymer, the protective film forming film is transferred to the adherend with a sheet for forming a protective film, so that the separation between the supporting sheet and the protective film forming film is more easily performed And the film for forming a protective film follows the transfer surface, and the occurrence of voids and the like can be suppressed.

When the non-acrylic resin is used in combination with the above-mentioned acrylic polymer, the content of the non-acrylic resin is preferably 1: 99 to 70: 30 in the mass ratio of the non-acrylic resin to the acrylic polymer (non-acrylic resin: acrylic polymer) , More preferably in the range of 1:99 to 60:40. When the content of the non-acrylic resin is within this range, the above effects can be obtained.

The curable polymer component

A curable polymer component may be added to the protective film forming film. The curable polymer component combines the properties of an epoxy-based thermosetting component or an energy ray-curable component and the properties of a polymer component.

The curable polymer component is a polymer having a curing functional group. The curing functional group is a functional group capable of reacting with each other to form a three-dimensional network structure, and includes a functional group reacting by heating or a functional group reacting by an energy line. The curing functional group may be added to the unit of the continuous structure which becomes the skeleton of the curable polymer component or may be added to the terminal. When a curing functional group is added to a unit of a continuous structure which becomes a skeleton of the curable polymer component, the curing functional group may be added to the side chain or directly to the main chain. The weight average molecular weight (Mw) of the curable polymer component is usually 20,000 or more from the viewpoint of achieving the purpose of imparting sheet-like retention to the protective film forming film.

Examples of the functional group which reacts by heating include an epoxy group. Examples of the curable polymer component having an epoxy group include a high molecular weight epoxy group-containing compound and a phenoxy resin having an epoxy group. High molecular weight epoxy group-containing compounds are disclosed, for example, in JP-A-2001-261789.

The same polymer as the above-mentioned acrylic polymer may be a polymer obtained by polymerization using a monomer having an epoxy group as a monomer (an epoxy group-containing acrylic polymer). Examples of the monomer having an epoxy group include (meth) acrylic acid esters having an epoxy group such as glycidyl (meth) acrylate.

When an epoxy group-containing acrylic polymer is used, the preferred embodiment thereof is the same as the acrylic polymer except for the epoxy group.

When the curable polymer component having an epoxy group is used, the above-mentioned heat curing agent or a curing accelerator may be used in combination.

The functional group which reacts with the energy ray is (meth) acryloyl group. As the curable polymer component having a functional group which reacts with an energy ray, an acrylate compound having a polymerization structure such as polyether acrylate and the like can be used.

For example, the functional group Y capable of reacting with the functional group X (for example, an isocyanate group when the functional group X is a hydroxyl group, etc.) and a functional group capable of reacting with the functional group X by energy ray irradiation are added to the starting polymer having the functional group X such as a hydroxyl group in the side chain A polymer prepared by reacting a low-molecular compound having a reactive functional group may be used.

In this case, when the raw polymer corresponds to the above-mentioned acrylic polymer, the preferred embodiment of the raw polymer is the same as the acrylic polymer.

When a curable polymer component having a functional group reactive with an energy ray is used, a photopolymerization initiator may be used in combination as in the case of using an energy ray curable component.

weapon filler

The protective film-forming film preferably contains an inorganic filler. The incorporation of the inorganic filler into the protective film-forming film makes it easy to adjust the thermal expansion coefficient of the protective film after curing and optimizes the thermal expansion coefficient of the protective film after curing to the adherend, thereby improving the reliability of the chip with protective film. In addition, the moisture absorption rate of the protective film after curing can be reduced.

In addition, by performing laser marking on the protective film, the inorganic filler is exposed to the portion removed by the laser beam, and the reflected light is diffused, so that it has a color close to white. Thus, when the protective film-forming film contains a coloring agent to be described later, there is an effect that a contrast difference is obtained at the portion different from the laser marking portion, and the factor becomes clear.

Preferred inorganic fillers include powders such as silica, alumina, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, boron nitride and the like, spherical beads thereof, single crystal fibers and glass fibers. Among these, silica filler and alumina filler are preferable. The inorganic fillers may be used alone or in combination of two or more.

The content of the inorganic filler for obtaining the aforementioned effect more reliably is preferably from 10 to 70 parts by mass, more preferably from 40 to 70 parts by mass, more preferably from 40 to 70 parts by mass based on 100 parts by mass of the total solid content constituting the protective film- And particularly preferably 50 to 65 parts by mass.

