JP4805203B2 - Chip protection film - Google Patents

Description

  The present invention relates to a film for protecting a chip that can efficiently form a protective film on the back surface of a semiconductor chip and that can improve the manufacturing efficiency of the chip. In particular, the present invention is mounted by a so-called face-down method. The present invention relates to a film for protecting a chip used for manufacturing a semiconductor chip.

  In recent years, semiconductor devices have been manufactured using a so-called face-down mounting method. In the face-down method, a chip in which convex portions called bumps are formed on the circuit surface side of the chip is used, and the convex portions on the circuit surface side are connected to the base.

Such a semiconductor device is generally manufactured through the following steps.
(A) A circuit is formed on the surface of the semiconductor wafer by an etching method or the like, and bumps are formed at predetermined positions on the circuit surface.
(B) The back surface of the semiconductor wafer is ground to a predetermined thickness.
(C) The back surface of the semiconductor wafer is fixed to a dicing sheet stretched on the ring frame, and a semiconductor chip is obtained by cutting and separating each circuit with a dicing saw.
(D) A semiconductor chip is picked up and mounted on a predetermined base by a face-down method, and if necessary, resin sealing or resin coating is applied to the back surface of the chip to obtain a semiconductor device.

The resin sealing is performed by a potting method in which an appropriate amount of resin is dropped and cured on a chip, a molding method using a mold, or the like. However, it is difficult to drop an appropriate amount of resin by the potting method. In the mold method, it is necessary to clean the mold, and the equipment cost and operation become expensive. Furthermore, since it is difficult for the above resin coating to uniformly apply an appropriate amount of resin, quality may vary.
Therefore, there is a demand for the development of a technique that can easily form a highly uniform protective film on the back surface of the chip.

In the back grinding in the above step (b), fine streak scratches are formed on the back surface of the chip by mechanical grinding. This minute scratch may cause cracks after the (c) dicing step or packaging. For this reason, conventionally, chemical etching for removing minute scratches may be necessary after mechanical grinding. However, chemical etching necessitates equipment and operation costs as well as the cost increase.
Therefore, even if minute scratches are formed on the back surface of the chip by mechanical grinding, there is a demand for development of a technique that eliminates the adverse effects caused by such scratches.

In order to solve this problem, a highly uniform protective film can be easily formed on the back surface of the chip, and even if minute scratches are formed on the back surface of the chip by mechanical grinding, the adverse effects caused by such scratches can be eliminated. A process and a film for chip protection used in this process have been proposed (Patent Documents 1 to 3).
JP 2004-214288 A JP 2004-260190 A JP 2004-331728 A

  In the above process, a curable protective film forming layer is formed on the wafer by applying a chip protection film on the wafer and peeling off the release sheet. The curable protective film forming layer is cured by heating or the like to become a protective film, and a product number or the like is marked on the protective film. Thereafter, the wafer having the protective film is fixed on a dicing sheet, and dicing and pick-up are performed. As a marking method, a laser marking method is generally used in which the surface of the protective film is scraped off by laser light irradiation.

However, in this process, when the chip protection film is applied to the back surface of the wafer and cured, the protective film contracts and the wafer may be warped. When warping occurs, there are problems such that the wafer cannot be stored in the cassette, and the laser beam is not focused when performing laser marking, and marking cannot be performed with high accuracy.
In view of such conventional techniques, the present invention provides a chip protection film that does not warp the wafer and is excellent in laser mark recognizability even when applied to the back surface of the wafer and cured. It is an issue.

  As a result of intensive studies on the above problems, the present inventors have used a specific polyamide-based block copolymer and an epoxy resin in combination with the polymer component, and contain silica and a dye or pigment as essential components, and According to the curable protective film forming layer in which the ratio of the content of the polymer component and the content of silica is set in a specific range, a film for chip protection that can suppress warpage of the wafer and has excellent laser mark recognizability. It was found that it can be obtained.

