TWI431091B - Wafer processing tape - Google Patents

Description

Wafer processing tape

The present invention relates to a cutting process for cutting a semiconductor wafer into a semiconductor device (wafer), and a die bonding process for cutting the wafer to be cut with a lead frame and other wafers. Wafer processing tape used.

In the manufacturing process of a semiconductor device, a process of dicing a semiconductor wafer into a wafer unit, picking up a semiconductor element (wafer) to be cut, and further attaching the picked wafer to a lead frame and Die bonding (mounting) of a package substrate or the like.

As a wafer processing tape used for the manufacturing process of the semiconductor device, a film for wafer adhesion in which an adhesive layer and an adhesive layer are sequentially formed on a base film is known (for example, see Patent Document 1).

However, when the wafer is cut by a high-speed rotating thin vermiculite (cutting blade) which is the most commonly used cutting method, as the wafer is thinned, adjacent wafers are in contact with each other due to the rotational vibration of the cutting blade. There are problems with chips such as wafer cracking or wafer defects.

In order to reduce the chipping at the time of dicing as described above, a tape for wafer processing is known, in which the thickness of the semiconductor element is W (μm), and the thickness of the adhesive layer is A (μm), and then When the storage elastic modulus at 25 ° C after the curing of the coating layer is E (GPa), the value of Q expressed by W × E / A = Q is 0.5 to 80 (see, for example, Patent Document 2).

(previous technical literature) (Patent Literature)

(Patent Document 1) Japanese Patent Laid-Open Publication No. 2002-226796

(Patent Document 2) Japanese Patent Laid-Open Publication No. 2005-026547

In the tape for wafer processing described in Patent Document 2, the relationship between the adhesive layer and the adhesive layer is not considered, and depending on the combination of the adhesive layer and the adhesive layer, wafer cracking or wafer defect cannot be prevented. The problem of chips.

Accordingly, it is an object of the present invention to provide a wafer processing tape which can reduce chipping such as wafer cracking or wafer defect during dicing.

The present inventors have found that when a semiconductor device is manufactured using a wafer processing tape having a base film, an adhesive layer provided on a base film, and an adhesive layer provided on the adhesive layer, the wafer is cut at the time of cutting. Since the contact with each other is caused by the rotational vibration of the dicing blade, it is extremely effective to make the adhesive film have a function of absorbing vibration (stress absorbing performance) in order to reduce wafer breakage or wafer defect at the time of dicing.

The present invention has been developed based on the above findings.

A tape for processing a wafer according to a first aspect of the present invention includes an adhesive film comprising a base film and an adhesive layer provided on the base film, and an adhesive layer provided on the adhesive layer. The tape for wafer processing is characterized in that the adhesive film has a function of absorbing vibration.

According to this configuration, since the adhesive film has a function of absorbing vibration, the vibration of the adhesive layer due to the rotational vibration of the dicing blade is absorbed by the adhesive film during dicing, and it is difficult to transfer to the wafer, and the adjacent wafers are lowered. s contact. Thereby, chips such as wafer cracking or wafer defect at the time of cutting are reduced.

A tape for processing a wafer according to a second aspect of the present invention is characterized in that the adhesive film has a loss tangent at 80 ° C as tan δ film, and when the loss tangent of the adhesive layer at 80 ° C is tan δad, tan δad /tan δ film is 5.0 or less.

According to this configuration, by setting tan δad/tan δ film to 5.0 or less, the adhesive film is softened to such an extent that vibration can be sufficiently absorbed. Therefore, the vibration of the adhesive layer due to the rotational vibration of the dicing blade is absorbed by the adhesive film, and it is difficult to transfer to the wafer, and the contact of the adjacent wafers (wafers of the singulated adhesive layer) with each other is reduced. Thereby, chips such as wafer cracking or wafer defect at the time of cutting are reduced. Preferably, tan δad/tan δ film is 3.4 or less.

According to the present invention, it is possible to realize a wafer processing tape which can reduce chips such as wafer cracking or wafer defects during dicing.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a cross-sectional view showing a tape 10 for wafer processing according to an embodiment. The wafer processing tape 10 has an adhesive film 12 composed of a base film 12a and an adhesive layer 12b formed thereon, and an adhesive layer 13 laminated on the adhesive film 12. As described above, the base film 12a, the adhesive layer 12b, and the adhesive layer 13 are sequentially formed on the wafer processing tape 10.

