JP6216354B2 - Protective film forming film - Google Patents

Description

  The present invention relates to a protective film-forming sheet capable of efficiently forming a protective film with high adhesive strength on a chip and capable of manufacturing a highly reliable chip with a protective film. In particular, the present invention relates to a protective film forming film used for manufacturing a semiconductor chip mounted by a so-called face down method.

  2. Description of the Related Art In recent years, semiconductor devices have been manufactured using a so-called “face down” mounting method. In the face-down method, a semiconductor chip (hereinafter simply referred to as “chip”) having electrodes such as bumps on a circuit surface is used, and the electrodes are bonded to a substrate. For this reason, the surface (chip back surface) opposite to the circuit surface of the chip may be exposed.

  The exposed back surface of the chip may be protected by an organic film. Conventionally, a chip having a protective film made of an organic film is obtained by applying a liquid resin to the back surface of a wafer by spin coating, drying and curing, and cutting the protective film together with the wafer. However, since the thickness accuracy of the protective film formed in this way is not sufficient, the product yield may be lowered.

  In order to solve the above problem, Patent Document 1 describes a colored wafer back surface protective film containing a thermosetting resin such as an epoxy resin.

JP 2010-199541 A

  The present inventors can increase the strength of a protective film obtained by curing a protective film-forming film and improve the productivity of a chip with a protective film by using an epoxy-based thermosetting component containing a specific compound. In addition, the present inventors have found that a highly reliable chip with a protective film can be manufactured, and have completed the present invention. That is, an object of the present invention is to provide a protective film-forming film that has a high protective film strength, contributes to an improvement in the productivity of the protective film-coated chip, and can obtain a highly reliable chip with a protective film. It is.

（ただし、一般式（Ｉ）において、ＣＲは縮合環式芳香族炭化水素を示し、Ｒ^１は水素原子または炭素数１〜１０のアルキル基を示し、ｍは２〜６の整数を示す。）

（ただし、一般式（ＩＩ）において、ＣＲ^１およびＣＲ^２は縮合環式芳香族炭化水素を示し、これらの縮合環式芳香族炭化水素は同一でも異なっていてもよく、Ｒ^２は二価の炭化水素基を示し、該炭化水素基は置換基を有していてもよく、Ｒ^３は水素原子、炭素数１〜１０のアルキル基、またはグリシジルエーテル基を示し、ｎは１〜３の整数を示し、ｐは０〜１０の整数であり、ｐが０の場合にはＲ^２は単結合を示し、ｑは１〜３の整数を示す。） The present invention includes the following gist.
[1] A protective film-forming film for forming a protective film for protecting a semiconductor chip,
Containing an epoxy-based thermosetting component containing a condensed cyclic aromatic compound having an epoxy group,
The film for protective film formation whose condensed cyclic aromatic compound which has an epoxy group is a compound represented by the following general formula (I) or (II).

(However, in the general formula (I), CR represents a condensed cyclic aromatic hydrocarbon, 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)

(However, in the general formula (II), CR ¹ and CR ² represent fused cyclic aromatic hydrocarbons, and these fused cyclic aromatic hydrocarbons may be the same or different, and R ² is a divalent ring. A hydrocarbon group, which may have a substituent, R ³ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a glycidyl ether group, and n is an integer of 1 to 3 P is an integer of 0 to 10, and when p is 0, R ² represents a single bond and q represents an integer of 1 to ^3. )

[2] The film for forming a protective film according to [1], wherein the condensed ring of the condensed cyclic aromatic compound includes a naphthalene ring.

[3] The protective film-forming film according to [1] or [2], wherein the epoxy equivalent of the condensed cyclic aromatic compound having an epoxy group is 160 to 170 g / eq.

（ただし、Ｒ^４は単結合または二価の炭化水素基を示し、該炭化水素基は置換基を有していてもよい。） [4] The film for forming a protective film according to any one of [1] to [3], wherein the condensed cyclic aromatic compound having an epoxy group is a compound represented by the following general formula (III).

(However, R ⁴ represents a single bond or a divalent hydrocarbon group, and the hydrocarbon group may have a substituent.)

[5] The film for forming a protective film according to any one of [1] to [4], which contains an acrylic polymer.

[6] The film for forming a protective film according to any one of [1] to [5], which has a thickness of 1 to 100 μm.

[7] The protective film-forming film according to any one of [1] to [6], wherein the epoxy thermosetting component includes an epoxy compound having no condensed cyclic aromatic structure.

[8] The content of the condensed cyclic aromatic compound having an epoxy group is 2.5 to 15 parts by mass with respect to 100 parts by mass of the total solid content constituting the protective film-forming film [1] to [7 ] The film for protective film formation in any one of.

[9] A protective film-forming sheet obtained by laminating the protective film-forming film according to any one of [1] to [8] on a support sheet.

[10] A semiconductor device manufacturing method including the following steps (1) to (4):
Step (1): A step of applying the protective film-forming film of the protective film-forming sheet according to [9] above to an adherend,
Step (2): a step of heat-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 and the support sheet, and
Step (4): a 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 highly reliable chip with a protective film can be produced. Further, since the protective film has high strength and is cured in a short time, the productivity of the chip with the protective film can be improved.

The sheet | seat for protective film formation of a 1st aspect is shown. The sheet | seat for protective film formation of a 2nd aspect is shown. The sheet | seat for protective film formation of a 3rd aspect is shown. The sheet | seat for protective film formation of a 4th aspect is shown.

  Hereinafter, the details of the protective film-forming film of the present invention will be described.

[Film for forming a protective film]
A 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-based thermosetting component containing at least a condensed cyclic aromatic compound having an epoxy group. .

Epoxy-based thermosetting component The epoxy-based thermosetting component contains at least a condensed cyclic aromatic compound having an epoxy group, and a combination of a condensed cyclic aromatic compound having an epoxy group and a thermosetting agent is used. preferable. In addition, as the epoxy thermosetting component, a compound having an epoxy group other than the condensed cyclic aromatic compound having an epoxy group (hereinafter, simply referred to as “other epoxy compound”) may be used. .

In the present invention, the condensed cyclic aromatic compound having an epoxy group refers to a condensed cyclic aromatic hydrocarbon having a condensed ring and an aromatic ring, wherein the epoxy group is directly or A compound bonded through an alkoxy group. Although carbon number of condensed cyclic aromatic hydrocarbon is not specifically limited, Preferably it is 8-55, More preferably, it is 12-45, More preferably, it is 16-35.
By containing a condensed cyclic aromatic compound having an epoxy group, the protective film-forming film can be cured in a short time, and the protective film obtained by curing the protective film-forming film can be strengthened. it can. That is, by including the condensed cyclic aromatic compound having an epoxy group, the curability of the protective film-forming film is excellent. As a result, the reliability and productivity of the chip with protective film manufactured using the film for forming a protective film according to the present invention is improved.

（ただし、一般式（Ｉ）において、ＣＲは縮合環式芳香族炭化水素を示し、Ｒ^１は水素原子または炭素数１〜１０のアルキル基を示し、ｍは２〜６の整数を示す。Ｒ^１がアルキル基の場合、その炭素数は１〜６が好ましい。また、ｍは２〜４が好ましい。）

（ただし、一般式（ＩＩ）において、ＣＲ^１およびＣＲ^２は縮合環式芳香族炭化水素を示し、これらの縮合環式芳香族炭化水素は同一でも異なっていてもよく、Ｒ^２は二価の炭化水素基を示し、該炭化水素基は置換基ａを有していてもよく、Ｒ^３は水素原子、炭素数１〜１０のアルキル基、またはグリシジルエーテル基を示し、ｎは１〜３の整数を示し、ｐは０〜１０の整数であり、ｐが０の場合にはＲ^２は単結合を示し、ｑは１〜３の整数を示す。Ｒ^２の炭素数は１〜６が好ましい。また、Ｒ^３がアルキル基の場合、その炭素数は１〜６が好ましい。ｎは１〜２が好ましく、ｐは０〜４が好ましく、ｑは１〜２が好ましい。） Examples of the condensed cyclic aromatic compound having an epoxy group include those in which a glycidyl ether group is bonded to a condensed ring (an epoxy group is bonded via a methoxy group), for example, the following general formula (I) or ( And a compound represented by II).