The present invention has been completed by further study based on this finding, and provides the following chip protecting films (1) to (4).
(1) A chip protection film used for manufacturing a semiconductor chip mounted by a face-down method, wherein the chip protection film has a curable protective film forming layer, and the curable protective film formed layer is adhered to the back surface of the circuit forming surface of the wafer, in the chip protection film used to chip the wafer with the protective film by dicing the wafer with a protective film after curing, (a) phenol Containing a polyamide-based block copolymer formed from a functional hydroxyl group-containing aromatic polyamide oligomer and a polybutadiene / acrylonitrile copolymer, (B) an epoxy resin, (C) silica, (D) a dye and / or a pigment as essential components and will be, (a) + (B) ratio is the mass ratio of the content of the content and (C) of [(a) + (B)] / (C) = 0.15 to Chip protection film characterized by having a 2.0 in a range of curable protective film forming layer.
(2) The ratio of the content of (A) and the content of (B) is in a mass ratio of (A) / (B) = 0.2 to 2.0 (1) The film for chip protection as described in 2.
(3) The chip protective film as described in (1) or (2), wherein the average particle diameter of (C) silica is in the range of 0.1 to 5 μm.
(4) The film for protecting a chip according to any one of (1) to (3), which has a curable protective film-forming layer on a release sheet.

  The film for chip protection of the present invention has excellent adhesion to the backside of the wafer, can suppress the warpage of the wafer when cured after bonding, and this curing improves mounting reliability and laser mark recognition. Can also form an excellent protective film.

Next, the film for protecting a chip of the present invention will be described with reference to the drawings.
1 and 2 show two examples of the film for protecting a chip of the present invention having a curable protective film-forming layer on a release sheet. FIG. 1 shows both sides of the curable protective film-forming layer 2. FIG. 2 shows a configuration in which the release sheet 1 is temporarily attached to one side of the curable protective film forming layer 2.
Below, the structure of a peeling sheet and a curable protective film formation layer is demonstrated in order. Moreover, the manufacturing method and usage method of this chip protection film will also be described.

<Peeling sheet>
The release sheet is used for the purpose of improving the handleability of the chip protection film and for the purpose of protecting the curable protective film forming layer.
The surface tension of the release sheet is preferably 40 mN / m or less, and particularly preferably 35 mN / m or less. Such a release sheet having a low surface tension can be obtained by appropriately selecting the material, and can also be obtained by applying a silicone resin or the like to the surface of the sheet and performing a release treatment.
The thickness of the release sheet is usually about 5 to 300 μm, preferably about 10 to 200 μm, and particularly preferably about 20 to 150 μm.

  Examples of release sheet materials include polyethylene film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, polyphenyl chloride film, vinyl chloride copolymer film, polyethylene terephthalate film, polyethylene naphthalate film, and 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 A fluororesin film or the like is used. These crosslinked films are also used. Furthermore, these laminated films may be used.

<Curable protective film forming layer>
The curable protective film-forming layer is the most characteristic layer of the present invention, and uses (A) a polyamide-based block copolymer and (B) an epoxy resin as polymer components, and (C) silica, (D ) Dyes and / or pigments are essential components.
In addition to the components (A) to (D), this layer can contain (E) a curing agent for epoxy resin, (F) a coupling agent, and (G) other components. These components will be described in order below.

(A) Polyamide-based block copolymer The polyamide-based block copolymer used in the present invention comprises a phenolic hydroxyl group-containing aromatic polyamide oligomer having aminoaryl groups at both terminal groups, and a polybutadiene having carboxyl groups at both terminals. / Can be formed by reacting with acrylonitrile copolymer. As this block copolymer, for example, those described in JP-A-6-299133 can be used.
In the present invention, the weight ratio of polybutene / acrylonitrile copolymer to phenolic hydroxyl group-containing aromatic oligomer is preferably 2/8 to 8/2, more preferably 4/6 to 6/4.
By using this polyamide block copolymer, it is possible to suppress warping of the wafer after the chip protection film is cured. The content of the phenol component having a phenolic hydroxyl group in the polyamide-based block copolymer (A) is preferably 1000 to 10000 g / eq, more preferably 3000 to 6000 g / eq, as a phenol equivalent.