The adhesive layer 12b may be composed of a layer of an adhesive layer or a layer of an adhesive layer of two or more layers. In the first embodiment, the release liner 11 is provided on the wafer processing tape 10 in order to protect the adhesive layer 13.

The adhesive film 12 and the adhesive layer 13 may be previously cut (pre-cut) into a predetermined shape by using an engineering or a device. The tape for wafer processing of the present invention includes a form in which each piece of the semiconductor wafer is cut, and a form in which a plurality of long sheets are formed on a roll.

The wafer processing tape 10 of the present embodiment has the following configuration. When the loss tangent of 80 ° C of the adhesive film 12 is set to tan δ film, and the loss tangent of 80 ° C of the adhesive layer 13 is set to tan δad, tan δad / tan δ film is 5.0 or less. Preferably, tan δad/tan δ film is 3.4 or less.

In general, when the sample is periodically given the deformation ε, if the sample is a complete elastomer, the stress σ corresponding thereto does not occur in time delay, but is expressed in the same phase. However, when there is a viscous element on the sample, the response is sluggish (the phase difference δ between the input and response of the deformation). The deformation ε and the stress σ having such a delay are expressed by a complex elastic modulus (E ^* ) by the following formula (1).

E ^* =σ/ε

E ^* =E'+iE" (1)

In addition, the loss tangent tan δ used in the present invention is represented by the following formula (2).

Tanδ=E”/E’ (2)

Here, E' is the storage elastic coefficient, and E' is the loss elastic modulus.

The storage elastic coefficient E' indicates the elastic property, and the loss elastic modulus E" and the loss tangent tan δ indicate the properties of viscosity, that is, energy loss.

As described above, the loss tangent tan δ expressed by the ratio (E"/E') of the loss elastic modulus E" corresponding to the viscosity and the storage elastic coefficient E' corresponding to the elasticity reflects the vibration absorption property, and the value thereof is higher. Large, the higher the viscosity (softer), the higher the vibration absorption. Conversely, the smaller the value, the lower the viscosity (hardening) and the lower the vibration absorption.

When tan δad/tan δ film exceeds 5.0, the adhesive film 12 is excessively hard with respect to the adhesive layer 13, and therefore, the rotational vibration of the dicing blade 21 (Fig. 3) cannot be sufficiently absorbed by the adhesive film 12 at the time of cutting, the rotational vibration The induced vibration of the adhesive layer 13 is transmitted to the semiconductor wafer 2. Thereby, the adjacent semiconductor wafers 2 (the semiconductor wafers 2 which are singulated with the adhesive layer) are in contact with each other, resulting in wafer cracking or wafer defect. When the tan δad/tan δ film is 5.0 or less, preferably 3.4 or less, the adhesive film 12 is also soft. Therefore, the vibration of the adhesive layer 13 due to the rotational vibration of the dicing blade 21 is sufficiently absorbed by the adhesive film 12 . It is difficult to transfer to the semiconductor wafer 2. Thereby, the contact between the adjacent semiconductor wafers 2 is lowered. Thereby, chips such as wafer cracking or wafer defect at the time of cutting are reduced.

Hereinafter, each component of the wafer processing tape 10 of the present embodiment will be described in detail.

(adhesive layer)

After the semiconductor wafer 1 is bonded and diced, the semiconductor layer 1 is peeled off from the adhesive film 12 and adhered to the semiconductor wafer 2 as the semiconductor wafer 2 is fixed to the substrate or the lead frame. The agent is then used. Therefore, the adhesive layer 13 has peelability which can be peeled off from the adhesive film 12 in a state of being attached to the singulated semiconductor wafer 2 in the pick-up process, and has sufficient adhesion reliability to bond the crystal grains. In the engineering, the semiconductor wafer 2 is then fixed to a substrate or a lead frame.

The adhesive layer 13 is obtained by previously film-forming an adhesive, and for example, a well-known polyimine resin, a polyamide resin, a polyether quinone resin, or a polyamidimide may be used for the adhesive. Resin, polyester resin, polyester yttrium imide resin, phenoxy resin, polyfluorene resin, polyether oxime resin, polyphenylene sulfide resin, polyether ketone resin, chlorinated polypropylene resin, acrylic resin, polyurethane resin, ring An oxyresin, a polypropylene guanamine resin, a melamine resin or the like or a mixture thereof.