(In the general formula (I), CR represents a condensed cyclic aromatic hydrocarbon, 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 1} is an alkyl group, the number of carbon atoms is preferably 1-6, and m is preferably 2-4.)

(However, in the general formula (II), CR ¹ and CR ² represent fused cyclic aromatic hydrocarbons, and these fused cyclic aromatic hydrocarbons may be the same or different, and R ² is a divalent ring. Represents a hydrocarbon group, and the hydrocarbon group may have a substituent a, R ³ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a glycidyl ether group, and n represents 1 to 3 P represents an integer of 0 to 10, and when p is 0, R ² represents a single bond, q represents an integer of 1 to ^3. R ² preferably has 1 to 6 carbon atoms. When R ³ is an alkyl group, the number of carbon atoms is preferably 1 to 6. n is preferably 1 to 2, p is preferably 0 to 4, and q is preferably 1 to 2.)

Examples of the substituent a of R ² in the general formula (II) include a phenyl group or a phenyl group having a substituent b. Examples of the substituent b include an alkyl group having 1 to 6 carbon atoms or a glycidyl ether group, and an alkyl group having 1 to 4 carbon atoms is preferable.

  Examples of the condensed ring of the condensed cyclic aromatic compound include a naphthalene ring, an anthracene ring, a phenanthrene ring, or a 3,4-benzopyrene ring. Among these, a naphthalene ring is used from the viewpoint of curability of the protective film-forming film. Is preferred.

（ただし、Ｒ^４は、単結合または二価の炭化水素基を示し、該炭化水素基は置換基を有していてもよい。なお、前記一般式（ＩＩＩ）〜（Ｖ）の化合物を併用する場合、Ｒ^４は同一でも異なっていてもよい。） Specific examples of the compound represented by the general formula (I) or (II) and having a naphthalene ring as a condensed ring include 1,1-bis (2,7-disilane represented by the following general formula (III). Glycidyloxy-1-naphthyl) alkane, 1- (2,7-diglycidyloxy-1-naphthyl) -1- (2-glycidyloxy-1-naphthyl) alkane represented by the following general formula (IV), or A 1,1-bis (2-glycidyloxy-1-naphthyl) alkane represented by the following general formula (V) can be exemplified.

(However, R ⁴ represents a single bond or a divalent hydrocarbon group, and the hydrocarbon group may have a substituent. The compounds of the general formulas (III) to (V) are used in combination. R ⁴ may be the same or different.

（上記式中、炭素に結合する上下方向の結合手は、それぞれナフタレン環に結合し、Ｒ^５およびＲ^６は、それぞれ独立に水素原子、炭素数１〜１０のアルキル基、フェニル基または置換基ｃを有するフェニル基を示す。Ｒ^５およびＲ^６が置換基ｃを有するフェニル基の場合、その置換基ｃとしては、炭素数１〜１０のアルキル基、またはグリシジルエーテル基などが挙げられ、好ましくは水素原子または炭素数１〜６のアルキル基である。Ｒ^５およびＲ^６としては、保護膜形成用フィルムの硬化性の観点から水素原子が特に好ましい。上記式中、ｎは０〜４、好ましくは０〜３の整数であり、さらに好ましくは１である。なお、ｎが０の場合、上記式の構造は単結合を示す。） R ⁴ in the general formulas (III) to (V) is more preferably a divalent hydrocarbon group which may have a substituent represented by the following formula.

(In the above formula, the bonds in the vertical direction bonded to carbon are bonded to the naphthalene ring, and R ⁵ and R ⁶ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a phenyl group, or a substituent. a phenyl group having 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, a glycidyl ether group, and the like. Is a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ⁵ and R ⁶ are particularly preferably a hydrogen atom from the viewpoint of curability of the protective film-forming film, wherein n is 0 to 4, Preferably it is an integer of 0 to 3, more preferably 1. In addition, when n is 0, the structure of the above formula represents a single bond.)

Among the compounds represented by the general formulas (III) to (V), the compound represented by the general formula (III) is preferable from the viewpoint of curability of the protective film-forming film, and the compound represented by the general formula (III) is particularly preferable. A compound in which R ⁴ is methylene (—CH ₂ —) is preferred.

  Moreover, 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 making an epoxy equivalent into the said range, it is excellent in sclerosis | hardenability of the film for protective film formation.

The glass transition temperature of the cured product of the condensed cyclic aromatic compound having an epoxy group is preferably 220 ° C. or higher, more preferably 220 to 350 ° C., further preferably 240 to 345 ° C., and particularly preferably 300 to 330 ° C. . The sclerosis | hardenability of the film for protective film formation can be improved by making the glass transition temperature of the hardened | cured material of the condensed cyclic aromatic compound which has an epoxy group into the said range.
The glass transition temperature of the cured product of the condensed cyclic aromatic compound having an epoxy group can be measured by the following method. To 100 g of the condensed cyclic aromatic compound having an epoxy group, 2 g of 2-phenyl-4,5-dihydroxymethylimidazole (Cureazole 2PHZ, manufactured by Shikoku Kasei Kogyo) is added as a curing agent, a curing temperature of 160 ° C., and a curing time of 120 The condensed cyclic aromatic compound having an epoxy group is cured in minutes. Next, a cured product of the fused cyclic aromatic compound having an epoxy group is cut into a strip shape 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. Then, using a viscoelasticity measuring apparatus (DMA instruments made by TA instruments, DMA Q800), in the tensile mode, the tan δ (ratio of loss elastic modulus to storage elastic modulus) of the test piece was set at a frequency of 11 Hz and a heating rate of 3 ° C. / Minutes, measured at 0 to 350 ° C. in an air atmosphere. The temperature at which tan δ exhibits the maximum value in this temperature range is read and used as the glass transition temperature (Tg) of the cured product of the condensed cyclic aromatic compound having an epoxy group.

  The softening point of the condensed cyclic aromatic compound having an epoxy group is preferably 60 to 110 ° C, more preferably 70 to 100 ° C, particularly preferably 80 to 97 ° C, and particularly preferably 90 to 95 ° C. By setting the softening point of the condensed cyclic aromatic compound having an epoxy group within the above range, the curability of the protective film-forming film can be improved. The softening point of the condensed cyclic aromatic compound having an epoxy group is measured according to JIS K 2207: 2006 (ring and ball method). A ball of a constant weight is placed in the center of a support ring in a water or glycerin bath, the bath temperature is raised at a specified speed, and the temperature at which the sample hangs down by the weight of the ball is measured to obtain the softening point.

  The melt viscosity of the fused cyclic aromatic compound having an epoxy group is preferably 1.0 to 25.0 dPa · s, more preferably more than 2.0 dPa · s and not more than 15.0 dPa · s, still more preferably 2.5. It is -7.0dPa * s. By setting the melt viscosity of the condensed cyclic aromatic compound having an epoxy group within the above range, the curability of the protective film-forming film can be improved. The melt viscosity of the fused cyclic aromatic compound having an epoxy group is a viscosity measured with 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 condensed cyclic aromatic compound having an epoxy group is preferably 200 to 1000, more preferably 300 to 900, still more preferably 400 to 800, and particularly preferably 450 to 750. By setting the number average molecular weight (Mn) of the condensed cyclic aromatic compound having an epoxy group within the above range, the curability of the protective film-forming film can be improved. The number average molecular weight of the condensed cyclic aromatic compound having an epoxy group is a value in terms of polystyrene measured by a gel permeation chromatography (GPC) method.