The average particle diameter of the inorganic filler is preferably 0.02 to 20 占 퐉, more preferably 0.05 to 10 占 퐉. The average particle diameter of the inorganic filler is determined by measuring the major axis diameter of 20 randomly selected inorganic fillers by an electron microscope and calculating the number average particle diameter calculated as the arithmetic mean value.

coloring agent

The protective film-forming film may contain a coloring agent. By combining the coloring agent, it is possible to block infrared rays and the like, so that it is possible to prevent the malfunction of the semiconductor device caused by the infrared rays or the like generated from the peripheral devices. In addition, when engraving is performed on the protective film by means such as laser marking, there is an effect that marks such as characters and symbols can be easily recognized. That is, in a semiconductor chip having a protective film, the surface of the protective film is printed by a laser marking method (a method of performing printing by removing the protective film surface by laser light) on the surface of the protective film. The difference in contrast between the portion removed by the light and the portion not removed is sufficiently obtained, and the visibility is improved

As the colorant, organic or inorganic pigments and dyes are used. Of these, black pigments are preferable from the viewpoint of electromagnetic wave shielding and infrared rays. Examples of the black pigment include carbon black, iron oxide, manganese dioxide, aniline black, activated carbon, and the like, but are not limited thereto. From the viewpoint of improving the reliability of a semiconductor device equipped with a protective film-attached chip, carbon black is particularly preferable. The colorants may be used singly or in combination of two or more kinds.

The content of the colorant is preferably 0.1 to 35 parts by mass, more preferably 0.5 to 25 parts by mass, and particularly preferably 1 to 15 parts by mass, based on 100 parts by mass of the total solid content of the protective film forming film.

Coupling agent

The coupling agent having a functional group reacting with an inorganic substance and a functional group reacting with an organic functional group may be used for improving the adhesiveness, adhesiveness and / or cohesiveness of a protective film to an adherend of a protective film forming film. By using a coupling agent, the water resistance of the protective film obtained by curing the protective film-forming film can be improved without deteriorating the heat resistance. Examples of such a coupling agent include a titanate-based coupling agent, an aluminate-based coupling agent, and a silane coupling agent. Among them, a silane coupling agent is preferable.

As the silane coupling agent, a silane coupling agent is preferably used in which the functional group reactive with the organic functional group is a group which reacts with a functional group such as an epoxy-based thermosetting component, a polymer component, or a curable polymer component.

Examples of such silane coupling agents include? -Glycidoxypropyltrimethoxysilane,? -Glycidoxypropylmethyldiethoxysilane,? - (3,4-epoxycyclohexyl) ethyltrimethoxysilane,? - Aminopropyltrimethoxysilane, N-6- (aminoethyl) -? - aminopropyltrimethoxysilane, N-6- (aminoethyl) (Meth) acrylate, N-phenyl-gamma -aminopropyltrimethoxysilane,? -Ureidopropyltriethoxysilane,? -Mercaptopropyltrimethoxysilane,? -Mercaptopropylmethyldimethoxysilane, bis Triethoxysilylpropyl) tetrasulfane, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazolylsilane and the like. These may be used singly or in combination of two or more.

The content of the silane coupling agent is usually 0.1 to 20 parts by mass, preferably 0.2 to 10 parts by mass, and more preferably 0.3 to 5 parts by mass, based on 100 parts by mass of the total solid content constituting the protective film forming film. If the content of the silane coupling agent is less than 0.1 part by mass, the above effect may not be obtained. If the content is more than 20 parts by mass, there is a possibility of causing outgas.

General purpose additive

In addition to the above, various additives may be added to the protective film-forming film if necessary. Examples of the various additives include a leveling agent, a plasticizer, an antistatic agent, an antioxidant, a gettering agent, a chain transfer agent, and a releasing agent.

The film for forming a protective film is obtained by using a composition (composition for forming a protective film) obtained by mixing an epoxy-based thermosetting component containing an epoxy compound having a specific physical property with each of the above-mentioned components to be blended as required. The protective film forming composition may be previously diluted with a solvent or may be added to a solvent at the time of mixing. The composition for forming a protective film may be diluted with a solvent at the time of use.

Examples of such solvents include ethyl acetate, methyl acetate, diethyl ether, dimethyl ether, acetone, methyl ethyl ketone, acetonitrile, hexane, cyclohexane, toluene and heptane.

The film for forming a protective film has an initial adhesion and curability, and is easily adhered to the adherend under normal temperature or heating under an uncured state. Further, the protective film forming film may be heated at the time of pressing. And finally cured to provide a protective film having a high impact resistance, excellent adhesive strength, and sufficient reliability even under severe high temperature and high humidity conditions. The protective film forming film may have a single-layer structure or a multi-layer structure.

The thickness of the protective film-forming film is preferably 1 to 100 占 퐉, more preferably 2 to 90 占 퐉, and particularly preferably 3 to 80 占 퐉.