From the viewpoint of good heat resistance after hardening, it is particularly preferable to use an epoxy resin. If the epoxy resin is hardened, it can be used as a receiver. As the epoxy resin, a polyfunctional epoxy resin may be added for the purpose of high Tg (glass transition temperature), and examples of the polyfunctional epoxy resin include a phenol novolac type epoxy resin and a cresol novolak type. Epoxy resin, etc. The curing agent for the epoxy resin may be used as a curing agent for an epoxy resin, and examples thereof include amines, polyamines, acid anhydrides, polysulfides, boron trifluoride, and two or more phenols per molecule. The hydroxy group-containing compound is bisphenol A, bisphenol F, bisphenol S or the like. In particular, since it is excellent in electric corrosion resistance at the time of moisture absorption, it is preferable to use a phenol novolak resin and a bisphenol novolak resin which are phenol resins. Further, from the viewpoint of shortening the time of heat treatment for hardening, it is preferred to use a hardening accelerator together with the hardener. As the hardening accelerator, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazole may be used. A salt group such as various imidazoles such as trimellitate.

Further, in order to enhance the adhesion to the semiconductor wafer 2 or the lead frame 20, it is preferable to add a decane coupling agent or a titanium coupling agent as an additive to the above materials or a mixture thereof. Further, a filler may be added for the purpose of improving heat resistance or adjusting fluidity. As the filler shown above, there are cerium oxide, aluminum oxide, cerium oxide, and the like. If the fillers have a maximum particle diameter smaller than the thickness of the adhesive layer 13, the fillers having different particle diameters may be blended in any ratio.

In order to increase tan δad, a low molecular weight component such as an epoxy resin or a phenol resin may be added to reduce a high molecular weight component such as an acrylic resin. Further, when the filler is blended, the amount of filler blending can be reduced, and in order to lower the tan δ, it can be carried out in reverse.

The thickness of the subsequent agent layer 13 is not particularly limited, but is usually about 5 to 100 μm. Further, the adhesive layer 13 may be laminated on the entire surface of the adhesive layer 12b of the adhesive film 12, or may be an adhesive which is previously cut (pre-cut) into a shape corresponding to the bonded semiconductor wafer 1. The layers are laminated on a portion of the adhesive layer 12b. When the adhesive layer 13 cut into the shape corresponding to the semiconductor wafer 1 is laminated, as shown in FIG. 2, the adhesive layer 13 is attached to the portion where the semiconductor wafer 1 is bonded, and is bonded. The portion of the annular frame 20 for dicing does not have the adhesive layer 13, and only the adhesive layer 12b of the adhesive film 12 is present. In general, the adhesive layer 13 is difficult to be peeled off from the adherend, and therefore, by using the pre-cut adhesive layer 13, it is possible to obtain an effect that the annular frame 20 can be attached to the adhesive film 12 and used. When the subsequent sheet is peeled off, it is difficult to produce a residual slurry in the annular frame.

(adhesive film)

The adhesive film 12 has sufficient adhesive force so that the semiconductor wafer 1 does not peel off when the semiconductor wafer 1 is diced, and has a low adhesive force, and can be easily removed from the semiconductor wafer 2 after the dicing. The agent layer 13 is then peeled off. In the present embodiment, as shown in Fig. 1, the adhesive film 12 is an adhesive film in which the adhesive layer 12b is provided on the base film 12a.

The base film 12a of the adhesive film 12 can be used without any particular limitation as long as it is a conventionally known base film. As will be described later, in the present embodiment, the adhesive layer 12b is used. A radiation-curable material in an energy-hardenable material, and therefore, a radiation-transmitting property is used.

For example, examples of the material of the base film 12a include polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, and ethylene-vinyl acetate copolymer. a homopolymer or copolymer of an ethylene-ethyl acrylate copolymer, an ethylene-methyl acrylate copolymer, an ethylene-acrylic acid copolymer, an ionomer, or the like, or a mixture of such compounds; a polyurethane, styrene-ethylene- A thermoplastic elastomer such as a butene copolymer or a pentene copolymer, a polyamine-polyol copolymer, or a mixture of such compounds. Further, the base film 12a may be a mixture of two or more materials selected from the group, or may be obtained by performing a single layer or a stratification. The thickness of the base film 12a is not particularly limited, and may be appropriately set, and is preferably 50 to 200 μm.

