TWI595071B - Semiconductor wafer surface polishing process surface protection adhesive tape and semiconductor wafer grinding method - Google Patents

Description

Surface protection adhesive tape for inner surface polishing processing of semiconductor wafer and polishing processing method of semiconductor wafer

The present invention relates to a surface protection adhesive tape for inner surface polishing processing of a semiconductor wafer for semiconductor element processing, and more particularly to surface protection adhesion for inner surface polishing processing of a semiconductor wafer when the semiconductor wafer is ground. A method of processing a semiconductor wafer with and using it.

In the processing step of the semiconductor wafer, the inner surface polishing and polishing are used to form a pattern on the surface of the semiconductor wafer to make the inner surface of the semiconductor wafer a specific thickness. In this case, in order to protect the surface of the semiconductor wafer from stress during polishing or the like, or to facilitate the polishing process, a surface protective adhesive tape for semiconductor processing is bonded to the surface of the semiconductor wafer, and the inner surface of the semiconductor wafer is polished in this state. As the surface protective adhesive tape for semiconductor processing, for example, an adhesive layer containing an acrylic polymer as a main component is provided on a polyolefin base resin film such as an ethylene-vinyl acetate copolymer (see, for example, Patent Document 1).

Usually, after the semiconductor wafer is thinned to a specific thickness by inner surface polishing, a diced-solid wafer in which an adhesive and an adhesive (adhesive for bonding) are laminated on a substrate in advance is bonded to the semiconductor. The inner surface of the wafer (grinding surface), which is fixed to the crystal cutter by a ring frame The disk is wafer-cut by cutting the semiconductor wafer once by using a dicing step which is cut by a dicing blade. Then, a plurality of wafers are laminated, and the wires are connected between the substrate and the wafer, and then sealed with a resin to form a product (for example, refer to Patent Document 2). When the dicing-solid wafer is bonded to the surface of the semiconductor wafer, the surface of the semiconductor wafer is bonded to the working disk in a state in which the surface protective tape for the inner surface of the semiconductor wafer is bonded to the surface of the semiconductor wafer. After the wafer is solidified, the surface protection adhesive tape for polishing the inner surface of the semiconductor wafer is peeled off. Further, in order to adhere the diced-solid wafer to the semiconductor wafer, it is sometimes heated at a higher temperature (about 80 ° C) in the case of bonding the dicing-solid wafer.

Further, the surface protection adhesive tape for polishing the inner surface of the semiconductor wafer bonded to the surface of the semiconductor wafer is usually colored in order to be recognized and bonded. As a method of coloring, there are a method of coloring a substrate film and a method of coloring an adhesive, but in terms of surface contamination of a semiconductor wafer, generally, a substrate film that does not directly contact the semiconductor wafer is used. Coloring.

With the advancement of high-density packaging technology in recent years, it is necessary to miniaturize semiconductor wafers and significantly thin the semiconductor wafer. Depending on the type of semiconductor wafer, it must be made thin to about 100 μm. Further, there is a tendency that the diameter of the semiconductor wafer is also increased in diameter in order to increase the number of semiconductor wafers that can be manufactured by one-time processing. Semiconductor wafers having a diameter of 5 吋 or 6 迄今为止 have been the mainstream, and in recent years, semiconductor wafers having a diameter of 8 to 12 Å have been processed into semiconductor wafers. By increasing the diameter of the semiconductor wafer, the yield of the primary processing is increased, and the manufacturing cost is reduced.

As the diameter of such a semiconductor wafer is increased, the shape of the semiconductor wafer is constantly changing. In the case of semiconductor wafers with a diameter of 5 吋 or 6 为, in the mainstream The conductor wafer 8 has a large notch 7 called an orientation flat (refer to FIG. 3 described below). In contrast, in order to further improve the yield, the semiconductor wafer 5 having a diameter of 8 Å or more has a notch. (refer to Figure 2 below), the small gap 6 becomes the mainstream. However, with such changes, the reading of semiconductor wafer positions that have hitherto been easy has become difficult. Further, in the semiconductor wafer having the orientation flat, the surface protection adhesive tape for the inner surface of the semiconductor wafer is not bonded to the outer side of the orientation flat surface 7. On the other hand, the semiconductor wafer having the recess is covered with the concave surface. The surface 6 is attached to the surface protection tape for the inner surface of the semiconductor wafer. Therefore, the color of the surface protection tape for the inner surface of the semiconductor wafer has a serious influence on the sensor visibility.

As described above, in order to improve the sensor visibility, it is necessary to adjust the color tone and the like. However, the thinning of semiconductor wafers creates more problems. With the thinning of the semiconductor wafer, the warpage of the semiconductor wafer becomes large, and there is a case where the notch cannot pass through the sensor portion due to warpage, and the sensor cannot be recognized. Further, problems such as the adhesion of dust to the surface of the substrate and the inability to detect the notch are also caused.

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2000-8010

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2007-53325

The present invention is directed to solving the problems unique to semiconductor wafers having recesses as described above.

In particular, the present invention solves the above problems, and aims to provide a semiconductor wafer A surface-protecting adhesive tape for surface polishing processing and a semiconductor wafer polishing method using the same, which is applied to a semiconductor wafer requiring thin film polishing in an inner surface polishing process such as a germanium wafer Produces sensor identification problems, and combines visibility and heat resistance for excellent workability

The present inventors have made an effort to study the above problems, and as a result, it has been found that the roughness of the back surface of the belt is set to a specific range, and the total light transmittance of the belt at a specific wavelength is set to a specific range. The above problems have a conformable visibility and do not cause a sensor identification error, which improves workability.

Here, although the roughness of the back surface of the belt has various surface roughnesses (for example, the center line average roughness Ra), the above-described problem of the present invention can be solved by using the surface roughness defined by Rz.

That is, the subject of the present invention is achieved by the following means.

[1] A surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer, wherein the substrate is provided with an adhesive layer on one side of the substrate, and the adhesive is not formed on the substrate. The surface roughness of the surface of the layer is Rz=0.7~5.0μm, and the surface protection adhesive tape for the inner surface of the semiconductor wafer has a total light transmittance of 40-80% at a wavelength of 500-600 nm, and the color difference of the mirror wafer (ΔEM) and the difference in chromatic aberration (ΔET) in a state in which the surface protective adhesive tape for polishing the inner surface of the semiconductor wafer is bonded to the mirror wafer is ΔET-ΔEM>6.5, and the surface protection is Adhesive tape is used to adhere to the surface of a semiconductor wafer having a recess The step of grinding the inner surface of the semiconductor wafer.

[2] The surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to [1], wherein the surface roughness Rz is 0.7 μm or more and less than 5.0 μm.

[3] The surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to [1] or [2], wherein the substrate contains a pigment selected from the group consisting of an anthraquinone pigment and a naphthalocyanine pigment. , pigments of indanthrone pigments, indanthrene pigments and triaryl carbocation pigments.

[4] The surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to any one of [1] to [3] wherein the substrate has a thickness of 80 to 200 μm.

[5] The surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to any one of [1] to [4] wherein the substrate is composed of a resin composed of the same copolymerization component, The copolymerization component contains at least vinyl acetate.

[6] The surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to [5], wherein the content of the vinyl acetate component is 1.9 to 10.5% by mass.