  The content of the condensed cyclic aromatic compound having an epoxy group is preferably 1 to 20 parts by mass, more preferably 2 to 18 parts by mass, with respect to 100 parts by mass of the total solid content constituting the protective film-forming film. More preferably, it is 2.5-15 mass parts. By making content of the condensed cyclic aromatic compound which has an epoxy group into the said range, sclerosis | hardenability of the film for protective film formation can be improved.

  In the protective film-forming film of the present invention, another epoxy compound can be used in combination with the condensed cyclic aromatic compound having an epoxy group.

Other epoxy compounds As the other epoxy compounds, various conventionally known epoxy compounds having no condensed cyclic aromatic structure can be used. Specifically, bisphenol A diglycidyl ether and hydrogenated products thereof, o-cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenylene skeleton An epoxy compound having two or more functional groups in the molecule, such as a type epoxy resin. These can be used individually by 1 type or in combination of 2 or more types.

  When using another epoxy compound, the content thereof is preferably 5 to 40 parts by mass, more preferably 10 to 35 parts by mass, with respect to 100 parts by mass of the total solid content constituting the protective film-forming film. More preferably, it is 15-30 mass parts. By making content of another epoxy compound into the said range, the adhesiveness with respect to the semiconductor chip of the protective film obtained by hardening | curing the film for protective film formation improves. Moreover, when laminating | stacking the protective film formation film on a support sheet, the peeling force of the film for protective film formation and a support sheet can be controlled, As a result, the transfer defect of the film for protective film formation is prevented.

Thermosetting agent A thermosetting agent functions as a hardening | curing agent with respect to the condensed cyclic aromatic compound which has an epoxy group, and another epoxy compound. A preferable thermosetting agent includes a compound having two or more functional groups capable of reacting with an epoxy group in one molecule. Examples of the functional group include phenolic hydroxyl groups, alcoholic hydroxyl groups, amino groups, carboxyl groups, and acid anhydrides. Of these, phenolic hydroxyl groups, amino groups, or acid anhydrides are preferable, and phenolic hydroxyl groups or amino groups are more preferable.

Specific examples of the phenolic curing agent include polyfunctional phenolic resin, biphenol, novolac type phenolic resin, dicyclopentadiene type phenolic resin, zylock type phenolic resin, or aralkylphenolic resin.
A specific example of the amine curing agent is DICY (dicyandiamide).
These can be used individually by 1 type or in mixture of 2 or more types.

  The content of the thermosetting agent is preferably 0.1 to 500 parts by mass, more preferably 1 to 200 parts by mass with respect to a total of 100 parts by mass of the condensed cyclic aromatic compound having an epoxy group and another epoxy compound. More preferably, it is 2 to 10 parts by mass. By setting the content of the thermosetting agent in the above range, the adhesive property of the protective film obtained by curing the protective film forming film to the semiconductor chip and the suitability of the protective film forming film to the semiconductor wafer are excellent.

In order to adjust the rate of thermal curing of the film for forming a curing accelerator protective film, a curing accelerator may be used. Preferred curing accelerators include tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris (dimethylaminomethyl) phenol; 2-methylimidazole, 2-phenylimidazole, 2-phenyl- Imidazoles such as 4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole; Organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine; And tetraphenylboron salts such as tetraphenylphosphonium tetraphenylborate and triphenylphosphinetetraphenylborate. These can be used individually by 1 type or in mixture of 2 or more types.

  The curing accelerator is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 0.1 parts by mass with respect to 100 parts by mass in total of the condensed cyclic aromatic compound having an epoxy group, another epoxy compound and a thermosetting agent. It is included in an amount of 3 parts by mass. By setting the content of the curing accelerator in the above range, the protective film obtained by curing the protective film-forming film is excellent in adhesiveness to the semiconductor chip even when exposed to high temperature and high humidity, and is severe. High reliability can be achieved even when exposed to reflow conditions.

Energy ray 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-based thermosetting component. In the case where the protective film-forming film contains an energy ray-curable component, the protective film-forming film can be preliminarily cured by energy ray irradiation. The cohesive force of the film-forming film can be increased, and the adhesive force between the protective film-forming film and the support sheet can be reduced. As a result, it becomes easy to separate the chip with a protective film-forming film from the support sheet, and the pickup property of the chip with the protective film-forming film is excellent. The energy ray-curable component may be an energy ray-reactive compound alone as a compound having a reactive double bond group, but it is preferable to use a combination of an energy ray-reactive compound and a photopolymerization initiator. .

Energy ray reactive compounds As energy ray reactive compounds, specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or 1, Examples include acrylate compounds such as 4-butylene glycol diacrylate, 1,6-hexanediol diacrylate, and polyfunctional acrylates containing dicyclopentadiene skeleton, and also oligoester acrylates, urethane acrylate oligomers, epoxy acrylates, polyether acrylates And acrylate compounds having a polymerized structure such as acrylate compounds such as itaconic acid oligomers. Include the relatively low molecular weight. Such a compound has 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, more preferably 2 to 4 parts by mass with respect to 100 parts by mass of the total solid content constituting the protective film-forming film.

By combining the photopolymerization initiator with the photopolymerization initiator energy beam 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 dimethyl ketal, 2, 4-diethylthioxanthone, 1-hydroxycyclohexyl phenyl ketone, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, benzyl, dibenzyl, diacetyl, 1,2-diphenylmethane, 2-hydroxy-2-methyl -1- [4- (1-Methylvinyl) phenyl] propanone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and β-claw Anthraquinone and the like. A photoinitiator can be used individually by 1 type or in combination of 2 or more types.

The content of the photopolymerization initiator is preferably 0.1 to 10 parts by mass, more preferably 1 to 7 parts by mass with respect to 100 parts by mass of the energy ray reactive compound.
If the content of the photopolymerization initiator is less than 0.1 parts by mass, sufficient curability may not be obtained due to insufficient photopolymerization, and if it exceeds 10 parts by mass, a residue that does not contribute to photopolymerization is generated. May cause malfunctions.

The polymer component protective film-forming film may contain a polymer component. The polymer component is added to the protective film-forming film mainly for the purpose of imparting sheet shape maintaining property to the protective film-forming 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 when measured by a gel permeation chromatography method (GPC) method (polystyrene standard). The measurement by such a method is carried out by, for example, using a high-speed GPC device “HLC-8120GPC” manufactured by Tosoh Corporation, a high-speed column “TSK gold column H _XL- H”, “TSK Gel GMH _XL ”, “TSK Gel G2000 H _XL ”. (The above, all manufactured by Tosoh Corporation) are connected in this order, and the detector is used as a differential refractometer at a column temperature of 40 ° C. and a liquid feed rate of 1.0 mL / min.
In addition, for the convenience of distinguishing from the curable polymer mentioned later, a polymer component does not have a hardening functional functional group mentioned later.

  Polymer components include acrylic polymers, polyesters, phenoxy resins (for the purpose of distinguishing from curable polymers described later, limited to those having no epoxy group), polycarbonates, polyethers, polyurethanes, polysiloxanes, rubber-based polymers. A coalescence or the like can be used. In addition, an acrylic urethane resin obtained by reacting a urethane prepolymer having an isocyanate group at a molecular terminal with an acrylic polyol having an hydroxyl group and an acrylic polyol having a combination of two or more of these, Also good. Furthermore, two or more of these may be used in combination, including a polymer in which two or more are bonded.

  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 with respect to 100 parts by mass of the total solid content constituting the protective film-forming film. Part. By making the content of the polymer component in the protective film-forming film within the above range, when various polymer components are combined, the suitability of the protective film-forming film to the adherend can be stably obtained. Becomes easy.

