TW201430930A - Method for manufacturing semiconductor chips and surface protective tape for thin-film grinding used in same - Google Patents

Abstract

To provide a high precision and simple method for manufacturing semiconductor chips in semiconductor chip manufacturing that carries out back surface grinding of a semiconductor wafer which is used in a flip chip mounting process and has bump electrodes and simultaneously or in a process thereafter carries out chip formation without using underfilling, and also to provide a surface protective tape for thin-film grinding used in that method. This manufacturing method for semiconductor chips grinds the back surface of a semiconductor wafer after formation of a modified layer within a wafer with bump electrodes, which has bumps for electrodes, on the semiconductor wafer on which a semiconductor circuit has been formed, and carries out division into individual chips in a batch. This method for manufacturing semiconductor chips has a step for applying surface protective tape for thin-film grinding in which a bonding film is laminated on an adhesive layer in an adhesive tape that has an adhesive layer on a base material film to the side of a semiconductor wafer on which a semiconductor circuit is formed on the bonding film side after formation of the modified layer and before the back surface of the semiconductor wafer is ground, and a step for creating a state in which only the bonding film bonds to the chips when the chips are picked up after back surface grinding of the semiconductor wafer or when transferred to a tape used for pick-up. The surface protective tape for thin-film grinding used therein is also provided.

Description

Method for manufacturing semiconductor wafer and surface protection tape for film polishing used in the method

The present invention relates to a method of manufacturing a semiconductor wafer and a surface protection tape for film polishing used in the method.

In recent years, the popularity of IC cards or the rapid increase in capacity of USB memory has continued to increase, and further thinning is expected as the number of overlapping chips increases. Therefore, it is necessary to thin a semiconductor wafer having a thickness of about 200 μm to 350 μm to a thickness of 50 to 100 μm or less. As a method for achieving the thinning of such a wafer, there is known a method of performing a thin film polishing using a special tape in a usual step, or a manufacturing method called a first cutting, that is, forming a side surface from the wafer. A method of manufacturing a semiconductor wafer that is polished from the back side after a groove having a predetermined depth. In this method, a thin wafer can be efficiently produced by simultaneously performing back surface polishing of the wafer and dividing into wafers. Further, by reducing the polishing stress on the wafer and improving the bending strength of the wafer, the application to a device which is especially polished to a film of 100 μm or less is investigated.

The trend of thinning and large-diameter semiconductor wafers, especially in the field of NAND type or NOR type flash memory, or DRAM as volatile memory, etc. tendency. Now, grinding a 12-inch wafer to a thickness of 100 μm or less is becoming standard.

Memory system components are required to improve performance by overlapping wafers Grinding. Therefore, by using a method which is specified in the manufacture of a thin film wafer, that is, a manufacturing method called a step of the first cutting method (refer to Patent Document 1, Patent Document 2) or an adhesive sheet for the manufacturing step thereof (refer to the patent) Document 3) is a special adhesive sheet for film polishing (see Patent Document 4), a diced or bonded wafer (see Patent Document 5), or an adhesive layer made of a specific resin. According to the tape (refer to Patent Document 6), it is possible to manufacture a flash memory or the like which is low in cost and high in performance.

On the other hand, in recent years, with the spread of smart phones or the performance of mobile phones and the miniaturization and performance improvement of music players, there are electrodes attached to the use of impact resistance. Wafers used in flip chip mounting of wafers also increase the requirements for thin film formation. Further, it is necessary to perform film polishing of 100 μm or less for the wafer with bumps. The bump for the flip chip connection is increased in density in order to increase the transfer speed, and the height of the bump is lowered. In this case, the distance between the bumps is shortened. Further, in recent years, the DRAM has been subjected to flip chip connection, thereby accelerating the thinning of the wafer.

The flip-chip mounting system has been attracting attention as a method of miniaturizing and increasing the density of electronic devices in recent years, and it is possible to assemble a semiconductor element with a minimum area. A bump is formed on the electrode of the semiconductor device used in the flip chip, and the bump is electrically bonded to the wiring on the circuit board. As a component of the bumps, solder or gold is mainly used. The solder bump or gold bump is formed by vapor deposition or plating on an exposed aluminum terminal connected to the internal wiring of the wafer.

The wafer with the bumps is difficult to perform film processing because of the large unevenness on the surface thereof, and if the back surface is polished by a normal tape, the wafer is broken or the thickness precision of the wafer is deteriorated. Therefore, in the polishing of the bump-attached wafer, a specially designed surface protection tape is used for processing (refer to Patent Document 7).

However, these belts sufficiently absorb the bumps to ensure the abrasiveness, so that it is very difficult to achieve at the same time as the peelability. The final thickness of the wafer-coated wafer to date has a certain thickness of 200 μm or more, which ensures rigidity and is barely peelable. However, the recent wafer final Since the thickness becomes a film and the bump density also becomes high, there arises a problem that the tape cannot be easily peeled off. Moreover, when the peeling property is ensured, the adhesion is insufficient, and the polishing water is infiltrated or the paste remains during the back surface polishing. Further, since the adhesive is adhered to the front surface of the wafer, contamination of the organic material is likely to occur, and the adhesion of the underfill is also deteriorated, so that the yield is not improved when the package is performed.

On the other hand, if the semiconductor device connected by flip chip is directly used for packaging, the electrode of the connection portion is exposed to the air, and the difference in thermal expansion coefficient between the wafer and the substrate is large, so that the thermal history of subsequent steps such as reflow is made. The stress applied to the connecting portion of the bump is large, so that there is a problem in the mounting reliability.

In order to solve the above problems, after the bumps and the substrate are connected, in order to improve the reliability of the joint portion, the gap between the semiconductor element and the substrate is filled with a resin such as a primer or NCP (Non Conductive Paste) and hardened. , fixing the semiconductor component and the substrate.

However, the number of electrodes of a semiconductor element such as a flip chip is usually large, and the electrode is disposed around the semiconductor element in terms of circuit design. Therefore, when the resin slurry as the primer is filled, when the liquid resin flows from the electrodes of the semiconductor elements by capillary action, the resin is not sufficiently spread and the unfilled portion is easily formed, and the operation of the semiconductor element is not performed. It is stable, etc., and therefore has a problem of poor operation or low humidity resistance. Further, when the wafer size is small, the liquid crystal resin bleeds to contaminate the substrate, or if the distance between the electrodes is narrowed, it is difficult to flow into the resin. Moreover, it takes too much time to fill the resin by the flip chip-connected semiconductor elements one by one, and there is a problem in productivity. On the other hand, in the method of monolithizing a wafer wafer after the thermal bonding of a film-form adhesive (NCF: Non Conductive Film), it is advantageous to simplify the step compared with the resin paste. However, as the thickness of the wafer is reduced, wafer damage is likely to occur during thermocompression bonding. Therefore, it is necessary to polish the back surface of the wafer after heat-bonding a film-like adhesive (NCF) to a thick wafer. Therefore, the number of steps increases and is not efficient.

In contrast, in the previous adhesive tape for backside polishing (adhesive on the substrate film) In the combination of the adhesive layer and the adhesive film (adhesive layer), the adhesive layer and the adhesive layer (adhesive tape and the adhesive film) have high affinity for peeling off the adhesion from the wafer after the wafer is back-grinded. The peeling ability of the tape (adhesive layer) is liable to rise, and there is a problem that wafer damage in the peeling step is liable to occur. In addition, in order to improve the embedding property of the adhesive film on the uneven substrate and improve the subsequent reliability, it is necessary to reduce the melt viscosity at the time of heat bonding, but it is difficult to increase the peeling ability of the self-adhesive tape by heat bonding. The problem of peeling off the adhesive tape after self-heating bonding.

In addition, the research on the above-mentioned problems has been carried out (see Patent Documents 8 and 9). However, in recent years, thin film formation and large diameter reduction have caused defects such as cracks in the conventional semiconductor wafer manufacturing method. In the case of wafer rupture, the problem of poor yield is generated. In particular, in the case of polishing in which the wafer thickness is 100 μm or less, the deterioration of the yield is particularly severe, and it is difficult to manufacture stably. Further, it is difficult to increase the bending strength in the conventional back surface polishing and wafer dicing by dicing, and many cases cause defects in packaging.

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2008-251934

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2009-27054

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2004-331743

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2000-150432

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2007-227575

[Patent Document 6] Japanese Patent Laid-Open No. 10-8001

[Patent Document 7] Japanese Patent Laid-Open Publication No. 2004-235395

[Patent Document 8] Japanese Patent Laid-Open Publication No. 2006-49482

[Patent Document 9] Japanese Patent Laid-Open Publication No. 2002-118147

Therefore, an object of the present invention is to provide a semiconductor for performing back surface polishing of a semiconductor wafer having a bump electrode for use in a flip chip mounting step, or for performing wafer formation (singulation) in a subsequent step. In the manufacture of wafers, a method of manufacturing a semiconductor wafer with high precision and simplicity without using a primer or NCP or NCF.

Further, another object of the present invention is to provide a surface protection tape for film polishing which is used in the above method.

The inventors of the present invention conducted various studies to overcome the problems in the flip chip mounting step, and as a result, found that the wafer circuit board with bumps having a height of 100 μm or less is ground to a thickness of 200 μm or less, in particular, A wafer circuit substrate having bumps having a height of 50 μm or less is polished into a film having a thickness of 100 μm or less, and during the wafer formation, a modified layer is formed in advance in the wafer with the bumps (corresponding to wafers to be wafers) a layer of a modified portion that is disposed at a position separated by a predetermined depth from the front side of the wafer, the strength of the modified portion being lower than that of the unmodified wafer around the wafer, and the subsequent laminated layer Then, the surface protective tape of the film and the adhesive tape is subjected to back surface polishing of the wafer, thereby performing thinning and wafer formation at one time, and bonding or picking up the pick-up tape for transfer, and only following The film is then transferred or picked up on the wafer, whereby the flip chip structure can be easily performed, and the improvement in the reliability of the structure and the shortening of the steps can be achieved as compared with the previous steps, based on which the present invention is formed.