[7] The surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to any one of [1] to [6] wherein the substrate is a single layer or a plurality of layers, and the substrate does not form an adhesive. The base resin of the outermost layer on the side of the layer has a melting point of 85 ° C or higher.

[8] A method for polishing a semiconductor wafer, wherein a surface of a semiconductor wafer is bonded to a surface of a semiconductor wafer having a notch, and a surface protective tape for polishing the inner surface of the semiconductor wafer is bonded to the inner surface of the semiconductor wafer. The surface protection adhesive tape substrate for polishing the inner surface of the semiconductor wafer and the surface of one side of the substrate are provided with an adhesive layer, and the surface of the substrate on which the adhesive layer is not formed is formed. The roughness is Rz=0.7~5.0μm, The surface protection adhesive tape for the inner surface polishing of the semiconductor wafer has a total light transmittance of 40 to 80% at a wavelength of 500 to 600 nm, a color difference (ΔEM) of the mirror wafer, and a grinding process of the inner surface of the semiconductor wafer. The difference in chromatic aberration (ΔET) in the state in which the surface protective adhesive tape is attached to the mirror wafer is ΔET-ΔEM>6.5.

[9] The method of polishing a semiconductor wafer according to [8], wherein the surface roughness Rz is 0.7 μm or more and less than 5.0 μm.

The surface protective adhesive tape for inner surface polishing processing of the semiconductor wafer of the present invention (hereinafter also referred to as a surface protective adhesive tape) has a conformable visibility in processing of a semiconductor wafer such as an inner surface polishing process of a silicon wafer, and The wafer having the notch also has sensor identification and excellent heat resistance.

Therefore, by using the surface protective adhesive tape for the inner surface polishing processing of the semiconductor wafer of the present invention, the efficiency of the inner surface polishing processing of the semiconductor wafer can be improved, and the workability can be improved.

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

1‧‧‧Substrate (substrate film)

11‧‧‧The surface of the substrate where the adhesive layer is not formed (back)

2‧‧‧Adhesive layer

3‧‧‧ Surface protection adhesive tape for inner surface polishing of semiconductor wafers

4‧‧‧Release liner

5‧‧‧Semiconductor wafer (矽mirror wafer)

6‧‧‧ Notch

7‧‧‧ Orientation plane

8‧‧‧Semiconductor wafer (矽mirror wafer)

Fig. 1 is a cross-sectional view showing an embodiment of a surface protective tape for polishing an inner surface of a semiconductor wafer of the present invention.

2 is a plan view showing an example of a semiconductor wafer 5 having a notch 6 as a sensor identification portion.

3 is a plan view showing an example of a semiconductor wafer 8 having an orientation flat 7 as a sensor identification portion.

Hereinafter, the surface protection adhesive tape for inner surface polishing processing of the semiconductor wafer of the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto.

As shown in Fig. 1, the surface protective adhesive tape 3 for inner surface polishing of a semiconductor wafer of the present invention comprises a substrate 1 and an adhesive layer 2 provided on at least one side of the substrate. Further, in the substrate 1, the surface opposite to the surface contacting the adhesive layer 2 is the surface (back surface) 11 on which the adhesive layer is not formed, and is bonded to the semiconductor wafer 4. The outermost surface of the surface.

The surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer is used in the step of bonding the semiconductor wafer 5 having the recess 6 shown in FIG. 2 to the side on which the integrated circuit is incorporated or formed. In the state of the surface (surface) on the side of the electrode, the side (the inner surface) of the side of the semiconductor wafer 5 on which the integrated circuit is not formed or the side on which the electrode is not formed is polished.

Here, the surface protective adhesive tape 3 for the inner surface polishing processing of the semiconductor wafer of the present invention may be previously cut into a specific shape (pre-cut) in a manner in which the substrate 1 and the adhesive layer 2 are used in combination with each other. It is also possible to take the uncut long strip into a roll shape. The specific shape may be, for example, a circular shape that is the same as the diameter of the semiconductor wafer 5 and covers the portion of the recess 6. As long as the integrated circuit of the semiconductor wafer is protected, the inner surface of the semiconductor wafer can be polished. It may be of any shape without impairing the effects of the present invention.

Further, unless otherwise stated, the numerical range indicated by "~" includes the values before and after.

(substrate)

The main purpose of the substrate 1 (hereinafter also referred to as a substrate film) used in the present invention is to protect the semiconductor wafer from the impact on the inner surface of the semiconductor wafer, and it is particularly important to have a water wash or the like. Water resistance and retention of machined parts. As such a substrate 1, for example, those described in JP-A-2004-186429 can be cited.

Further, as the resin of the substrate 1 used in the present invention, those using the adhesive tape can be usually used. For example, a homopolymer or a copolymer of an α-olefin such as polyethylene, polypropylene, an ethylene-propylene copolymer, a polybutene, an ethylene-vinyl acetate copolymer, an ethylene-acrylate copolymer, or an ionic polymer, A thermoplastic elastomer such as polyethylene terephthalate, polycarbonate, polymethyl methacrylate or the like, a polyurethane, a styrene-ethylene-butylene or a pentene copolymer.

The base material 1 may be a resin selected from the group consisting of a single layer or a plurality of layers, or a mixture of two or more selected from the group may be used in the form of a single layer or a plurality of layers.

The surface (back surface) 11 of the substrate 1 used in the present invention in which the adhesive layer 2 is not formed has a surface roughness of Rz = 0.7 to 5.0 μm. When Rz is less than 0.7 μm, blocking occurs during the application of the adhesive or the film formation of the substrate 1, and thus problems such as inability to manufacture occur. On the other hand, if Rz exceeds 5.0 μm, dust during polishing adheres to the back surface 11 of the belt, and the sensor cannot be recognized. The roughness Rz of the back surface 11 of the substrate is preferably 1.0 μm or more and less than 5.0, more preferably 1.0 to 4.9 μm, still more preferably 1.0 to 4.5 μm, still more preferably 1.0 to 3.5 μm, and most preferably 1.0 to 2.0. Mm.

Further, for example, by controlling the roughness of the cooling roll used when forming the substrate 1 , the roughness of the back surface 11 of the substrate can be set to an arbitrary value. The resin which is fluidized by heating is extruded, and then cooled by a cooling roll to be thinned. Most of the cooling of the resin uses metal rolls or Rubber roller. For example, when a rubber roller is used, the ruthenium particles are mixed into the rubber in order to impart releasability, and the particle diameter of the ruthenium particles is arbitrarily adjusted, whereby the roughness of the back surface 11 of the substrate can be adjusted.

As described above, when the roughness is controlled by the cooling roll, the surface roughness can be uniformly imparted to the entire surface of the substrate 1 where the adhesive layer 2 is not formed.

Further, the melting point of the base resin of the outermost layer on the side where the base material 1 is not formed with the adhesive layer 2 is preferably 85 ° C or higher, and more preferably 95 ° C or higher from the viewpoint of fusion of the working disk. Further, it is preferably 100 ° C or higher, and particularly preferably 110 ° C or higher. Further, the upper limit of the melting point is not particularly limited, and is actually 200 ° C or lower, more preferably 180 ° C or lower.