The acrylic polymer polymer component, the acrylic polymer is preferably used. The glass transition temperature (Tg) of the acrylic polymer is preferably in the range of −60 to 50 ° C., more preferably −50 to 40 ° C., and further preferably −40 to 30 ° C. If the glass transition temperature of the acrylic polymer is high, the adhesion of the protective film-forming film to the adherend (semiconductor wafer, etc.) will decrease, making it impossible to transfer to the adherend, or forming a protective film from the adherend after transfer. In some cases, the protective film obtained by curing the protective film or the protective film-forming film peels off. Further, when the glass transition temperature of the acrylic polymer is low, the peeling force between the protective film-forming film and the support sheet is increased, and transfer failure of the protective film-forming film may occur.
The Tg of the acrylic polymer is a value determined from the FOX equation.

  The weight average molecular weight (Mw) of the acrylic polymer is preferably 100,000 to 1,500,000. If the weight average molecular weight of the acrylic polymer is high, the initial adhesiveness of the protective film-forming film may be reduced, and transfer to the adherend may not be possible. Further, when the weight average molecular weight of the acrylic polymer is low, the adhesion between the protective film-forming film and the support sheet is increased, and transfer failure of the protective film-forming film may occur.

  The acrylic polymer contains a (meth) acrylic acid ester monomer or a derivative thereof in at least a constituent monomer. In the present specification, (meth) acryl may be used to include both acrylic and methacrylic.

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

  Examples of the (meth) acrylic acid alkyl ester having 1 to 18 carbon atoms of the alkyl group include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, Pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, (meth) acrylic acid Examples include decyl, lauryl (meth) acrylate, tetradecyl (meth) acrylate, octadecyl (meth) acrylate, and the like.

  Examples of (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, dicyclopentenyl ( Examples thereof include (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, and imide (meth) acrylate.

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

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

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

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

  As the monomer constituting the acrylic polymer, a monomer having a hydroxyl group is preferably used. By using such a monomer, when a hydroxyl group is introduced into the acrylic polymer and the protective film-forming film contains an energy ray-curable component, the compatibility between this and the acrylic polymer is improved. Examples of the monomer having a hydroxyl group include vinyl alcohol and N-methylol (meth) acrylamide in addition to the above-mentioned (meth) acrylic acid ester having a hydroxyl group.

  As the monomer constituting the acrylic polymer, a monomer having a carboxyl group may be used. By using such a monomer, when a carboxyl group is introduced into the acrylic polymer and the protective film-forming film contains an energy ray-curable component, the compatibility between this and the acrylic polymer is improved. To do. Examples of the monomer having a carboxyl group include (meth) acrylic acid, maleic acid, fumaric acid, and itaconic acid in addition to the above (meth) acrylic acid ester having a carboxyl group. However, since the said carboxyl group and the epoxy group in an epoxy-type thermosetting component will react, it is preferable that the usage-amount of the monomer which has a carboxyl group is small.

  In addition, (meth) acrylonitrile, (meth) acrylamide, vinyl acetate, styrene, ethylene, α-olefin and the like may be used as the monomer constituting the acrylic polymer.

  The acrylic polymer may be cross-linked. In the crosslinking, the acrylic polymer before crosslinking has a crosslinkable functional group such as a hydroxyl group, and a crosslinkable functional group is added by adding a crosslinker to the composition for forming a protective film-forming film. And the functional group of the crosslinking agent reacts. By crosslinking the acrylic polymer, the cohesive force of the protective film-forming film can be adjusted. Moreover, the glass transition temperature after thermosetting of the film for protective film formation is controllable by adjusting the crosslinking density of an acrylic polymer. The crosslinking density can be controlled by the addition amount of a crosslinking agent described later.

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

  Examples of organic polyvalent isocyanate compounds include aromatic polyvalent isocyanate compounds, aliphatic polyvalent isocyanate compounds, alicyclic polyvalent isocyanate compounds, trimers of these organic polyvalent isocyanate compounds, and these organic polyvalent isocyanate compounds. Examples thereof include terminal isocyanate urethane prepolymers obtained by reacting with a polyol compound.

  Specifically, as the organic polyvalent isocyanate compound, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane-4,4′- Diisocyanate, diphenylmethane-2,4′-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, dicyclohexylmethane-2,4′-diisocyanate, and lysine isocyanates thereof Examples thereof include polyhydric alcohol adducts.

  Specific examples of organic polyvalent imine compounds include N, N′-diphenylmethane-4,4′-bis (1-aziridinecarboxamide), trimethylolpropane-tri-β-aziridinylpropionate, tetramethylol. Mention may be made of methane-tri-β-aziridinylpropionate and N, N′-toluene-2,4-bis (1-aziridinecarboxamide) triethylenemelamine.

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

  In the present invention, when determining the content of the component constituting the protective film-forming film based on the content of the polymer component, when the polymer component is a cross-linked acrylic polymer, the standard and The content to be used is the content of the acrylic polymer before being crosslinked.

Non-acrylic resin In addition, as a polymer component, polyester, phenoxy resin (for the purpose of distinguishing from the curable polymer described later, limited to those having no epoxy group), polycarbonate, polyether, polyurethane, polysiloxane, rubber system A non-acrylic resin selected from a polymer or a combination of two or more of these may be used. Non-acrylic resins can be used alone or in combination of two or more. Such a resin preferably has a weight average molecular weight of 20,000 to 100,000, and more preferably 20,000 to 80,000.

  The glass transition temperature of the non-acrylic resin is preferably -30 to 150 ° C, more preferably -20 to 120 ° C.

  When a non-acrylic resin is used in combination with the above-mentioned acrylic polymer, when the protective film-forming film is transferred to the adherend using the protective film-forming sheet, the support sheet and the protective film-forming film are Can be more easily peeled off, and the protective film-forming film can follow the transfer surface to prevent the generation of voids.

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

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

  The curable polymer component is a polymer having a curing functional group. The curing functional group is a functional group that can react with each other to form a three-dimensional network structure, and examples thereof include a functional group that reacts by heating and a functional group that reacts by energy rays. The functional functional group may be added to the unit of a continuous structure that becomes the skeleton of the curable polymer component or may be added to the terminal. When the functional functional group is added in the unit of the continuous structure that becomes the skeleton of the curable polymer component, the functional functional group may be added to the side chain or directly to the main chain. Also good. 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 shape maintainability to the protective film-forming film.

An example of a functional group that reacts by heating is 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.
Moreover, it is the polymer similar to the above-mentioned acrylic polymer, Comprising: What polymerized using the monomer which has an epoxy group as a monomer (epoxy group containing acrylic polymer) may be sufficient. Examples of the monomer having an epoxy group include (meth) acrylic acid ester having an epoxy group such as glycidyl (meth) acrylate.
When an epoxy group-containing acrylic polymer is used, its preferred embodiment is the same as that of the acrylic polymer except for the epoxy group.

  When using the curable polymer component which has an epoxy group, you may use together the thermosetting agent mentioned above and a hardening accelerator.

Examples of the functional group that reacts with energy rays include a (meth) acryloyl group. As the curable polymer component having a functional group that reacts with energy rays, an acrylate compound having a polymer structure such as polyether acrylate, and the like having a high molecular weight can be used.
In addition, for example, a raw material polymer having a functional group X such as a hydroxyl group in a side chain, a functional group Y that can react with the functional group X (for example, an isocyanate group when the functional group X is a hydroxyl group) and energy beam irradiation Alternatively, a polymer prepared by reacting a low molecular compound having a functional group that reacts with the above may be used.
In this case, when the raw material polymer corresponds to the above-mentioned acrylic polymer, the preferred mode of the raw material polymer is the same as that of the acrylic polymer.

  When a curable polymer component having a functional group that reacts with energy rays is used, a photopolymerization initiator may be used in the same manner as in the case of using an energy ray curable component.