  The phenolic hydroxyl group-containing aromatic polyamide oligomer having aminoaryl groups at both ends is synthesized by condensation polymerization of an aromatic diamine component and an aromatic dicarboxylic acid component. A phenolic hydroxyl group-containing aromatic polyamide oligomer can be produced by mixing an aromatic diamine having a hydroxyl group or an aromatic dicarboxylic acid having a hydroxyl group into the aromatic diamine component or aromatic dicarboxylic acid component. In addition, the formation of aminoaryl groups at both terminal groups of the oligomer can be easily achieved by subjecting the aromatic diamine component to a polycondensation reaction in an excess amount relative to the aromatic dicarboxylic acid component.

Examples of the aromatic diamine component include m-phenylenediamine, p-phenylenediamine, m-tolylenediamine, 4,4′-diaminodiphenyl ether, 3,3′-dimethyl-4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl thioether, 3,3′-dimethyl-4,4′-diaminodiphenyl thioether, 3,3′-diethoxy-4,4′-diaminodiphenyl thioether, 3 , 3′-diaminodiphenylthioether, 4,4′-diaminobenzophenone, 3,3′-dimethyl-4,4′-diaminobenzophenone, 3,3′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, 3,3 '-Dimethoxy-4,4'-diaminodiphenylthioether, 2,2' Bis (3-aminophenyl) propane, 2,2′-bis (4-aminophenyl) propane, 4,4′-diaminodiphenyl sulfoxide, 4,4′-diaminodiphenylsulfone, benzidine, 3,3 ′ -Dimethylbenzidine, 3,3'-dimethoxybenzidine, 3,3'-diaminobiphenyl, p-xylylenediamine, m-xylylenediamine, o-xylylenediamine, 2,2'-bis (3-amino Phenoxyphenyl) propane, 2,2′-bis (4-aminophenoxyphenyl) propane, 1,3-bis (4-aminophenoxyphenyl) benzene, 1,3′-bis (3-aminophenoxyph) propane, 4 , 4 ′-(p-phenylenediisopropylidene) bisaniline and the like.
However, it is not limited only to these. Moreover, you may use these 1 type or in mixture of 2 or more types.

Examples of the dicarboxylic acid component include phthalic acid, isophthalic acid, terephthalic acid, 4,4′-oxydibenzoic acid, 4,4′-biphenyldicarboxylic acid, 3,3′-, methylene dibenzoic acid, 4 , 4′-methylene dibenzoic acid, 4,4′-thiodibenzoic acid, 3,3′-carbonyl dibenzoic acid, 4,4′-carbonyl dibenzoic acid, 4,4′-sulfonyldibenzoic acid, 1 , 5-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,2-naphthalenedicarboxylic acid, and the like.
However, it is not limited only to these. Moreover, you may use these 1 type or in mixture of 2 or more types.

Examples of the aromatic diamine having a hydroxyl group include 3,3′-dihydroxy-4,4′-dianiline, 2,2-bis (3′-amino-4-hydroxyphenyl) propane, and 2,4-dihydroxy. Examples include -1,5-diaminobenzene and 5-hydroxy-1,3-diaminobenzene.
Examples of the aromatic dicarboxylic acid having a hydroxyl group include 5-hydroxyisophthalic acid, 4-hydroxyisophthalic acid, 2-hydroxyisophthalic acid, 3-hydroxyisophthalic acid, and 2-hydroxyterephthalic acid.
However, it is not limited to aromatic diamines having these hydroxyl groups or aromatic dicarboxylic acids having hydroxyl groups.