[Sheet for forming a protective film]

The sheet for forming a protective film according to the present invention is formed by laminating the above-mentioned protective film forming film on a supporting sheet. The sheet for forming a protective film is attached to various adherends, and if necessary, the adherend is subjected to necessary processing such as dicing on the sheet for forming a protective film. Thereafter, the film for forming a protective film is fixed and remained on the adherend, and the supporting sheet is peeled off. That is, it is used in a process including a step of transferring a film for forming a protective film from a support sheet to an adherend.

The shape of the protective film-forming sheet is not limited to a sheet-like shape, but may be a strip having a long length, which may be rolled up and stored. The protective film forming film may have the same shape as the supporting sheet. The protective film-forming sheet is prepared in such a way that the protective film-forming film can have the shape substantially identical to that of the wafer or the shape of the wafer, and the protective film- A molding configuration may be adopted.

As the support sheet, a release sheet can be exemplified, and a pressure-sensitive adhesive sheet described later can also be used.

Examples of the peeling sheet include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, a polyethylene naphthalate film, (Meth) acrylate copolymer film, an ethylene / (meth) acrylic acid ester copolymer film, a polystyrene film, a polycarbonate film, a poly (ethylene terephthalate) film, a polyethylene terephthalate film, a polyurethane film, an ethylene vinyl acetate copolymer film, an ionomer resin film, A mid-film, a fluororesin film, or the like is used. These crosslinked films are also used. Or may be laminated films thereof.

The surface tension of the surface of the release sheet in contact with the protective film forming film is preferably 40 mN / m or less, more preferably 37 mN / m or less, particularly preferably 35 mN / m or less. The lower limit is usually about 25 mN / m. Such a release sheet having a relatively low surface tension can be obtained by appropriately selecting a material and can also be obtained by applying a release agent to the surface of the release sheet and carrying out a release treatment.

As the releasing agent used for the peeling treatment, an alkyd type, a silicone type, a fluorine type, an unsaturated polyester type, a polyolefin type, a wax type and the like are used, and in particular, an alkyd type, silicone type or fluorine type releasing agent is preferable because it has heat resistance.

In order to peel off the surface of a film or the like to be the base of the release sheet by using the release agent, the release agent may be directly applied as a solvent or diluted with a solvent or emulsified and applied by a gravure coater, a Meyer bar coater, an air knife coater, And the release sheet coated with the release agent may be provided at room temperature or under heating or may be cured by electron beam to form the release agent layer.

The surface tension of the release sheet may be adjusted by laminating the films by wet lamination, dry lamination, hot melt lamination, melt extrusion lamination, coextrusion processing, or the like. That is, a film whose surface tension on at least one surface is within a preferable range of the surface of the above-mentioned peeling sheet in contact with the protective film-forming film is set so that the surface thereof is in contact with the protective film- A laminate may be prepared and a release sheet may be used.

In the case where the adherend is subjected to necessary processing such as dicing on the protective film-forming sheet, it is preferable to use a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed thereon as a support sheet. In this embodiment, the protective film-forming film is laminated on the pressure-sensitive adhesive layer formed on the support sheet. As the base material of the adhesive sheet, the above-mentioned films exemplified as the release sheet can be mentioned. The pressure-sensitive adhesive layer may be of a weakly sticky one having an adhesive force enough to peel off the protective film forming film, or an energy ray curable one having an adhesive force lowered by energy ray irradiation. The pressure-sensitive adhesive layer is formed by a conventionally known various pressure-sensitive adhesives (for example, general-purpose pressure-sensitive adhesives such as rubber, acrylic, silicone, urethane or vinyl ether, pressure sensitive adhesives with surface irregularities, energy ray curable pressure sensitive adhesives, thermal expansion component- can do.

When the protective film forming sheet has such a constitution, the adhesion between the supporting sheet and the protective film forming film is maintained when the protective film forming sheet functions as a dicing sheet for supporting the adherend in the dicing step, The effect of suppressing peeling of the chip with a film for forming a protective film from the supporting sheet in the dicing step can be obtained. In the case where the protective film-forming sheet functions as a dicing sheet for supporting the adherend in the dicing step, it is not necessary to dice another dicing sheet on the wafer with film for forming a protective film in the dicing step , The manufacturing process of the semiconductor device can be simplified.

In the case where the protective film forming sheet has a preforming configuration, the protective film forming sheet may have the following first, second, or third configuration. Hereinafter, each constitution of the protective film forming sheet 10 will be described with reference to Figs. 1 to 3. Fig. 1 to 3 show a configuration in which a pressure-sensitive adhesive sheet is used as a support sheet.