The film for forming an inorganic filler protective film preferably contains an inorganic filler. By blending an inorganic filler into the protective film-forming film, it becomes easy to adjust the thermal expansion coefficient of the cured protective film, and the thermal expansion coefficient of the cured protective film is optimized for the adherend. By doing so, the reliability of the chip with protective film can be improved. Moreover, it becomes possible to reduce the moisture absorption rate of the protective film after hardening.
Furthermore, by applying laser marking to the protective film, the inorganic filler is exposed at the portion scraped off by the laser beam, and the reflected light diffuses to exhibit a color close to white. Thereby, when the film for protective film formation contains the coloring agent mentioned later, there is an effect that a contrast difference is obtained between the laser marking portion and other portions, and the printing becomes clear.

Preferred inorganic fillers include powders of silica, alumina, talc, calcium carbonate, titanium oxide, iron oxide, silicon carbide, boron nitride, and the like, beads formed by spheroidizing these, single crystal fibers, glass fibers, and the like. Among these, silica filler and alumina filler are preferable. The said inorganic filler can be used individually or in mixture of 2 or more types.
The content of the inorganic filler for obtaining the above-described effects more reliably is preferably 10 to 70 parts by mass, more preferably 40 to 70 parts per 100 parts by mass of the total solid content constituting the protective film-forming film. Part by mass, particularly preferably 50 to 65 parts by mass.

  The average particle size of the inorganic filler is preferably 0.02 to 20 μm, more preferably 0.05 to 10 μm. The average particle diameter of the inorganic filler is the number average particle diameter calculated as an arithmetic average value by measuring the major axis diameters of 20 randomly selected inorganic fillers with an electron microscope.

A colorant can be blended in the colorant protective film-forming film. By blending the colorant, infrared rays and the like can be blocked, so that malfunction of the semiconductor device due to infrared rays and the like generated from surrounding devices can be prevented. In addition, when the protective film is engraved 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 on which a protective film is formed, the product number or the like is usually printed on the surface of the protective film by a laser marking method (a method in which the surface of the protective film is scraped off by laser light and printed). By containing, the contrast difference of the part scraped off with the laser beam of the protective film and the part which is not so is fully obtained, and visibility improves.

As the colorant, organic or inorganic pigments and dyes are used. Among these, black pigments are preferable from the viewpoint of electromagnetic wave and infrared shielding properties. Examples of the black pigment include carbon black, iron oxide, manganese dioxide, aniline black, activated carbon, and the like, but are not limited thereto. Carbon black is particularly preferable from the viewpoint of improving the reliability of the semiconductor device in which the chip with protective film is incorporated. A coloring agent may be used individually by 1 type, and may be used in combination of 2 or more type.
The content of the colorant is preferably 0.1 to 35 parts by mass, more preferably 0.5 to 25 parts by mass, particularly preferably 1 with respect to 100 parts by mass of the total solid content constituting the protective film-forming film. -15 parts by mass.

Coupling agent Improved adhesiveness, adhesion and / or cohesiveness of the protective film to the adherend of the protective film-forming film by using a coupling agent having a functional group that reacts with an inorganic substance and a functional group that reacts with an organic functional group. It may be used to Moreover, the water resistance can be improved by using a coupling agent, without impairing the heat resistance of the protective film obtained by hardening | curing the film for protective film formation. Examples of such coupling agents include titanate coupling agents, aluminate coupling agents, silane coupling agents, and the like. Of these, silane coupling agents are preferred.

As the silane coupling agent, there is a silane coupling agent whose functional group that reacts with the organic functional group is a group that reacts with a functional group of an epoxy thermosetting component, a polymer component, a curable polymer component, or the like. Preferably used.
Examples of such silane coupling agents include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ- (methacryloxy). Propyl) trimethoxysilane, γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-6- (aminoethyl) -γ-aminopropylmethyldiethoxysilane, N -Phenyl-γ-aminopropyltrimethoxysilane, γ-ureidopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, bis (3-triethoxysilylpropyl) tetrasulfane, methyltri Methoxysilane , Methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, and imidazolesilane. These can be used individually by 1 type or in mixture of 2 or more types.

  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 with respect to 100 parts by mass of the total solid content constituting the protective film-forming film. 3 to 5 parts by mass. If the content of the silane coupling agent is less than 0.1 parts by mass, the above effect may not be obtained, and if it exceeds 20 parts by mass, it may cause outgassing.

In addition to the above, various additives may be added to the general-purpose additive protective film-forming film as necessary. Examples of various additives include leveling agents, plasticizers, antistatic agents, antioxidants, gettering agents, chain transfer agents, release agents, and the like.

The protective film-forming film is a composition obtained by mixing an epoxy-based thermosetting component containing a specific compound and each of the above-mentioned components blended as necessary (protective film-forming composition). ). The composition for forming a protective film may be diluted with a solvent in advance, or may be added to the solvent during mixing. Moreover, you may dilute with a solvent at the time of use of the composition for protective film formation.
Examples of such a solvent include ethyl acetate, methyl acetate, diethyl ether, dimethyl ether, acetone, methyl ethyl ketone, acetonitrile, hexane, cyclohexane, toluene, heptane and the like.

  The protective film-forming film has initial adhesiveness and curability, and in an uncured state, is easily adhered by pressing against an adherend at room temperature or under heating. Moreover, you may heat the film for protective film formation, when pressing. Then, after curing, a protective film having high impact resistance can be provided, the adhesive strength is excellent, and sufficient reliability can be maintained even under severe high temperature and high humidity conditions. The protective film-forming film may have a single layer structure or a multilayer structure.

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

[Protective film forming sheet]
The protective film-forming sheet according to the present invention is formed by laminating the above-described protective film-forming film on a support sheet. The protective film forming sheet is affixed to various adherends, and in some cases, the adherend is subjected to required processing such as dicing on the protective film forming sheet. Thereafter, the support film is peeled off by allowing the protective film-forming film to remain adhered to the adherend. That is, it is used in a process including a step of transferring a protective film-forming film from a support sheet to an adherend.

  The shape of the protective film-forming sheet is not limited to a single sheet, but may be a long strip, or may be rolled up. The protective film-forming film can have the same shape as the support sheet. In addition, the protective film forming sheet is prepared in such a manner that the protective film forming film has substantially the same shape as the wafer or can include the shape of the wafer, and has a larger size than the protective film forming film. It may have a pre-molded configuration laminated on the support sheet.

  Examples of the support sheet include a release sheet, and an adhesive sheet described later can also be used.

  As the release sheet, for example, polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyvinyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate film, polybutylene terephthalate film, Polyurethane film, ethylene vinyl acetate copolymer film, ionomer resin film, ethylene / (meth) acrylic acid copolymer film, ethylene / (meth) acrylic acid ester copolymer film, polystyrene film, polycarbonate film, polyimide film, fluorine A resin film or the like is used. These crosslinked films are also used. Furthermore, these laminated films may be sufficient.

  The surface tension of the surface of the release sheet that contacts the protective film-forming film is preferably 40 mN / m or less, more preferably 37 mN / m or less, and 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 the material, and can also be obtained by applying a release agent to the surface of the release sheet and performing a release treatment. .

  As the release agent used for the release treatment, alkyd, silicone, fluorine, unsaturated polyester, polyolefin, wax, and the like are used. In particular, alkyd, silicone, and fluorine release agents are heat resistant. This is preferable.

  In order to release the surface of a film or the like as a substrate of a release sheet using the above release agent, the release agent can be used without any solvent, or can be diluted or emulsified in a solvent to obtain a gravure coater, Mayer bar coater, air knife coater. The release sheet coated with a release coater may be applied at room temperature or under heating, or may be cured with an electron beam to form a release agent layer.

  Further, the surface tension of the release sheet may be adjusted by laminating films by wet lamination, dry lamination, hot melt lamination, melt extrusion lamination, coextrusion processing, or the like. That is, a film in which the surface tension of at least one surface is within a preferable range as the surface in contact with the protective film-forming film of the release sheet described above is such that the surface is in contact with the protective film-forming film. Alternatively, a laminate laminated with another film may be manufactured and used as a release sheet.

