JP2017005160A - Tape for wafer processing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tape for wafer processing capable of efficiently transferring tensile force to a semiconductor wafer and an adhesive layer pasted to the semiconductor wafer and preventing the semiconductor wafer from being contaminated by the broken pieces of the adhesive layer.SOLUTION: Disclosed is a tape for wafer processing which includes a self-adhesive film in which a self-adhesive layer is directly or indirectly provided on a base material film, and an adhesive layer directly or indirectly formed on the self-adhesive film and which is used for processing of a semiconductor wafer. The diameter of the self-adhesive layer is 1.01 to 1.06 times diameters of the semiconductor wafer.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a wafer processing tape, and more particularly to a wafer processing tape having two functions of a dicing tape and a die bonding film.

  In the manufacturing process of a semiconductor device such as an IC, a back grinding process for grinding the back surface of the semiconductor wafer in order to reduce the thickness of the semiconductor wafer after the circuit pattern is formed. After bonding, the dicing process to divide the semiconductor wafer into chips, the expanding process to expand (expand) the wafer processing tape, the pick-up process to pick up the divided chips, and the picked-up chips to lead frames and packages A die bonding (mounting) step of bonding to a substrate or the like (or stacking and bonding chips in a stacked package) is performed.

  In the back grinding process, a surface protection tape is used to protect the circuit pattern forming surface (wafer surface) of the semiconductor wafer from contamination. When the surface protection tape is peeled off from the semiconductor wafer surface after the backside grinding of the semiconductor wafer is completed, the wafer processing tape (dicing / die bonding tape) described below is bonded to the backside of the semiconductor wafer and then placed on the suction table. The wafer processing tape side is fixed, and the surface protection tape is subjected to a treatment for reducing the adhesive force to the semiconductor wafer, and then the surface protection tape is peeled off. The semiconductor wafer from which the surface protection tape has been peeled is then picked up from the suction table in a state where the semiconductor wafer is bonded to the back surface, and is subjected to the next dicing process. The treatment for reducing the adhesive strength is energy ray irradiation treatment when the surface protection tape is made of an energy ray curable component such as ultraviolet rays. Regardless of the constituent components of the surface protection tape, the heat treatment may be used alone as a treatment for reducing the adhesive force, or may be used in combination with other treatments such as an energy ray irradiation treatment.

  In the dicing process to the mounting process after the back grinding process, a wafer processing tape in which a pressure-sensitive adhesive layer and an adhesive layer are laminated in this order on a base film is used. In general, when a semiconductor wafer is used, first, an adhesive layer of the semiconductor wafer is bonded to the back surface of the semiconductor wafer to fix the semiconductor wafer, and the semiconductor wafer and the adhesive layer are diced into chips using a dicing blade. . Thereafter, an expanding process is performed to expand the distance between the chips by expanding the tape in the radial direction of the semiconductor wafer. This expanding process is performed in the subsequent pick-up process in order to improve chip recognition by a CCD camera or the like and to prevent chip breakage caused by contact between adjacent chips when picking up a chip. The Thereafter, the chip is peeled off from the adhesive layer together with the adhesive layer in the pickup process and picked up, and directly attached to the lead frame, the package substrate, etc. in the mounting process. In this way, by using wafer processing tape, it is possible to directly bond chips with an adhesive layer to lead frames, package substrates, etc., so the adhesive coating process and die bonding to each chip separately The step of adhering the film can be omitted.

  However, in the dicing process, as described above, since the semiconductor wafer and the adhesive layer are diced together using a dicing blade, not only semiconductor wafer cutting waste but also adhesive layer cutting waste is generated. End up. Then, when the cutting waste of the adhesive layer is clogged in the dicing groove of the semiconductor wafer, there is a problem that chips are stuck to each other to cause a pickup failure and the manufacturing yield of the semiconductor device is lowered.

  In order to solve such problems, a method is proposed in which only the semiconductor wafer is diced by the blade in the dicing process, and the adhesive tape is divided into individual chips by expanding the wafer processing tape in the expanding process. (For example, Patent Document 1). According to such a method for dividing the adhesive layer using the tension at the time of expansion, no cutting waste of the adhesive is generated, and there is no adverse effect in the pickup process.

  In recent years, a so-called stealth dicing method that can cut a semiconductor wafer in a non-contact manner using a laser processing apparatus has been proposed as a semiconductor wafer cutting method. For example, in Patent Document 2, as a stealth dicing method, an adhesive layer (die bond resin layer) is interposed, a focus light is adjusted inside a semiconductor substrate to which a sheet is attached, and laser light is irradiated. Forming a modified region by multiphoton absorption inside the semiconductor substrate, cutting the modified region into the planned cutting part, and expanding the sheet to cut the semiconductor substrate and the adhesive layer along the planned cutting part A method for cutting a semiconductor substrate comprising the steps of:

  Further, as another method for cutting a semiconductor wafer using a laser processing apparatus, for example, Patent Document 3 discloses a process of mounting an adhesive layer (adhesive film) for die bonding on the back surface of a semiconductor wafer, and the adhesive. From the surface of the semiconductor wafer on which the protective adhesive tape is bonded to the adhesive layer side of the semiconductor wafer on which the layer is bonded, and from the surface of the semiconductor wafer on which the protective adhesive tape is bonded, The process of dividing into individual chips, the process of expanding the protective adhesive tape to give tensile force to the adhesive layer, breaking the adhesive layer for each chip, and the broken adhesive layer are bonded There has been proposed a method for dividing a semiconductor wafer including a step of removing a chip from a protective adhesive tape.

  According to the semiconductor wafer cutting methods described in Patent Document 2 and Patent Document 3, since the semiconductor wafer is cut in a non-contact manner by laser light irradiation and tape expansion, the physical load on the semiconductor wafer is small. The semiconductor wafer can be cut without generating chipping (chipping) of the semiconductor wafer as in the case of performing mainstream blade dicing. Further, since the adhesive layer is divided by the expansion, cutting waste of the adhesive layer is not generated. For this reason, it attracts attention as an excellent technique that can replace blade dicing.

  As described in the above Patent Documents 1 to 3, in the method of dividing the adhesive layer by expansion, the semiconductor wafer to be used has a base material for reliably dividing the adhesive layer along the chip. The uniform and isotropic expandability of the film needs to be sufficiently transmitted to the adhesive layer.

  Therefore, by making the diameter of the adhesive layer the same as or close to the diameter of the pressure-sensitive adhesive layer, the tension applied to the wafer processing tape by the expand can be evenly applied to the adhesive layer. A wafer processing tape in which layers are uniformly stretched is disclosed (for example, see Patent Document 4). Thereby, the nonuniformity of the division | segmentation of an adhesive bond layer is lose | eliminated, and the division | segmentation property of an adhesive bond layer can be improved. Moreover, the improvement of the parting property of the adhesive layer has the effect of reducing the time and labor required to optimize the expanding conditions.

