JP7129375B2 - Semiconductor processing tape - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention can be used to fix a wafer in a dicing process for dividing a wafer into chip-shaped elements, and a die bonding process for bonding between chips after dicing or between a chip and a substrate. The present invention relates to an expandable tape for semiconductor processing, which can be used not only in the mounting process but also in the process of dividing an adhesive layer along chips by expansion.

Conventionally, in the manufacturing process of semiconductor devices such as integrated circuits (IC: Integrated Circuit), a back grinding process of grinding the back surface of the wafer in order to thin the wafer after circuit pattern formation, adhesiveness and stretchability on the back surface of the wafer. After affixing a certain semiconductor processing tape, the dicing process divides the wafer into chips, the expansion process expands the semiconductor processing tape, the pick-up process picks up the cut chips, and the picked-up chips A die-bonding (mounting) process is carried out for bonding to a lead frame, a package substrate, or the like (or stacking and bonding chips together in a stacked package).

In the back grinding process, a surface protection tape is used to protect the circuit pattern forming surface of the wafer (wafer surface) from contamination. When removing the surface protective tape from the wafer surface after grinding the back surface of the wafer, a semiconductor processing tape (dicing/die bonding tape) described below is attached to the back surface of the wafer, and then a semiconductor processing tape is attached to the suction table. After the tape side is fixed and the surface protection tape is treated to reduce the adhesive force to the wafer, the surface protection tape is peeled off. The wafer from which the surface protection tape has been peeled off is then picked up from the suction table with the wafer bonded to its back surface, and is subjected to the next dicing process. In addition, the above-mentioned treatment to reduce the adhesive strength is energy ray irradiation treatment when the surface protection tape is composed of an energy ray curable component such as ultraviolet rays, and when the surface protection tape is composed of a thermosetting component, heat treatment.

In the dicing process to the mounting process after the back grinding process, a semiconductor processing tape is used in which an adhesive layer and an adhesive layer are laminated in this order on a substrate film. In general, when using such a tape for semiconductor processing, first, an adhesive layer of the tape for semiconductor processing is adhered to the back surface of the wafer to fix the wafer, and the wafer and the adhesive layer are separated into chips using a dicing blade. Dice into units. After that, an expanding step is performed to widen the gap between the chips by expanding the tape in the radial direction of the wafer. This expanding process is carried out in the subsequent pick-up process in order to improve the recognizability of the chip by a CCD camera or the like and to prevent damage to the chip caused by contact between adjacent chips when picking up the chip. be. After that, the chip is picked up by being separated from the adhesive layer together with the adhesive layer in the pickup process, and directly adhered to a lead frame, a package substrate, or the like in the mounting process. In this way, by using a semiconductor processing tape, it is possible to directly bond a chip with an adhesive layer to a lead frame, a package substrate, or the like. The step of adhering the film can be omitted.

However, in the dicing process, as described above, the wafer and the adhesive layer are diced together using a dicing blade, so that not only cutting debris from the wafer but also cutting debris from the adhesive layer are generated. If the dicing grooves of the wafer are clogged with chips from the adhesive layer, the chips stick to each other, resulting in pick-up failures and the like, resulting in a decrease in the manufacturing yield of semiconductor devices.

In order to solve such problems, a method has been proposed in which only the wafer is diced with a blade in the dicing process, and the adhesive layer is divided into individual chips by expanding the semiconductor processing tape in the expanding process. (for example, Patent Document 1). According to such a method of dividing the adhesive layer using the tension during expansion, scraps of the adhesive are not generated and there is no adverse effect on the pick-up process.

In recent years, as a wafer cutting method, a so-called stealth dicing method has been proposed, in which a laser processing apparatus is used to cut a wafer in a non-contact manner. For example, in Patent Document 2, as a stealth dicing method, an adhesive layer (die-bonding resin layer) is interposed to focus light on the inside of a semiconductor substrate to which a sheet is pasted, and a laser beam is irradiated. A step of forming a modified region inside a semiconductor substrate by multiphoton absorption and using this modified region as a cutting target portion, and expanding a sheet to cut the semiconductor substrate and the adhesive layer along the cutting target portion. A method for cutting a semiconductor substrate is disclosed, comprising the steps of:

Further, as another wafer cutting method using a laser processing apparatus, for example, Patent Document 3 discloses a step of attaching an adhesive layer (adhesive film) for die bonding to the back surface of the wafer, and A step of attaching an extensible protective adhesive tape to the adhesive layer side of the attached wafer, and irradiating a laser beam along the streets from the surface of the wafer to which the protective adhesive tape is attached to individual chips. A step of dividing, a step of extending the protective adhesive tape to apply a tensile force to the adhesive layer to break the adhesive layer for each chip, and a step of protecting the chip to which the broken adhesive layer is attached. A wafer division method has been proposed that includes a step of separating the wafer from the tape.