  When required processing such as dicing is performed on the adherend on the protective film-forming sheet, it is preferable to use a pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed on a substrate as a support sheet. In this embodiment, the protective film-forming film is laminated on the pressure-sensitive adhesive layer provided on the support sheet. As a base material of an adhesive sheet, said film illustrated as a peeling sheet is mentioned. The pressure-sensitive adhesive layer may be a weakly-adhesive layer having an adhesive strength that can peel off the protective film-forming film, or an energy-ray-curing layer that decreases in adhesive strength when irradiated with energy rays. May be. The pressure-sensitive adhesive layer includes various conventionally known pressure-sensitive adhesives (for example, rubber-based, acrylic-based, silicone-based, urethane-based, vinyl ether-based general-purpose pressure-sensitive adhesives, pressure-sensitive adhesives, energy ray-curable pressure-sensitive adhesives, A thermal expansion component-containing pressure-sensitive adhesive or the like).

  When the configuration of the protective film forming sheet is such a configuration, when the protective film forming sheet functions as a dicing sheet for supporting the adherend in the dicing step, the protective film forming sheet is provided between the support sheet and the protective film forming film. Adhesiveness is maintained and the effect of suppressing that the chip | tip with a film for protective film formation peels from a support sheet in a dicing process is acquired. When the protective film forming sheet functions as a dicing sheet for supporting the adherend in the dicing process, there is no need to dice by separately attaching a dicing sheet to the wafer with the protective film forming film in the dicing process, The manufacturing process of the semiconductor device can be simplified.

  In the case where the protective film forming sheet has a pre-formed configuration, the protective film forming sheet may have the following first, second, or third configuration. Hereinafter, each structure of the protective film forming sheet 10 will be described with reference to FIGS. In addition, in FIGS. 1-3, the structure which uses an adhesive sheet as a support sheet is shown.

  A 1st structure is a structure by which the adhesive sheet 3 in which the adhesive layer 2 was formed on the base material 1 was formed so that peeling was possible on the single side | surface of the film 4 for protective film formation, as shown in FIG. When the first configuration is adopted, the protective film forming sheet 10 is attached to the jig 7 by the adhesive layer 2 of the adhesive sheet 3 at the outer peripheral portion thereof.

  In the case of adopting the first configuration, the pressure-sensitive adhesive layer is composed of an energy ray-curable pressure-sensitive adhesive, and the region where the protective film-forming film is laminated is irradiated with energy rays in advance to reduce the adhesiveness. On the other hand, other regions may be maintained with high adhesive strength without being irradiated with energy rays. In order not to perform energy beam irradiation only in other regions, for example, an energy beam shielding layer is provided by printing or the like in a region corresponding to another region of the pressure-sensitive adhesive sheet, and energy beam irradiation is performed from the base material side of the pressure-sensitive adhesive sheet. Just do it. Moreover, when this structure is adopted, the pressure-sensitive adhesive layer is used in an uncured state, and the pressure-sensitive adhesive layer is irradiated with energy rays before the separation step (step (3)) to be described later, thereby reducing the adhesiveness. May be. By reducing the adhesiveness, the separation process can be carried out smoothly.

  As shown in FIG. 2, the second configuration is a configuration in which a jig adhesive layer 5 is separately provided on the pressure-sensitive adhesive layer 2 of the protective film forming sheet 10 in a region that does not overlap with the protective film forming film 10. . As a jig | tool adhesion layer, the adhesive member which consists of an adhesive layer single-piece | unit, the adhesive member comprised from a base material and an adhesive layer, and the double-sided adhesive member which has an adhesive layer on both surfaces of a core material are employable.

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

Although it does not restrict | limit especially as an adhesive which forms the adhesive layer of a jig | tool adhesion layer, For example, it is preferable to consist of an acrylic adhesive, a rubber-type adhesive, or a silicone adhesive.
When a double-sided pressure-sensitive adhesive member having pressure-sensitive adhesive layers on both sides of the core material is used as a jig adhesive layer, one pressure-sensitive adhesive layer of the jig adhesive layer (pressure-sensitive adhesive layer laminated with the pressure-sensitive adhesive sheet, hereinafter referred to as “for lamination”) The pressure-sensitive adhesive layer ”) and the other pressure-sensitive adhesive layer (the pressure-sensitive adhesive layer affixed to the jig, sometimes referred to as“ fixing pressure-sensitive adhesive layer ”below) are the same type. An adhesive may be used, or a different adhesive may be used.
Among these, an acrylic adhesive is preferable from the viewpoint of removability from a jig such as a ring frame. In addition, the said adhesive may be used independently or may be used in mixture of 2 or more types.

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

  The thickness of the pressure-sensitive adhesive layer of the jig adhesive layer is preferably 2 to 20 μm, more preferably 3 to 15 μm, still more preferably 4 to 10 μm, and the thickness of the base material or the core material is preferably 15 to 200 μm. More preferably, it is 30-150 micrometers, More preferably, it is 40-100 micrometers.

  As shown in FIG. 3, the third configuration includes an interface adhesion adjusting layer 6 having a shape that can completely include the shape of the protective film-forming film between the protective film-forming film 4 and the pressure-sensitive adhesive layer 2. This is a configuration provided. The interface adhesion adjusting layer may be a predetermined film or an interface adhesion adjusting pressure-sensitive adhesive layer. The interfacial adhesion-adjusting pressure-sensitive adhesive layer is preferably a layer obtained by previously irradiating an energy ray-curable pressure-sensitive adhesive and curing it.

  By forming the protective film forming sheet in the first to third configurations, the protective film is formed in the region surrounding the protective film forming film due to sufficient adhesiveness of the adhesive layer or the jig adhesive layer. The sheet can be bonded to a jig. At the same time, the adhesiveness at the interface between the protective film-forming film and the pressure-sensitive adhesive layer or the interfacial adhesion adjusting layer can be controlled to facilitate the pickup of the protective film-forming film or the chip to which the protective film is fixed.

  When the protective film forming sheet does not have a pre-molded configuration, that is, as shown in FIG. 4, the protective film forming film 4 and the support sheet (in FIG. 4, the pressure-sensitive adhesive layer 2 is formed on the substrate 1. When the adhesive sheet 3) has the same shape, a jig adhesive layer 5 may be provided on the outer peripheral portion of the surface of the protective film forming film 4. As the jig adhesive layer, the same one as described in the second configuration can be used. In addition, when using the double-sided adhesive member which has an adhesive layer on both surfaces of a core material as a jig | tool adhesion layer, the adhesive layer for lamination | stacking is laminated | stacked with the film for protective film formation.

  The thickness of the support sheet is usually 10 to 500 μm, preferably 15 to 300 μm, and particularly preferably 20 to 250 μm. In the case where the support sheet is a pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive layer is formed on a substrate, 3 to 50 μm in the support sheet is the thickness of the pressure-sensitive adhesive layer.

  A cover film may be temporarily attached to the surface opposite to the surface to be attached to the support sheet of the protective film-forming film. The cover film may cover the pressure-sensitive adhesive layer when the support sheet is a pressure-sensitive adhesive sheet or the jig adhesive layer. The same cover film as the above-described release sheet can be used.

  The film thickness of the cover film is usually about 5 to 300 μm, preferably about 10 to 200 μm, and particularly preferably about 20 to 150 μm.

  Such a protective film forming film of the protective film forming sheet can be used as a protective film of an adherend. The protective film-forming film is affixed to the back surface of the face-down chip semiconductor wafer or semiconductor chip, and is cured by an appropriate means to have a function of protecting the semiconductor wafer or semiconductor chip as an alternative to the sealing resin. When pasted on a semiconductor wafer, the protective film has a function of reinforcing the wafer, so that damage to the wafer can be prevented.