JP 2007-5530 A JP 2003-338467 A JP 2004-273895 A JP 2009-094127 A

  In the wafer processing tape described in Patent Document 4, the adhesive layer present on the outside of the semiconductor wafer is used to mount the chip after the semiconductor wafer is separated into a substrate or another chip. Not an unnecessary part. By increasing this unnecessary portion, the tension to be transmitted to the semiconductor wafer or the adhesive layer bonded to the semiconductor wafer is reduced. In addition, a portion that is not bonded to the semiconductor wafer is subjected to a large tension, so that the portion is broken randomly and the semiconductor wafer is contaminated with fragments of the adhesive layer generated thereby.

  Therefore, the present invention is capable of efficiently transmitting tension to a semiconductor wafer or an adhesive layer bonded to the semiconductor wafer, and prevents the semiconductor wafer from being contaminated by fragments of the adhesive layer. It is an object to provide a tape for use.

  In order to solve the above problems, a wafer processing tape according to the present invention includes an adhesive film in which an adhesive layer is provided directly or indirectly on a base film, and directly or indirectly on the adhesive film. And a wafer processing tape used for processing a semiconductor wafer, wherein the diameter of the adhesive layer is 1.01 to 1.06 of the diameter of the semiconductor wafer. It is characterized by being double.

  The wafer processing tape preferably has a peeling force between the adhesive layer and the adhesive film of 0.4 to 2.0 N / 25 mm.

The wafer processing tape is preferably used in a method for manufacturing a semiconductor device including at least the following steps in any order.
(A) A step of bonding the adhesive layer to the back surface of the semiconductor wafer while the semiconductor wafer is heated;
(B) forming a dividing line with a laser beam or a blade at a part to be divided of the semiconductor wafer;
(C) dividing the semiconductor wafer and the adhesive layer along a dividing line by expanding the adhesive film, and obtaining a plurality of semiconductor chips with the adhesive layer;
(D) Step of picking up the semiconductor chip with the adhesive layer from the pressure-sensitive adhesive layer

The wafer processing tape may be used in a method for manufacturing a semiconductor device including at least the following steps in any order.
(A) A step of bonding the adhesive layer to the back surface of the semiconductor wafer while the semiconductor wafer is heated;
(B) a step of forming a modified region by multiphoton absorption inside the wafer by irradiating a laser beam with a focused light inside the portion to be divided of the semiconductor wafer;
(C) a step of dividing the semiconductor wafer and the adhesive layer along the planned cutting portion by expanding the adhesive film to obtain a plurality of semiconductor chips with the adhesive layer;
(D) Step of picking up the semiconductor chip with the adhesive layer from the pressure-sensitive adhesive layer

The wafer processing tape may be used in a method for manufacturing a semiconductor device including at least the following steps in any order.
(A) cutting the semiconductor wafer to a depth less than the thickness of the wafer along a line to be cut using a laser beam or a dicing blade;
(B) a step of bonding a surface protection tape to the surface of the semiconductor wafer;
(C) a back grinding process for dividing the semiconductor wafer into the semiconductor chips by grinding the back surface of the semiconductor wafer;
(D) A step of bonding the adhesive layer to the back surface of the wafer divided into the semiconductor chips while the semiconductor wafer is heated;
(E) Step of peeling a semiconductor surface protection tape from the surface of the semiconductor wafer divided into the semiconductor chips (f) By dividing the adhesive film, the adhesive layer is divided corresponding to the semiconductor chips, Obtaining a plurality of semiconductor chips with the adhesive layer;
(G) A step of picking up the semiconductor chip with the adhesive layer from the pressure-sensitive adhesive layer

  ADVANTAGE OF THE INVENTION According to this invention, tension | tensile_strength can be efficiently transmitted to the adhesive bond layer bonded to the semiconductor wafer or the semiconductor wafer, and it can prevent that a semiconductor wafer is contaminated with the fragment of an adhesive bond layer.

It is sectional drawing which shows typically an example of the tape for wafer processing of this invention. It is a top view which shows typically the relationship between the diameter of the adhesive bond layer of the tape for wafer processing of this invention, and the diameter of a semiconductor wafer. It is sectional drawing which shows the state by which the surface protection tape was bonded by the wafer. It is sectional drawing for demonstrating the process of bonding a wafer and a ring frame to the tape for semiconductor processing which concerns on embodiment of this invention. It is sectional drawing explaining the process of peeling a surface protection tape from the surface of a wafer. It is sectional drawing which shows a mode that the modification | reformation area | region was formed in the wafer by laser processing. (A) It is sectional drawing which shows the state with which the tape for semiconductor processing which concerns on embodiment of this invention was mounted in the expand apparatus. (B) It is sectional drawing which shows the process in which a wafer is divided | segmented into a chip | tip by expansion of the tape for semiconductor processing. (C) It is sectional drawing which shows the tape for semiconductor processing after expansion, an adhesive bond layer, and a chip | tip. It is sectional drawing for demonstrating a heat shrink process.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing an example of a wafer processing tape (dicing / die bonding tape) according to an embodiment of the present invention.

  As shown in FIG. 1, the wafer processing tape 10 includes a pressure-sensitive adhesive film 15 in which a pressure-sensitive adhesive layer 12 is directly or indirectly provided on a base film 11 and a pressure-sensitive adhesive film 15 directly or indirectly. And an adhesive layer 13 formed on the substrate. The wafer processing tape 10 may be provided with a release film (not shown) on the adhesive layer 13.

  Hereafter, each component of the tape 10 for wafer processing of this embodiment is demonstrated in detail.

(Adhesive film 15)
The adhesive film 15 is not particularly limited, and has a sufficient adhesive force so that the wafer does not peel when dicing the wafer, and can be easily peeled from the adhesive layer when picking up the chip after dicing. Although what shows a low adhesive force is sufficient, what showed the adhesive layer 12 to the base film 11 can be used conveniently as shown in this Embodiment.

  As the base film 11 of the adhesive film 15, a polyester film such as a polyethylene terephthalate film, a polytetrafluoroethylene film, a polyethylene film, a polypropylene film, a polymethylpentene film, a polyolefin film such as a polyvinyl acetate film, or a polyvinyl chloride film , Plastic films such as polyimide films, and the like, and mixtures thereof may be used, and these may have a multilayer structure.

  The thickness of the base film 11 is appropriately selected within a range that does not impair workability. However, when a high energy ray (in particular, ultraviolet ray) curable pressure sensitive adhesive is used as the pressure sensitive adhesive constituting the pressure sensitive adhesive layer 12, the thickness does not hinder the transmission of the high energy ray. Usually, it is 10-500 micrometers, Preferably it is 50-200 micrometers.