That is, according to the present invention, the following means are provided.

(1) A method of manufacturing a semiconductor wafer, after forming a modified layer in a bump-attached semiconductor wafer having a semiconductor circuit and having bumps as electrodes, grinding the back surface of the semiconductor wafer, and dividing the semiconductor wafer into one The wafer has the following steps: after forming the modified layer and before polishing the back surface of the semiconductor wafer, the adhesive layer of the adhesive tape having the adhesive layer on the base film is laminated with the adhesive film. a surface protection tape for film polishing, which is attached to a side of a semiconductor wafer on which a semiconductor circuit is formed with the above-mentioned adhesive film side; and when picking up after polishing the back surface of the semiconductor wafer, or when transferring to a pick-up In the case of the tape, it is assumed that only the bonding film is in the state of the wafer.

(2) The method of manufacturing a semiconductor wafer according to (1), wherein the step of merely attaching the bonding film to the state of the wafer is performed directly from the surface protection tape without using a transfer film (pickup tape) The step of picking up.

(3) The method for producing a semiconductor wafer according to (1) or (2), comprising the step of simultaneously dividing the adhesive film and the wafer by extending the surface protective tape for film polishing.

(4) The method for producing a semiconductor wafer according to (1) or (2), wherein after the wafer is once cut by back surface polishing of the semiconductor wafer, only the surface protective tape for polishing the film is irradiated by laser The above-mentioned adhesive film is divided.

(5) A surface protective tape for film polishing, which is formed by laminating a film on an adhesive layer having an adhesive layer of an adhesive layer on a base film, wherein the elastic modulus of the adhesive film at 250 ° C is 10 MPa or less, the saturated moisture absorption rate is 1.5% by volume or less, and is composed of a single or plural layer containing at least one selected from the group consisting of a (meth)acrylic copolymer and a phenoxy resin as a binder.

(6) The surface protection tape for film polishing according to (5), wherein the pressure-sensitive adhesive layer is an ultraviolet curing type.

(7) The surface protective tape for film polishing according to (5) or (6), wherein the adhesive layer is a (meth)acrylic copolymer as a main component, and the gel fraction is 80% or more.

(8) The surface protection tape for film polishing according to any one of (5) to (7) wherein the adhesive film has a surface free energy of 25 to 45 mN/m and a saturated moisture absorption rate of 1.5% by volume or less.

(9) The surface protection tape for film polishing according to any one of (5) to (8) wherein the above-mentioned adhesive film contains an epoxy resin selected from the group consisting of epoxy propylene ether epoxy resin and epoxy resin. At least one resin selected from the group consisting of propylamine epoxy resin, propylene acrylate epoxy resin, and alicyclic epoxy resin.

(10) The surface protection tape for film polishing according to any one of (5) to (9) wherein the adhesive film contains a bisphenol resin.

(11) The surface protective tape for film polishing according to (10), wherein the bisphenol-based resin is at least one selected from the group consisting of bisphenol F diglycidyl ether resin and bisphenol A diglycidyl ether resin. 1 species.

(12) The surface protective tape for film polishing according to any one of (5), wherein the adhesive film contains an inorganic filler in an amount of less than 60 parts by mass based on 100 parts by mass of the resin component in the adhesive film. Parts by mass.

(13) The surface protection tape for film polishing according to any one of (5) to (12) wherein the above-mentioned adhesive film contains a compound having a functional group crosslinked with an isocyanate curing agent or an epoxy curing agent. And shows flux activity.

In the present invention, the modified layer refers to a layer which is provided corresponding to a position to be divided at the time of wafer formation and which includes a modified portion having a predetermined depth on the front surface of the wafer, and the strength of the modified portion is lower than that of the surrounding portion. Modified wafers.

In addition, the "adhesive" is a specific adhesive agent with respect to the "adhesive agent", and means an agent which can be peeled off by a treatment such as hardening after adhesion. For example, the term "radiation hardening type adhesive" means an adhesive which can be cured and peeled off by applying radiation such as ultraviolet rays after application to a wafer or the like.

According to the present invention, after the modified layer is formed in the semiconductor wafer, the step of thinning is performed by a backgrinding step, or in the subsequent step, the step of fabricating the semiconductor wafer for wafer division is performed, and A high precision and simple manufacturing method is provided.

Moreover, according to the present invention, there is provided a surface protection tape for film polishing which is preferably used in the above semiconductor wafer manufacturing method.

The above and other features and advantages of the present invention will become more apparent from the description of the appended claims.

1‧‧‧ wafer

1A‧‧‧ wafer front

1B‧‧‧ wafer back

2‧‧‧Modified layer

2A‧‧‧Transformation Department

3‧‧‧Adhesive tape

4‧‧‧Base film

5‧‧‧Adhesive layer

6‧‧‧Binder layer (following film)

6A‧‧‧Separated adhesive layer (following film)

9‧‧‧When the wafer in the back grinding

10‧‧‧A wafer with a back-grinded state

10A‧‧‧Segmented wafers

11‧‧‧ Picking belt

11A‧‧‧Extended Pickup Tape

12‧‧‧ ring frame

17‧‧‧Single wafer with adhesive

21‧‧‧Fixed belt

21A‧‧‧Fixed straps

22‧‧‧ ring frame

27‧‧‧Single wafer with adhesive

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing the first half of the process of a preferred embodiment of the method for fabricating a semiconductor wafer of the present invention.

Fig. 2 is a schematic view showing an example of the case where the film is transferred to the pickup tape in the second half of the process of the above preferred embodiment of the method for manufacturing a semiconductor wafer of the present invention.

Fig. 3 is a schematic view showing an example of the case where the film is not transferred in the second half of the process of the above preferred embodiment of the method for manufacturing a semiconductor wafer of the present invention.

<<Surface protection tape for film polishing>>

The surface protective tape for film polishing of the present invention (hereinafter also referred to simply as "surface protective tape") is obtained by laminating a film (adhesive layer) on an adhesive layer of an adhesive tape having an adhesive layer on a base film. And by an adhesive tape for the purpose of protecting the front side of the wafer (the circuit) and an adhesive film for the purpose of bonding the wafer.

<Substrate film>

The thickness of the base film is not particularly specified, and is preferably from 10 to 200 μm in terms of manufacturability. Further, it is more preferably 25 to 150 μm in consideration of warpage at the time of polishing. When the base film is too thin, the rigidity of the belt disappears, so that the deflection is likely to occur, and when it is housed in a casing, an arm contact due to deflection is caused. On the other hand, if the base film is too thick, warping tends to occur due to release of residual stress at the time of film formation.

As the material of the substrate film of the present invention, polyolefins such as polyethylene, polypropylene, and polybutene, ethylene-vinyl acetate copolymer, ethylene-(meth)acrylic copolymer, and ethylene-(A) are preferable. Vinyl copolymer such as acrylate copolymer, soft polyvinyl chloride, Polymer materials such as polyethylene terephthalate, polyethylene naphthalate, semi-rigid polyvinyl chloride, polyester, urethane, polyamide, polyimide, natural rubber, and synthetic rubber. Further, the base film may be used as a single layer film or a multilayer film in which two or more layers are laminated.

Further, the base film is preferably a visible light permeable person, and more preferably a radiation permeable one.

The substrate film can be formed into a rigid substrate film in the case of the step of transferring to the pickup tape for stretching and dividing after the back surface polishing. As the rigid base film, a synthetic resin film is preferably used in terms of water resistance, heat resistance, rigidity, and the like. As such a rigid substrate, specifically, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyamine, polyacetal, polycarbonate are used. , modified polyphenylene ether, polyphenylene sulfide, polyfluorene, wholly aromatic polyester, polyether ketone, polyimide, or biaxially stretched polypropylene. The rigid substrate film may be a single layer of the above various films or may be a laminate. In the above, as the rigid substrate, it is preferable that the wafer does not cause ionic contamination or the like, and specifically, polyethylene terephthalate, polyethylene naphthalate, and poly pair are particularly preferable. Butylene phthalate, biaxially oriented polypropylene, polyimine, and polyamine. By using a rigid substrate film, it is possible to correct the warpage of the wafer, thereby suppressing warpage.

The thickness of the rigid substrate film is preferably from 25 to 100 μm in terms of the correcting ability and the peeling property of the warpage. If it is too thin, the correcting ability is weak and there is a case where the suppression of warpage is insufficient. If it is too thick, the tape will not be bent when the tape is peeled off, and a load is applied to the wafer, so that the wafer is broken.

The substrate film is preferably selected from polyolefins and polyvinyl chlorides in the case where the step of transferring to the pick-up tape for stretching and dividing after the back surface polishing is not included, and the step of directly performing the stretching and dividing is included. More preferably, it is a polyolefin. The reason for this is that polyvinyl chloride has an influence such as contamination due to bleed of a plasticizer or the like.

In the singulation step using the extended wafer, the stretching is performed by transferring the tensile stress of the surface protection tape for the stretched film polishing to the wafer. Therefore, as a use The following characteristics can be considered for the characteristics of the surface protection tape necessary for the extended wafer division.

1) Even if it is deformed due to extension, it remains rigid

2) Transfer to the wafer without losing the stress imparted during the extension

3) The surface protection tape is not broken when using the extended deformation

Examples of the polyolefin include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate copolymer, and ethylene-(methyl). a homopolymer or copolymer of an ethyl acrylate copolymer, an ethylene-methyl (meth) acrylate copolymer, an ethylene-(meth)acrylic acid copolymer, an ionic polymer, or the like, or a mixture thereof.