Tan δ film is caused by the structure of the resin of the base film 12a. More specifically, the higher the molecular weight and the smaller the molecular weight between the entangled points, the higher the tan δ film.

In the present embodiment, the adhesive film 12b is cured by irradiating the adhesive film 12 with radiation such as ultraviolet rays, whereby the adhesive layer 12b can be easily peeled off from the adhesive layer 13, and therefore, it is preferably in the resin of the adhesive layer 12b. A well-known chlorinated polypropylene resin, acrylic resin, polyester resin, polyurethane resin, epoxy resin, addition reaction type organic polyoxyalkylene resin, hydrazine acrylate resin, ethylene used in the proper mixing of the adhesive Various elastic properties such as vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-acrylic acid copolymer, polyisoprene or styrene ‧ butadiene copolymer or hydrogenated product thereof The adhesive is prepared by appropriately blending a radiation polymerizable compound or the like in a mixture thereof. In addition, various surfactants or surface smoothing agents may also be added. The thickness of the adhesive layer is not particularly limited and may be appropriately set, and is preferably 5 to 30 μm.

The radiation polymerizable compound is, for example, a low molecular weight compound having at least two photopolymerizable carbon-carbon double bonds in a molecule which can be three-dimensionally networked by light irradiation, or a photopolymerizable carbon in a substituent. A carbon double bond based polymer or oligomer. Specifically, trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate or oligomeric acrylate, etc., acrylate or the like, acrylic acid or a copolymer of various acrylates.

Further, in addition to the acrylate-based compound as described above, a urethane acrylate-based oligomer can also be used. A urethane acrylate oligomer is an acrylate or methacrylate having a hydroxyl group (for example, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, methyl 2-hydroxypropyl acrylate, polyethylene glycol acrylate, polyethylene glycol methacrylate, etc.) is reacted with a terminal isocyanate urethane prepolymer, the terminal isocyanate urethane prepolymer A polyol compound such as a polyester type or a polyether type, and a polyvalent isocyanate compound (for example, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 1,3-benzenedimethyl diisocyanate, 1,4) - Benzyl diisocyanate, diphenylmethane 4,4-diisocyanate, etc.) obtained by reaction. In addition, two or more types selected from the above resins may be mixed in the adhesive layer 12b.

In addition, in the resin of the adhesive layer 12b, in addition to the radiation polymerizable compound which irradiates the adhesive film 12 with radiation, and the adhesive layer 12b is hardened, an acrylic adhesive, a photoinitiator, a hardener, etc. may be mix|blended suitably. The adhesive layer 12b is prepared.

When a photopolymerization initiator is used, for example, benzoin isopropyl ether, benzoin isobutyl ether, benzophenone, michelone, chlorothioxanthone, dodecylthioxanthone, dimethyl group can be used. Thioxanthone, diethylthioxanthone, benzyldimethylketal, α-hydroxycyclohexyl phenyl ketone, 2-hydroxymethylphenylpropane, and the like. The blending amount of the photopolymerization initiator is preferably 0.01 to 5 parts by mass based on 100 parts by mass of the acrylic copolymer.

(How to use the tape for wafer processing)

In the manufacturing process of a semiconductor device, the wafer processing tape 10 is used as follows. In the second drawing, the case where the semiconductor wafer 1 and the annular frame 20 are bonded to the wafer processing tape 10 is shown. First, as shown in Fig. 2, the adhesive layer 12b of the adhesive film 12 is adhered to the annular frame 20, and the semiconductor wafer 1 and the adhesive layer 13 are bonded to each other. The order of the adhesion is not limited, and after the semiconductor wafer 1 and the adhesive layer 13 are bonded together, the adhesive layer 12b of the adhesive film 12 is adhered to the annular frame 20. Further, the adhesion of the adhesive film 12 to the annular frame 20 and the bonding of the semiconductor wafer 1 to the adhesive layer 13 can be performed simultaneously.