According to the wafer cutting methods described in Patent Documents 2 and 3, the wafer is cut in a non-contact manner by irradiating the laser beam and expanding the tape. It is possible to cut the wafer without generating chipping of the wafer as in the case of blade dicing. In addition, since the adhesive layer is divided by expansion, cutting chips of the adhesive layer are not generated. Therefore, it is attracting attention as an excellent technique that can replace blade dicing.

However, as described in the above Patent Documents 1 to 3, in the method of expanding by expanding and dividing the adhesive layer, when using a conventional semiconductor processing tape, the expanding amount increases and the expanding ring There is a problem in that the portion pushed up by the expansion is stretched, the portion becomes loose after unexpanded, and the interval between chips (hereinafter referred to as "kerf width") cannot be maintained.

Therefore, a method has been proposed in which the adhesive layer is divided by expansion, and after the expansion is released, the slack portion of the tape for semiconductor processing is heated to be shrunk to maintain the kerf width (for example, Patent Document 4). , 5).

JP-A-2007-5530 JP-A-2003-338467 JP 2004-273895 A WO2016/152957 JP 2015-211081 A

By the way, as a method for shrinking the slack of the semiconductor processing tape caused by the expansion by heating, generally, a pair of hot air nozzles are circulated around the annular portion where the slack is caused by being pushed up by the expanding ring. A method of heating and shrinking by applying hot air to the part is used.

In the tape for semiconductor processing described in Patent Document 4, the thermal contraction rate in both the longitudinal direction and the width direction of the tape when heated at 100° C. for 10 seconds is 0% or more and 20% or less. However, when the hot air nozzle is circulated for heating, the temperature in the vicinity of the surface of the tape for semiconductor processing gradually rises, so there is the problem that it takes time to remove the slack in all of the annular portions. was there. In addition, if the kerf width is narrow, it becomes difficult to distinguish the boundary line between adjacent chips, which causes erroneous chip recognition during image recognition during pickup, resulting in a decrease in yield in the semiconductor component manufacturing process.

In addition, the semiconductor processing tape described in Patent Document 5 has a shrinkage rate of 0.1% or more at 130 ° C. to 160 ° C. (see claim 1 of Patent Document 5). the temperature is high. Therefore, when performing heat shrinkage with hot air, a high temperature and a long heating time are required, and the hot air may affect the adhesive layer near the outer periphery of the wafer, causing the split adhesive layer to melt and re-bond. There is In addition, if the kerf width is narrow, it becomes difficult to distinguish the boundary line between adjacent chips, which causes erroneous chip recognition during image recognition during pickup, resulting in a decrease in yield in the semiconductor component manufacturing process.

Therefore, according to the present invention, the kerf width is sufficiently set to the extent that heat shrinkage can be performed sufficiently in a short time, the boundary between adjacent chips can be easily distinguished, and misrecognition of chips in image recognition during picking up can be suppressed. An object of the present invention is to provide a semiconductor processing tape that can be held.

In order to solve the above problems, a semiconductor processing tape according to the present invention has an adhesive tape having a base film and an adhesive layer formed on at least one surface side of the base film, and the adhesive tape is the average value of the differential value of the thermal deformation rate every 1 ° C between 40 ° C and 80 ° C measured by the thermo-mechanical property tester in the MD direction, and the temperature rise by the thermo-mechanical property tester in the TD direction It is characterized in that the sum of the average value and the average value of the differential values of the thermal deformation rate measured every 1° C. between 40° C. and 80° C. is a negative value.

Further, in the semiconductor processing tape, it is preferable that an adhesive layer and a release film are laminated in this order on the adhesive layer side.

The semiconductor processing tape is preferably used for full-cut and half-cut blade dicing, full-cut laser dicing, or laser stealth dicing.