  In order to improve the adhesion between the base film 11 and the pressure-sensitive adhesive layer 12, the surface of the base film is chemically or physically subjected to chromic acid treatment, ozone exposure, flame exposure, high-voltage impact exposure, ionizing radiation treatment, etc. A surface treatment may be applied.

  Further, in the present embodiment, the pressure-sensitive adhesive layer 12 is provided directly on the base film 11, but a primer layer for improving adhesion, an anchor layer for improving machinability during dicing, stress You may provide indirectly through a relaxation layer, an antistatic layer, etc.

  As the pressure-sensitive adhesive used for the pressure-sensitive adhesive layer 12 of the pressure-sensitive adhesive film 15, a pressure-sensitive adhesive having an adhesive force at room temperature and having an adhesive force to the base film 11 is preferable. As the pressure-sensitive adhesive constituting the pressure-sensitive adhesive layer 12, acrylic resin, various synthetic rubbers, natural rubber, polyimide resin, and the like can be used. As the acrylic resin, for example, an acrylic copolymer having a weight average molecular weight of 100,000 to 800,000 is suitably used. As the pressure-sensitive adhesive, those that are cured by high energy rays such as ultraviolet rays and radiation or heat (that is, the pressure-sensitive adhesive force can be reduced) are more preferable.

   As the pressure-sensitive adhesive which is cured by high energy rays (or ultraviolet rays), those whose adhesive strength is reduced by irradiation with high energy rays (or ultraviolet rays) are particularly preferable. In the case of curing using an energy beam, it is preferable to contain an energy beam curing adhesive component.

  The thickness of the pressure-sensitive adhesive layer 12 is usually 1 to 100 μm, preferably 2 to 30 μm, and more preferably 3 to 30 μm.

(Release film)
The release film is for improving the handleability of the adhesive layer 13 and protecting the adhesive layer 13. The release film used for the wafer processing tape 10 of the present invention includes polyester (PET, PBT, PEN, PBN, PTT), polyolefin (PP, PE), and copolymers (EVA, EEA, EBA). Moreover, these materials can be partially substituted to use a film with improved adhesion and mechanical strength. Moreover, the laminated body of these films may be sufficient.

  The thickness of the release film is not particularly limited and may be appropriately set, but is preferably 25 to 50 μm.

(Adhesive layer 13)
The adhesive layer 13 is attached to the back surface of the chip when the chip is picked up after the semiconductor wafer or the like is bonded and diced, and is used as an adhesive for fixing the chip to the substrate or the lead frame. Is. The adhesive layer 13 has a circular label shape corresponding to the shape of the wafer.

  Examples of the resin constituting the adhesive layer 13 include, as a base resin, polyimide, polystyrene, polyethylene, polyester, polyamide, butadiene rubber, acrylic rubber, (meth) acrylic resin, urethane resin, polyphenylene ether resin, and polyetherimide resin. , Phenoxy resins, modified polyphenylene ether resins, phenoxy resins, polycarbonates, and mixtures thereof, including those having film-forming properties. The proportion of the base resin is preferably 30 to 85% by mass with respect to the total amount of the resin.

  In particular, the base resin contains a high molecular weight component including a functional monomer having a weight average molecular weight of 100,000 or more, for example, a functional monomer such as glycidyl acrylate or glycidyl methacrylate, and a weight average molecular weight of 100,000 or more. An epoxy group-containing (meth) acrylic copolymer is preferred.

  As the epoxy group-containing (meth) acrylic copolymer, for example, (meth) acrylic ester copolymer, acrylic rubber and the like can be used, and acrylic rubber is more preferable. The acrylic rubber is a rubber mainly composed of an acrylate ester and mainly composed of a copolymer such as butyl acrylate and acrylonitrile, a copolymer such as ethyl acrylate and acrylonitrile, or the like.

  In addition to the above, a preferable base resin includes a phenoxy resin. The phenoxy resin is preferably a resin obtained by a method of reacting various bisphenols with epichlorohydrin or a method of reacting a liquid epoxy resin with bisphenol. As the bisphenol, bisphenol A, bisphenol bisphenol AF, bisphenol AD, bisphenol F Bisphenol S. The phenoxy resin is similar in structure to the epoxy resin and thus has good compatibility with the epoxy resin and is preferable for imparting good adhesiveness to the adhesive film.

Examples of the phenoxy resin used in the present invention include a resin having a repeating unit represented by the following general formula (1).

In the general formula (1), X represents a single bond or a divalent linking group. Examples of the divalent linking group include an alkylene group, a phenylene group, —O—, —S—, —SO—, and —SO ₂ —. Here, the alkylene group is preferably an alkylene group having 1 to 10 carbon atoms, and more preferably —C (R ¹ ) (R ² ) —. R ¹ and R ² represent a hydrogen atom or an alkyl group, and the alkyl group is preferably a linear or branched alkyl group having 1 to 8 carbon atoms, such as methyl, ethyl, n-propyl, isopropyl, isooctyl, 2 -Ethylhexyl, 1,3,3-trimethylbutyl and the like. The alkyl group may be substituted with a halogen atom, and examples thereof include a trifluoromethyl group. X represents an alkylene group, -O -, - S-, fluorene group or -SO ₂ - is preferably an alkylene group, -SO ₂ - is more preferred. Of these, —C (CH ₃ ) ₂ —, —CH (CH ₃ ) —, —CH ₂ —, and —SO ₂ — are preferable, and —C (CH ₃ ) ₂ —, —CH (CH ₃ ) —, — CH ₂ — is more preferable, and —C (CH ₃ ) ₂ — is particularly preferable.

  As long as the phenoxy resin represented by the general formula (1) has a repeating unit, even if the X in the general formula (1) is a resin having a plurality of repeating units, X is the same repeating unit. It may consist only of. In the present invention, a resin in which X is composed of only the same repeating unit is preferable.

  When the phenoxy resin represented by the general formula (1) contains a polar substituent such as a hydroxyl group or a carboxyl group, the compatibility with the thermally polymerizable component is improved, and a uniform appearance and characteristics are imparted. be able to.

  When the weight average molecular weight of the phenoxy resin is 5000 or more, the film forming property is excellent. More preferably, it is 10,000 or more, More preferably, it is 30,000 or more. Moreover, it is preferable that the mass average molecular weight is 150,000 or less in terms of fluidity at the time of thermocompression bonding and compatibility with other resins. More preferably, it is 100,000 or less. Moreover, when the glass transition temperature is −50 ° C. or higher, it is excellent in terms of film formability, more preferably 0 ° C. or higher, and further preferably 50 ° C. or higher. When the glass transition temperature is 150 ° C., the adhesive strength of the adhesive layer at the time of die bonding is excellent, more preferably 120 ° C. or less, and still more preferably 110 ° C. or less.