Polyamide used in the present invention by polycondensing a phenolic hydroxyl group-containing aromatic polyamide oligomer having aminoaryl groups at both ends and a polybutadiene / acrylonitrile copolymer having carboxyl groups at both ends thus synthesized. A system block copolymer can be synthesized.
As the polybutadiene / acrylonitrile copolymer, those synthesized by a known method for introducing carboxyl groups at both ends can be used. As the average degree of polymerization of each component, those having an average degree of polymerization (x, y) in formula 1 described later can be used.

  Said polycondensation can be performed by the conventionally well-known method. For example, direct dehydration polycondensation between carboxyl group and amino group, polymerization method in which carboxyl group is converted to acid chloride with thionyl chloride and then reacted with amine, synthesis using polycondensation catalyst with phosphite and pyridine A method or the like is preferably used.

  The polyamide block copolymer formed by such condensation polymerization is represented by the following formula 1, for example. In consideration of physical properties such as tensile strength and tensile modulus of the polyamide block copolymer, in formula 1, the average degree of polymerization x, y, z, l, m and n is x = 3 to 7, y = 1 to 1. 4, z = 5 to 15, l + m = 2 to 200, and preferably m / (m + l) ≧ 0.04. l and n represent an integer of 1 or more.

(B) Epoxy resin Epoxy resin is for forming a protective film excellent in heat resistance, mounting reliability, etc. by curing, and is not particularly limited as long as it exhibits an adhesive action by curing. It should be bifunctional or higher, preferably having a weight average molecular weight of less than 5,000, more preferably less than 3,000. The molecular weight is preferably 300 or more, more preferably 500 or more. The epoxy equivalent is usually 50 to 5,000 g / eq.

Examples of such epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, alicyclic epoxy resins, aliphatic chain epoxy resins, phenol novolac type epoxy resins, and cresol novolac types. Epoxy resin, bisphenol A novolak type epoxy resin, diglycidyl etherified product of biphenol, diglycidyl etherified product of naphthalenediol, diglycidyl etherified product of phenol, diglycidyl etherified product of alcohol, alkyl substitution products thereof, Bifunctional epoxy resins such as halides and hydrogenated products, and novolac type epoxy resins can be mentioned. Moreover, what is generally known, such as a polyfunctional epoxy resin and a heterocyclic ring-containing epoxy resin, can also be applied.
These may be used alone or in combination of two or more. In addition, components other than the epoxy resin may be contained as impurities within a range that does not impair the characteristics.

  In such an epoxy resin, the ratio of the content of the (A) polyamide block copolymer and the content of the (B) epoxy resin is (A) / (B) = 0.2 to 2 in mass ratio. It is preferable to use it in a ratio that is in the range of 0.0, and it is preferable to use it in a ratio that is in the range of 0.3 to 1.0. When the above ratio is less than 0.2, it is difficult to suppress warping after curing, and problems are likely to occur due to the flexibility of the film. Moreover, when said ratio exceeds 2.0, it will be easily a problem in terms of sticking property and adhesion reliability.

(C) Silica Silica has a function of bringing the thermal expansion coefficient of the cured protective film closer to the thermal linear expansion coefficient of the wafer, thereby reducing the warpage of the wafer. Moreover, the recognizability of laser marking can be improved by using silica.
Examples of such silica include, but are not limited to, crystalline silica and synthetic silica. Among these, synthetic silica is preferable, and synthetic silica of the type in which α-ray sources that cause malfunction of the semiconductor device are removed as much as possible is most suitable.
The particle size of silica is preferably 0.1 to 5 μm, more preferably 0.5 to 3 μm. If the thickness is less than 0.1 μm, the silica is likely to be aggregated and the recognizability of the laser marking is difficult to obtain. If it exceeds 5 μm, it tends to be a foreign matter on the film.