As shown in Fig. 1, the first configuration is a configuration in which an adhesive sheet 3 on which a pressure-sensitive adhesive layer 2 is formed on a substrate 1 is detachably formed on one side of a protective film forming film 4. In the case of employing the first configuration, the protective film forming sheet 10 is affixed to the jig 7 by the pressure-sensitive adhesive layer 2 of the pressure-sensitive adhesive sheet 3 at its outer peripheral portion.

In the case of employing the first configuration, the pressure-sensitive adhesive layer is formed of an energy ray curable pressure-sensitive adhesive, and the area where the protective film forming film is laminated is previously subjected to energy ray irradiation to reduce the tackiness, The adhesive force may be kept high. In order not to irradiate the energy ray only to another region, for example, an energy ray shielding layer may be provided by printing or the like in a region corresponding to another region of the adhesive sheet, and energy ray irradiation may be performed from the substrate side of the adhesive sheet. In the case of employing this configuration, the pressure-sensitive adhesive layer may be used in an uncured state, and the pressure-sensitive adhesive layer may be irradiated with energy rays before the separation step (step (3)) described later to reduce the adhesiveness. The separation process can be smoothly performed by reducing the tackiness.

As shown in FIG. 2, the second structure is such that a separate jig adhesive layer 5 is formed on the pressure sensitive adhesive layer 2 of the protective film forming sheet 10 in a region not overlapping with the protective film forming film 10 . As the jig adhesive layer, an adhesive member composed of a pressure-sensitive adhesive layer, a substrate and a pressure-sensitive adhesive layer, and a double-sided pressure-sensitive adhesive member having pressure-sensitive adhesive layers on both sides of the core can be employed.

The jig adhesive layer is annular (ring-shaped), has a hollow portion (inner opening), and has a size that can be fixed to a jig 7 such as a ring frame.

The pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer of the pressure-sensitive adhesive layer is not particularly limited, and for example, it is preferably made of an acrylic pressure-sensitive adhesive, a rubber pressure-sensitive adhesive, or a silicone pressure-sensitive adhesive.

When a double-sided adhesive member having a pressure-sensitive adhesive layer on both sides of a core material is used as a jig adhesive layer, one pressure-sensitive adhesive layer (a pressure-sensitive adhesive layer laminated on the pressure-sensitive adhesive sheet, hereinafter sometimes referred to as a "pressure-sensitive adhesive layer for lamination" And the other pressure-sensitive adhesive layer (the pressure-sensitive adhesive layer to be attached to the jig, hereinafter sometimes referred to as "fixing pressure-sensitive adhesive layer") may use the same type of pressure-sensitive adhesives or different pressure-sensitive adhesives.

Of these, an acrylic pressure-sensitive adhesive is preferable from the viewpoint of re-releasability from a jig such as a ring frame. The above-mentioned pressure-sensitive adhesives may be used alone or in combination of two or more.

As the base material or core material of the jig adhesive layer, the same materials as described above can be used.

The thickness of the pressure-sensitive adhesive layer of the jig adhesive layer is preferably 2 to 20 占 퐉, more preferably 3 to 15 占 퐉, still more preferably 4 to 10 占 퐉, and the thickness of the base material and core material is preferably 15 to 200 占 퐉 Preferably 30 to 150 mu m, and more preferably 40 to 100 mu m.

3, an interfacial adhesion adjustment layer 6 is formed between the protective film forming film 4 and the pressure-sensitive adhesive layer 2 so as to have the shape of the protective film forming film as it is, . The interfacial adhesion adjustment layer may be a predetermined film or an interfacial adhesion adjustment pressure-sensitive adhesive layer. It is preferable that the interfacial adhesion adjustment pressure-sensitive adhesive layer is formed by irradiating an energy ray curable pressure-sensitive adhesive with an energy ray in advance.

By forming the protective film forming sheet in the first to third structures, the sheet for forming the protective film can be adhered to the jig by the sufficient adhesiveness of the adhesive layer or the jig adhesive layer in the region surrounding the protective film forming film. At the same time, it is possible to control the adhesiveness at the interface between the protective film forming film and the pressure-sensitive adhesive layer or the interfacial adhesion adjusting layer, and to easily pick up a chip to which a protective film-forming film or protective film is adhered.

As shown in Fig. 4, the protective film forming film 4 and the supporting sheet (in Fig. 4, the pressure-sensitive adhesive layer 2 formed on the substrate 1) The jig adhesive layer 5 may be formed on the outer peripheral portion of the surface of the protective film forming film 4. In this case, As the jig adhesive layer, the same materials as described in the second constitution can be used. When the double-sided adhesive member having a pressure-sensitive adhesive layer on both sides of the core is used as the jig adhesive layer, the pressure-sensitive adhesive layer for lamination is laminated with the protective film-forming film.