[Method for producing protective film-forming sheet]
The method for producing a protective film-forming sheet will be specifically described by taking the protective film-forming sheet shown in FIG. 1 as an example, but the protective film-forming sheet of the present invention is limited to that obtained by such a production method. Not.

First, an adhesive layer is formed on the surface of a substrate to obtain an adhesive sheet. The method for providing the pressure-sensitive adhesive layer on the surface of the substrate is not particularly limited.
For example, the pressure-sensitive adhesive is applied on the release sheet (first release sheet) so as to have a predetermined film thickness and dried to form the pressure-sensitive adhesive layer. Subsequently, an adhesive sheet can be obtained by transferring an adhesive layer to the surface of a substrate. Alternatively, the pressure-sensitive adhesive sheet can be obtained by directly applying and drying the pressure-sensitive adhesive on the surface of the substrate to form a pressure-sensitive adhesive layer.
As a release sheet, the film illustrated as a base material mentioned above can be used.

  Moreover, the composition for protective film formation is apply | coated on another peeling sheet (2nd peeling sheet), and the film for protective film formation is formed. Next, another release sheet (third release sheet) is laminated on the protective film-forming film to obtain a laminate of second release sheet / protective film-forming film / third release sheet.

  Next, the protective film-forming film is cut into a shape that can substantially include the shape of the adherend to be adhered to the protective film-forming film or the shape of the adherend, and the remaining portion is removed. When the laminate of the second release sheet / protective film forming film / third release sheet is a long strip-like body, the third release sheet is not cut, so that the long third release sheet A laminate of a plurality of second release sheets / protective film-forming films / third release sheets that are continuously held in the substrate can be obtained.

  And, on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet obtained above, the protective film-forming film was peeled off while peeling the second release sheet from the laminate of the second release sheet / protective film-forming film / third release sheet. Lamination is performed to obtain a laminate composed of the base material / adhesive layer / protective film forming film / third release sheet. Then, the sheet | seat for protective film formation which concerns on the aspect of FIG. 1 of this invention is obtained by removing a 3rd peeling sheet. The third release sheet functions as the above cover film.

[Method for Manufacturing Semiconductor Device]
Next, a method for 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 having the first configuration shown in FIG. 1 is applied to a method for manufacturing a semiconductor device.

  The adherend adhered to the protective film-forming film may be a silicon wafer, a compound semiconductor wafer such as gallium / arsenic, a glass substrate, a ceramic substrate, an organic material substrate such as an FPC, or a precision component. Various articles such as metal materials can be listed. In the following description, an example in which a silicon wafer is used as an adherend to be attached to the protective film forming film will be described.

A manufacturing method of a semiconductor device according to the present invention includes a step of attaching a protective film forming film of the protective film forming sheet to a semiconductor wafer to obtain a semiconductor chip having a protective film (chip with protective film). Specifically, the following steps (1) to (4) are included.
Step (1): A step of attaching a protective film-forming film of the protective film-forming sheet to the back surface of the silicon wafer having a circuit formed on the front surface,
Step (2): Step of heat-curing the protective film-forming film to obtain a protective film Step (3): Step of separating the protective film-forming film or protective film and the support sheet, and
Step (4): A step of dicing the silicon wafer and the 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 process, the process (4) is performed from the viewpoint of simplifying the manufacturing process of the semiconductor device. It is preferable to carry out before the step (3).

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 on the protective film-forming film or the protective film.

  A circuit can be formed on the surface of the silicon wafer by various methods including conventionally used methods such as an etching method and a lift-off method. Next, the opposite surface (back surface) of the circuit surface of the wafer is ground. The grinding method is not particularly limited, and grinding may be performed by a known means using a grinder or the like. At the time of back surface grinding, an adhesive sheet called a surface protective sheet is attached to the circuit surface to protect the circuit on the surface. In the back surface grinding, the circuit surface side (that is, the surface protection sheet side) of the wafer is fixed by a chuck table or the like, and the back surface side on which no circuit is formed is ground by a grinder. The thickness of the wafer after grinding is not particularly limited, but is usually about 50 to 500 μm.

  Thereafter, if necessary, the crushed layer generated during back grinding is removed. The crushed layer is removed by chemical etching, plasma etching, or the like.

  Next, the protective film-forming film of the protective film-forming sheet is attached to the back surface of the wafer (step (1)). Thereafter, steps (2) to (4) are performed. Although the order of process (2)-(4) is not specifically limited, For example, order of process (2), (3), (4), order of process (3), (2), (4) or process ( It is preferable to carry out in any one of the order of 2), (4), and (3). Details of this process are described in detail in JP-A-2002-280329. As an example, a case where the steps (3), (2), and (4) are performed in this order will be described. In addition, although process (5) can be performed in arbitrary orders, in the following description, it is performed after process (4).

  First, the protective film-forming film of the protective film-forming sheet is attached to the back surface of the wafer having a circuit formed on the front surface. Next, the support sheet is peeled from the protective film forming film to obtain a laminate of the wafer and the protective film forming film. Next, the protective film-forming film is cured, and a protective film is formed on the entire surface of the wafer. Specifically, the protective film-forming film is cured by thermosetting. As a result, a protective film made of a cured resin is formed on the back surface of the wafer, and the strength is improved as compared with the case of the wafer alone, so that damage during handling of the thinned wafer can be reduced. In addition, the thickness of the protective film is excellent compared to a coating method in which a coating liquid for the protective film is directly applied to the back surface of the wafer or chip.

  Next, the laminated body of the wafer and the protective film is diced for each circuit formed on the wafer surface. Dicing is performed so as to cut both the wafer and the protective film. The wafer is diced by a conventional method using a dicing sheet. As a result, a chip group that has been separated on the dicing sheet and that has a protective film on the back surface is obtained.

  Next, laser printing is performed on the protective film. Laser printing is performed by a laser marking method, and the surface of the protective film is scraped off by laser light irradiation to mark a product number or the like on the protective film.

  Finally, a chip having a protective film (chip with a protective film) is picked up by a general-purpose means such as a collet to obtain a chip with a protective film. Then, the semiconductor device can be manufactured by mounting the chip with protective film on a predetermined base by the face-down method. Further, a semiconductor device can be manufactured by adhering a semiconductor chip having a protective film on the back surface to another member (on the chip mounting portion) such as a die pad portion or another semiconductor chip. According to the present invention as described above, a protective film having high thickness uniformity can be easily formed on the back surface of the chip, and cracks after the dicing process and packaging are less likely to occur.

  In addition, after affixing the protective film-forming film of the protective film-forming sheet to the back surface of the wafer, the step (4) is performed before the step (3) (for example, the steps (2), (4), When performing in order of (3)), the protective film forming sheet can serve as a dicing sheet. That is, it can be used as a sheet for supporting the wafer during the dicing process. In this case, the wafer is attached 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 joined to another jig such as a ring frame, The protective film forming sheet affixed to the wafer is fixed to the apparatus, and dicing is performed.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these Examples. In the following examples or comparative examples, <Reliability evaluation of chip with protective film> was performed as follows.

<Reliability evaluation of chip with protective film>
(1) Manufacture of chip with protective film The protective film forming film of the protective film forming sheet of Example and Comparative Example was mounted on a polished surface of a # 2000 polished silicon wafer (200 mm diameter, 280 μm thick) as a tape mounter (Lintec). It was affixed while heating to 70 ° C. by Adwill RAD-3600F / 12). Next, the protective film-forming film was cured by heating (130 ° C., 2 hours), and the protective film-forming film and the support sheet were separated to obtain a laminate of the silicon wafer and the protective film.

  Attach the protective film side of the silicon wafer to dicing tape (Adwill D-676H manufactured by Lintec) and use a dicing machine (DFD651 manufactured by Disco) to make the laminate of the silicon wafer and protective film 3 mm x 3 mm size A chip with a protective film for reliability evaluation was obtained by dicing.