  Examples of the resin constituting the adhesive layer 13 include those that are cured by heat such as an epoxy resin, a bismaleimide resin, a triazine resin, and a phenol resin as a thermosetting component. The thermosetting resin may further contain a curing agent that reacts with the thermosetting component, and may be encapsulated by coating the curing agent with a polyurethane-based or polyester-based polymer substance to increase the curing time. .

  The thermosetting component is preferably an epoxy resin and its curing agent. As the epoxy resin, for example, a bifunctional epoxy resin such as bisphenol A type epoxy, a novolak type epoxy resin such as a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, or the like can be used. Further, generally known resins such as a polyfunctional epoxy resin, a glycidylamine type epoxy resin, a heterocyclic ring-containing epoxy resin, or an alicyclic epoxy resin can be applied. As a curing agent for the epoxy resin, a phenol resin or an amine compound is preferable. It is preferable that the ratio of an epoxy resin and its hardening | curing agent is 15-70 mass% with respect to resin whole quantity.

  The adhesive layer 13 may include a coupling agent in order to increase the adhesive strength with the semiconductor wafer. Examples of the coupling agent include silane, titanium, and aluminum. Examples of the silane coupling agent include γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and 3-aminopropylmethyldisilane. Examples include ethoxysilane, 3-ureidopropyltriethoxysilane, and 3-ureidopropyltrimethoxysilane, which can be used alone or in combination of two or more.

A filler may be added to the adhesive layer 13 from the viewpoint of controlling the fluidity and improving the elastic modulus. In this case, the specific surface area has a specific surface area for the purpose of reducing the breaking strength of the adhesive sheet in the B-stage state, reducing the elongation at break, improving the handleability of the adhesive, improving the thermal conductivity, adjusting the melt viscosity, and imparting thixotropic properties. It is preferable to use a filler of 30 to 400 m ² / g. Examples of the filler include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whisker, boron nitride, and crystalline silica. And composite oxides such as amorphous silica, mullite and cordierite, montmorillonite and smectite, and the shape of the filler is not particularly limited. These fillers can be used alone or in combination of two or more. In order to improve thermal conductivity, alumina, aluminum nitride, boron nitride, crystalline silica, amorphous silica and the like are preferable. The proportion of the filler is preferably 5% by mass or more and 95% by mass or less with respect to the total weight of the composition constituting the adhesive layer 13.

  By adding an ion scavenger, the adhesive layer 13 can adsorb ionic impurities and improve insulation reliability during moisture absorption. Examples of the ion scavenger include triazine thiol compounds and bisphenol-based reducing agents, such as compounds known as copper damage inhibitors to prevent copper from ionizing and dissolving, and zirconium-based and antimony bismuth-based magnesium aluminum compounds. And inorganic ion adsorbents.

  When forming the adhesive layer 13, the thermosetting resin may be varnished. The solvent for varnishing the thermosetting resin is not particularly limited as long as it is an organic solvent, but can be determined in consideration of the volatility during film production from the boiling point. For example, a relatively low boiling point solvent such as methanol, ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, methyl isobutyl ketone, toluene, xylene does not cure the film during film production. This is preferable. These solvents can be used alone or in combination of two or more.

The adhesive layer 13 preferably has a breaking elongation at 25 ° C. in the B-stage state of more than 40%, more preferably more than 100%, still more preferably more than 150%, and the upper limit is usually about 700%.
The adhesive layer 13 is preferably laminated between 40 and 100 ° C. in order to reduce the warp of the semiconductor wafer W and improve the handleability at room temperature (25 ° C.).

  In addition to the above characteristics, the adhesive layer 13 preferably has heat resistance and moisture resistance required when a semiconductor element is mounted on a semiconductor element mounting support member.

  The adhesive layer 13 preferably has a glass transition temperature (hereinafter referred to as “Tg”) of −30 ° C. to 50 ° C. and a weight average molecular weight of 10,000 to 1,000,000. When Tg is −30 ° C. to 50 ° C., moderate flexibility is obtained, and the adhesive layer 13 is broken when the semiconductor wafer W is divided. Moreover, since a sufficient heat resistance and fluidity | liquidity are obtained as a weight average molecular weight is 10,000-1,000,000, it is preferable.

  In addition, a weight average molecular weight is a polystyrene conversion value using the calibration curve by a standard polystyrene by the gel permeation chromatography method (GPC), the Hitachi Ltd. make, brand name L-6000 is used as a pump, a column As a column made by connecting Hitachi Chemical Co., Ltd., trade names Gelpack GL-R440, Gelpack GL-R450 and Gelpack GL-R400M [each 10.7 mm (diameter) x 300 mm] in this order, As a sample, tetrahydrofuran (hereinafter referred to as “THF”) is used, and a sample in which 120 mg of sample is dissolved in 5 ml of THF can be measured at a flow rate of 1.75 mL / min.

  The thickness of the adhesive layer 13 is usually 5 to 200 μm, preferably 5 to 150 μm, more preferably 5 to 100 μm, and still more preferably 10 to 100 μm. If the thickness is less than 5 μm, it becomes difficult to secure a sufficient adhesive force with the wafer, or the convex electrodes of the circuit board cannot be filled. On the other hand, when it is thicker than 200 μm, it is uneconomical, and it tends not to meet the demand for downsizing of semiconductor devices, and there is no advantage in characteristics.

  It is preferable that the shape (planar shape) of the main surface of the adhesive layer 13 is substantially circular. And the diameter of the adhesive bond layer 13 is 1.01-1.06 times the diameter of the semiconductor wafer W which will be used in manufacture of a semiconductor device, as shown in FIG. When it is 1.01 times or more, it is preferable in that the semiconductor wafer can be prevented from protruding from the adhesive layer 13 when the semiconductor wafer is bonded to the adhesive layer 13. When it is 1.06 times or less, the portion not bonded to the semiconductor wafer of the adhesive layer 13 (peripheral portion of the semiconductor wafer) is subjected to a large tension when it is expanded, and the layer is broken randomly. Therefore, it is preferable in that the risk that the semiconductor wafer is contaminated with fragments of the adhesive layer generated thereby can be reduced.

  The adhesive layer 13 can be produced, for example, by the method described below. That is, a material obtained by dissolving the raw resin composition of the adhesive layer 13 in a solvent such as an organic solvent on a release film to form a varnish is obtained by knife coating, roll coating, spray coating, gravure coating, bar A long coating is performed by a coating method, a curtain coating method, or the like, and the solvent is removed to form the adhesive layer 13. Thereafter, a circular label shape of a predetermined size is pre-cut using a press cutting blade, and unnecessary peripheral portions are removed. Alternatively, the adhesive layer 13 can be formed by applying a circular label shape of a predetermined size in advance using a screen or the like and removing the solvent.