The thickness of the support sheet is usually 10 to 500 μm, preferably 15 to 300 μm, particularly preferably 20 to 250 μm. When the support sheet is a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed on a substrate, the thickness of the pressure-sensitive adhesive layer is 3 to 50 占 퐉 in the support sheet.

The cover film may be temporarily adhered to the surface opposite to the surface to which the protective film-forming film is attached to the support sheet. The cover film may cover the pressure-sensitive adhesive layer or the jig adhesive layer when the support sheet is an adhesive sheet. The cover film may be the same as the above-mentioned release sheet.

The thickness of the cover film is usually from 5 to 300 mu m, preferably from 10 to 200 mu m, particularly preferably from 20 to 150 mu m.

The protective film-forming film of such a protective film-forming sheet may be a protective film for an adherend. The film for forming a protective film is attached to the back face of a semiconductor wafer for a face-down chip or a semiconductor chip, and has a function of protecting the semiconductor wafer or the semiconductor chip as a substitute for the sealing resin by being cured by appropriate means. In the case where the semiconductor wafer is attached to the semiconductor wafer, the protective film has a function of reinforcing the wafer, so that breakage of the wafer can be prevented.

[Method for producing sheet for forming protective film]

A method of producing a protective film forming sheet will be specifically described with reference to a protective film forming sheet shown in FIG. 1, but the protective film forming sheet of the present invention is not limited to those obtained by such a manufacturing method.

First, a pressure-sensitive adhesive layer is formed on the surface of a substrate to obtain a pressure-sensitive adhesive sheet. The method of forming the pressure-sensitive adhesive layer on the surface of the substrate is not particularly limited.

For example, a pressure-sensitive adhesive is applied and dried on the release sheet (first release sheet) so as to have a predetermined film thickness to form a pressure-sensitive adhesive layer. Subsequently, the pressure-sensitive adhesive sheet is obtained by transferring the pressure-sensitive adhesive layer onto the surface of the substrate. Alternatively, a pressure-sensitive adhesive may be applied directly to the surface of the substrate and then dried to form a pressure-sensitive adhesive layer to obtain a pressure-sensitive adhesive sheet.

As the release sheet, the film exemplified as the above-described base material can be used.

Further, a composition for forming a protective film is applied on another peeling sheet (second peeling sheet) to form a protective film forming film. Then, another release sheet (third release sheet) is laminated on the protective film-forming film to obtain a laminate of the second release sheet / protective film forming film / third release sheet.

Subsequently, the film for forming a protective film is cut in a shape substantially identical to the adherend to be adhered to the protective film-forming film or including the shape of the adherend, and the remaining portion is removed. When the laminate of the second peeling sheet / protective film forming film / third peeling sheet is in the shape of a strip having a long length, the third peeling sheet is not cut so that a plurality of 2 laminated sheet / protective film forming film / third laminated sheet can be obtained.

Then, the protective film-forming film was laminated on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet obtained above, while peeling off the second release sheet from the laminate of the second release sheet / protective film forming film / third release sheet, Layer / protective film-forming film / third release sheet is obtained. Thereafter, the third release sheet is removed to obtain a protective film-forming sheet relating to the embodiment of Fig. 1 of the present invention. Further, the third release sheet functions as the above-described cover film.

[Method of Manufacturing Semiconductor Device]

Next, a method of using the protective film forming sheet according to the present invention will be described by taking as an example the case where the protective film forming sheet of the first constitution shown in Fig. 1 is applied to the semiconductor device manufacturing method.

The adherend to be attached to the protective film forming film may be a silicon wafer or a compound semiconductor wafer such as gallium and arsenic, an organic material substrate such as a glass substrate, a ceramic substrate, or an FPC, or a metal material such as a precision component Goods. In the following description, a silicon wafer is used as an adherend to be adhered to a protective film forming film.

The method for manufacturing a semiconductor device according to the present invention includes a step of attaching a film for forming a protective film of a protective film forming sheet to a semiconductor wafer and obtaining a semiconductor chip (protective film attached chip) having a protective film. Specifically, it includes the following steps (1) to (4).

Step (1): a step of attaching a protective film forming film of a protective film forming sheet to the back surface of a silicon wafer on which a circuit is formed,

Step (2): a step of heating and curing the protective film forming film to obtain a protective film,

Step (3): a step of separating the protective film-forming film or protective film from the supporting sheet,

Step (4): A step of dicing a silicon wafer and a protective film-forming film or protective film.

As described above, when the protective film forming sheet functions as a dicing sheet for supporting the silicon wafer in the dicing step, the step (4) is performed in the order of step (4) from the viewpoint of simplifying the manufacturing process of the semiconductor device. (3) beforehand.