Here, the substrate on which the outermost layer on the side of the adhesive layer 2 is not formed means a single layer when the substrate 1 is a single layer, and is located at a distance from the adhesive layer 2 when the substrate 1 is a plurality of layers. The substrate layer at the farthest position.

The substrate 1 used in the present invention can preferably use a resin in which the copolymer component contains at least vinyl acetate. Further, the content of the vinyl acetate component is preferably from 1.9 to 10.5% by mass. The copolymerization component to be combined with vinyl acetate may, for example, be an olefin such as ethylene. Further, it may be a binary copolymer or a copolymer of three or more.

Further, in the present invention, the resin composed of the copolymer may be any of a random copolymer, a block copolymer, an alternating copolymer, and a graft copolymer.

In the present invention, an ethylene-vinyl acetate copolymer (hereinafter also referred to as EVA) is particularly preferred.

The resin of the substrate 1 may be composed of a resin composed of the same copolymerization component, or may be laminated by a plurality of resins composed of different copolymerization components, or may be used by mixing a plurality of resins. In the present invention, in consideration of the influence on warpage, the substrate 1 composed of a resin composed of the same copolymerization component is preferred.

In order to identify and identify the surface protective adhesive tape for the inner surface of the semiconductor wafer, the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer is blended with a pigment for coloring (hereinafter also referred to as a pigment). Coloring can also be carried out by adding a pigment or a dye to the adhesive, preferably by adding a pigment to the substrate 1.

The pigment is preferably a blue pigment, and examples thereof include an anthraquinone pigment, a naphthophthalocyanine pigment, an anthraquinone pigment, an indanthrene pigment, and a triarylcarbionic pigment. Among these, an anthraquinone pigment, a naphthophthalocyanine pigment, and more preferably an anthraquinone pigment are preferable, and among them, copper indigo blue is preferable.

The blending amount of the pigment for coloring is preferably 0.005 to 1.0 part by mass, more preferably 0.01 to 0.5 part by mass, per 100 parts by mass of the resin forming the substrate 1. Further, it is more preferable to form a film by multilayer extrusion even if it is the same resin, and to blend the pigment only on the side where the pressure-sensitive adhesive layer is formed. By blending the pigment only on the side where the adhesive layer is formed, even if the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer is immersed in an etching solution such as an acid, it is not exposed to the acid. Therefore, it is possible to prevent discoloration of the surface protective adhesive tape 3 for the inner surface of the semiconductor wafer.

In the case where the substrate 1 is laminated with a plurality of resins composed of different copolymerization components, a resin other than the resin containing at least vinyl acetate in the copolymerization component may be used, and for example, high-density polyethylene may be mentioned (hereinafter also a polyethylene resin such as HDPE), low density polyethylene (hereinafter also referred to as LDPE), a polyolefin resin such as polypropylene, an ethylene-acrylic acid copolymer or an ethylene-methacrylic acid copolymer, and a metal crosslinked body thereof Polyolefins such as ionic polymers).

In the present invention, among these, high density polyethylene, low density polyethylene, and polypropylene are preferred.

In the case where a substrate 1 having a plurality of resins is laminated, in the present invention, a layer containing a resin containing vinyl acetate is preferably provided on the side where the adhesive layer is formed.

Surface protection adhesive tape for inner surface polishing processing of semiconductor wafer of the present invention The substrate 1 used has a melt flow rate (MFR: Melt flow rate) measured based on JIS K 7210 of preferably 1.0 to 2.9 g/10 min, more preferably 1.5 to 2.5 g/10 min, and further preferably It is 1.8~2.3g/10 minutes.

When the MFR of the substrate 1 is in the above range, the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer wound in a roll shape is placed on the bonding machine to wind up the inner surface of the semiconductor wafer. The surface of the semiconductor wafer 5 is adhered to the surface of the semiconductor wafer 5 by the surface of the semiconductor wafer 5, and the dicing blade heated to about 150 ° C is rotated along the outer periphery of the semiconductor wafer 5 to be inside the semiconductor wafer. The surface-protecting adhesive tape 3 for surface polishing is cut into a semiconductor wafer shape, and the semiconductor wafer 5 is covered with the substrate 1 of the surface-protecting adhesive tape 3 for polishing the inner surface of the semiconductor wafer by the heat generated at this time. Fusion is performed in a side manner. As a result, the interface between the adhesive layer 2 and the semiconductor wafer 5 is covered with the substrate 1, so that seepage can be prevented.

In other words, when the MFR exceeds 2.9 g/10 minutes, since the fluidity of the substrate 1 becomes high, a certain point on the outer circumference of the dicing blade and the semiconductor wafer 5 when the substrate 1 after melting is cut is cut. Since the contact time is very short, once the resin constituting the substrate 1 is sharply cut, the fusion of the side surface of the semiconductor wafer 5 is not performed. On the other hand, when it is less than 1.0 g/10 minutes, the fluidity of the base material 1 becomes low, and the interface of the semiconductor wafer 5 cannot be covered by the tape.

In order to set the MFR of the substrate 1 to the above range, for example, it is possible to adjust the copolymerization target of the resin, the vinyl acetate content, the molecular weight, or the distribution thereof, to mix the resins having different MFRs, or to combine the methods. .

The resin of the substrate 1 used in the present invention may optionally contain a stabilizer, a lubricant, an antioxidant, an anti-caking agent, a plasticizer, an adhesion-imparting agent, a soft material, and the like.

The thickness of the substrate 1 is not particularly limited and may be appropriately set, and is preferably 80 to 200 μm, more preferably 100 to 180 μm.

By setting the thickness to this range, it is excellent in the property of the surface protection adhesive tape 3 for polishing the inner surface of the semiconductor wafer, and the workability at the time of processing is improved. Further, if the thickness is excessively increased, there is an influence on the productivity of the substrate 1, resulting in an increase in manufacturing cost.

The method for producing the substrate 1 is not particularly limited, and can be produced by a conventional extrusion or extrusion technique such as a calendering method, a T-die extrusion method, an inflation method, or a casting method, and the productivity and the obtained substrate can be considered. The thickness accuracy of 1 is appropriately selected.

(adhesive layer)

The material of the adhesive used for the surface protection adhesive tape 3 for the inner surface polishing processing of the semiconductor wafer of the present invention is not particularly limited, and the former can be used. For example, it may have a property that it is hardened by irradiation with radiation and the adhesiveness is lowered to be easily peeled off from the semiconductor wafer 5. Specific examples thereof include a homopolymer having a (meth) acrylate as a constituent component, a copolymer having a (meth) acrylate as a constituent component, a (meth)acrylic resin, and a (meth) acrylate.

The mass average molecular weight of the resins is preferably from 200,000 to 2,000,000, more preferably from 300,000 to 1.5 million, and further preferably from 400,000 to 1.2 million.

Further, the mass average molecular weight was measured by a gel permeation chromatography (manufactured by Waters, trade name: 150-C ALC/GPC) for a 1% solution obtained by dissolving in tetrahydrofuran, and the measured value was taken as Calculated by mass average molecular weight in terms of polystyrene.