In particular, in the case of using a substrate film having an ionic polymer, it is possible to obtain a physical property which is free from a drop point and which is uniform with respect to the unwinding direction and the width direction of the surface protective tape. Therefore, the singulated wafer can be evenly spaced when performing the use of the extended division.

<Adhesive layer>

As the adhesive for the adhesive layer, a (meth)acrylic copolymer is preferred. In the present invention, the adhesive is not limited thereto, and various adhesives can be used to form the adhesive layer. As such an adhesive, for example, a rubber, a polyoxymethylene, a polyvinyl ether or the like can be used as an adhesive for a base polymer.

A crosslinking agent can be blended for the cohesive force of the matrix polymers. Examples of the crosslinking agent include an isocyanate crosslinking agent, an epoxy crosslinking agent, a metal chelate crosslinking agent, an aziridine crosslinking agent, and an amine resin. Further, in the adhesive, various additives may be contained as needed within the range not impairing the object of the present invention.

As the adhesive, a radiation hardening type or a heat foaming type adhesive can be used. As the radiation-curing type adhesive, an adhesive which is cured by ultraviolet rays, electron beams or the like and which is easily peeled off at the time of peeling can be used. As the heat-foaming type adhesive, an adhesive which is easily peeled off by a foaming agent or a swelling agent by heating can be used. As a radiation hardening type adhesive, it is preferably used For example, it is described in Japanese Unexamined Patent Publication No. Hei No. Hei. In the present invention, it is preferred to use an ultraviolet curable adhesive. In this case, as long as it has a property of being cured by radiation and three-dimensionally reticulating, for example, it is used in a blend of a normal rubber-based or (meth)acryl-based pressure-sensitive base resin (polymer). A low molecular weight compound (hereinafter referred to as a photopolymerizable compound) of at least two photopolymerizable carbon-carbon double bonds (ethylenic double bond) and a photopolymerization initiator are used.

The rubber-based or (meth)acrylic base resin is a rubber-based polymer such as natural rubber or various synthetic rubbers, or a polyalkyl (meth)acrylate or an alkyl (meth)acrylate, which is copolymerizable therewith. A (meth)acrylic polymer such as a copolymer of another unsaturated monomer.

Further, by mixing the isocyanate-based curing agent with the above-mentioned adhesive, the initial adhesion can be set to an arbitrary value. As such a hardener, specifically, a polyvalent isocyanate compound such as 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,3-xylene diisocyanate, or 1,4-xylene diisocyanate is used. , diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone II Isocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, isocyanuric acid isocyanate, and the like.

In the case of the ultraviolet curable adhesive, the polymerization hardening time by ultraviolet irradiation and the ultraviolet irradiation amount can be reduced by mixing a photopolymerization initiator into the adhesive. Specific examples of such a photopolymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl diphenyl sulfide, tetramethylthiuram monosulfide, and azobis Nitrile, bibenzyl, diacetyl, β-chloropurine and the like.

The (meth)acrylic polymer is preferably a (meth)acrylic polymer, and preferably contains a (meth)acrylic polymer as a main component.

a (meth)acrylic polymer as a main component (meth)acrylic polymer The component is at least 50% by mass or more, preferably 80% by mass or more (100% by mass or less).

The (meth)acrylic polymer can be cured by radiation irradiation by having at least a side chain having a photopolymerizable carbon-carbon double bond (ethylenic double bond), and further has a functional group such as an epoxy group or a carboxyl group.

The (meth)acrylic polymer having a photopolymerizable carbon-carbon double bond in the side chain may be produced in any manner, and, for example, a (meth)acrylic acid having a functional group (α) in a side chain is preferred. a polymer, a functional group having a photopolymerizable carbon-carbon double bond such as a (meth)acryloyl group and having a functional group (α) reactive with a side chain of the (meth)acrylic polymer (β) The compound obtained by the reaction.

The group having a photopolymerizable carbon-carbon double bond may be any one as long as it has a non-aromatic ethylenic double bond, and is preferably a (meth) acrylonitrile group or a (meth) propylene fluorenyl group ( Methyl) acrylamide, allyl, 1-propenyl, vinyl (including styrene or substituted styrene), more preferably (meth) acrylonitrile or (meth) acryloxy.

Examples of the functional groups (α) and (β) include a carboxyl group, a hydroxyl group, an amine group, a mercapto group, a cyclic acid anhydride group, an epoxy group, and an isocyanate group (-N=C=O).

Here, in the case where one of the functional group (α) and the functional group (β) is a carboxyl group, a hydroxyl group, an amine group, a thiol group, or a cyclic acid anhydride group, the other functional group may, for example, be an epoxy group or an isocyanate group. In the case where the monofunctional group is a cyclic acid anhydride group, the other functional group may, for example, be a carboxyl group, a hydroxyl group, an amine group or a mercapto group. Further, in the case where the monofunctional group is an epoxy group, the other functional group may also be an epoxy group.

The functional group (α) is preferably a carboxyl group or a hydroxyl group, and particularly preferably a hydroxyl group.

The (meth)acrylic polymer having a functional group (α) in the side chain can be obtained by using a (meth)acrylic monomer having a functional group (α), preferably a (meth) acrylate [(especially The alcohol moiety having a functional group (α) is obtained by using a monomer component.

When the (meth)acrylic polymer having a functional group (α) in the side chain is a copolymer Preferably, the copolymerization component is an alkyl (meth)acrylate, and preferably an alkyl (meth)acrylate having a functional group (α) or a group having a photopolymerizable carbon-carbon double bond which is not substituted with an alcohol moiety .

Examples of the (meth) acrylate include methyl acrylate, ethyl acrylate, n-propyl acrylate, n-butyl acrylate, isobutyl acrylate, n-pentyl acrylate, n-hexyl acrylate, n-octyl acrylate, and acrylic acid. Octyl ester, 2-ethylhexyl acrylate, dodecyl acrylate, decyl acrylate, hexyl acrylate, and methacrylate corresponding to the methacrylate.

The (meth) acrylate may be one type or two or more types, and those having a carbon number of 5 or less and a carbon number of 6 to 12 are preferably used.

Further, the more the monomer having a larger carbon number in the alcohol portion, the lower the glass transition point (Tg), and thus the desired glass transition point can be produced. Further, in addition to the glass transition point, it is preferable to blend a low molecular compound having a carbon-carbon double bond such as vinyl acetate, styrene or acrylonitrile for the purpose of improving compatibility and various properties. The content of the monomer component is preferably in the range of 5% by mass or less.

Examples of the (meth)acrylic monomer having a functional group (α) include acrylic acid, methacrylic acid, cinnamic acid, itaconic acid, fumaric acid, phthalic acid, and 2-hydroxyalkyl acrylate. , 2-hydroxyalkyl methacrylates, ethylene glycol monoacrylates, ethylene glycol monomethacrylates, N-methylol acrylamide, N-methylol methacrylamide, Allyl alcohol, N-alkylaminoethyl acrylate, N-alkylaminoethyl methacrylate, acrylamide, methacrylamide, maleic anhydride, itaconic anhydride, Fumar Anhydride, phthalic anhydride, glycidyl acrylate, glycidyl methacrylate, allyl epoxidized ether, a part of an isocyanate group of a polyisocyanate compound having a hydroxyl group or a carboxyl group and a photopolymerizable carbon- A monomer in which a carbon double bond is subjected to amine esterification or the like.

Among these, acrylic acid, methacrylic acid, 2-hydroxyalkyl acrylate, 2-hydroxyalkyl methacrylate, glycidyl acrylate, and glycidyl methacrylate are preferred. Acrylic acid, methacrylic acid, 2-hydroxyalkyl acrylate, methacrylic acid The 2-hydroxyalkyl esters are more preferably 2-hydroxyalkyl acrylates or 2-hydroxyalkyl methacrylates.

The functional group (β) in the compound having a photopolymerizable carbon-carbon double bond and a functional group (β) is preferably an isocyanate group, and examples thereof include an isocyanate (-N=C=O) group. A methyl (meth) acrylate, preferably an alkyl (meth) acrylate substituted with an isocyanate (-N=C=O) group. Examples of such a monomer include 2-isocyanate ethyl methacrylate and 2-isocyanate ethyl acrylate.

In addition, a compound which is preferable in the case where the functional group (β) is an isocyanate group is exemplified as a compound exemplified in the (meth)acrylic monomer having a functional group (α).

The compound having a photopolymerizable carbon-carbon double bond and a functional group (β) is a (meth)acrylic polymer having a functional group (α) with a side chain and a functional group (α) of a side chain of the polymer. Preferably, a hydroxyl group is reacted, and a polymerizable group can be incorporated in the copolymer to lower the adhesion after radiation irradiation.

In the synthesis of the (meth)acrylic copolymer, as the organic solvent in the case of performing the reaction by solution polymerization, a ketone system, an ester system, an alcohol system or an aromatic group can be used, and among them, toluene and ethyl acetate are preferable. A solvent such as ester, isopropanol, benzene, methyl cellulase, ethyl cellosolve, acetone or methyl ethyl ketone which is usually a good solvent for a (meth)acrylic polymer and has a boiling point of 60 to 120 °C. As the polymerization initiator, a radical generator such as an azobis system such as α,α'-azobisisobutyronitrile or an organic peroxide such as benzamidine peroxide is usually used. In this case, if necessary, a catalyst or a polymerization inhibitor can be used in combination, and by adjusting the polymerization temperature and the polymerization time, a (meth)acrylic copolymer having a desired molecular weight can be obtained. Further, as the molecular weight to be adjusted, a solvent such as mercaptan or carbon tetrachloride is preferably used. Further, the reaction is not limited to solution polymerization, and may be other methods such as bulk polymerization or suspension polymerization.