  As for silica, the ratio of the total content of (A) polyamide block copolymer and (B) epoxy resin, which is a polymer component, and the content of (C) silica is a mass ratio [(A) + (B) ] / (C) = 0.15 to 1.0 is preferably used, more preferably 0.20 to 0.8, and still more preferably 0.3 to 0.6. Use in proportions. If the above ratio is less than 0.15, problems are likely to occur in terms of adhesion to a wafer and adhesion reliability. Moreover, when said ratio exceeds 1.0, the curvature of the wafer after hardening cannot be reduced or it becomes difficult to obtain the recognizability of laser marking.

(D) Dye and / or Pigment Dye and pigment are added mainly to improve the recognizability of the laser marking formed on the cured film (protective film). Examples of such pigments include carbon black and various inorganic pigments. Also, various organic pigments such as azo, indanthrene, indophenol, phthalocyanine, indigoid, nitroso, xanthene, oxyketone and the like can be mentioned.
The amount of addition varies depending on the type, but generally it is 0.1 to 10% by weight, preferably about 0.3 to 5% by weight, based on all components forming the protective film forming layer.

(E) Curing agent As the curing agent for the epoxy resin, for example, a phenolic resin can be used. As the phenolic resin, a condensate of phenols such as alkylphenol, polyhydric phenol, naphthol and aldehydes is used without particular limitation. The phenolic hydroxyl group contained in these phenolic resins can easily undergo an addition reaction with the epoxy group of the epoxy resin by heating to form a cured product having high impact resistance.
The phenolic resin includes phenol novolak resin, o-cresol novolak resin, p-cresol novolak resin, t-butylphenol novolak resin, dicyclopentadiene cresol resin, polyparavinylphenol resin, bisphenol A type novolak resin, or a modification thereof. A thing etc. are used preferably.

In addition, a thermally activated latent epoxy resin curing agent can be used in combination as a curing agent. This curing agent is a type of curing agent that does not react with epoxy resin at room temperature and is activated by heating above a certain temperature, and reacts with epoxy resin. As an activation method, active species (anions, Cations), a method in which the resin is stably dispersed in the epoxy resin at around room temperature and is dissolved and dissolved in the epoxy resin at a high temperature to start the curing reaction, and is eluted at a high temperature with a molecular sieve encapsulated type curing agent. There are a method for initiating a curing reaction, a method using a microcapsule, and the like.

Examples of the thermally active latent epoxy resin curing agent include various onium salts, high melting point active hydrogen compounds such as dibasic acid dihydrazide compounds, dicyandiamide, amine adduct curing agents, and imidazole compounds.
As the imidazoles, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate and the like are preferably used. Alternatively, two or more kinds can be used in combination. Imidazoles are commercially available, for example, from Shikoku Kasei Kogyo Co., Ltd. under the trade names 2E4MZ, 2PZ-CN, and 2PZ-CNS.

(F) Coupling agent A coupling agent may be added to the curable protective film-forming layer for the purpose of improving the adhesion and adhesion between the curable protective film-forming layer and the adherend. The coupling agent can improve the adhesion and adhesion to the adherend without impairing the heat resistance of the cured coating, and also improve the water resistance (moisture heat resistance). The coupling agent is preferably a silane (silane coupling agent) because of its versatility and cost merit.

(G) Other components As other components, a crosslinking agent such as an organic polyvalent isocyanate compound, an organic polyvalent imine compound, and an organometallic chelate compound can be added in order to adjust the cohesive force before curing. Further, for example, a butadiene rubber, a silicone rubber, an antistatic agent or the like can be contained as a flame retardant and a stress relaxation agent.

<Manufacturing method>
The film for chip protection of the present invention is generally known as a roll knife coater, a gravure coater, a die coater, a reverse coater, or the like, containing a composition comprising each component constituting the curable protective film forming layer on the release surface of a release sheet. According to the method of (1), it can be applied directly or by transfer and dried. In addition, said composition can be apply | coated after making it melt | dissolve or disperse | distribute to a solvent as needed.
The thickness of the curable protective film forming layer is usually 3 to 300 μm, preferably 10 to 60 μm. If the curable protective film-forming layer is too thin, it is difficult to obtain protection and reinforcement effects, and problems such as color unevenness tend to occur. Moreover, when the curable protective film forming layer becomes too thick, it becomes difficult to cure the entire film by heating.