Examples of the monomer component of the polymer containing (meth) acrylate as a constituent component include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, and isobutyl group. , pentyl, isopentyl, hexyl, heptyl, cyclohexyl, 2-ethylhexyl, octyl, isooctyl, Sulfhydryl, isodecyl, fluorenyl, isodecyl, undecyl, lauryl, thirteenyl, tetradecyl, stearyl, stearyl and dodecyl have carbon numbers below 30, Preferred are alkyl (meth) acrylate or alkyl (meth) methacrylate having a linear or branched alkyl group of 4 to 18 carbon atoms. These may be used alone or in combination of two or more.

The constituent components in the (meth) acrylate resin other than the above may include the following monomers. Examples thereof include acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Carboxyl monomer; anhydride monomer such as maleic anhydride or itaconic anhydride; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate , 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, and (meth)acrylic acid a hydroxyl group-containing monomer such as (4-hydroxymethylcyclohexyl)methyl ester; styrenesulfonic acid, allylsulfonic acid, 2-(methyl)propenylamine-2-methylpropanesulfonic acid, (methyl) a sulfonic acid group-containing monomer such as acrylamide propyl sulfonic acid, sulfopropyl (meth) acrylate, or (meth) propylene phthaloxy naphthalene sulfonic acid; (Meth) acrylamide, N-hydroxymethyl decyl (meth) acrylate, alkyl amino alkyl (meth) acrylate (eg dimethylaminoethyl methacrylate, methacrylic acid) Tributylaminoethyl ester, etc.), N-ethylene Pyrrolidone, propylene hydrazine, vinyl acetate, styrene, acrylonitrile. These monomer components may be used alone or in combination of two or more.

Further, the (meth) acrylate resin may contain the following polyfunctional monomer as a constituent component. For example, hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) Acrylate, neopentyl alcohol di(meth) acrylate, trimethylolpropane tri(meth) acrylate, tetramethylol methane four (Meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta(meth)acrylate, dipentaerythritol Alcohol hexa (meth) acrylate, epoxy (meth) acrylate, polyester (meth) acrylate and urethane (meth) acrylate. These may be used alone or in combination of two or more.

Examples of the acrylate include ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, glycidyl acrylate, and 2-hydroxyethyl acrylate. Further, a methacrylic polymer such as a methacrylate substituted with the above acrylate may be used, and a curing agent may be used.

As the curing agent, a curing agent described in JP-A-2007-146104 can be used. For example, 1,3-bis(N,N-diepoxypropylaminomethyl)cyclohexane, 1,3-bis(N,N-diepoxypropylaminomethyl)toluene, 1,3-bis(N,N-diepoxypropylaminomethyl)benzene, N,N,N',N'-tetraepoxypropyl m-decanediamine has two or more epoxys in the molecule Epoxy compound; toluene diisocyanate (TDI) such as 2,4-toluene diisocyanate or 2,6-toluene diisocyanate; 1,3-deanyl diisocyanate; 1,4-decyl diisocyanate An isocyanate compound having two or more isocyanate groups in a molecule such as diphenylmethane diisocyanate (MDI) such as mercapto diisocyanate (XDI) or diphenylmethane-4,4'-diisocyanate or trimethylol group of TDI a prepolymer of such isocyanate compounds such as a propane adduct; tetramethylol-tris(β-aziridine)propionate, trimethylol-tris(β-aziridine)propionate , such as trimethylolpropane-tris(β-aziridine)propionate, trimethylolpropane-tris[β-(2-methylaziridine)]propionate, etc. The above aziridine-based aziridine-based compound.

The content of the curing agent may be adjusted according to the desired adhesive strength, and is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the resin component.

Moreover, by including a photopolymerizable compound and a photopolymerization initiator in the adhesive layer 2, it can be cured by irradiation with ultraviolet rays, whereby the adhesive force of the adhesive can be reduced. In the above-mentioned photopolymerizable compound, for example, it is widely used in the molecule obtained by stereoscopically rectifying by light irradiation as described in JP-A-60-196956 and JP-A-60-223139. A low molecular weight compound of two or more photopolymerizable carbon-carbon double bonds.

Specifically, trimethylolpropane triacrylate, neopentyl alcohol triacrylate, neopentyl alcohol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate can be used. Or 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, commercially available oligoester acrylate, and the like.

As the photopolymerization initiator, a photopolymerization initiator described in JP-A-2007-146104 or JP-A-2004-186429 can be used. Specifically, isopropyl benzoin ether, isobutyl benzoin ether, benzophenone, mischrone, and chloro 9-oxosulfide can be used. , benzyl methyl ketal, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethyl phenyl propane, and the like. These may be used alone or in combination of two or more. The amount of the photopolymerization initiator to be added is preferably 0.1 to 15 parts by mass, more preferably 5 to 10 parts by mass, per 100 parts by mass of the resin component.

In addition, as the adhesive layer 2, a photopolymerizable adhesive layer obtained by using a resin composition containing a polymer having a photopolymerizable carbon-carbon double bond in a polymer, a photopolymerization initiator, and a curing agent can be used. The polymer having a carbon-carbon double bond in the polymer is preferably a (meth) acrylate having an alkyl group having a carbon number of 4 to 12 (more preferably 8 carbon atoms) in a side chain by any method. A (meth)acrylic polymer obtained by homopolymerization or copolymerization of one or more of a monomer or a copolymerizable modifying monomer.

The photopolymerizable adhesive layer formed in the above manner is inside the semiconductor wafer Before the surface protective adhesive tape 3 for surface polishing is peeled off from the surface of the semiconductor wafer 5, the adhesion of the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer to the surface of the semiconductor wafer 5 is irradiated from the substrate 1 side. The reduced radiation is preferably ultraviolet light, whereby the adhesive force is greatly reduced from the initial adhesion, and the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer can be easily peeled off from the adherend.

Further, as the adhesive, an adhesion-imparting agent, an adhesive adjustment agent, a surfactant, an inorganic compound filler, and other modifiers may be blended as needed.

In the present invention, the thickness of the adhesive layer 2 can be appropriately set depending on the adherend to be applied, and is not particularly limited, and is preferably 10 to 60 μm, more preferably 20 to 50 μm. Further, the adhesive layer 2 may have a structure in which a plurality of layers are laminated.

By adjusting the thickness of the adhesive layer 2 to the above range, productivity is excellent and manufacturing cost is lowered. Further, since the adhesive force of the adhesive layer 2 is not excessively increased, when the adhesive layer 2 is peeled off after the inner surface polishing, there is no damage of the semiconductor wafer 5 due to an increase in the peeling adhesion force or the semiconductor wafer. The surface of 5 is contaminated by the adhesive layer 2.

Moreover, the adhesion of the unevenness on the surface of the semiconductor wafer 5 is excellent, and when the inner surface of the semiconductor wafer 5 is polished, chemically treated, or the like, water or chemical liquid does not permeate, and the semiconductor wafer 5 is broken or The polishing chips on the surface of the semiconductor wafer 5 or the contamination caused by the chemical liquid are sufficiently reduced in adhesion after the radiation irradiation, and the semiconductor wafer 5 is not damaged when the adhesive layer 2 is peeled off from the semiconductor wafer 5.

In the present invention, when the adhesive layer 2 is provided on one side of the substrate 1, the above-mentioned adhesive can be used by a roll coater, a notch coater, a die coater, and a Meyer bar. Paint A method of forming and drying the adhesive layer 2 by a known method such as a cloth machine, a reverse roll coater, or a gravure coater. At this time, in order to protect the applied adhesive layer 2 from environmental pollution or the like, it is preferable to apply a release liner 4 (also referred to as a release film) to the surface of the applied adhesive layer 2.