Then, the dicing process of the semiconductor wafer 1 (Fig. 3) is carried out, and then, the process of irradiating the adhesive film 12 with an energy ray, for example, an ultraviolet ray, is performed. Specifically, in order to diced the semiconductor wafer 1 and the adhesive layer 13 by the dicing blade 21, the wafer processing tape 10 is adsorbed and supported from the surface side of the adhesive film 12 by the adsorption stage 22. Then, the semiconductor wafer 1 and the adhesive layer 13 are cut into a two-unit semiconductor wafer by the dicing blade 21, and diced, and then the energy ray is irradiated from the lower surface side of the adhesive film 12. By the irradiation of the energy ray, the adhesive layer 12b is hardened to lower the adhesive force. Among them, in place of the irradiation of the energy ray, the adhesion of the adhesive layer 12b of the adhesive film 12 can be lowered by external stimuli such as heating. When the adhesive layer 12b is composed of two or more adhesive layers, one or all layers in each adhesive layer may be hardened by energy ray irradiation to make one or all layers in each adhesive layer. The adhesion is reduced.

Thereafter, as shown in FIG. 4, an expansion process of stretching the adhesive film 12 of the cut semiconductor wafer 2 and the adhesive layer 13 in the circumferential direction of the annular frame 20 is performed. Specifically, the adhesive film 12 in a state in which a plurality of semiconductor wafers 2 and an adhesive layer 13 are cut is held, and the hollow cylindrical shape ejecting member 30 is lifted from the lower surface side of the adhesive film 12, so that the adhesive film 12 faces The annular frame 20 is stretched in the circumferential direction. By expanding the project, the interval between the semiconductor wafers 2 is widened, the visibility of the semiconductor wafer 2 obtained by the CCD camera or the like is improved, and at the same time, the semiconductor generated by the adjacent semiconductor wafers 2 contacting each other at the time of pickup can be prevented. The wafers are followed by each other.

After the expansion project is carried out, as shown in FIG. 5, the pick-up process of picking up the semiconductor wafer 2 is performed in a state where the adhesive film 12 is expanded. Specifically, the semiconductor wafer 2 is ejected from the lower surface side of the adhesive film 12 by the pin 31, and the semiconductor wafer 2 is adsorbed by the adsorption jig 32 from the upper surface side of the adhesive film 12, whereby the singulated semiconductor wafer is diced. 2 is picked up together with the adhesive layer 13.

Moreover, after the picking up project is carried out, the die bonding process is carried out. Specifically, the semiconductor wafer 2 is next to a lead frame or a package substrate or the like by using the adhesive layer 13 picked up together with the semiconductor wafer 2 in the pickup process.

Next, an embodiment of the present invention will be described, but the present invention is not limited to the embodiments.

The adhesive film (A) to (C) having the adhesive layers (A) to (C) shown in Table 1 and the adhesive films (1) to (3) were respectively cut into a circular shape having a diameter of 370 mm and 320 mm, and the adhesive film (1) to (1) was adhered. The adhesive layer of any of 3) is bonded to the adhesive layer of the adhesive film which has any of the adhesive layers (A)-(C). Finally, the PET film of the next film was peeled off from the adhesive layer, and each of the wafer processing tapes of Examples 1 to 4 and Comparative Examples 1 to 5 shown in Table 1 was obtained.

(production of adhesive layer)

<Binder layer (A)>

YDCN-703 (trade name, manufactured by Tohto Kasei Co., Ltd., cresol novolak type epoxy resin, epoxy equivalent 210 g/eq, molecular weight 1200, softening point 80 ° C), 50 parts by weight of phenol resin Milex XLC-LL (trade name of Mitsui Chemicals Co., Ltd., hydroxyl equivalent: 175 g/eq, water absorption: 1.8%, heating weight reduction rate at 350 ° C, 4%) 50 parts by weight, Z-6044 as a decane coupling agent 0.35 parts by weight of the product name of Toray Dow Corning Co., Ltd., 3-glycidoxypropylmethyl methoxy decane, and S0-C2 as a cerium oxide filler (trade name, specific gravity of Admatechs) 2.2 g/cm ³ , Mohs hardness 7, average particle diameter 0.5 μm, specific surface area 6.0 m ² /g) 35 parts by weight, Curezol 2PZ as a hardening accelerator (trade name of Shikoku Kasei Co., Ltd., 2-benzene) 3 parts by weight of acetonitrile, SG-P3 (trade name of Nagase chemteX, product weight average molecular weight 850,000, glass transition temperature: 10 ° C), 250 parts by weight of an acrylic resin, and stirred in an organic solvent to obtain an adhesive layer Composition. This adhesive layer composition was applied onto a release-treated polyethylene terephthalate (PET) film and dried to prepare a subsequent film having an adhesive layer (A) having a film thickness of 20 μm. The loss tangent tan δad at 80 ° C before curing obtained by dynamic viscoelasticity measurement of the adhesive layer (A) was 0.162. The method for measuring the loss tangent tan δad will be described later.