  Thereafter, the adhesive film 11 is laminated on the release film provided with the circular adhesive layer 13 so that the adhesive layer 13 and the adhesive layer 12 are in contact with each other. In some cases, the adhesive film 11 has a predetermined size. By pre-cutting into a circular label shape, a wafer processing tape 10 is produced.

  In the present embodiment, the adhesive layer 13 is provided directly on the pressure-sensitive adhesive layer 12, but is peeled off from the pressure-sensitive adhesive layer 12 together with the release layer for improving the pickup property and the chip and the adhesive layer 13. Then, it may be provided indirectly via a functional layer (for example, a protective layer, a heat dissipation layer, an identification layer, etc.) for imparting a function to the chip.

(Other)
The 90 ° peel peeling force between the pressure-sensitive adhesive film 15 and the adhesive layer 13 is preferably 0.4 to 2.0 N / 25 mm at a peeling speed of 300 mm / min. It is more preferably 0.4 to 1.5 N / 25 mm, and further preferably 0.4 to 1.2 N / 25 mm. When the 90 ° peel peel force between the adhesive film 15 and the adhesive layer 13 is 0.4 N / 25 mm or more, the uniform and isotropic expandability of the base film is bonded through the adhesive layer when expanded. The adhesive layer is sufficiently propagated to the adhesive layer, and the adhesive layer is efficiently divided. Moreover, in order to transmit tension | tensile_strength efficiently to an adhesive bond layer, although the one where a peeling force is larger is preferable, after extending | stretching between the adhesive film 15 and the adhesive bond layer 13 after expansion, and after reducing peeling force depending on the case, In order to peel off and obtain good pick-up performance, the upper limit of 90 ° peel peel strength is preferably about 2.0 N / 25 mm.

  The peeling force between the adhesive layer 13 and the pressure-sensitive adhesive film 15 is measured by 90 ° peel peeling force. The pressure-sensitive adhesive layer side of the pressure-sensitive adhesive film 15 is laminated on the adhesive layer 13 at room temperature to 60 ° C. After laminating the wafer to the adhesive layer 13 with a laminator set at a heating temperature of 40 to 100 ° C., a 25 mm wide cut is made and a strip for tensile measurement is prepared as a sample.

  The wafer is pressed against the stage, and one end (adhesive film 15) of the strip sample is fixed to a tensile jig of a tensile measuring machine, a 90 ° peel test is performed, and the sample is peeled off from the adhesive layer 13. By this measurement, the 90 ° peel peel force between the adhesive layer 13 and the pressure-sensitive adhesive film 15 can be measured.

<Application>
The wafer processing tape 10 of the present invention is used in a method for manufacturing a semiconductor device including an expanding process for dividing the adhesive layer 13 by at least expansion. Therefore, other processes and the order of processes are not particularly limited. For example, it can be suitably used in the following semiconductor device manufacturing methods (A) to (D).

Manufacturing method of semiconductor device (A)
(A) a step of bonding a surface protection tape to the wafer surface on which a circuit pattern is formed;
(B) a back grinding process for grinding the back surface of the wafer;
(C) A process of bonding an adhesive layer of the wafer processing tape to the back surface of the wafer while the wafer is heated;
(D) peeling the surface protection tape from the wafer surface;
(E) irradiating a laser beam to a portion to be divided of the wafer, and forming a modified region by multiphoton absorption inside the wafer;
(F) Expanding the wafer processing tape to divide the wafer and the adhesive layer of the wafer processing tape along a cutting line to obtain a plurality of chips with the adhesive layer Process,
(G) In the expanded wafer processing tape, by heating and shrinking a portion that does not overlap the chip, the slack generated in the expanding step is removed, and the interval between the chips is maintained;
(H) picking up the chip with the adhesive layer from the adhesive layer of the wafer processing tape;
A method of manufacturing a semiconductor device including:

Manufacturing method of semiconductor device (B)
(A) a step of bonding a surface protection tape to the wafer surface on which a circuit pattern is formed;
(B) a back grinding process for grinding the back surface of the wafer;
(C) A process of bonding an adhesive layer of the wafer processing tape to the back surface of the wafer while the wafer is heated;
(D) peeling the surface protection tape from the wafer surface;
(E) irradiating a laser beam along a cutting line on the wafer surface, and cutting the wafer into chips;
(F) Expanding the wafer processing tape to divide the adhesive layer for each chip and to obtain a plurality of chips with the adhesive layer;
(G) In the expanded wafer processing tape, by heating and shrinking a portion that does not overlap the chip, the slack generated in the expanding step is removed, and the interval between the chips is maintained;
(H) picking up the chip with the adhesive layer from the adhesive layer of the wafer processing tape;
A method of manufacturing a semiconductor device including:

Manufacturing method of semiconductor device (C)
(A) a step of bonding a surface protection tape to the wafer surface on which a circuit pattern is formed;
(B) a back grinding process for grinding the back surface of the wafer;
(C) A process of bonding an adhesive layer of the wafer processing tape to the back surface of the wafer while the wafer is heated;
(D) peeling the surface protection tape from the wafer surface;
(E) cutting the wafer along a cutting line using a dicing blade and cutting the wafer into chips;
(F) Expanding the wafer processing tape to divide the adhesive layer for each chip and to obtain a plurality of chips with the adhesive layer;
(G) In the expanded wafer processing tape, by heating and shrinking a portion that does not overlap the chip, the slack generated in the expanding step is removed, and the interval between the chips is maintained;
(H) picking up the chip with the adhesive layer from the adhesive layer of the wafer processing tape;
A method of manufacturing a semiconductor device including:

Manufacturing method of semiconductor device (D)
(A) cutting the wafer on which the circuit pattern is formed to a depth less than the thickness of the wafer along a line to be cut using a dicing blade;
(B) bonding a surface protective tape to the wafer surface;
(C) a back grinding process for grinding the wafer back surface and dividing it into chips;
(D) A step of bonding an adhesive layer of the wafer processing tape to the back surface of the wafer divided into the chips while the wafer is heated;
(E) peeling the surface protection tape from the wafer surface divided into the chips;
(F) Expanding the wafer processing tape to divide the adhesive layer for each chip and to obtain a plurality of chips with the adhesive layer;
(G) in the expanded wafer processing tape, removing the slack generated in the expanding step by heating and shrinking a portion that does not overlap the chip, and maintaining the interval between the chips;
(H) picking up the chip with the adhesive layer from the adhesive layer of the wafer processing tape;
A method of manufacturing a semiconductor device including:

<How to use>
A method of using the tape when the wafer processing tape 10 of the present invention is applied to the semiconductor device manufacturing method (A) will be described with reference to FIGS. First, as shown in FIG. 3, a surface protection tape 14 for protecting a circuit pattern containing an ultraviolet curable component in an adhesive is bonded to the surface of a semiconductor wafer W on which a circuit pattern is formed, and a back grinding apparatus 15. A back grinding process for grinding the back surface of the semiconductor wafer W is performed.