In the above manner, a (meth)acrylic copolymer can be obtained. In the present invention, the molecular weight of the (meth)acrylic copolymer is preferably from about 300,000 to about 1,000,000. If molecular weight When it is too small, the cohesive force of radiation irradiation becomes small, and picking failure or transfer failure is liable to occur at the time of pickup or transfer to the pickup tape. Further, if the molecular weight is too large, the film is peeled off or deviated from the adhesive tape.

Further, the molecular weight in the present invention means a weight average molecular weight in terms of polystyrene by a usual method.

Further, in the present invention, the amount of the photopolymerizable carbon-carbon double bond of the (meth)acrylic copolymer is preferably from 0.5 to 2.0 meq/g, more preferably from 0.8 to 1.5 meq/g. If the amount of the double bond is too small, the effect of lowering the adhesive force after radiation irradiation becomes small. If the amount of the double bond is too large, the fluidity of the adhesive after radiation irradiation is insufficient, and the element gap after the extension is insufficient, so that it is difficult to recognize the image of each element at the time of pickup. Further, the (meth)acrylic copolymer itself lacks stability and is difficult to manufacture.

Further, in the present invention, the gel fraction of the adhesive before curing may be adjusted according to the average molecular weight of the (meth)acrylic copolymer and the amount of the hardener blended, preferably 60% or more, more preferably 80. ~100%. When the gel fraction is too small, the cohesive force is lowered, so that the risk of sticking residue on the circuit on the front side of the wafer is increased. Further, when the (meth)acrylic copolymer has an OH group having a hydroxyl value of 5 to 100, the adhesion after radiation irradiation is reduced, whereby the risk of picking up errors can be further reduced, which is preferable. Further, when the (meth)acrylic copolymer has a COOH group having an acid value of 0.5 to 30, the belt recovery property is improved, whereby the used belt storage type mechanism can be easily handled, which is preferable. When the hydroxyl value of the (meth)acrylic copolymer is too low, the effect of lowering the adhesive force after radiation irradiation is insufficient, and if it is too high, the fluidity of the adhesive after radiation irradiation is impaired. Further, if the acid value is too low, the effect of improving the recovery property is not sufficient, and if it is too high, the fluidity of the adhesive is impaired.

In the case where the radiation curable adhesive of the present invention is cured by ultraviolet irradiation, a photopolymerization initiator such as isopropyl benzoin, isobutylbenzoin, benzophenone or rice may be used as needed. Its ketone, chloro 9-oxo (chlorothioxanthone), dodecyl 9-oxosulfur Dimethyl 9-oxosulfur Diethyl 9-oxosulfur Benzene dimethyl ketal, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethyl phenyl propane, and the like. The blending amount of the photopolymerization initiator is preferably 0.1 to 10 parts by mass based on 100 parts by mass of the (meth)acrylic copolymer. If the blending amount is too small, the reaction is insufficient, and if the blending amount is too large, the contamination is affected by an increase in low molecular components.

(gel fraction)

The gel fraction of the adhesive layer in the surface protective tape for film polishing of the present invention is preferably 80% or more. The gel fraction is preferably 85 to 95%.

If the gel fraction is too low, the problem of sticking of the paste tends to occur, and if the gel fraction is too high, the fluidity is lost and the adhesive properties are not exhibited.

The gel fraction can be measured in the following manner.

Two 100 mm × 120 mm test pieces were cut out from the adhesive tape before the film build-up, and the quality of the adhesive tape was measured as the quality of the adhesive layer after peeling off the separator. In a polypropylene container for the diameter of the test piece, the adhesive is placed face up and the pin is fixed by a pin, and 500 ml of toluene is placed in the container in such a manner that the test piece is immersed in the solution to prevent solvent. The mixture was volatilized and capped, and allowed to stand at 25 ° C for 24 hours.

After 24 hours, the solvent in the container was filtered through a metal sieve of sieve size #150 and discarded, and then dried in a container at a temperature of 25 ° C for 24 hours in a state where the tape was placed in the container, and the electrons were used 24 hours later. The balance measures the mass of the belt. The value calculated by the calculation formula shown below was set as the gel fraction.

Further, the quality of the base film is measured before the adhesive tape is formed, or after the adhesive tape is formed, the adhesive layer is peeled off by a solvent or the like, and the adhesive layer is removed and measured.

Gel fraction [%] = {(adhesive tape quality after solvent extraction - substrate film quality) / (adhesive tape quality before solvent extraction - substrate film quality)} × 100

<Binder layer>

The adhesive layer of the present invention is obtained by filming an adhesive in advance, and is also referred to as an adhesive film in the present specification. For example, any of the polyimine resin, polyamine resin, polyether quinone imide resin, polyamidoximine resin, polyester resin, polyester quinone imide resin, phenoxy oxide used in the adhesive can be used. Resin, polyfluorene resin, polyether oxime resin, polyphenylene sulfide resin, polyether ketone resin, chlorinated polypropylene resin, (meth)acrylic resin, polyurethane resin, epoxy resin, poly(methyl) acrylamide Resin, melamine resin, etc. or a mixture thereof.

The main component of the adhesive is preferably a (meth)acrylic resin {(meth)acrylic copolymer} or a phenoxy resin. Polyimine-based resin is excellent in structural reliability. However, since the glass transition temperature is high, in many cases, sufficient fluidity cannot be obtained at the time of bonding, and it is not suitable for the follow-up of bumps such as bumps. It is easy to cause air entrainment. On the other hand, the (meth)acrylic copolymer or the phenoxy resin can ensure the fluidity at the time of bonding and ensure the reliability at the time of constitution.

The polymerization method of the (meth)acrylic copolymer is not particularly limited, and examples thereof include pearl polymerization, solution polymerization, suspension polymerization, and the like, and a copolymer can be obtained by these methods. In the case of such a (meth)acrylic copolymer, for example, Paracron W-197C (manufactured by Kasei Kogyo Co., Ltd., trade name) is preferable.

Further, the (meth)acrylic copolymer preferably contains acrylonitrile. The content of acrylonitrile is preferably 10 to 50% by mass, and more preferably 20 to 40% by mass based on the (meth)acrylic copolymer. When the acrylonitrile is 10% by mass or more, the Tg of the adhesive layer can be increased to improve the adhesion. If it is too large, the fluidity of the adhesive layer may be deteriorated and the adhesion may be lowered. The (meth)acrylic copolymer containing acrylonitrile as a component is preferably synthesized by suspension polymerization.

The (meth)acrylic copolymer may have a functional group in order to improve the adhesion. The functional group is not particularly limited, and examples thereof include an amine group, an amine ester group, a quinone imine group, a hydroxyl group, a carboxyl group, and a glycidyl group. Among them, a glycidyl group is preferred. Epoxypropyl group and as a thermosetting resin The reactivity of the epoxy resin is good, and it is difficult to react with the adhesive layer when compared with a hydroxyl group or the like, so that it is difficult to cause a change in surface free energy. Examples of the (meth)acrylic copolymer having a glycidyl group include a glycidyl ether (meth)acrylic copolymer, a glycidylamine (meth)acrylic copolymer, and a glycidyl ester (methyl). The acrylic copolymer preferably contains at least one of these, and more preferably two or more.

The phenoxy resin may, for example, be a resin obtained by reacting a difunctional phenol with an epihalohydrin to a high molecular weight or by addition polymerization of a difunctional epoxy resin and a difunctional phenol. More specifically, the phenoxy resin can be obtained, for example, by reacting a difunctional phenol with an epihalohydrin in the presence of a catalyst such as an alkali metal hydroxide in a non-reactive solvent at a temperature of 40 to 120 ° C. . Further, the phenoxy resin can be used in the presence of a catalyst such as an alkali metal compound, an organophosphorus compound or a cyclic amine compound in the presence of a difunctional phenol resin, and a guanamine compound having a boiling point of 120 ° C or higher. In an organic solvent such as an ether, a ketone, a lactone or an alcohol, it is obtained by heating to 50 to 200 ° C under conditions of 50 parts by mass or less of the reaction solid content to carry out an addition polymerization reaction. The phenoxy resin may be used singly or in combination of two or more.

In the present invention, it is preferred to contain an epoxy resin in the composition of the adhesive layer. As such a preferred epoxy resin, a epoxy propyl group or a group having a partial structure in which an epoxy ring is formed on the alicyclic ring is preferred. Particularly preferred are epoxy propylene ether epoxy resins, epoxy propylamine epoxy resins, propylene acrylate epoxy resins, and alicyclic epoxy resins.

Among them, a resin which is substituted with a hydroxyl group (phenolic hydroxyl group) of a bisphenol resin is preferably used in any of the epoxy propyl group or a group having a partial structure having an epoxy ring condensed ring on the alicyclic ring.

Examples of such a bisphenol-based epoxy resin include a bisphenol A epoxy resin, a bisphenol F epoxy resin, a bisphenol AD epoxy resin, and a bisphenol S epoxy resin.

Among these bisphenol-based epoxy resins, a bisphenol F epoxidized propylene ether resin and a bisphenol A epoxidized propylene ether resin are preferable.

In the present invention, it is particularly preferred to combine two or more bisphenol-based epoxy trees having different structures. For grease use, it is best used in combination with bisphenol F epoxidized propyl ether resin and bisphenol A epoxidized propyl ether resin.

By using a bisphenol-based epoxy resin having a different structure among two or more types of epoxy resins, fluidity for embedding irregularities such as bumps and hardenability for bonding reliability can be simultaneously achieved.