<Binder layer (B)>

YDCN-703 (trade name, manufactured by Tohto Kasei Co., Ltd., cresol novolak type epoxy resin, epoxy equivalent 210 g/eq, molecular weight 1200, softening point 80 °C) as an epoxy resin, 55 parts by weight as a phenol resin Milex XLC-LL (trade name of Mitsui Chemicals Co., Ltd., hydroxyl equivalent: 175 g/eq, water absorption: 1.8%, heating weight reduction rate at 350 ° C, 4%) 45 parts by weight, Z-6044 as a decane coupling agent 0.3 g parts by trade name of Toray Dow Corning Co., Ltd., 3-glycidoxypropylmethyl methoxy decane, and S0-C2 as a cerium oxide filler (product name, specific gravity, manufactured by Admatechs) 2.2g / cm ^3, Mohs hardness of 7, an average particle diameter of 0.5μm, 30 parts of a specific surface area 6.0m ² / g) by weight as a hardening accelerator Curezol 2PZ (Shikoku Chemicals (shares) trade name, 2-phenylethyl 0.4 parts by weight of imipenem), 275 parts by weight of SG-P3 (trade name, manufactured by Nagase chemteX, weight average molecular weight: 850,000, glass transition temperature: 10 ° C) as an acrylic resin, and stirred in an organic solvent to obtain an adhesive layer. Composition. This adhesive layer composition was applied onto a release-treated polyethylene terephthalate (PET) film and dried to prepare a subsequent film having an adhesive layer (B) having a film thickness of 20 μm. The loss tangent tan δad at 80 ° C before hardening obtained by the dynamic viscoelasticity measurement of the adhesive layer (B) was 0.232.

<Binder layer (C)>

YDCN-703 (trade name, manufactured by Tohto Kasei Co., Ltd., cresol novolak type epoxy resin, epoxy equivalent 210 g/eq, molecular weight 1200, softening point 80 ° C) as an epoxy resin, 55 parts by weight as a phenol resin Milex XLC-LL (trade name of Mitsui Chemicals Co., Ltd., hydroxyl equivalent: 175 g/eq, water absorption: 1.8%, heating weight reduction rate at 350 ° C, 4%) 45 parts by weight, Z-6044 as a decane coupling agent 1.5 parts by weight of Toray Dow Corning Co., Ltd., 3-glycidoxypropylmethyl methoxy decane, and S0-C2 as a cerium oxide filler (product name, specific gravity, manufactured by Admatechs) 2.2 g/cm ³ , Mohs hardness 7, average particle diameter 0.5 μm, specific surface area 6.0 m ² /g) 150 parts by weight, Curezol 2PZ as a hardening accelerator (trade name of Shikoku Kasei Co., Ltd., 2-benzene) 0.5 parts by weight of a acetonitrile resin, SG-P3 (trade name of Nagase chemte X (trade name, weight average molecular weight: 850,000, glass transition temperature: 10 ° C), 100 parts by weight of an acrylic resin, and stirred in an organic solvent to obtain an adhesive layer Composition. This adhesive layer composition was applied onto a release-treated polyethylene terephthalate (PET) film and dried to prepare a subsequent film having an adhesive layer (C) having a film thickness of 20 μm. The loss tangent tan δad of 80 ° C before hardening obtained by dynamic viscoelasticity measurement of the adhesive layer (C) was 0.619.