The method for manufacturing a semiconductor device according to the present invention may further include the following step (5) in addition to the steps (1) to (4).

Step (5): A step of laser-printing a film or a protective film for forming a protective film.

The formation of a circuit on the surface of a silicon wafer can be carried out by various methods including a conventionally used method such as an etching method and a lift-off method. Then, the opposite surface (back surface) of the circuit surface of the wafer is ground. The grinding method is not particularly limited, and may be ground by a known means using a grinder or the like. When grinding the back surface, an adhesive sheet called a surface protective sheet is attached to the circuit surface to protect the circuit on the surface. The back side grinding is performed by grinding the circuit side (i.e., the surface protective sheet side) of the wafer with a chuck table or the like, and grinding the back side where no circuit is formed. The thickness of the wafer after grinding is not particularly limited, but is usually about 50 to 500 占 퐉.

Thereafter, if necessary, the crushed layer formed during the back-grinding is removed. The removal of the fractured layer is performed by chemical etching, plasma etching, or the like.

Then, a film for forming a protective film of the protective film forming sheet is attached to the back surface of the wafer (step (1)). Thereafter, the steps (2) to (4) are carried out. The order of the steps (2) to (4) is not particularly limited. For example, the order of the steps (2), (3) and (4), the order of the steps (3), It is preferable to carry out the process in any one of the order of steps (2), (4) and (3). Details of this process are described in detail in JP-A-2002-280329. As an example, the case of carrying out in the order of steps (3), (2) and (4) will be described. The step (5) can be carried out in any order, but in the following description, it is carried out after the step (4).

First, a film for forming a protective film of the protective film forming sheet is pasted on the back surface of a wafer having a circuit on its surface. Then, the support sheet is peeled from the protective film forming film to obtain a laminate of the wafer and the protective film forming film. Then, the protective film forming film is cured to form a protective film on the entire surface of the wafer. More specifically, the protective film forming film is cured by thermal curing. As a result, a protective film made of a hardened resin is formed on the back surface of the wafer, and the strength is improved as compared with the case where only the wafer is used, so that breakage at the time of handling thinned wafer can be reduced. In addition, the thickness uniformity of the protective film is superior to the coating method in which the coating liquid for the protective film is directly applied to the back surface of the wafer or chip.

Subsequently, the laminate of the wafer and the protective film is diced for each circuit formed on the wafer surface. Dicing is performed to cut the wafer and the protective film together. The dicing of the wafer is performed by a conventional method using a dicing sheet. As a result, a chip group having a protective film on the back surface, which is formed on the dicing sheet, is obtained.

Then, the protective film is laser-printed. The laser marking is performed by a laser marking method, and the surface of the protective film is removed by irradiation with laser light to mark the protective film on the protective film.

Finally, a chip having a protective film on the back surface (chip with a protective film) is picked up by a general means such as a collet to obtain a chip with a protective film. Then, a semiconductor device can be manufactured by mounting a chip with a protective film on a predetermined base in a face-down manner. The semiconductor device may also be manufactured by bonding a semiconductor chip having a protective film on its back surface to another member (chip mounting portion) such as a die pad portion or another semiconductor chip. According to the present invention as described above, it is possible to easily form a protective film having high uniformity of thickness on the back surface of a chip, and it becomes difficult to generate a dicing process or a crack after packaging.

When the step (4) is carried out before the step (3) (for example, the steps (2), (4), 3)), the protective film forming sheet can serve as a dicing sheet. In short, it can be used as a sheet for supporting the wafer during the dicing process. In this case, the wafer is adhered to the inner peripheral portion of the protective film forming sheet via the protective film forming film, and the outer peripheral portion of the protective film forming sheet is bonded to another jig such as a ring frame. And dicing is performed.

Example

Hereinafter, the present invention will be described by way of examples, but the present invention is not limited to these examples. <Measurement of Glass Transition Temperature of Cured Product of Epoxy Compound>, <Measurement of Softening Point of Epoxide Compound> and <Reliability Evaluation of Chip with Protective Film> in the following Examples and Comparative Examples were carried out as follows.

<Measurement of glass transition temperature of cured product of epoxy compound>

2 g of 2-phenyl-4, 5-dihydroxymethylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd. 2 PHZ) as a curing agent was added to 100 g of the epoxy compound, and a curing temperature of 160 캜 and a curing time of 120 minutes To cure the epoxy compound.