The release film used for the surface protection adhesive tape 3 for the inner surface polishing processing of the semiconductor wafer of the present invention may, for example, be a synthetic resin such as polypropylene or polyethylene terephthalate. It is preferred to carry out an anthrone treatment or the like on the surface as needed. The thickness of the release film is usually 10 to 100 μm, preferably 20 to 50 μm.

By adopting this configuration, it is possible to obtain a surface protective adhesive tape 3 for polishing the inner surface of a semiconductor wafer which maintains excellent adhesion to the surface of the semiconductor wafer and excellent peelability at the time of peeling and which also has low contamination. That is, by forming the adhesive layer 2 on one side of the substrate 1, even when irregularities are present on the surface of the semiconductor wafer, good adhesion to the surface of the semiconductor wafer can be obtained, and the semiconductor wafer can be obtained. When the inner surface is subjected to polishing processing, chemical liquid treatment, or the like, penetration of polishing water, chemical liquid, or the like is prevented, and damage or contamination of the semiconductor wafer due to the semiconductor wafer can be prevented.

Further, when the surface protective adhesive tape 3 for the inner surface polishing is peeled off from the surface of the semiconductor wafer, the adhesive layer 2 is cured and shrunk by irradiation of radiation, whereby the adhesive force of the entire adhesive layer is sufficiently reduced and does not deteriorate. The semiconductor wafer can be used to peel off the surface protection adhesive tape 3 for the inner surface of the semiconductor wafer with good workability. Therefore, the surface protective adhesive tape 3 for the inner surface polishing processing of the semiconductor wafer of the present invention can achieve low contamination at the same time while maintaining excellent adhesion to the unevenness and easy peeling property at the time of peeling.

The surface protective adhesive tape 3 for the inner surface polishing processing of the semiconductor wafer of the present invention has a total light transmittance of 40 to 80% at a wavelength of 500 to 600 nm. The lower limit of the total light transmittance is preferably It is 50% or more, more preferably more than 50%, further preferably 51% or more, and particularly preferably 53% or more. On the other hand, the upper limit of the total light transmittance is preferably 70% or less.

If the total light transmittance of the wavelength of 500 to 600 nm is less than 40%, the detection of the notch becomes difficult, and the sensor identification may be erroneous. Further, when the total light transmittance of the wavelength of 500 to 600 nm exceeds 80%, since the transparency is high, it is difficult to recognize whether or not the bonding is performed.

In the present invention, the chromatic aberration of the mirror wafer (ΔEM) and the surface protective adhesive tape 3 for the inner surface polishing of the semiconductor wafer of the present invention are attached to the chromatic aberration of the wafer to which the wafer is bonded. The difference of (ΔET) is ΔET-ΔEM>6.5. ΔET-ΔEM is preferably greater than 7.0, more preferably greater than 7.8. If ΔET-ΔEM is 6.5 or less, it is impossible to see at a glance whether or not the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer is bonded to the mirror wafer, so that the inner surface of the semiconductor wafer is polished. The main reason for the error such as double bonding of the surface protection adhesive tape 3 is. Further, the upper limit of ΔET-ΔEM is not particularly limited, and is preferably ΔET-ΔEM<30, more preferably ΔET-ΔEM<25, still more preferably ΔET-ΔEM<20.

The adhesion of the surface protective adhesive tape for the inner surface polishing processing of the semiconductor wafer of the present invention to the SUS plate polished by #280 sandpaper at a normal temperature (25 ° C) is preferably in the case of a pressure sensitive adhesive. 0.3~5.0N/25mm. On the other hand, in the case of the ultraviolet curable adhesive, the adhesive force before ultraviolet curing is preferably 1.0 to 20 N/25 mm, and the adhesion after ultraviolet curing is preferably 0.01 to 1.0 N/25 mm. In the case of the pressure-sensitive adhesive, unlike the ultraviolet-curable adhesive, it is difficult to greatly adjust the adhesive force. Therefore, if it is 5.0 N/25 mm or more, peeling failure or paste residual problem may occur. On the other hand, when it is 0.3 N/25 mm or less, there is a problem that dust intrudes or the tape falls off, and the wafer is broken. In the case of an ultraviolet curing adhesive, the adhesion at the time of peeling can be arbitrarily controlled by ultraviolet irradiation, in the ultraviolet The range of preferred adhesion force before and after hardening of the wire is different.

By adjusting the adhesion to the above range, the surface protection adhesive tape for the inner surface polishing of the semiconductor wafer during the polishing process does not fall off from the semiconductor wafer, thereby improving the percolation or the breakage of the semiconductor wafer. Moreover, peeling after polishing is also easy, thereby improving semiconductor wafer breakage or paste residue.

In addition, the adhesive force which can be reduced by the peeling of a radiation-hardening type adhesive tape, etc. is the adhesive force measured in the state before the grinding|polishing process process, and the state before and after the adhesive-reduction process.

In order to impart such an adhesive force, it is possible to achieve the above-described range by adjusting the amount of the hardener to be blended by a preferred constitution of the above-mentioned adhesive layer.

Further, in addition, the adhesive force of the adhesive may be the same adhesive, and may be adjusted by the thickness of the adhesive layer or the kind of the substrate.

As the size of the notch identifiable by the present invention, for example, the notch depth specified by the SEMI standard and the JEITA specification is 1.00 mm (allowable error + 0.25 mm, -0.00 mm), and the notch angle is 90 (allowable error + 5°, -1°). By using the surface protection adhesive tape for the inner surface polishing processing of the semiconductor wafer of the present invention, a good sensor is used even for a semiconductor wafer having a recess which is more difficult to identify the sensor than the orientation flat. The effect of identification.

As a semiconductor wafer having a notch recognizable by the present invention, a semiconductor wafer having a large diameter such as 8 Å or 12 Å can be cited.

(Method of grinding semiconductor wafers)

The method for grinding a semiconductor wafer of the present invention has the following steps: The surface of the semiconductor wafer is bonded to the surface protection adhesive tape for the inner surface polishing processing of the semiconductor wafer of the present invention.

The surface protective adhesive tape substrate for polishing the inner surface of the semiconductor wafer is provided with an adhesive layer on one side of the substrate, and the surface roughness of the surface of the substrate on which the adhesive layer is not formed is Rz= 0.7~5.0μm, the surface protection adhesive tape for the inner surface of the semiconductor wafer has a total light transmittance of 40-80% at a wavelength of 500-600 nm, the color difference (ΔEM) of the mirror wafer and the semiconductor wafer The difference in chromatic aberration (ΔET) in the state in which the surface protective adhesive tape for the inner surface polishing is bonded to the mirror wafer is ΔET-ΔEM>6.5.

The surface protection adhesive tape for the inner surface polishing processing of the semiconductor wafer of the present invention used in the semiconductor wafer polishing method is applied to the preferred range of the surface protection adhesive tape for the inner surface polishing processing of the semiconductor wafer described above. By.

Hereinafter, the polishing method of the semiconductor wafer of the present invention will be described in more detail, but it is not limited thereto.