(production of adhesive film)

<Adhesive film (1)>

65 parts by weight of butyl acrylate, 25 parts by weight of 2-hydroxyethyl acrylate, and 10 parts by weight of acrylic acid were subjected to radical polymerization, and 2-isocyanate ethyl methacrylate was added dropwise to carry out a reaction to synthesize an acrylic acid having a weight average molecular weight of 800,000. To the copolymer, 3 parts by weight of a polyisocyanate as a curing agent and 1 part by weight of 1-hydroxy-cyclohexyl-phenyl-ketone as a photopolymerization initiator were added and mixed to prepare an adhesive layer composition.

The obtained adhesive layer composition was applied to a coating film (a film for coating other than the base film 12a) so as to have a dry film thickness of 10 μm, and dried at 120 ° C for 3 minutes. Thereafter, the adhesive layer composition coated on the film was used as the base film 12a, and was transferred onto a polypropylene-elastomer (PP:HSBR=80:20 elastomer) resin film having a thickness of 100 μm. Thereby, an adhesive film (1) is produced. The 80 ° C loss tangent tan δ film of the dynamic viscoelasticity of the adhesive film (1) was 0.098.

Among them, polypropylene (PP) was made using Novatec FG4 manufactured by Polychem Co., Ltd., Japan, and hydrogenated styrene butadiene (HSBR) was made using DYNARON 1320P manufactured by JSR Corporation. Further, the film for coating was a PET film (People: Purex S-314, thickness: 25 μm) which was subjected to release treatment with an anthrone.

<Adhesive film (2)>

As the base film 12a, an ethylene-methacrylic acid-(2-methyl-propyl acrylate) terpolymer-Zn++-ionomer resin (Mitsubishi-DuPont Polymer Chemical Co., Ltd.) having MFR 1.2 and a melting point of 71 ° C was used. It is produced in the same manner as the adhesive film (1) except for Mitsui-Dupont Polychemicals Co., manufactured by HIMILAN AM-7316. The 80 ° C loss tangent tan δ film of the dynamic film of the adhesive film (2) was 0.068.

<Adhesive film (3)>

As the base film 12a, an ethylene-methacrylic acid-(2-methyl-propyl) terpolymer resin (Mitsui-Dupont Polychemicals Co. Other than NUCREL AN4217-3C), it was produced in the same manner as the adhesive film (1). The 80 ° C loss tangent tan δ film of the dynamic viscoelasticity of the adhesive film (3) was 0.016.

(loss angle tangent of the adhesive layers (A) to (C))

Preparation of two 20 μm adhesive layers (A) on a separation membrane (PET), bonding them to each other with the adhesive layer (A), and peeling off the separation membrane, and further repeating each other by the adhesive layer (A) The work of coating the 20 μm adhesive layer (A) on the separation membrane was carried out, laminated to a thickness of 1 mm, and punched into a thickness of 8 mm Φ to form a sample of the adhesive layer (A).

Using a dynamic viscoelasticity measuring apparatus ARES (manufactured by REOLOGICA Co., Ltd.), the sample of the adhesive layer (A) before curing was measured at a temperature rising rate of 10 ° C under a shearing condition of a sample thickness of 1 mm, a plate diameter of 8 mm Φ, and a frequency of 1 Hz. The loss tangent tan δad of the adhesive layer (A) at 80 ° C when the temperature is raised from room temperature to 200 ° C under the conditions of /min. The loss tangent tan δad of the subsequent agent layer (B) and the adhesive layer (C) was also measured in the same manner as the loss tangent tan δad of the adhesive layer (A).

(The loss tangent of the adhesive films (1) to (3))

The adhesive films (1) to (3) were each cut into a sample having a width of 5 mm. Using a dynamic viscoelasticity measuring apparatus RSAIII (manufactured by TA Instrument Co., Ltd.), it was measured that the temperature was raised from -10 ° C to 150 ° C at a temperature increase rate of 10 ° C / min under a stretching condition of a suction cup pitch of 20 mm and a frequency of 10 Hz. The lossy tangent tan δ film of the adhesive film (1). The loss tangent tan δfilm of the adhesive film (2) and the adhesive film (3) was also measured in the same manner as the loss tangent tan δ film of the adhesive film (1).