The blending amount of the epoxy resin in the adhesive layer is preferably from 15 to 35 mass% of the entire resin.

The subsequent layer may also contain an inorganic filler. When the amount of addition is large, the fluidity is lowered and the adhesiveness is lowered. Therefore, the content of the inorganic filler is preferably less than 60 parts by mass, more preferably 50 parts by mass or less, still more preferably 30 parts by mass, per 100 parts by mass of the resin component. the following. Further, when the particle diameter is large, irregularities are formed on the surface of the adhesion surface, and the adhesiveness is lowered. Therefore, the average particle diameter of the inorganic filler is preferably less than 1 μm, more preferably less than 0.5 μm, and still more preferably less than 0.1 μm. The lower limit of the particle diameter of the inorganic filler is not particularly limited, but is actually 0.003 μm or more. The inorganic filler may have insulating properties and thermal conductivity, and examples thereof include nitrogen compounds (boron nitride, aluminum nitride, tantalum nitride, carbon nitride, titanium nitride, etc.), and carbon compounds (tantalum carbide, carbonized fluorine). , boron carbide, titanium carbide, tungsten carbide, diamond, etc.), metal oxides (cerium oxide, aluminum oxide, magnesium oxide, zinc oxide, antimony oxide, etc.).

By controlling the surface free energy difference, the subsequent layer can be used for wafer processing which has a sufficient adhesive layer even if it is peeled off after bonding to the adhesive layer. Surface protection tape.

Further, in the surface protection tape for film polishing of the present invention, the surface free energy of the adhesive layer is preferably 25 to 45 mN/m. If the surface free energy is too small, the wettability is insufficient, so that voids are likely to occur and the reliability of the structure is deteriorated. On the other hand, if it is too large, it is firmly adhered to the adhesive tape, so that it cannot be transferred to the pickup tape or a pickup failure occurs.

The surface layer free energy of the layer is preferably 30-40 mN/m, more preferably 30-40 mN/m, and the difference between the surface free energy of the adhesive layer is 10 mN/m or less.

Surface free energy can be changed by changing the structure of the resin as the main component of the film Adjust by type or blending amount. Further, it may be adjusted at the time of coating depending on drying conditions or by adding an additive such as a surfactant.

The surface free energy can be measured in the following manner.

(Measurement of surface free energy)

In the present invention, the surface free energy of the adhesive layer is preferably 25 to 45 mN/m as described above. The surface free energy of the subsequent layer can be determined by measuring the contact angle θ using a contact angle meter, for example, a FACE contact angle meter CA-S150 (trade name) manufactured by Kyowa Chemical Co., Ltd. The evaluation conditions at this time were droplet volume: 2 μL of water and 3 μL of diiodomethane, and the reading time was 30 seconds after the dropwise addition. The surface free energy is calculated and calculated by substituting the value of the contact angle into the following equation.

γ _s : surface free energy : Polar component of surface free energy

: Dispersed components of surface free energy

θ ^H : contact angle of water with respect to the fixed surface

θ ¹ : contact angle of methyl iodide relative to the fixed surface

(molecular weight)

In the present specification, the molecular weight means a weight average molecular weight, which is measured by a gel permeation chromatography (GPC) method and using a calibration curve based on standard polystyrene.

[Measurement conditions by GPC method]

Machine: High-speed liquid chromatography LC-20AD [manufactured by Shimadzu Corporation, trade name]

Pipe column: Shodex Column GPC KF-805 [manufactured by Shimadzu Corporation, trade name]

Dissolved solution: chloroform

Measuring temperature: 45 ° C

Flow rate: 3.0ml/min

RI detector: differential refractive index detector RID-10A [manufactured by Shimadzu Corporation, trade name]

(acid value)

The acid value was determined in accordance with 11.1 of JIS K 5407.

(a) reagent

‧Bromoquinol blue indicator

‧0.01N potassium hydroxide-ethanol solution

‧Acetone reagent level

(b) operation

Approximately 10 g of the sample was properly weighed into an Erlenmeyer flask, dissolved in 50 ml of acetone, and 3 to 4 drops of bromoquinol blue indicator were added. It was titrated with a 0.01 N potassium hydroxide-ethanol solution.

(c) Calculation

The acid value was determined by the following formula.

V: 0.01N potassium hydroxide-ethanol solution titration (ml)

f: 0.01 N potassium hydroxide-ethanol solution factor

S: sample take amount

(hydroxyl value)

The measurement of the hydroxyl value was carried out in accordance with JIS K 0070.

(a) reagent

‧Acetylation reagent (acetic anhydride-pyridine)

‧N/2 potassium hydroxide-ethanol solution

(b) operation

After the sample was acetylated with an acetamidine reagent, the excess acetic acid was titrated with a N/2 potassium hydroxide-ethanol solution.

(c) Calculation

The hydroxyl value was determined by the following formula.

V: titration of the N/2 potassium hydroxide-ethanol solution of this test (ml)

VB: titration of the N/2 potassium hydroxide-ethanol solution of the control test (ml)

F: N/2 potassium hydroxide-ethanol solution factor

S: sample take amount (g)

AV: acid value of the sample (mgKOH/g)

(elastic modulus)

The adhesive layer can improve the adhesion to the uneven surface of the bump or the like by controlling the elastic modulus. In the surface protection tape for film polishing of the present invention, the elastic modulus at 25 ° C after curing of the adhesive layer is preferably in the range of 1 to 1000 MPa, more preferably 1 MPa or more and 10 MPa or less. Further, the elastic modulus of the adhesive layer at 250 ° C is preferably in the range of 1 to 1000 MPa. Further, the elastic modulus of the adhesive layer at 25 ° C and the elastic modulus at 250 ° C are preferably 100 or less. That is, even if the modulus of elasticity increases due to hardening, (the modulus of elasticity after hardening) ÷ (the modulus of elasticity before curing) is preferably 100 or less. Then, the film must have excellent embedding property before bonding, and thus it is set to have low elasticity. Then, it is hardened at the time of the subsequent contact with the substrate, but at this time, when the elastic modulus is too high, the warpage is large and the warpage of the wafer is caused. When the modulus of elasticity is too low, it is not sufficiently hardened, so the reliability of the structure is lacking. Moreover, in general, reflow soldering is performed for the package after the wafer and the substrate. deal with. Therefore, it is preferable to have an equivalent elastic modulus at the reflow heating temperature, and it is preferable to change the elastic modulus before and after heating to be small. More preferably, the change in the modulus of elasticity at 25 ° C and the modulus of elasticity at 250 ° C (absolute value of the difference) is 100 or less.

The modulus of elasticity can be measured in the following manner.

The elastic modulus measurement was carried out using a viscoelasticity measuring apparatus ARES (trade name) manufactured by Rheometric Scientific FE Co., Ltd. Measuring plate system using diameter 8mm Board, film adhesive is laminated and utilizes 8mm The puncher is used for punching a hole having a thickness of about 1 mm. The measurement conditions were set to 25 ° C at normal temperature, 250 ° C, and a frequency of 1 Hz. Further, the temperature rise condition at the time of measurement at 250 ° C was carried out at 10 ° C / min.

(saturated moisture absorption rate)

The saturated moisture absorption rate of the subsequent layer is preferably 1.5% by volume or less, more preferably 1.0% by volume or less. The lower limit of the saturated moisture absorption rate is not particularly limited, and is usually 0% by volume or more. When an isocyanate-based curing agent is used for the curing agent, there is a possibility of reacting with water to change the crosslinked structure, and the reason is that if the water-absorbent adhesive layer is cured by heating, it is generated. Bubbles caused by evaporation of moisture cause problems such as poor appearance or insufficient adhesion.

The method for measuring the saturated moisture absorption rate is as follows.

A circular film-shaped adhesive layer (adhesive film) having a diameter of 100 mm was set as a sample, and the sample was dried in a vacuum dryer at 120 ° C for 3 hours, placed in a desiccator and cooled, and then the dry mass was measured and set. For M1. The sample was taken out in a constant temperature and humidity chamber at 85 ° C and 85% RH, and taken out. When the sample was quickly weighed and the weighing value became constant, the mass was set to M2.

The saturated moisture absorption rate (% by volume) was calculated from the density (d) of the adhesive (the film-like adhesive layer), the dry mass (M1), and the moisture absorption mass (M2) by the following formula.

Saturated moisture absorption rate (% by volume) = [(M2-M1) / (M1/d)] × 100

The subsequent agent layer is preferably a hardening agent containing a compound having a functional group crosslinked with an isocyanate-based hardener or an epoxy-based hardener and having a flux function.

The flux is usually a material for improving the wettability of the bump. As a material having a flux function, a rosin-based material is usually preferably used.

In the present invention, the effect of removing the oxide film on the surface of the solder is not particularly limited, and it is preferably a compound having a carboxyl group or a phenolic hydroxyl group or a compound of a carboxyl group and a phenolic hydroxyl group, and more preferably used. A compound having both a carboxyl group and a phenolic hydroxyl group is used as a curing agent.

Examples of the compound having a phenolic hydroxyl group having flux activity include phenols. Specific examples thereof include phenol, o-cresol, 2,6-xylenol, p-cresol, m-cresol, and o-B. Phenolic, 2,4-xylenol, 2,5-xylenol, m-ethylphenol, 2,3-xylenol, 2,4,6-trimethylphenol (mesitol), 3,5-dimethyl Phenol, o-tertiary butyl phenol, catechol, o-tertiary pentylphenol, resorcinol, p-octylphenol, p-phenylphenol, bisphenol A, bisphenol F, bisphenol AF, biphenol A monomer containing a phenolic hydroxyl group such as diallyl bisphenol F, diallyl bisphenol A, trisphenol or tetraphenol.