<How to use>
The use application of the film for chip protection of the present invention is not particularly limited as long as it is a chip protection application.
In this case, first, the chip protection film is heated to 40 ° C. or higher on the back surface of the wafer and laminated by applying a pressure of 0.05 to 0.5 MPa, and the film is cut into a wafer size. The film laminated on the wafer is heated at 100 to 200 ° C. for about 0.5 to 3 hours to cure the film and protect the entire wafer surface. The obtained wafer with a film can be separated into pieces by dicing and used as a chip protected with a protective film.

  Next, the present invention will be described in more detail based on examples, but the present invention is not limited to the following examples.

Examples 1-4 and Comparative Examples 1-3
A coating solution for a curable protective film forming layer was prepared by blending the components shown in Table 1 (Examples 1 to 4) and Table 2 (Comparative Examples 1 to 3).
In addition, as for the unit of the numerical value in Table 1 and Table 2, all are a mass part. Moreover, the code | symbol of each component in Table 1 and Table 2 is as follows.

A ′: Acrylic polymer (acrylic copolymer having a weight average molecular weight of 800,000 and a glass transition temperature of −10 ° C.)
A: polyamide block copolymer (weight ratio of A ₂ with respect to the copolymer (A ₁ formed from a phenolic hydroxyl group-containing aromatic polyamide oligomer A ₁ and polybutadiene / acrylonitrile copolymer A ₂ Metropolitan 5/5) (A) Content of phenol component in component is 4000 / eq in phenol equivalent)
B1: Epoxy resin (1) (liquid bisphenol A type epoxy resin having an epoxy equivalent of 180 to 200)
B2: Epoxy resin (2) (o-cresol novolac type epoxy resin having an epoxy equivalent of 210 to 230)
C1: Silica (1) (Fused silica crushing type with an average particle size of 8 μm)
C2: Silica (2) (Synthetic silica having an average particle size of 1.2 μm)
D: Dye and pigment [Black pigment (azo type)]
E1: Curing agent (1) [phenol resin (triphenylmethane novolak)]
E2: Curing agent (2) [imidazole compound (2-phenyl 4,5-dihydroxymethylimidazole)]

Next, after coating and drying each of the above coating solutions on a release sheet made of a polyethylene terephthalate (PET) film having a thickness of 38 μm at 130 ° C. for 3 minutes so that the dry film thickness becomes 30 μm, Another release sheet similar to the above was laminated thereon to produce a chip protective film having a three-layer structure comprising release sheet / curable protective film forming layer / release sheet.
About this chip protection film, film sticking property, laser mark recognizability, wafer warpage and mounting reliability were examined by the following methods. These results were as shown in Table 3.

<Film pasting property>
The curable protective film forming layer was bonded to a silicon wafer (# 2000 ground, 350 μm thickness, 8 inches) by heating (80 ° C.).
Thereafter, it was confirmed whether or not the curable protective film forming layer was transferred to the wafer when the release sheet was peeled off. Those that could be transferred were marked with ◯, and those that could not be transferred were marked with X.

<Laser mark recognition>
The curable protective film forming layer was bonded to a silicon wafer (# 2000 ground, 350 μm thickness, 8 inches) by heating (80 ° C.), and the release sheet was removed. Then, it processed at 150 degreeC for 1 hour with the heating furnace, and hardened | cured the protective film formation layer.
Laser marking was performed on the obtained protective film layer (manufactured by Keyence: using ML-G9320, character height 0.75 mm, character width 0.5 mm), and the recognition of printing was observed with a microscope. Recognition evaluation was performed using a CCD camera mounted on a microscope. A contrast value measured by a CCD camera was 85% or more, ◎, less than 85%, 70% or more, ◯, less than 70%, 30% or more, Δ, and less than 30%, ×.