The cured product of the epoxy compound was cut into an elongated strip having a width of 4.5 mm, a length of 20.0 mm and a thickness of 0.18 mm to prepare a test piece. Next, tan? (Ratio of loss elastic modulus and storage elastic modulus) of the test piece was measured at a frequency of 11 Hz, a temperature raising rate of 3 占 폚 / min in a tensile mode using a viscoelasticity measuring apparatus (DMA Q800 manufactured by TA instruments) &Lt; / RTI &gt; In this temperature range, the temperature at which the tan 隆 shows the maximum value was read to obtain the glass transition temperature (Tg) of the cured product of the epoxy compound.

<Measurement of softening point of epoxy compound>

The softening point of the epoxy compound was measured according to JIS K 2207: 2006 (circulation method). A constant weight ball was placed in the center of the support ring of the water or glycerin bath, and the temperature at which the sample was squeezed by the weight of the ball was measured after raising the bath temperature at a specified rate.

&Lt; Evaluation of reliability of chip with protective film &

(1) Fabrication of chip with protective film

A film for forming a protective film of the protective film forming sheets of Examples and Comparative Examples was applied on a tape mounter (Adwill RAD-3600 F / 12 manufactured by Lin Tex) on the polished surface of a # 2000 polished silicon wafer (200 mm diameter, 280 탆 thick) And heated to 70 [deg.] C. Subsequently, the protective film forming film was cured by heating (130 DEG C, 2 hours), and the protective film forming film and the supporting sheet were separated to obtain a laminated body of a silicon wafer and a protective film.

The protective film side of the silicon wafer was attached to a dicing tape (Adwill D-676H made by Lin Tec Corporation), and a laminate of a silicon wafer and a protective film was diced into a size of 3 mm x 3 mm using a dicing machine (DFD651, Thereby obtaining a chip with a protective film for reliability evaluation.

(2) Evaluation

Then, the chip with the protective film was put in a condition that mimics the process of actually mounting the chip. As a condition of the pre-condition, the chip with the protective film was baked (at 125 ° C for 20 hours), and the moisture was absorbed for 168 hours under the conditions of 85 ° C and 85% RH. &Lt; / RTI &gt;

Twenty-five chips with the protective film were charged into a cold / heat shock apparatus (TSE-11-A manufactured by ESPEC), and a cycle of -65 캜 (holding time: 10 minutes) and 150 캜 (holding time: 10 minutes) .

Thereafter, with respect to the chips with the protective film taken out from the heat and shock apparatus, the presence or absence of lifting, peeling and cracking at the bonding portions of the chip and the protective film was evaluated by a scanning type ultrasonic flaw detector (Hye-Focus manufactured by Hitachi Kenki Fine Tec) I appreciated. The number of peeled chips (number of defective products) was counted when it was judged that peeling was observed in peeled portions of 0.5 mm or more in peeled portions (peeling off and peeling of the joined portions and cracks). The results are shown in Table 2 (number of defective products / number of tests). When the number of defective products is 2 or less, a highly reliable protective film attached chip is obtained.

<Composition for forming protective film>

The components constituting the protective film-forming film are shown below.

Epoxy compound A: 1,1-bis (2,7-diglycidyloxy-1-naphthyl) methane (glass transition temperature of cured product: 326 캜, softening point: 92 캜, melt viscosity: 4.5 dPa 揃 s, Number average molecular weight: 550)

Epoxy Compound B: bisphenol A type epoxy resin (jER828, product of Mitsubishi Chemical Corporation, glass transition temperature of cured product: 180 占 폚, number average molecular weight: 370)

Epoxy compound C: dicyclopentadiene type epoxy resin (Epicron HP-7200 HH made by DIC, glass transition temperature of cured product: 210 占 폚, softening point: 88 占 폚, melt viscosity: 8 dPa 占 s, number average molecular weight: 760)

· Thermal curing agent: dicyandiamide (Asahi Denka Ade Cover Donor 3636 AS)

· Curing accelerator: 2-phenyl-4,5-dihydroxymethylimidazole (Qyazor 2 PHZ manufactured by Shikoku Chemical Industry Co., Ltd.)

Acrylic Polymer A: An acrylic polymer (weight average molecular weight: 270,000, manufactured by Mitsubishi Chemical Corporation) comprising 10 parts by mass of butyl acrylate, 70 parts by mass of methyl methacrylate, 15 parts by mass of 2-hydroxyethyl acrylate and 5 parts by mass of glycidyl methacrylate, Glass transition temperature: -1 캜)

Acrylic Polymer B: An acrylic polymer (weight average molecular weight: 4,400,000, weight average molecular weight: 4,000,000) consisting of 15 parts by weight of butyl acrylate, 65 parts by weight of methyl methacrylate, 15 parts by weight of 2-hydroxyethyl acrylate, and 5 parts by weight of glycidyl methacrylate, Glass transition temperature: -4 캜)

· Inorganic filler: silica filler (fused quartz filler, average particle diameter 8 μm)

Colorant: Carbon black (MA600B made by Mitsubishi Chemical Corporation)

Coupling agent A: Silane coupling agent (Shin-Etsu Chemical Co., Ltd., X-41-1056)

Coupling agent B: Silane coupling agent (KBE-403, Shin-Etsu Chemical Co., Ltd.)