  After the back grinding process is finished, as shown in FIG. 4, the semiconductor wafer W is placed on the heater table 25 of the wafer mounter with the front side facing down, and then the wafer processing tape 10 is placed on the back side of the semiconductor wafer W. Paste. In the wafer processing tape 10 used here, the adhesive layer 12 is exposed around the area where the adhesive layer 13 is exposed on the surface to be bonded to the semiconductor wafer W. The portion of the wafer processing tape 10 where the adhesive layer 13 is exposed and the back surface of the wafer W are bonded together, and the portion where the adhesive layer 12 around the adhesive layer 13 is exposed and the ring frame 20 are bonded together. At this time, the heater table 25 is set to 40 to 100 ° C., and thus heat bonding is performed.

Next, the semiconductor wafer W bonded with the wafer processing tape 10 is unloaded from the heater table 25 and placed on the suction table 26 with the wafer processing tape 10 side down as shown in FIG. . Then, from the upper side of the semiconductor wafer W sucked and fixed to the suction table 26, using the energy beam light source 27, for example, 1000 mJ / cm ² of ultraviolet light is irradiated to the substrate surface side of the surface protective tape 14, and the surface protective tape 14. The adhesive strength to the semiconductor wafer W is reduced, and the surface protection tape 14 is peeled from the surface of the semiconductor wafer W.

  Next, as shown in FIG. 6, a laser beam is irradiated on a portion to be divided of the semiconductor wafer W to form 32 modified regions by multiphoton absorption inside the semiconductor wafer W.

  Next, as shown in FIG. 7A, the wafer processing tape 10 to which the semiconductor wafer W and the ring frame 20 are bonded is placed on the stage 21 of the expanding apparatus with the base film 11 side facing down. To do.

  Next, as shown in FIG. 6B, in the state where the ring frame 20 is fixed, the hollow cylindrical push-up member 22 of the expanding apparatus is raised, and the wafer processing tape 10 is expanded (expanded). As expansion conditions, the expanding speed is, for example, 5 to 500 mm / sec, and the expanding amount (push-up amount) is, for example, 5 to 25 mm. As described above, the wafer processing tape 10 is stretched in the radial direction of the semiconductor wafer W, whereby the semiconductor wafer W is divided into units of semiconductor chips 34 starting from the modified region 32. At this time, the adhesive layer 13 is not stretched by the expansion (deformation) due to the expansion at the portion bonded to the back surface of the semiconductor wafer W, but does not break. Breaks in a concentrated manner. Therefore, as shown in FIG. 7C, the adhesive layer 13 is also cut off together with the semiconductor wafer W. Thereby, the several semiconductor chip 34 with the adhesive bond layer 13 can be obtained.

  Next, as shown in FIG. 8, the push-up member 22 is returned to its original position, and the slack of the wafer processing tape 10 generated in the previous expanding process is removed, so that the interval between the semiconductor chips 34 is stably maintained. The process is performed. In this step, for example, a temperature of 90 to 120 ° C. is used by using a hot air nozzle 29 in an annular heating / shrinking region 28 between the region 10 where the semiconductor chip 34 exists in the wafer processing tape 10 and the ring frame 20. The substrate film 11 is heated and shrunk by applying air to tension the wafer processing tape 10. This step is not essential and may be performed only when looseness of the wafer processing tape 10 becomes a problem. Thereafter, the adhesive layer 12 is subjected to an energy ray curing process or a thermosetting process to weaken the adhesive force of the adhesive layer 12 to the adhesive layer 13, and then the semiconductor chip 34 is picked up.

  Next, examples of the present invention will be described, but the present invention is not limited to these examples.

[Production of tape for wafer processing]

(1) Formation of adhesive layer <Adhesive layer A1>
25 parts by weight of phenoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., trade name FX293), 20 parts of epoxy resin (manufactured by Mitsubishi Chemical Co., Ltd., trade name 1032H60), liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation, trade name 828) Was dissolved in a mixed solvent of toluene and ethyl acetate using 40 parts of a microcapsule type latent curing agent (trade name HX3941HP, manufactured by Asahi Kasei Electronics Co., Ltd.). This solution was subjected to a 5 μm classification treatment to remove large particle diameter, and cordierite particles having an average particle diameter of 1 μm (2MgO.2Al ₂ O ₃ .5SiO _2, specific gravity 2.4, linear expansion coefficient 1.5 × 100 parts of 10 ⁻⁶ / ° C. and a refractive index of 1.57) were added and dispersed by stirring. And after apply | coating this dispersion liquid on a separator film (PET film) using a roll coater, it dried for 10 minutes in 70 degreeC oven, and obtained 25-micrometer-thick adhesive layer A1 on the separator film.

<Adhesive layer A2>
25 parts by weight of phenoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., trade name ZX-1356-2), 25 parts of epoxy resin (manufactured by Mitsubishi Chemical Co., Ltd., trade name 1032H60), liquid epoxy resin (manufactured by Mitsubishi Chemical Corporation, 10 parts of a trade name 828) and 35 parts of a microcapsule type latent curing agent (trade name HX3941HP, manufactured by Asahi Kasei Electronics Co., Ltd.) were dissolved in a mixed solvent of toluene and ethyl acetate. Cordierite particles (2MgO.2Al ₂ O ₃ .5SiO ₂ , specific gravity 2.4, linear expansion coefficient 1.5 ×, with an average particle size of 1 μm subjected to 5 μm classification treatment to remove large particle sizes. ^107.5 / ° C, refractive index of 1.57) was added to 87.5 parts and a core-shell type impact resistance modifier (trade name KW-4426, manufactured by Mitsubishi Rayon Co., Ltd.), and dispersed by stirring. And after apply | coating this dispersion liquid on a separator film (PET film) using a roll coater, it was dried in 70 degreeC oven for 10 minutes, and 25-micrometer-thick adhesive layer A2 was obtained on the separator.

<Adhesive layer A3>
36 parts by mass of a cresol novolac type epoxy resin (manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., trade name YDCN-703, epoxy equivalent 210), and a phenol resin as a curing agent for epoxy resin (trade name: Millex XLC-LL, manufactured by Mitsui Chemicals, Inc.) , Phenol resin) 30.1 parts by mass, silane coupling agent (Nihon Unicar Co., Ltd., trade name A-1160) 2.1 parts by mass, and silane coupling agent (Nihon Unicar Co., Ltd., trade name A- 189) Composition consisting of 1.1 parts by mass and 21.2 parts by mass of silica filler (particles) (trade name Aerosil R972, average particle size 0.016 μm, specific surface area 120 m ² / g, manufactured by Nippon Aerosil Co., Ltd.) Cyclohexanone was added to the product, mixed with stirring, and then kneaded for 90 minutes using a bead mill.