(2) Evaluation And it put into the precondition which imitated the process in which the chip with a protective film is actually mounted. As preconditioning conditions, the chip with protective film was baked (125 ° C, 20 hours), absorbed for 168 hours under conditions of 85 ° C and 85% RH, and immediately after removal, IR reflow with preheating 160 ° C and peak temperature 260 ° C Three passes through the furnace.

  Twenty-five chips with protective film were put into a thermal shock apparatus (TSE-11-A made by ESPEC), and a cycle of -65 ° C. (holding time: 10 minutes) and 150 ° C. (holding time: 10 minutes) was performed 1000 times. Repeated.

  After that, for the chip with a protective film taken out from the thermal shock device, a scanning ultrasonic flaw detector (Hye-Focus made by Hitachi Construction Machinery Finetech) And it evaluated by cross-sectional observation. The case where peeling of a width of 0.5 mm or more is observed at the joint between the chip and the protective film is peeled off (the joint is lifted / peeled and cracked) The number (number of defective products) was counted. The results are shown in Table 2 (number of defective products / number of tests). If the number of defective products was 2 or less, it was evaluated that a highly reliable chip with a protective film was obtained.

<Composition for protective film formation>
Each component which comprises the film for protective film formation is shown below.
Condensed cyclic aromatic compound having an epoxy group: 1,1-bis (2,7-diglycidyloxy-1-naphthyl) methane (glass transition temperature of cured product: 326 ° C., softening point: 92 ° C., melt viscosity : 4.5 dPa · s, number average molecular weight: 550)
Epoxy compound A: bisphenol A type epoxy resin (JER828 manufactured by Mitsubishi Chemical, glass transition temperature of cured product: 180 ° C., number average molecular weight: 370)
Epoxy compound B: dicyclopentadiene type epoxy resin (DIC made Epicron HP-7200HH, glass transition temperature of cured product: 210 ° C., softening point: 88 ° C., melt viscosity: 8 dPa · s, number average molecular weight: 760)
-Thermosetting agent: Dicyandiamide (Asahi Denka Adecover Donor 3636AS)
Curing accelerator: 2-phenyl-4,5-dihydroxymethylimidazole (Curesol 2PHZ, manufactured by Shikoku Chemicals)
Acrylic polymer A: an acrylic polymer 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 (weight average molecular weight: 270,000, (Glass transition temperature: -1 ° C)
-Acrylic polymer B: acrylic polymer (weight average molecular weight: 440,000, consisting of 15 parts by mass of butyl acrylate, 65 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: -4 ° C)
Inorganic filler: Silica filler (fused quartz filler, average particle size 8 μm)
・ Coloring agent: Carbon black (Mitsubishi Chemical MA600B)
・ Coupling agent A: Silane coupling agent (X-41-1056 manufactured by Shin-Etsu Chemical Co., Ltd.)
・ Coupling agent B: Silane coupling agent (KBE-403, manufactured by Shin-Etsu Chemical Co., Ltd.)
Coupling agent C: Silane coupling agent (Shin-Etsu Chemical KBM-403)

(Examples and Comparative Examples)
The above components were blended in the amounts shown in Table 1 to obtain a protective film forming composition. In addition, a polyethylene terephthalate film (SP-PET 381031, manufactured by Lintec Corporation, thickness 38 μm, surface tension less than 30 mN / m, melting point 200 ° C. or higher) was prepared as a release sheet.
A methyl ethyl ketone solution (solid concentration: 61% by weight) of the composition for forming a protective film is applied onto the release treatment surface of the release sheet so as to have a thickness of 25 μm and dried (drying condition: 120 ° C. in an oven). 3 minutes) to form a protective film-forming film on the release sheet. Next, another release sheet was laminated on the protective film-forming film to obtain a laminate in which the protective film-forming film was sandwiched between the release sheets. Thereafter, the laminate is die-cut to the same size as the silicon wafer (diameter 200 mm) so that one release sheet is not completely die-cut and the other release sheet and the protective film-forming film are completely die-cut. The protective film-forming film punched in a circular shape was left on one release sheet, and the remaining protective film-forming film and the other release sheet were removed.

  In addition, an adhesive sheet (Adwill D-676H manufactured by Lintec Corporation) was prepared as a support sheet.

  The film for forming a protective film was stuck on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, and die-cut concentrically according to the outer diameter (diameter 260 mm) of the margin for the ring frame. Thereafter, the release sheet on the protective film-forming film was peeled off to obtain the protective film-forming sheet of the embodiment shown in FIG.

  <Reliability evaluation of chip with protective film> was performed using the obtained protective film-forming sheet. The results are shown in Table 2.

  The protective film which hardened | cured the film for protective film formation of the sheet | seat for protective film formation of an Example showed the outstanding reliability. From this result, it was confirmed that a highly reliable chip with a protective film can be obtained by using the protective film-forming film or the protective film-forming sheet according to the present invention. Therefore, a semiconductor device having excellent reliability can be manufactured by using the chip with protective film.

DESCRIPTION OF SYMBOLS 10: Sheet | seat for protective film formation 1: Base material 2: Adhesive layer 3: Support sheet 4: Film for protective film formation 5: Jig adhesion layer 6: Interface adhesion adjustment layer 7: Jig

Claims (9)

A protective film forming film for forming a protective film for protecting a semiconductor chip,
Containing an epoxy-based thermosetting component containing a condensed cyclic aromatic compound having an epoxy group and an acrylic polymer;
The condensed cyclic aromatic compound having an epoxy group is a compound represented by the following general formula (I) or (II):
The content of the acrylic polymer, Ri 15 to 40 parts by mass der the total solid content 100 parts by mass constituting the protective film forming film,
2.5 to 15 parts by mass der Ru protection layer formation film with respect to the total solid content 100 parts by mass of content, constituting the protective film formation film of condensed cyclic aromatic compound having an epoxy group.

(However, in the general formula (I), CR represents a condensed cyclic aromatic hydrocarbon, 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)

(However, in the general formula (II), CR ¹ and CR ² represent fused cyclic aromatic hydrocarbons, and these fused cyclic aromatic hydrocarbons may be the same or different, and R ² is a divalent ring. A hydrocarbon group, which may have a substituent, R ³ represents a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, or a glycidyl ether group, and n is an integer of 1 to 3 P is an integer of 0 to 10, and when p is 0, R ² represents a single bond and q represents an integer of 1 to ^3. )   The film for forming a protective film according to claim 1, wherein the condensed ring of the condensed cyclic aromatic compound contains a naphthalene ring.   The protective film-forming film according to claim 1 or 2, wherein an epoxy equivalent of the condensed cyclic aromatic compound having an epoxy group is 160 to 170 g / eq. The film for forming a protective film according to any one of claims 1 to 3, wherein the condensed cyclic aromatic compound having an epoxy group is a compound represented by the following general formula (III).

(However, R ⁴ represents a single bond or a divalent hydrocarbon group, and the hydrocarbon group may have a substituent.) Contains a silane coupling agent,
The content of the silane coupling agent is 0.1 to 20 parts by mass with respect to 100 parts by mass of the total solid content constituting the protective film forming film. the film.   The film for forming a protective film according to any one of claims 1 to 5, having a thickness of 1 to 100 µm.   The film for protective film formation in any one of Claims 1-6 in which an epoxy-type thermosetting component contains the epoxy compound which does not have a condensed cyclic aromatic structure. Protective film forming film according to any one of claims 1 to 7, formed by stacking on the support sheet for forming a protective film sheet. A method of manufacturing a semiconductor device including the following steps (1) to (4);
Step (1): A step of attaching the protective film-forming film of the protective film-forming sheet according to claim 8 to an adherend,
Step (2): a step of heat-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 and the support sheet, and
Step (4): a step of dicing the adherend and the protective film-forming film or protective film.

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