<Wafer warpage>
An 8-inch silicon wafer was made to be # 2000-100 μm thick using a grinding apparatus (Disco-made: DFG-840). After the chip protective film was bonded to the ground wafer back surface by heating (80 ° C.), the film was cut into a wafer shape. The release sheet was removed, and the protective film forming layer was cured by treatment at 150 ° C. for 1 hour in a heating furnace.
The obtained wafer with the protective film layer was allowed to stand on a smooth glass plate, and the height of the center and the edge of the wafer was measured, and the difference was taken as the amount of warpage.

<Mounting reliability>
Heated (80 ° C) bonding to the back of a silicon wafer (# 2000 ground, 350μm thickness, 8 inches) ground with a curable protective film forming layer, and cured in a heating furnace at 150 ° C for 1 hour to cure the protective film forming layer I let you. A dicing tape was bonded to the protective film side of the obtained wafer with a protective film layer, and the wafer was diced to 5 mm × 5 mm.
Each divided silicon chip was treated in a constant temperature and humidity chamber of 85 ° C. and 85% RH for 168 hours, and then heated in an IR reflow furnace at 250 ° C. for 120 seconds.
Thereafter, the presence or absence of peeling between the obtained silicon chip and the protective film layer was observed with SAT (ultrasonic imaging device: manufactured by Hitachi Construction Machinery Finetech Co., Ltd.). Of the 20 samples, those in which peeling occurred were counted.

  From the above results, a polyamide block copolymer and an epoxy resin are used in combination with the polymer component of the curable protective film forming layer, and silica and a dye or pigment are contained as essential components. By setting the ratio to the content of the resin within a specific range (Examples 1 to 4), in particular, the ratio of the content of the polyamide block copolymer and the content of the epoxy resin in the polymer component was set to the specific range. Thus (Examples 3 and 4), it can be seen that a film for chip protection that is excellent in film sticking property, can suppress warping of the wafer, and is excellent in mounting reliability and laser mark recognizability can be provided.

  In contrast, in Comparative Example 1 in which an acrylic polymer is used instead of the polyamide block copolymer, the warpage of the wafer cannot be suppressed, and the recognizability of the laser mark also decreases. Further, in Comparative Examples 2 and 3 in which the ratio of the content of the polymer component and the content of silica deviates from a specific range, the warpage of the wafer cannot be suppressed, and the mounting reliability and the laser mark recognition are poor (Comparative Example). 2) Affixing to a wafer becomes difficult (Comparative Example 3).

It is sectional drawing which shows an example of the film for chip | tip protection of this invention. It is sectional drawing which shows the other example of the film for chip protection of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Release sheet 2 Curable protective film formation layer

Claims (4)

A film for chip protection used in the manufacture of a semiconductor chip mounted in a face-down manner, wherein the film for chip protection has a curable protective film forming layer, and the curable protective film formed layer is used as a circuit of a wafer. adhered to the back surface of the forming surface, in the chip protection film used to chip the wafer with the protective film by dicing the wafer with a protective film after curing, (a) a phenolic hydroxyl group-containing polyamide-based block copolymer formed from an aromatic polyamide oligomer and polybutadiene / acrylonitrile copolymer, and also contains as the epoxy resin (B), (C) silica, (D) an essential component dyes and / or pigments The ratio of the content of (A) + (B) and the content of (C) is [(A) + (B)] / (C) = 0.15 to 1.0 in terms of mass ratio. Chip protection film characterized by having a cured protective film forming layer is in the range.
  The ratio of the content of (A) and the content of (B) is in the range of (A) / (B) = 0.2 to 2.0 in terms of mass ratio. Chip protection film.   (C) The chip protective film according to claim 1 or 2, wherein the average particle diameter of silica is in the range of 0.1 to 5 µm.   The film for chip protection according to claim 1, further comprising a curable protective film forming layer on the release sheet.

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