  Acrylic rubber (manufactured by Nagase ChemteX Corp., trade name SG-P3, weight average molecular weight 800,000) 200 parts by mass containing 1% by mass of a monomer unit derived from glycidyl acrylate or glycidyl methacrylate and 1 as a curing accelerator -0.075 part by mass of cyanoethyl-2-phenylimidazole (manufactured by Shikoku Kasei Kogyo Co., Ltd., trade name: Curazole 2PZ-CN) was added and mixed by stirring to obtain a varnish of the adhesive composition.

  In addition, the ratio of the total amount of an epoxy resin and its hardening | curing agent with respect to resin whole quantity was 24.8 mass%, and the ratio of acrylic rubber was 75.2 mass%. Moreover, the ratio of the silica filler (particles) was 7.97 parts by mass with respect to 100 parts by mass of the resin.

  This varnish was applied on a separator film (PET film) and dried by heating at 90 ° C. for 10 minutes and 120 ° C. for 5 minutes to obtain an adhesive layer A3 having a thickness of 40 μm on the separator film.

(2) Production of adhesive film <Adhesive film B1>
For the pressure-sensitive adhesive, an acrylic copolymer using 2-ethylhexyl acrylate and methyl methacrylate as main monomers and hydroxyethyl acrylate and acrylic acid as functional group monomers was obtained by a solution polymerization method. Next, 2-isocyanatoethyl methacrylate was added so that the iodine value was 20, and an acrylic copolymer was further prepared. The prepared acrylic copolymer had a weight average molecular weight of 400,000 and a glass transition point of -38 ° C. A pressure-sensitive adhesive solution in which 10 parts by weight of a polyfunctional isocyanate crosslinking agent (trade name Coronate HL, manufactured by Nippon Polyurethane Industry Co., Ltd.) is blended with 100 parts by weight of this acrylic copolymer is prepared, and a polyolefin film (thickness: 100 μm) is prepared. The adhesive film B1 was obtained by coating and drying the adhesive so that the thickness of the adhesive when dried was 10 μm. Further, a biaxially stretched polyester film separator (thickness: 25 μm) coated with a silicone release agent was laminated on the pressure-sensitive adhesive surface and allowed to stand at room temperature for 1 week for sufficient aging.

<Adhesive film B2>
For the adhesive, an acrylic copolymer using 2-ethylhexyl acrylate and methyl methacrylate as main monomers and hydroxyethyl methacrylate as a functional group monomer was obtained by a solution polymerization method. The synthesized acrylic copolymer had a weight average molecular weight of 550,000 and a glass transition point of -70 ° C. A pressure-sensitive adhesive solution containing 5 parts by weight of a polyfunctional isocyanate cross-linking agent (Sumijur N75, manufactured by Sumika Bayer Urethane Co., Ltd.) was prepared with respect to 100 parts by weight of this acrylic copolymer, and a polyolefin film (thickness: 100 μm) was prepared. The coating was dried so that the thickness of the pressure-sensitive adhesive upon drying was 10 μm, to obtain a pressure-sensitive adhesive film B2. Further, a biaxially stretched polyester film separator (thickness: 25 μm) coated with a silicone release agent was laminated on the pressure-sensitive adhesive surface and allowed to stand at room temperature for 1 week for sufficient aging.

Example 1
Return the adhesive layer A1 formed on the release film that has been refrigerated to room temperature, and adjust the adhesive layer A1 to have a cut depth of 1/2 or less of the thickness of the release film. Then, circular precut processing with a diameter of 306 mm was performed. Thereafter, unnecessary portions of the adhesive layer were removed, and the adhesive film B1 was laminated to the release film at room temperature so that the adhesive layer was in contact with the adhesive layer A1. Then, the pressure-sensitive adhesive film B1 was subjected to circular precut processing having a diameter of 370 mm concentrically with the adhesive layer by adjusting the depth of cut to be ½ or less of the thickness of the release film. A wafer processing tape was prepared.

(Examples 2 to 5, Comparative Examples 1 and 2)
Using the same adhesive layer and adhesive film of Table 1 as in Example 1, the adhesive layer was pre-cut so as to have the ratio of Table 1 for a 12-inch (300 mm diameter) semiconductor wafer. Thus, wafer processing tapes of Examples 2 to 5 and Comparative Examples 1 and 2 were produced.

(Example 6)
Using the same adhesive layer and adhesive film of Table 1 as in Example 1, the adhesive layer was pre-cut so as to have the ratio of Table 1 for a 12-inch (300 mm diameter) semiconductor wafer. did. Thereafter, the area corresponding to the wafer bonding planned portion was irradiated with 50 mJ / cm ^{2 of} UV from the adhesive film side, and the wafer processing tape of Example 6 was produced.

<Peeling force>
After laminating a semiconductor wafer to the adhesive layers of the wafer processing tapes of Examples 1 to 6 and Comparative Examples 1 and 2 with a laminator set at a heating temperature of 80 ° C., a 25 mm wide cut was made and a strip for tensile measurement was prepared. Prepared as a sample. The wafer was pressed against the stage, one end (adhesive film) of the strip sample was fixed to a tension jig of a tensile measuring machine, a 90 ° peel test was performed, and the sample was peeled off from the adhesive layer, and 90 ° at a peeling speed of 300 mm / min. The peel peel force (N / 25 mm) was measured. The results are shown in Table 1.

<Adhesiveness>
About 50 wafer processing tapes of Examples 1 to 6 and Comparative Examples 1 and 2, a bonding experiment was performed so that the adhesive layer was bonded to the semiconductor wafer under the following conditions. Observed visually, all 50 wafers that were bonded without the semiconductor wafer sticking out of the adhesive layer were marked as “◎” as excellent products. Was evaluated as “x” as a defective product. The evaluation results are shown in Table 1.
(Bonding conditions)
Pasting device: wafer mounter DAM-812M (manufactured by Takatori Co., Ltd.)
Pasting speed meter: 50mm / sec
Pasting pressure: 0.1 MPa
Pasting temperature: 80 ° C

<Contamination test of wafers by expanded cutting>
A semiconductor wafer (thickness 50 μm, diameter 300 mm) was irradiated with a laser beam to form a modified region inside the wafer. The wafer processing tapes of Examples 1 to 6 and Comparative Examples 1 and 2 were laminated to the semiconductor wafer after laser irradiation and the stainless steel ring frame. Next, with the DDS-2300 manufactured by DISCO Corporation, the ring frame bonded to the tape for wafer processing is pushed down by the expanding ring of DDS-2300 manufactured by DISCO Corporation, and the wafer bonding site outer periphery of the wafer processing tape The part that does not overlap the wafer is pressed against the circular push-up member, and the expansion is performed. The semiconductor wafer is divided along the planned cutting line from the modified region of the semiconductor wafer, and the adhesive layer is also a semiconductor. The wafer was divided at a portion corresponding to the wafer division planned line. The expanding speed was 300 mm / sec, and the expanding amount (push-up amount) was 20 mm. Thereafter, it was visually observed whether or not the adhesive layer around the wafer was broken and the fragments were scattered to contaminate the wafer surface. A product in which the adhesive layer fragments were not scattered was evaluated as “Excellent” as a good product, and a product in which the adhesive layer fragments were scattered and contaminated the wafer surface was evaluated as “x” as a defective product. The evaluation results are shown in Table 1. In Comparative Example 2, since the semiconductor wafer protruded from the adhesive layer at the time of bonding the semiconductor wafer, the contamination test of the wafer was not performed.