Examples of the curing agent having a flux function include a curing agent for an epoxy resin, an aliphatic dicarboxylic acid, and an aromatic dicarboxylic acid.

More specifically, the curing agent having a flux function includes, for example, two or more phenolic hydroxyl groups which can be added to the epoxy resin in one molecule, and a fragrance which acts on the flux (reduction). A compound in which one or more carboxyl groups are directly bonded to each other. As such a hardener having flux activity, 2,3-dihydroxybenzoic acid, 2,4-dihydroxybenzoic acid, gentisic acid (2,5-dihydroxybenzoic acid), 2,6- Benzoic acid derivatives such as dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, gallic acid (3,4,5-trihydroxybenzoic acid); 1,4-dihydroxy-2-naphthoic acid, 3, a naphthoic acid derivative such as 5-dihydroxy-2-naphthoic acid or 3,7-dihydroxy-2-naphthoic acid; a reduced phenolphthalein; and a bisphenolic acid; and these may be used alone or in combination of two or more.

The blending amount of the hardener (crosslinking agent) having flux activity is preferably 0.5 to 30 parts by mass, more preferably 1 to 10 parts by mass, per 100 parts by mass of the resin component of the adhesive layer.

<<Manufacturing method of semiconductor wafer>>

Hereinafter, a method of manufacturing a semiconductor wafer using the surface protective tape for film polishing of the present invention will be described.

The semiconductor wafer manufacturing method of the present invention is based on a semiconductor wafer on which a semiconductor circuit is formed, and after forming a modified layer in a bump-attached wafer having bumps as electrodes, the back surface of the semiconductor wafer is polished and once Dividing into individual wafers, and having the following steps: after forming the modified layer and polishing the back surface of the semiconductor wafer, an adhesive layer is laminated on the adhesive layer of the adhesive tape having the adhesive layer on the substrate film a surface protection tape for film polishing (also referred to as a surface protection tape), which is attached to a side of a semiconductor wafer on which a semiconductor circuit is formed with the above-mentioned adhesive film side; and when picking up after polishing the back surface of the semiconductor wafer Or, when transferring to the tape for pickup, it is assumed that only the adhesive film is in the state of the wafer.

In the present invention, it is preferable to carry out the step of directly picking up from the surface protective tape without using a transfer film (pickup tape) in the step of merely adhering the film to the state of the wafer.

Further, it is preferable to include a step of simultaneously dividing the adhesive film and the wafer by stretching the surface protective tape for film polishing.

Further, after the wafer is once cut by back surface polishing of the semiconductor wafer, it is preferable to divide only the above-mentioned film of the surface protective tape for film polishing by laser.

Hereinafter, a more preferable method of manufacturing a semiconductor wafer of the present invention will be described by using a diagram. The same symbols in the various figures represent the same components.

In the method of manufacturing a semiconductor wafer, there are the following methods: a process of transferring to a pickup tape; and a process of not performing transfer to the pickup tape.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view schematically showing the first half of the process of the preferred method of fabricating the semiconductor wafer of the present invention, the method of transferring to the process of the pickup tape, and the transfer to the pickup tape The process of the process is common to the previous half process.

2 is a process after the process of transferring to the pick-up tape in the process of (4) of FIG. In the latter half of the process, FIG. 3 is an example of a process in which the process of the process of transferring to the pickup tape is performed in the process of the process of (4) of FIG.

[I] Transfer to the pick-up tape process

Hereinafter, description will be made using FIGS. 1 and 2 .

(1) First, a modified layer (2) is formed from a front surface (1A) of a semiconductor wafer (1) by using a laser (7).

In order to divide the semiconductor wafer into semiconductor wafers, the predetermined portion of the semiconductor wafer is irradiated with laser light, and the modified region {modified portion (2A)} is formed inside the semiconductor wafer by multiphoton absorption.

The phenomenon of optical damage due to multiphoton absorption is caused by the irradiation of the laser light, and thermal strain is induced inside the semiconductor wafer due to the optical damage, thereby forming a modified region (cracked region) inside the semiconductor wafer. ) (2A). As the laser light (laser light) used in this case, there are Nd:YAG laser, Nd:YVO laser, Nd:YLF laser, titanium sapphire laser, etc. which generate pulsed laser light.

The thickness of the modified layer (2) is preferably set to 20 μm to 40 μm. Further, the modified layer is preferably provided, for example, at 10 μm to 50 μm of the final polishing thickness. The reason for this is that when the modified portion is contained in the wafer, there is a possibility that the bending strength of the portion is lowered. Further, by providing the modified layer more than the final polishing thickness, the wafer can be cut by the impact when the modified layer is polished.

(2) The surface protection tape (surface protection tape) for film polishing of the present invention is bonded to the front surface (1A) of the semiconductor wafer.

At this time, the adhesive layer (attachment film) (6) of the surface protective tape for film polishing is attached to the side of the semiconductor wafer (1) where the modified layer (2) is formed. As described above, the surface protective tape of the present invention has an adhesive layer (5) on the base film (4) and an adhesive layer (adhesive film) (6) on the adhesive layer. Among them, the tape having the adhesive layer (5) on the base film (4) is also referred to as an adhesive tape (3).

(3) Polishing the surface (back surface) (1B) of the semiconductor wafer opposite to the surface on which the surface protective tape for film polishing is bonded. In the figure, 8 is a grinder, and 9 is a wafer in back grinding.

(4) The back grinding is finished in a state where it can be ground to a target thickness. In the figure, 10 is a wafer in which the back surface is ground.

(5-1) The pickup tape (11) is attached to the back surface (polishing surface) of the semiconductor wafer, and is fixed to the ring frame (12).

The pick-up tape requires good pick-up and extensibility in the pick-up step, so it is preferable to use a dicing tape.

As the adhesive for the adhesive layer of the dicing tape, a usual adhesive used for the dicing tape can be used, and an adhesive which is hardened by irradiation with ultraviolet rays is preferably used.

The ring frame can be used by the user of the conventional semiconductor wafer processing steps.

(6-1) Only the adhesive tape (3) (the base film (4) and the adhesive layer (5)) of the surface protective tape for film polishing is peeled off, so that only the adhesive film (6) remains on the front surface of the wafer. In the figure, in the case of using an ultraviolet curing type as an adhesive, the state in which the adhesive tape (3) is peeled off after ultraviolet irradiation (not shown) is shown.

(7-1) Extend the pickup belt.

In this case, there are two extension methods, (7-1A) dividing the adhesive film (adhesive layer) and the semiconductor wafer, or (7-1B) cutting the semiconductor wafer and cutting off the laser (14). Next the film (adhesive layer).

To perform the above (7-1A) or (7-1B), it can be adjusted by changing the extension conditions.

That is, in the case where the film is stretched and divided (7-1A), a certain amount of elongation is required, so that the wafer can be simultaneously divided by generally increasing the amount of stretching. On the other hand, in the case of only the extension of the wafer (7-1B), since the wafer is a rigid body, the amount of extension can be reduced. By adjusting the amount of extension arbitrarily as described above, it is possible to set the state of (7-1A) or (7-1B).

In the figure, 6A denotes a divided adhesive layer (following film), and 10A denotes a divided wafer. Also, 11A denotes an extended pickup belt, and 13 denotes an expander.

(8-1) The divided semiconductor wafer (10A) is a singulated wafer (17) to which an adhesive film (adhesive layer) (6A) is attached, and is bonded to an adhesive film (adhesive layer) ( 6A) Pick up together. In the figure, 15 denotes a pick-up needle, and 16 denotes a pick-up collet. The wafer (17) is peeled off from the pickup tape (11A) and picked up.

[II] Process for transferring to the pickup belt

Hereinafter, description will be made using FIGS. 1 and 3. Further, (1) to (4) are the same as the above-described process of transferring to the pickup belt [I].

(1) First, a modified layer (2) is formed from a front surface (1A) of a semiconductor wafer (1) by using a laser (7).

(2) The surface protection tape (surface protection tape) for film polishing of the present invention is bonded to the front surface of the semiconductor wafer. At this time, the adhesive layer (attachment film) (6) of the surface protective tape for film polishing is attached to the side of the semiconductor wafer (1) where the modified layer (2) is formed.

(3) Polishing the surface (back surface) (1B) of the semiconductor wafer opposite to the surface on which the surface protective tape for film polishing is bonded.

(4) The back grinding is finished in a state (10) in which the target thickness can be ground.

(5-2) A fixing tape (21) is attached to the base film (4) side of the surface protective tape surface for film polishing, and is fixed to the annular frame (22).

Here, the fixing belt (21) is substantially the same as the above-described dicing belt (pickup belt (11)).

(6-2) The fixing belt (21) is extended. At this time, on the adhesive film (3), both the film (adhesive layer) (6) and the semiconductor wafer (1) are divided.

The extension is preferably a speed of 0.5 to 5 mm/sec and an extension of 5 to 20 mm.

In the figure, 6A denotes a divided adhesive layer (following film), and 10A denotes a divided wafer. Further, 21A denotes an extended fixing belt, and 23 denotes an expander.

(7-2) The divided semiconductor wafer (10A) is a singulated wafer (27) to which an adhesive film (adhesive layer) (6A) is attached, and is bonded to an adhesive film (adhesive layer) ( 6A) Pick up together. In the figure, 25 denotes a pick-up needle, and 26 denotes a pick-up collet. The wafer (27) is peeled off from the adhesive layer (5) of the adhesive film (3) and picked up. In the figure, in the case of using an ultraviolet curing type as an adhesive, the wafer (27) is peeled off from the adhesive layer (5) after ultraviolet irradiation (not shown).