First, the release liner 4 is peeled off from the adhesive layer 2 of the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer, and the surface of the adhesive layer 2 is exposed, and is bonded to the concave layer via the adhesive layer 2 The semiconductor wafer of the port is incorporated in the side of the integrated circuit or the side (surface) on the side where the electrode is formed. Then, the semiconductor wafer is fixed to the working disk of the polishing machine or the like through the base material layer 1 of the surface protective adhesive tape 3 for the inner surface polishing processing of the semiconductor wafer, and the semiconductor wafer is not incorporated into the integrated circuit. The side (the inner surface) on the side or the side where the electrode is not formed is subjected to polishing processing, drug treatment, or the like. After the polishing process, the drug treatment, and the like are completed, the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer is peeled off.

Here, the surface protection adhesive tape 3 for the inner surface of the semiconductor wafer is For the bonding operation of the semiconductor wafer, for example, an automatic tape winding device of a bonding machine DR8500III (trade name: manufactured by Nitto Seiki Co., Ltd.) can be used.

For the polishing processing operation of the inner surface of the semiconductor wafer, for example, a device of DGP8760 (trade name: manufactured by Disco Co., Ltd.) can be used.

Further, the peeling timing of the surface protective adhesive tape 3 for polishing the inner surface of the semiconductor wafer is performed by polishing the inner surface of the semiconductor wafer and thinning the film, and then bonding the inner surface of the semiconductor wafer to the substrate. It is carried out by laminating the bonding surface of the dicing-solid wafer (cutting ribbon) of the adhesive and the adhesive, and performing wafer mounting.

In the peeling step of the wafer-bonding of the dicing tape and the surface-protecting adhesive tape 3 for the inner surface polishing of the semiconductor wafer, for example, a device of RAD-2700F (trade name: manufactured by Linde Co., Ltd.) can be used.

When bonding to a diced-solid wafer, the diced-solid wafer is adhered to the semiconductor wafer by heating at a high temperature (about 80 ° C). Since the surface protective adhesive tape 3 for the inner surface polishing processing of the semiconductor wafer of the present invention is excellent in heat resistance, it does not have problems such as melting or deformation even when heated, and functions as a surface protective adhesive tape.

In the method for polishing a semiconductor wafer of the present invention, the surface protection adhesive tape 3 for inner surface polishing of the semiconductor wafer of the present invention which is excellent in sensor visibility and excellent in visibility and heat resistance is used, and Compared with the prior grinding processing method, work efficiency is increased, and workability is further improved.

[Examples]

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

(Example 1)

An ethylene-vinyl acetate copolymer (EVA) resin A having a content of 6.0 parts by mass based on 100 parts by mass of the vinyl acetate component, and 0.6 parts by mass of a blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene-vinyl acetate copolymer (EVA) resin B. The substrate film A having a thickness of 165 μm and a surface roughness Rz of the back surface of 1.2 μm was obtained by extrusion molding using an extrusion molding machine.

The blending is carried out at a ratio of 2 mol% of methacrylic acid, 50 mol% of 2-ethylhexyl acrylate, 30 mol% of 2-hydroxyethyl acrylate, and 18 mol% of methyl acrylate, and 0.2 parts by mass is added to 100 parts by mass of the total monomers. Azobisisobutyronitrile was copolymerized in a reaction vessel purged with nitrogen at a temperature of 70 ° C to obtain a polymer solution having a mass average molecular weight of 800,000. In the polymer solution, 2.0 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 30 μm, and bonded to the base film 1 (in the first embodiment) The film A) was obtained to obtain a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 195 μm.

(Example 2)

Ethylene-vinyl acetate copolymer (EVA) resin A in an amount of 6.0 parts by mass based on 100 parts by mass of the vinyl acetate component, dry blending 0.3 parts by mass of a blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene-vinyl acetate copolymer (EVA) resin B. The base film B having a thickness of 165 μm and a surface roughness Rz of the back surface of 0.7 μm was obtained by extrusion molding using an extrusion molding machine.

The blending was carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of butyl acrylate, and 0.3 parts by mass of azobisisobutyronitrile was added to 100 parts by mass of the total monomers, and nitrogen gas was passed through In the replacement reaction vessel, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 300,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 40 μm, and bonded to the base film 1 (in the second embodiment) The material film B) was obtained to obtain a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 205 μm.

(Example 3)

Ethylene-vinyl acetate copolymer (EVA) resin C in an amount of 10.0% by mass based on 100 parts by mass of the vinyl acetate component, and 0.6 parts by mass of the blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene-vinyl acetate copolymer (EVA) resin B. The base film C having a thickness of 100 μm and a surface roughness Rz of the back surface of 3.7 μm was obtained by extrusion molding using an extrusion molding machine.

The blending is carried out at a ratio of 2 mol% of methacrylic acid, 29 mol% of 2-hydroxyethyl acrylate, and 69 mol% of 2-ethylhexyl acrylate, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomers. In the reaction vessel purged with nitrogen, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 230,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive layer is made to have a thickness of the adhesive layer 2 of 30 μm. The coating composition was applied onto the release liner 4, and bonded to the base film 1 (the base film C in Example 3) to obtain a surface protective adhesive tape 3 for inner surface polishing having a thickness of 130 μm.

(Example 4)

Ethylene-vinyl acetate copolymer (EVA) resin C in an amount of 10.0% by mass based on 100 parts by mass of the vinyl acetate component, dry blending 0.8 parts by mass of a blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene-vinyl acetate copolymer (EVA) resin B. The substrate film D having a thickness of 100 μm and a surface roughness of the back surface of Rz = 4.9 μm was obtained by extrusion molding using an extrusion molding machine.

The blending is carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of 2-ethylhexyl acrylate, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomers. In the reaction vessel purged with nitrogen, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 700,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 30 μm, and bonded to the base film 1 (in the fourth embodiment) The material film D) was obtained to obtain a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 130 μm.

(Example 5)

Ethylene-vinyl acetate copolymer (EVA) resin C in an amount of 10.0% by mass based on 100 parts by mass of the vinyl acetate component, 3.0 parts by mass of the blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene-vinyl acetate copolymer (EVA) resin B. Low density polyethylene (LDPE) and dry blended with the above EVA resin by an extrusion molding machine Extrusion molding was carried out, whereby a base film E having a thickness ratio of LDPE: EVA = 1:1 and a thickness of 80 μm and a surface roughness of the back surface of Rz = 2.1 μm was obtained.

The blending is carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of 2-ethylhexyl acrylate, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomers. In the reaction vessel purged with nitrogen, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 700,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in FIG. 1, the obtained adhesive composition was applied to the release liner 4 so that the thickness of the adhesive layer 2 became 40 μm, and was bonded to the substrate 1 (the substrate in Example 5). On the EVA side of the film E), a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 120 μm was obtained.

(Example 6)

Ethylene-vinyl acetate copolymer (EVA) resin C in an amount of 10.0% by mass based on 100 parts by mass of the vinyl acetate component, 5.0 parts by mass of the blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene-vinyl acetate copolymer (EVA) resin B. The high-density polyethylene (HDPE) and the dry-blended EVA resin are extrusion-molded by an extrusion molding machine, thereby obtaining a thickness ratio of HDPE:EVA=3:7 and a thickness of 200 μm and a surface roughness of the back surface of Rz=3.2. Substrate film F of μm.