<Dividability test of adhesive layer by expanding>
In addition, after dividing the above expand, visually observe the dividing line, and in the state where the adhesive layer and the pressure-sensitive adhesive film are in close contact, the adhesive layer is divided into “Excellent” as an excellent product, and the adhesive A part of the layer was lifted from the dicing tape, but the part where the adhesive layer was divided was marked as “Good” and the part where the adhesive layer was not parted was regarded as a defective part. Evaluated as “x”. The evaluation results are shown in Table 1. In Comparative Example 2, since the semiconductor wafer protruded from the adhesive layer at the time of bonding the semiconductor wafer, a test for severability was not performed. Further, in Comparative Example 1, since the wafer was contaminated, the separation property was not evaluated.

<Pickup property>
After dividing the above-mentioned expand, the adhesive film was irradiated with ultraviolet rays at 200 mJ / cm ² as necessary to cure the adhesive layer of the adhesive film and reduce the adhesive strength. Then, about 100 divided | segmented chips, it picked up using the die picker apparatus (The Canon Machinery company make, brand name CAP-300II). The success rate of pick-up was determined as the success of the chip with the adhesive layer attached to the adhesive layer, which was successfully picked up. A product with a success rate of 100% was evaluated as “◎” as a good product, a product with 95% or more and less than 100% was evaluated as “Good”, and a product with 90% or more and less than 95% was evaluated as “△” as an acceptable product. . The results are shown in Table 1. In Comparative Example 2, the pick-up property was not evaluated because the semiconductor wafer protruded from the adhesive layer when the semiconductor wafer was bonded. Further, in Comparative Example 1, since the wafer was contaminated, the pickup property was not evaluated.

As shown in Table 1, in the wafer processing tape according to the example, the diameter of the adhesive layer is 1.01 to 1.06 times the diameter of the semiconductor wafer. Good results were obtained in all of the contamination of the adhesive and the breakability of the adhesive layer. Furthermore, in the wafer processing tapes according to Examples 1 to 5, the peel force between the adhesive layer and the pressure-sensitive adhesive film is 0.45 N / 25 mm or higher, which is higher than 0.4 N / 25 mm defined in claim 2. Also, the pick-up property of the semiconductor chip was excellent.
In the wafer processing tape according to Example 6, the peeling force between the adhesive layer and the pressure-sensitive adhesive film is lower than 0.4 N / 25 mm as defined in claim 2, and therefore a part of the adhesive layer is made of dicing tape. There is a possibility that the chip is damaged due to the floating state, that is, the chip is warped. In addition, because UV rays were applied while part of the adhesive layer was lifted from the dicing tape, the floating part was inhibited from curing by oxygen in the air, resulting in insufficient decrease in adhesive strength, but successful pickup. The rate was an acceptable range of 90% or more and less than 95%.

  On the other hand, the wafer processing tape according to Comparative Example 1 has a diameter of the adhesive layer exceeding 1.06 times the diameter of the semiconductor wafer, so that the adhesive layer around the semiconductor wafer breaks when expanding. The fragments were scattered and the semiconductor wafer was contaminated. In addition, the wafer processing tape according to Comparative Example 2 had a diameter of the adhesive layer lower than 1.01 times the diameter of the semiconductor wafer, so that the semiconductor wafer protruded from the adhesive layer when the semiconductor wafer was bonded.

10: Wafer processing tape 11: Base film 12: Adhesive layer 13: Adhesive layer 15: Adhesive film

Claims (5)

An adhesive film in which an adhesive layer is provided directly or indirectly on a base film;
An adhesive layer directly or indirectly formed on the adhesive film, and a wafer processing tape used for processing a semiconductor wafer,
The wafer processing tape, wherein a diameter of the adhesive layer is 1.01 to 1.06 times a diameter of the semiconductor wafer.   2. The wafer processing tape according to claim 1, wherein a peeling force between the adhesive layer and the adhesive film is 0.4 to 2.0 N / 25 mm. 3. The wafer processing tape according to claim 1, wherein the tape is used in a method for manufacturing a semiconductor device including at least the following steps in random order.
(A) A step of bonding the adhesive layer to the back surface of the semiconductor wafer while the semiconductor wafer is heated;
(B) a step of forming a dividing line with a laser beam or a blade at a part to be divided of the semiconductor wafer;
(C) dividing the semiconductor wafer and the adhesive layer along a dividing line by expanding the adhesive film, and obtaining a plurality of semiconductor chips with the adhesive layer;
(D) Step of picking up the semiconductor chip with the adhesive layer from the pressure-sensitive adhesive layer 3. The wafer processing tape according to claim 1, wherein the tape is used in a method for manufacturing a semiconductor device including at least the following steps in random order.
(A) A step of bonding the adhesive layer to the back surface of the semiconductor wafer while the semiconductor wafer is heated;
(B) a step of forming a modified region by multiphoton absorption inside the wafer by irradiating a laser beam with a focused light inside the portion to be divided of the semiconductor wafer;
(C) a step of dividing the semiconductor wafer and the adhesive layer along the planned cutting portion by expanding the adhesive film to obtain a plurality of semiconductor chips with the adhesive layer;
(D) Step of picking up the semiconductor chip with the adhesive layer from the pressure-sensitive adhesive layer 3. The wafer processing tape according to claim 1, wherein the tape is used in a method for manufacturing a semiconductor device including at least the following steps in random order.
(A) cutting the semiconductor wafer to a depth less than the thickness of the wafer along a line to be cut using a laser beam or a dicing blade;
(B) a step of bonding a surface protection tape to the surface of the semiconductor wafer;
(C) a back grinding process for dividing the semiconductor wafer into the semiconductor chips by grinding the back surface of the semiconductor wafer;
(D) A step of bonding the adhesive layer to the back surface of the wafer divided into the semiconductor chips while the semiconductor wafer is heated;
(E) peeling the semiconductor surface protective tape from the surface of the semiconductor wafer divided into the semiconductor chips;
(F) dividing the adhesive layer in correspondence with the semiconductor chip by expanding the adhesive film to obtain a plurality of semiconductor chips with the adhesive layer;
(G) A step of picking up the semiconductor chip with the adhesive layer from the pressure-sensitive adhesive layer

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