The method for producing a surface protective tape for film polishing according to the present invention exhibits a remarkable effect in the case of performing film polishing on a wafer having irregularities such as bumps as electrodes.

By using the manufacturing method of the present invention, the dicing step after back grinding can be omitted. Moreover, by using the surface protective tape for film polishing of the present invention, the step of flowing the primer can be omitted, so that the resin leakage due to the primer is not caused, and the yield is improved.

As an important performance in the thin film formation of a wafer, the bending strength of a wafer can be mentioned. In the method of performing dicing after back grinding as a usual method, whether the dicing by the blade or the dicing by the laser is a step of damaging the semiconductor wafer to be a thin film, it is easy to be The resulting wafer has residual damage, chipping or, in the worst case, wafer breakage. On the other hand, by using the manufacturing method of the present invention, damage to the semiconductor wafer can be minimized, the bending strength of the wafer can be improved, and wafer cracking is less likely to occur, so that the package reliability can be ensured.

When the semiconductor wafer is mounted on a substrate, the thin film semiconductor wafer, in particular, having irregularities such as bumps is pressure-bonded, so that wafer cracking is very likely to occur. On the other hand, by using the manufacturing method of the present invention, the bonding film (the adhesive layer) is subsequently mounted in the state of the semiconductor wafer, so that the occurrence of wafer cracking can be suppressed. Further, it is possible to carry out the use of the adhesive film (adhesive) at the same time as the constitution, so that the manufacturing time can be shortened.

In the present invention, it is also possible to transfer the semiconductor device to the pickup tape after wafer formation, and to manufacture the semiconductor device in another step of picking up only (steps of FIGS. 1 and 2), but preferably without transfer. Pick up (steps in Figures 1, 3). By picking up without transfer, the peeling step of the adhesive tape can be omitted, and the stress can be released from the applied stress during peeling, so that damage to the semiconductor wafer can be reduced.

In the present invention, the wafer may be divided by a wafer pressing roller after the film is polished (not shown), or the wafer may be divided by pressing the pressing blade from the modified layer (not shown). The wafer division can also be performed by extension (step (7-1A) of Fig. 2, step (6-2) of Fig. 3). Since the stress from the outside is not applied, it is preferable to perform the division by extension.

[Examples]

Hereinafter, the present invention will be described in further detail based on examples, but the present invention is not limited thereto.

Example 1

(I) Fabrication of surface protection tape for film polishing

An ultraviolet curable (meth)acrylic adhesive layer is provided on a substrate film made of an ethylene-acrylic acid copolymer having a thickness of 100 μm, and (meth)acrylic acid containing epoxy resin is provided on the adhesive layer. The adhesive layer formed of the copolymer is used to produce the surface protective tape for film polishing of the present invention.

(1) Manufacturing method of adhesive tape

Blending 78 mol% of 2-ethylhexyl acrylate, 21 mol% of 2-hydroxyethyl acrylate, and 1 mol% of methacrylic acid, and copolymerizing the same in an ethyl acetate solution, thereby obtaining a copolymer having a weight average molecular weight of 700,000. Solution. 5.0 parts by mass of 2-methylpropenyloxyethyl isocyanate (trade name, Karenz MOI manufactured by Showa Denko Co., Ltd.) was mixed with the solution in an amount of 100 parts by mass of the copolymer, and was made in the solution. In such a reaction, a hydroxyl group derived from a side chain of the copolymer is added to a double bond-containing group derived from the above isocyanate, whereby an acrylic copolymer polymer having a double bond-containing group is synthesized.

To 100 parts by mass of the acrylic copolymer polymer having the double bond-containing group, 6.0 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.), which is a hardener, is used as a photoreaction initiator Irgacure 184. (trade name, manufactured by BASF Corporation) 5.0 parts by mass, and an adhesive composition was obtained.

The obtained adhesive composition was applied to a release liner so that the thickness of the adhesive layer became 20 μm thick, and adhered to a 100 μm-thick ethylene-based ionic polymer resin on the side of the adhesive layer ( A product film having a thickness of 100 μm obtained by filming Himilan manufactured by Du Pont-Mitsui Polychemicals Co., Ltd. was obtained to obtain an adhesive tape.

(2) Method for manufacturing adhesive layer and surface protective tape

An acrylic resin was obtained by copolymerizing 40 mol% of butyl acrylate, 30 mol% of ethyl acrylate, and 30 mol% of acrylonitrile in a mixed solution of ethyl acetate and toluene.

A mixed solution of ethyl acetate and toluene was blended with 50 mol% of dicyandiamide and 50 mol% of a bisphenol F-type epoxy resin, and the copolymerization was carried out, whereby a hardened epoxy resin was obtained.

A phenoxy resin was obtained by blending 35 mol% of a bisphenol A type epoxy resin, 35 mol% of a bisphenol A type phenoxy resin, and 30 mol% of bisphenol A diglycidyl ether, and copolymerizing the same.

30 parts by mass of the obtained acrylic resin, 50 parts by mass of the cured epoxy resin, and 20 parts by mass of the phenoxy resin were blended and mixed in an ethyl acetate solution. To the solution, 5 parts by mass of cerium oxide particles having an average particle diameter of 5 μm which is an inorganic filler are blended in the solution to obtain 100% by mass of the obtained mixed resin to obtain an adhesive composition.

The obtained adhesive composition was applied onto a release liner such that the thickness of the adhesive layer became 70 μm thick, and the adhesive tape was peeled off from the release liner on the adhesive layer side. The adhesive layer is bonded to the side to obtain a surface protection tape for film polishing. This release liner was peeled off and used at the time of use.

(II) Manufacturing of semiconductor wafers

A semiconductor wafer is fabricated by the processes of FIGS. 1 and 2.

(1) The laser light (7) is irradiated from the back surface (1A) of the semiconductor wafer (1) using DAL7360 (trade name, Stealth Dicing device manufactured by Disco Co., Ltd.) at a diameter of 300 mm (about 12 inches).吋) The bump-attached wafer forms a modified layer (2). The size and spacing of the bumps are below.

Bump height: 80μm, pitch: 160μm, type of bump: solder

Thickness of the modified layer {modified part (2A)}: 30μm

(2) The front surface (1A) of the modified layer is provided on the semiconductor wafer, and the surface protective tape for film polishing prepared in the above is bonded to the side of the adhesive layer (6).

(3) Using DGP8761 (trade name, back grinding device manufactured by Disco Co., Ltd.), the surface (back surface) (1B) of the semiconductor wafer opposite to the surface on which the surface protective tape for film polishing is bonded is polished to the polishing. The thickness of the latter is 75 μm.

(4) After the polishing, the pickup tape (11) is attached to the back surface (polishing surface) of the semiconductor wafer (10), and is fixed to the annular frame (12).

Further, the pickup tape (11) uses a dicing tape having a base film formed of polyolefin and having a thickness of 110 μm. The dicing tape has an adhesive layer composed of an ultraviolet curable acrylic copolymer on the base film.

(5) After the ultraviolet irradiation, the surface protection tape for film polishing only peels the adhesive tape (3) (the base film (4) and the adhesive layer (5)) so that only the film (adhesive layer) is attached (6). ) remains on the front side of the semiconductor wafer.

(6) The pickup tape (11) was stretched under the conditions of a speed of 1 mm/sec and an extension of 20 mm so that the adhesive film (adhesive layer) and the polished semiconductor wafer were divided. {Step (7-1A) shown in Figure 2. }

(7) The divided semiconductor wafer (10A) becomes a singulated wafer (17) with an adhesive film (adhesive layer) (6A), and is bonded to the adhesive film (adhesive layer) (6A) Pick up together.

Example 2

Using the surface protection tape for film polishing produced in Example 1, the process of (6) in the first embodiment is changed to the following processes (6-1) to (6-2), and A semiconductor wafer was produced in the same manner as in the first embodiment.

(6-1) The pickup tape (11) was stretched at a speed of 1 mm/sec and an extension of 8 mm so that only the semiconductor wafer was divided.

(6-2) After the above extension, the adhesive film (adhesive layer) (6) is cut by the laser light (14). {Steps shown in Figure 2 (7-1B)}

Example 3

A semiconductor wafer is fabricated by the processes of FIGS. 1 and 3.

Using the surface protection tape for film polishing produced in Example 1, after the processes of (1) to (3) in Example 1, the following processes (4A) were performed instead of (4) to (7). (6A), manufacturing a semiconductor wafer.

(4A) The extension tape (11) (fixing tape (21)) similar to that of the first embodiment is attached to the base film (4) side of the surface protection tape for film polishing, and is fixed to the ring frame (22). . The extending tape (11) (fixing tape (21)) is attached to a base film made of a vinyl ionomer resin, and has an adhesive layer composed of an ultraviolet curable acrylic copolymer.

(5A) The fixing tape (21) was stretched under the conditions of a speed of 1 mm/sec and an extension of 20 mm to divide the adhesive film (adhesive layer) (6) from the semiconductor wafer on the adhesive film (3).

(6A) The divided semiconductor wafer (10A) becomes a singulated wafer (27) with an adhesive film (adhesive layer) (6A), and after the ultraviolet irradiation, the self-adhesive layer (5) The wafer (27) is picked up together with the adhesive film (adhesive layer) (6A).

Comparative example 1

(I) Method for manufacturing a surface protection tape for a bump

Blending 20 mol% of methacrylic acid, 30 mol% of 2-ethylhexyl acrylate, 10 mol% of 2-hydroxyethyl acrylate, 40 mol% of methyl acrylate, and copolymerizing in ethyl acetate solution This gave a copolymer solution having a weight average molecular weight of 600,000.