The blending is carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of 2-ethylhexyl acrylate, and 0.3 parts by mass of azobisisobutyronitrile is added with respect to 100 parts by mass of the total monomers. In a reaction vessel purged with nitrogen, the temperature is equal to ethyl acetate at 70 ° C Copolymerization was carried out in the solution, whereby a polymer solution having a mass average molecular weight of 700,000 was obtained. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 became 40 μm, and bonded to the base film 1 (in the sixth embodiment) On the EVA side of the material film F), a surface protection adhesive tape 3 for inner surface polishing processing having a thickness of 240 μm was obtained.

(Comparative Example 1)

The blending is carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of 2-ethylhexyl acrylate, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomers. In the reaction vessel purged with nitrogen, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 700,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 42 μm, and bonded to the base film 1 (thickness in Comparative Example 1) Teijin Tetoron Film G2C (trade name, manufactured by Teijin Dupont Films Co., Ltd.) having a surface roughness Rz of 0.1 μm on the back surface of 38 μm was obtained to obtain a surface protection tape 3 for inner surface polishing processing having a thickness of 80 μm.

(Comparative Example 2)

The low-density polyethylene (LDPE) resin was extrusion-molded by an extrusion molding machine, whereby a base film G having a thickness of 150 μm and a surface roughness Rz of the back surface of 5.8 μm was obtained.

1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, 2-ethylhexyl acrylate a ratio of 77 mol% of the ester is blended, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomer, and the solution is equal to the ethyl acetate solution at a temperature of 70 ° C in a reaction vessel substituted with nitrogen. Copolymerization was carried out, whereby a polymer solution having a mass average molecular weight of 700,000 was obtained. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 30 μm, and bonded to the base film 1 (Comparative Example 2) The material film G) was obtained to obtain a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 180 μm.

(Comparative Example 3)

100 parts by mass of a low-density polyethylene (LDPE) resin, dry blended with 30 parts by mass of an ethylene-vinyl acetate copolymer containing a blue pigment copper indigo 5.0% by mass and a vinyl acetate component content of 6.0% by mass ( EVA) Resin B. The dry-blended resin was subjected to extrusion molding by an extrusion molding machine, whereby a base film H having a thickness of 300 μm and a surface roughness Rz of the back surface of 2.5 μm was obtained.

The blending is carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of 2-ethylhexyl acrylate, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomers. In the reaction vessel purged with nitrogen, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 700,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 30 μm, and bonded to the base film 1 (Comparative Example 3) The material film H) was obtained to obtain a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 330 μm.

(Comparative Example 4)

Ethylene-vinyl acetate copolymer (EVA) resin C in an amount of 10.0% by mass based on 100 parts by mass of the vinyl acetate component, and 4.0 parts by mass of the blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene-vinyl acetate copolymer (EVA) resin B. The low-density polyethylene (LDPE) and the dry-blended EVA resin were extrusion-molded by an extrusion molding machine, thereby obtaining a thickness ratio of LDPE: EVA = 3:7 to a thickness of 100 μm and a back surface roughness of Rz = 7.1. Substrate film I of μm.

The blending is carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of 2-ethylhexyl acrylate, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomers. In the reaction vessel purged with nitrogen, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 700,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 30 μm, and bonded to the base film 1 (Comparative Example 4 On the EVA side of the material film I), a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 130 μm was obtained.

(Comparative Example 5)

Ethylene-vinyl acetate copolymer (EVA) resin D in an amount of 20.0% by mass based on 100 parts by mass of the vinyl acetate component, dry blending 0.3 parts by mass of a blue pigment copper indigo blue 5.0% by mass and vinyl acetate The content of the component was 6.0% by mass of ethylene vinyl acetate copolymer (EVA) resin B. The substrate film J having a thickness of 165 μm and a surface roughness Rz of the back surface of 6.8 μm was obtained by extrusion molding using an extrusion molding machine.

The blending is carried out at a ratio of 1 mol% of methacrylic acid, 22 mol% of 2-hydroxyethyl acrylate, and 77 mol% of 2-ethylhexyl acrylate, and 0.2 parts by mass of azobisisobutyronitrile is added to 100 parts by mass of the total monomers. In the reaction vessel purged with nitrogen, the copolymerization was carried out at a temperature of 70 ° C in an ethyl acetate solution to obtain a polymer solution having a mass average molecular weight of 700,000. In the polymer solution, 1.5 parts by mass of Coronate L (trade name, manufactured by Nippon Polyurethane Industry Co., Ltd.) which is a hardener was blended with respect to 100 parts by mass of the polymer to obtain an adhesive composition.

As shown in Fig. 1, the obtained adhesive composition was applied onto the release liner 4 so that the thickness of the adhesive layer 2 was 30 μm, and bonded to the base film 1 (Comparative Example 5) The film J) was obtained to obtain a surface protective adhesive tape 3 for inner surface polishing processing having a thickness of 195 μm.

Further, the mass average molecular weight of the resin is measured by a gel permeation chromatography (manufactured by Waters, trade name: 150-C ALC/GPC) for a 1% solution obtained by dissolving in tetrahydrofuran, and will be measured. The value is calculated as the mass average molecular weight in terms of polystyrene.

(Performance evaluation of surface protection adhesive tape for inner surface polishing of semiconductor wafers)

The surface protective adhesive tape 3 for the inner surface polishing processing of each of the semiconductor wafers obtained in the above Examples 1 to 6 and Comparative Examples 1 to 5 was subjected to the following test, and the performance was evaluated to obtain the results shown in Tables 1 and 2 below. .

(Measurement of surface roughness of the back surface of the substrate film)

The surface roughness Rz of the back surface of the base film is based on JIS B0601, and the center of the base film 1 having a width of 230 mm is observed in the width direction and the position of 80 mm from the center is about 3 mm, and "Handisurf E-30A" is used. (product name: manufactured by Tokyo Precision Co., Ltd.) The measurement was performed in two directions of the longitudinal direction and the width direction of the length of 5 mm, and the value obtained by obtaining the ten-point average roughness Rz was obtained.

(Total light transmittance measurement)

The release liner 4 was peeled off from the surface protection adhesive tape 3 for polishing the inner surface of the semiconductor wafer of the example and the comparative example, and a spectrophotometer UV3101PC & MPC-3100 (trade name, manufactured by Shimadzu Corporation) was used for N=3. The total light transmittance at a wavelength of 500 to 600 nm from the surface side of the base film 1 was measured, and the average value was determined.

(evaluation of visibility)

The release liner 4 was peeled off from the surface protection adhesive tape 3 for polishing the inner surface of the semiconductor wafer of the example and the comparative example, and a color difference meter CR-400 (trade name, manufactured by Konica Minolta Co., Ltd.) was used. The color difference was measured. The color difference (ΔEM) of the mirror wafer based on the white color was measured using a white calibration plate. The surface protection adhesive tape 3 for the inner surface polishing processing after the surface protection adhesive tape 3 for polishing the inner surface of each semiconductor wafer of the embodiment and the comparative example is peeled off without the air entering. The mirror wafer was measured to determine the color difference (ΔET) of the bonded wafer. The difference (ΔET - ΔEM) between the color difference (ΔET) of the wafer to which the tape was attached and the color difference (ΔEM) of the mirror wafer was calculated and evaluated using the following criteria.