Coupling agent C: Silane coupling agent (KBM-403 manufactured by Shin-Etsu Chemical Co., Ltd.)

(Examples and Comparative Examples)

Each of the above components was compounded in the amounts shown in Table 1 to obtain a composition for forming a protective film. As a release sheet, a polyethylene terephthalate film (SP-PET381031 manufactured by Lin Tec Co., Ltd., thickness: 38 mu m, surface tension less than 30 mN / m, melting point: 200 DEG C or more)

A methyl ethyl ketone solution (solid concentration: 61% by weight) of the composition for the protective film forming layer was coated on the release surface of the release sheet so as to have a thickness of 25 탆 and dried (drying condition: oven at 120 캜 for 3 minutes ) To form a protective film-forming film on the release sheet. Subsequently, another release sheet was laminated on the protective film-forming film, and a laminate having a protective film-forming film held on the release sheet was obtained. Thereafter, one of the release sheets was not die-cut completely, and the other release die and the protective film-forming film were die-cut so as to completely die-cut the laminate to the same size (diameter 200 mm) as the silicon wafer, The film for forming a protective film was circularly cut on the peeling sheet of the protective film forming film and the remaining protective film forming film and the other peeling sheet were removed.

Further, a pressure-sensitive adhesive sheet (Adwill D-676H, manufactured by Lin Tec Co., Ltd.) was prepared as a support sheet.

The protective film-forming film was stuck on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, and die-cut into a concentric circle in accordance with the outer diameter (diameter: 260 mm) of the grooming allowance for the ring frame. Thereafter, the release sheet on the protective film-forming film was peeled off to obtain a protective film-forming sheet in the mode of FIG.

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Epoxy Compound A 5 5 5 5 Epoxy Compound B 30 25 30 25 30 30 The epoxy compound C 5 10 5 10 10 10 Heat curing agent One One One One One One Hardening accelerator One One One One One One Acrylic Polymer A 50 50 50 Acrylic Polymer B 50 50 50 Inorganic filler 100 100 100 100 100 100 coloring agent 3 3 3 3 3 3 Coupling agent A 0.3 0.3 0.3 0.3 0.3 0.3 Coupling agent B 0.2 0.2 0.2 0.2 0.2 0.2 Coupling agent C 0.2 0.2 0.2 0.2 0.2 0.2

unit: Mass part

<Reliability Evaluation of a Chip with a Protective Film> was carried out using the resulting protective film-forming sheet. The results are shown in Table 2.

Reliability evaluation of chip with protective film (defective product / test water) Example 1 0/25 Example 2 0/25 Example 3 0/25 Example 4 0/25 Comparative Example 1 10/25 Comparative Example 2 6/25

The protective film obtained by curing the protective film-forming film of the protective film-forming sheet of the Example exhibited excellent reliability. From these results, it was confirmed that by using the protective film-forming film or the protective film-forming sheet according to the present invention, a chip with a protective film with high reliability was obtained. Therefore, by using the chip with the protective film, a semiconductor device having excellent reliability can be manufactured.

10: Sheet for forming a protective film
1: substrate
2: Pressure-sensitive adhesive layer
3: Support sheet
4: Film for forming a protective film
5: Jig adhesive layer
6: Interfacial adhesion adjustment layer
7: Jig

Claims (6)

A film for forming a protective film for forming a protective film for protecting a semiconductor chip,
A film for forming a protective film containing an epoxy thermosetting component comprising an epoxy compound having a glass transition temperature of 220 ° C or higher. The method according to claim 1,
Wherein the epoxy compound has a softening point of 60 to 110 占 폚. 3. The method according to claim 1 or 2,
A film for forming a protective film containing an acrylic polymer. 4. The method according to any one of claims 1 to 3,
And a thickness of 1 to 100 占 퐉. A sheet for forming a protective film, wherein the protective film-forming film according to any one of claims 1 to 4 is laminated on a support sheet. A manufacturing method of a semiconductor device including the following steps (1) to (4):
Step (1): A step of attaching a film for forming a protective film of a protective film-forming sheet according to claim 5 to an adherend,
Step (2): a step of heating and curing the protective film forming film to obtain a protective film,
Step (3): a step of separating the protective film-forming film or protective film from the supporting sheet,
Step (4): Step of dicing the adherend and the protective film-forming film or protective film.

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