In the copolymer solution, 100 parts by mass of a pentafunctional urethane amide oligomer blended with a UV reactive resin, 10 parts by mass of a trifunctional urethane amide oligomer, and two with respect to 100 parts by mass of the copolymer. 30 parts by mass of a functional urethane amide oligomer, Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) as a curing agent, 4.0 parts by mass, Irgacure 184 as a photoreaction initiator (trade name, manufactured by BASF Corporation) 5 parts by mass of Ebecryl 350 (trade name, manufactured by Daicel-Allnex Co., Ltd.) as an additive was 0.5 parts by mass to obtain an adhesive composition.

The obtained adhesive composition was applied onto a release liner in such a manner that the thickness of the adhesive layer was changed to 130 μm, and bonded to a 100 μm thick LDPE (low density polyethylene) film to obtain a 230 μm thick prior convex. The block uses a surface protection tape. This release liner was peeled off and used at the time of use.

(II) Manufacturing of semiconductor wafers

The front surface of the 12-inch wafer with a solder bump having a height of 80 μm and a pitch of 160 μm was peeled off with a release liner and adhered to the adhesive layer side, and DGP8761 (trade name, Disco) was used. The back grinding device manufactured by the company, grinding the back of the wafer. This back grinding was performed until the wafer thickness after polishing was 75 μm.

Thereafter, the wafer with the surface protection tape for bumps was mounted on a polyolefin dicing tape having a thickness of 110 μm, and after UV irradiation, the surface protection tape for bumps was peeled off.

The crystal was cut using DFD6361 (trade name, a blade dicing apparatus manufactured by Disco Co., Ltd.), and picked up using DB800-HL (trade name, pick-up die-cutting machine manufactured by Hitachi High-Technologies Co., Ltd.).

The substrate was coated with U8443 (trade name, a flip chip primer manufactured by Namics Co., Ltd.) as an adhesive (NCP), and the wafer picked up therefrom was bonded to the substrate and sealed.

Comparative example 2

On the front side of a 12-inch wafer having solder bumps having a height of 80 μm and a pitch of 160 μm, the same surface protection tape for bump polishing as that prepared in Comparative Example 1 was peeled off with a release liner and an adhesive. The layer side was bonded, and the back surface of the wafer was polished using DGP8761 (trade name, back grinding device manufactured by Disco Co., Ltd.). This back grinding was performed until the thickness after polishing was 75 μm thick.

Thereafter, the wafer with the surface protection tape for bumps was subjected to a dicing tape of polyolefin having a thickness of 110 μm, and after the ultraviolet irradiation, the surface protection tape for the bump was peeled off.

The crystal was cut using DFL7160 (trade name, laser dicing apparatus manufactured by Disco Co., Ltd.), and picked up using DB800-HL (trade name, pick-up die-cutting machine manufactured by Hitachi High-Technologies Co., Ltd.).

The picked wafer was bonded to the substrate, and U8443 (trade name, a primer for flip chip manufactured by Namics Co., Ltd.) as a primer was laterally flowed and sealed.

The following characteristics were evaluated for the semiconductor wafers obtained in the above respective examples and comparative examples.

(1) Whether the wafer is broken or not

It was visually observed whether or not cracking occurred on the wafer at the time of the above extension, and evaluation was performed on the following basis.

○ (good): The wafer is not broken.

△ (bad): A slight crack in the wafer was observed.

× (especially bad): Obvious wafer cracking can be seen.

(2) Then the presence or absence of burr

It was visually observed whether or not a burr was generated at the time of the above extension and at the time of picking up, and evaluation was performed on the following basis.

No (good): I can't see the burr.

Yes (bad): You can see the burr.

The above results are shown in Table 1 together with the presence or absence of the primer step.

As described above, in the method of manufacturing the semiconductor wafer of the first to third embodiments, since the unevenness of the bump is completely buried by the adhesive layer, when the wafer having the bump as the electrode is subjected to the film polishing. It does not cause cracking and the like, and exhibits good abrasiveness. Further, the dicing step after back grinding can be omitted, and the step of flowing into the primer can be omitted by using the surface protective tape for film polishing, and there is no primer. As a result, the resin leaks out, so the yield is improved.

Further, by using the manufacturing method of the present invention, damage to the semiconductor wafer can be minimized, the bending strength of the wafer can be improved, and wafer cracking is less likely to occur, so that the package reliability can be ensured.

Further, since the bonding film (adhesive layer) is subsequently mounted in the state of the semiconductor wafer, the occurrence of wafer cracking can be suppressed, and the use of the adhesive can be achieved at the same time as the bonding, so that the manufacturing time can be shortened.

Further, in the third embodiment, since the pickup is performed without transfer, the peeling step of the adhesive tape can be omitted, and the stress applied from the application at the time of peeling can be released, so that the damage to the semiconductor wafer can be further reduced.

On the other hand, in Comparative Examples 1 and 2, the adhesive agent overflowed from the wafer to cause subsequent burrs. In particular, the UF (primer) method has a large amount of overflow.

In the comparative examples 1 and 2, the dicing using the blade and the laser was performed separately, so that chipping on the side of the wafer was generated, especially in the blade dicing mode, which caused wafer defect or wafer breakage. The result of the crack.

In Examples 1 to 3, the gel fraction of the adhesive layer was 80% or more.

On the other hand, in the case of the other comparative example, when the gel fraction of the adhesive layer is less than 80%, the cohesive force is lowered in the comparative example, so that a paste remains on the circuit on the front side of the wafer, thereby becoming Bad results.

In Examples 1 to 3, the film had a modulus of elasticity at 250 ° C of 10 MPa or less and a saturated moisture absorption rate of 1.5 % by volume or less.

On the other hand, as another comparative example, when the elastic modulus of the film at 250 ° C exceeds 10 MPa, and/or the saturated moisture absorption rate exceeds 1.5 vol%, the warpage is large in the comparative examples to cause warpage of the wafer. The song, or the problem of poor appearance or insufficient adhesion, has become a bad result.

In Examples 1 to 3, the surface free energy of the film was 25 to 45 mN/m.

On the other hand, as another comparative example, when the surface free energy of the film is less than 25 mN/m or more than 45 mN/m, the wettability is insufficient in the comparative examples, so that voids or poor reliability of the structure are caused. As a result, they all become bad results.

The present invention has been described in connection with the embodiments thereof, and the present invention is not limited to the details of the present invention, as long as it does not violate the scope of the patent application. The invention should be interpreted to the fullest extent within its spirit and scope.

The present invention claims to be based on the priority of Japanese Patent Application No. 2012-254703, filed on Nov. 20, 2012, the entire disclosure of which is hereby incorporated by reference.

Claims (13)

A method of manufacturing a semiconductor wafer, after forming a modified layer in a bump-attached semiconductor wafer having a semiconductor circuit and having bumps as electrodes, grinding the back surface of the semiconductor wafer and dividing the wafer into individual wafers at a time The method comprises the steps of: after forming the modified layer and before polishing the back surface of the semiconductor wafer, laminating a film formed by laminating an adhesive layer of an adhesive tape having an adhesive layer on a substrate film; Using a surface protection tape on the side of the semiconductor wafer on which the semiconductor circuit is formed, and when picking up after polishing the back surface of the semiconductor wafer, or when transferring to a tape for picking, It is assumed that only the bonding film is in the state of the wafer. The method of manufacturing a semiconductor wafer according to the first aspect of the invention, wherein the step of attaching only the bonding film to the state of the wafer is a step of directly picking up the surface protective tape without using a transfer film. . A method of manufacturing a semiconductor wafer according to claim 1 or 2, comprising the step of simultaneously dividing the adhesive film and the wafer by extending the surface protective tape for film polishing. The method of manufacturing a semiconductor wafer according to claim 1 or 2, wherein after the wafer is once diced by back surface polishing of the semiconductor wafer, only the surface protection tape for polishing the film is irradiated by laser The film is divided. A surface protection tape for film polishing is formed by laminating a film on an adhesive layer having an adhesive layer of an adhesive layer on a base film, wherein the adhesive film has an elastic modulus of less than 10 MPa at 250 ° C. The saturated moisture absorption rate is 1.5% by volume or less, and is composed of a single or plural layer containing at least one selected from the group consisting of a (meth)acrylic copolymer and a phenoxy resin as a binder. The surface protection tape for film polishing according to claim 5, wherein the adhesive layer is an ultraviolet curing type. The surface protection tape for film polishing according to the fifth or sixth aspect of the invention, wherein the adhesive layer is mainly composed of a (meth)acrylic copolymer, and the gel fraction is 80% or more. The surface protection tape for film polishing according to any one of claims 5 to 7, wherein the adhesive film has a surface free energy of 25 to 45 mN/m and a saturated moisture absorption rate of 1.5% by volume or less. The surface protection tape for film polishing according to any one of claims 5 to 8, wherein the adhesive film comprises an epoxy resin selected from the group consisting of epoxy propylene ether epoxy resin and epoxy propylamine ring. At least one resin selected from the group consisting of an oxyresin, a propylene acrylate epoxy resin, and an alicyclic epoxy resin. The surface protection tape for film polishing according to any one of claims 5 to 9, wherein the adhesive film contains a bisphenol resin. The surface protection tape for film polishing according to claim 10, wherein the bisphenol resin is at least one selected from the group consisting of bisphenol F diglycidyl ether resin and bisphenol A diglycidyl ether resin. 1 species. The surface protection tape for film polishing according to any one of claims 5 to 11, wherein the adhesive film contains an inorganic filler in an amount of less than 60 parts by mass based on 100 parts by mass of the resin component in the adhesive film. . The surface protection tape for film polishing according to any one of claims 5 to 12, wherein the adhesive film contains a compound having a functional group crosslinked with an isocyanate curing agent or an epoxy curing agent, And shows flux activity.