A: △ ET - △ EM > 6.5

C: △ ET - △ EM ≦ 6.5

(sensor identification evaluation)

The surface protective tape 3 for polishing the inner surface of each of the semiconductor wafers of the examples and the comparative examples in which the release liner 4 was peeled off was bonded to each other by using a bonding machine DR8500III (trade name: manufactured by Nitto Seiki Co., Ltd.). 8 吋矽 mirror wafer with notch 6 as shown in Figure 2 (Shin-Etsu Semiconductor A semiconductor wafer manufactured by an industrial company with a notch depth of 1.00 mm (allowable error + 0.25 mm, -0.00 mm) and a notch angle of 90 (permissible error + 5 °, -1 °).

Then, the surface of the surface-protective pressure-sensitive adhesive tape 3 for polishing the inner surface of the unbonded semiconductor wafer of the above-mentioned semiconductor wafer was polished to a thickness of 100 μm using DGP8760 (trade name: manufactured by Disco Co., Ltd.). The RAD-2700F (trade name: manufactured by Linde Co., Ltd.) is used to perform wafer bonding on the diced tape on the polished semiconductor wafer and stripping of the surface protection tape 3 for polishing the inner surface of the semiconductor wafer. And use the following benchmarks for evaluation.

A: Can be smoothly stripped

C: The detection error of the notch occurs when the tape is bonded

(evaluation of warpage)

The surface protective adhesive tape 3 for polishing the inner surface of each semiconductor wafer of the embodiment and the comparative example in which the release liner 4 is peeled off is bonded to the same concave shape as described above in the same manner as the above-described sensor identification evaluation. 8 吋矽 mirror wafers (semiconductor wafers) of the mouth 6 using a grinder DGP8760 (manufactured by Di Cisco Co., Ltd.) with an in-line mechanism, respectively, and 25 pieces of the bonded semiconductor wafers The surface of the surface-protecting adhesive tape 3 for the inner surface polishing processing of the unbonded semiconductor wafer was polished to a thickness of 50 μm, and evaluated by the following criteria.

A: The warpage of 25 semiconductor wafers is less than 10mm.

B: at least one of the semiconductor wafers has a warpage of 10 mm or more and less than 20 mm.

C: at least one of the semiconductor wafers has a warpage of 20 mm or more.

(Evaluation of heat resistance)

The surface protection adhesive tape 3 for polishing the inner surface of each of the semiconductor wafers of the embodiment and the comparative example in which the release liner 4 is peeled off is bonded to and in the same manner as the above-described sensor identification evaluation. The same 吋矽 mirror wafer (semiconductor wafer) having the notch 6 is described so that the surface of the surface protection adhesive tape for polishing the inner surface of the semiconductor wafer contacts the heating plate to bond the semiconductors The wafer was placed on a hot plate at 80 ° C and placed for 3 minutes. Then, the back surface (base material film side) of the surface protective adhesive tape for polishing the inner surface of the semiconductor wafer was visually observed and evaluated by the following criteria.

A: No melting or the like was observed, and there was no change before and after heating.

C: It was found that the back side melted due to heating, etc.

As shown in Tables 1 and 2, in Examples 1 to 6, there was no problem in visibility (adhesion recognition), and the semiconductor wafer in which the sensor was identified as error-free and polished into a film was adhered to the crystal. The tape can peel off the surface protective adhesive tape for polishing the inner surface of the semiconductor wafer, and is excellent in heat resistance. On the other hand, in Comparative Example 1, it was not possible to see at a glance whether or not the surface protective adhesive tape for the inner surface polishing of the semiconductor wafer was bonded, and there was a problem in visibility. Further, in Comparative Examples 2, 4, and 5, since the surface roughness (Rz) of the back surface of the substrate was large, a large amount of dust adhered to the film polishing of the semiconductor wafer, and an error in which the notch could not be detected occurred. Further, in Comparative Example 3, the color was dark and the total light transmittance was poor, so that an error in which the notch could not be detected occurred.

1‧‧‧Substrate (substrate film)

2‧‧‧Adhesive layer

3‧‧‧ Surface protection adhesive tape for inner surface polishing of semiconductor wafers

4‧‧‧Release liner

11‧‧‧The surface of the substrate where the adhesive layer is not formed (back)

Claims (9)

A surface protection adhesive tape for inner surface polishing processing of a semiconductor wafer, wherein the substrate is provided with an adhesive layer on one side of the substrate, and the surface of the substrate is not formed with an adhesive layer The surface roughness is Rz=0.7~5.0μm, and the surface protection adhesive tape for the inner surface of the semiconductor wafer has a total light transmittance of 40-80% at a wavelength of 500-600 nm, and a mirror wafer. The difference between the color difference (ΔEM) and the color difference (ΔET) in the state in which the surface protective adhesive tape for polishing the inner surface of the semiconductor wafer is bonded to the mirror wafer is ΔET-ΔEM>6.5, the surface The protective adhesive tape is used to adhere to the surface of the semiconductor wafer having the notch and to polish the inner surface of the semiconductor wafer. A surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to the first aspect of the invention, wherein the surface roughness Rz is 0.7 μm or more and less than 5.0 μm. The surface protection adhesive tape for inner surface grinding processing of a semiconductor wafer according to claim 1 or 2, wherein the substrate comprises an anthraquinone pigment, a naphthalocyanine pigment, an indanthrone Pigments, indanthrene pigments and pigments in triaryl carbocation pigments. The surface protection adhesive tape for inner surface polishing processing of a semiconductor wafer according to claim 1 or 2, wherein the substrate has a thickness of 80 to 200 μm. A surface protection adhesive tape for inner surface polishing processing of a semiconductor wafer according to claim 1 or 2, wherein the substrate is composed of a resin composed of the same copolymerization component, and the copolymerization component contains at least vinyl acetate. A surface protective adhesive tape for inner surface polishing processing of a semiconductor wafer according to claim 5, wherein the content of the vinyl acetate component is 1.9 to 10.5% by mass. The surface protection adhesive tape for inner surface polishing processing of a semiconductor wafer according to claim 1 or 2, wherein the substrate is a single layer or a plurality of layers, and the substrate does not form a substrate of the outermost layer on the side of the adhesive layer. The melting point of the resin is 85 ° C or higher. A method for polishing a semiconductor wafer is characterized in that a surface of a semiconductor wafer having a notch is bonded to a surface of a semiconductor wafer for polishing a surface protective tape to polish an inner surface of the semiconductor wafer. The surface protection adhesive tape substrate for polishing the inner surface of the semiconductor wafer is provided with an adhesive layer on one side of the substrate, and the surface roughness of the surface of the substrate on which the adhesive layer is not formed is Rz=0.7~5.0μm, the surface protection adhesive tape for the inner surface polishing of the semiconductor wafer has a total light transmittance of 40-80% at a wavelength of 500-600 nm, the color difference (ΔEM) of the mirror wafer and the semiconductor The difference in chromatic aberration (ΔET) in the state in which the surface protective adhesive tape for the inner surface polishing of the wafer is bonded to the mirror wafer is ΔET-ΔEM>6.5. The method of polishing a semiconductor wafer according to claim 8, wherein the surface roughness Rz is 0.7 μm or more and less than 5.0 μm.