(chip performance)

Each of the wafer processing tapes of Examples 1 to 4 and Comparative Examples 1 to 5 was adhered to the back surface of a ruthenium wafer having a thickness of 200 μm, and cut into 7.5 mm × 7.5 mm, and then the cross section of the mold was observed with an optical microscope to evaluate whether the wafer was defective or not. . As shown in Table 1, the case where the wafer was broken was set to ××, the occurrence of a plurality of wafer defects was set to ×, the wafer defect was found to be Δ, and the case where almost no wafer defect was observed was set as ○ Perform chip evaluation.

As is clear from Table 1, in Examples 1 to 4, chips such as wafer cracking or wafer defects during cutting (chip chips at the time of cutting) were sufficiently lowered.

On the other hand, in Comparative Examples 1 to 5, chips such as wafer cracking or wafer defect at the time of dicing were generated.

According to the wafer processing tape 10 of the present embodiment, the tan δad/tan δ film of the loss tangent tan δ film of the adhesive film 12 at 80° C. and the loss tangent tan δad of the adhesive layer 13 at 80° C. is set to 5.0 or less. The rotational vibration of the cutter blade 21 (Fig. 3) is sufficiently absorbed by the adhesive film 12. At the time of cutting, the vibration due to the rotational vibration of the dicing blade 21 of the adhesive layer 13 is sufficiently absorbed by the adhesive film 12, whereby it is difficult to be transmitted to the semiconductor wafer 2. Thereby, the contact between the adjacent semiconductor wafers 2 is reduced, and chips such as wafer cracking or wafer defect at the time of dicing are reduced.

By setting the above ratio tan δad/tan δ film to 3.4 or less, as shown in Table 1, wafer rupture or wafer defect at the time of dicing hardly occurred. Therefore, chips such as wafer cracking or wafer defects at the time of cutting can be sufficiently reduced.

1. . . Semiconductor wafer

2. . . Semiconductor wafer (semiconductor component)

10. . . Wafer processing tape

11. . . Release liner

12. . . Adhesive film

12a. . . Substrate film

12b. . . Adhesive layer

13. . . Subsequent layer

20. . . Lead frame

twenty one. . . Cutting knife

twenty two. . . Adsorption station

30. . . Ejecting member

31. . . pin

32. . . Adsorption fixture

Fig. 1 is a cross-sectional view showing a tape for wafer processing according to an embodiment of the present invention.

Fig. 2 is a view in which a semiconductor wafer is bonded to a tape for wafer processing.

Figure 3 is a diagram for explaining the cutting process.

Fig. 4 is a diagram for explaining an extended project.

Figure 5 is a diagram for explaining the picking up project.

1. . . Semiconductor wafer

2. . . Semiconductor wafer (semiconductor component)

10. . . Wafer processing tape

12. . . Adhesive film

12a. . . Substrate film

12b. . . Adhesive layer

13. . . Subsequent layer

20. . . Lead frame

twenty one. . . Cutting knife

twenty two. . . Adsorption station

Claims (2)

A tape for processing a wafer, comprising: an adhesive film comprising a base film and an adhesive layer provided on the base film; and a wafer processing tape provided on an adhesive layer provided on the adhesive layer The substrate film is a thickness of 50 to 200 μm selected from the group consisting of polyethylene, polypropylene, ethylene-propylene copolymer, polybutene-1, poly-4-methylpentene-1, ethylene-vinyl acetate. a homopolymer or copolymer of an α-olefin such as an ester copolymer, an ethylene-ethyl acrylate copolymer, an ethylene-methyl acrylate copolymer, an ethylene-acrylic acid copolymer, an ionomer, or a mixture of such compounds; a polyurethane, benzene a base film of a thermoplastic elastomer such as an ethylene-ethylene-butene copolymer, a pentene copolymer or a polyamine-polyol copolymer, or a mixture of the compounds, the adhesive layer having an energy hardening thickness of 5 to 30 μm The adhesive layer, the adhesive layer is an adhesive layer containing epoxy resin having a thickness of 5 to 100 μm, and the loss tangent of the adhesive film at 80 ° C is set to tan δ film, and the adhesive layer is at a loss angle of 80 ° C. Tangent setting to tan δa In the case of d, the tan δad/tan δ film is 5.0 or less, and the adhesive film has a function of absorbing vibration. The tape for wafer processing according to the first aspect of the invention, wherein the tan δad/tan δ film is 3.4 or less.