According to the semiconductor processing tape according to the present invention, it is possible to sufficiently heat and shrink in a short time, to make it easy to distinguish the boundary between adjacent chips, and to suppress misrecognition of chips in image recognition at the time of picking up. A sufficient kerf width can be maintained.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing which shows typically the structure of the tape for semiconductor processing which concerns on embodiment of this invention. FIG. 4 is a cross-sectional view showing a state in which a surface protection tape is attached to a wafer; FIG. 4 is a cross-sectional view for explaining a step of bonding a wafer and a ring frame to the semiconductor processing tape according to the embodiment of the present invention; It is sectional drawing explaining the process of peeling a surface protection tape from the surface of a wafer. FIG. 4 is a cross-sectional view showing a state in which a modified region is formed on a wafer by laser processing; (a) It is sectional drawing which shows the state in which the tape for semiconductor processing which concerns on embodiment of this invention was mounted in the expanding apparatus. (b) is a cross-sectional view showing a process of dividing the wafer into chips by expanding the semiconductor processing tape; (c) A cross-sectional view showing the semiconductor processing tape, the adhesive layer, and the chip after expansion. It is a sectional view for explaining a heat contraction process. FIG. 4 is an explanatory diagram showing kerf width measurement points in evaluation of Examples and Comparative Examples. It is an example of a measurement result of a thermal deformation rate.

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below.

FIG. 1 is a cross-sectional view showing a semiconductor processing tape 10 according to an embodiment of the present invention. In the semiconductor processing tape 10 of the present invention, the adhesive layer 13 is split along the chips when the wafer is split into chips by expansion. This semiconductor processing tape 10 has an adhesive tape 15 composed of a base film 11 and an adhesive layer 12 provided on the base film 11, and an adhesive layer 13 provided on the adhesive layer 12. Then, the back surface of the wafer is bonded onto the adhesive layer 13 . In addition, each layer may be cut (pre-cut) into a predetermined shape in advance according to the process and equipment used. Furthermore, the semiconductor processing tape 10 of the present invention may be in the form of being cut for each wafer, or a long sheet formed by cutting each wafer for each sheet, It may be in a form wound into a roll. The configuration of each layer will be described below.

<Base film>
The base film 11 preferably has uniform and isotropic extensibility in that the wafer can be cut evenly in all directions in the expanding step, and the material thereof is not particularly limited. In general, a crosslinked resin has a greater restoring force against tension than a non-crosslinked resin, and has a greater shrinkage stress when heat is applied to the stretched state after the expansion step. Therefore, it is excellent in that the slack generated in the tape after the expanding step is removed by heat shrinkage, and the tape is tensed to stably maintain the interval (kerf width) between individual chips. Among crosslinked resins, thermoplastic crosslinked resins are more preferably used. On the other hand, non-crosslinked resins have a smaller restoring force against tension than crosslinked resins. Therefore, after the expansion process in a low temperature range such as -15°C to 0°C, the tape is once relaxed and returned to room temperature, so that the tape does not shrink easily when heading to the pick-up process and the mounting process, so that it adheres to the chip. It is excellent in that it can prevent the adhesive layers from coming into contact with each other. Among non-crosslinked resins, olefinic non-crosslinked resins are more preferably used.

Examples of such thermoplastic crosslinked resins include, for example, ethylene-(meth)acrylic acid binary copolymers or ethylene-(meth)acrylic acid-(meth)acrylic acid alkyl esters as main polymer constituents. Ionomer resins obtained by cross-linking the original copolymer with metal ions are exemplified. These are particularly suitable in that they are suitable for the expanding process in terms of uniform expansibility, and that their crosslinking exerts a strong restoring force when heated. The metal ions contained in the ionomer resin are not particularly limited, and examples thereof include zinc and sodium. Zinc ions are preferred from the viewpoint of low elution and low contamination. In the (meth)acrylic acid alkyl ester of the terpolymer, the alkyl group having 1 to 4 carbon atoms preferably has a high elastic modulus and can transmit a strong force to the wafer. Examples of such (meth)acrylic acid alkyl esters include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate. mentioned.

In addition to the above ionomer resins, the above-mentioned thermoplastic crosslinked resins include low-density polyethylene having a specific gravity of 0.910 or more and less than 0.930, ultra-low-density polyethylene having a specific gravity of less than 0.910, and ethylene-acetic acid. A resin selected from vinyl copolymers and crosslinked by irradiation with energy rays such as electron beams is also suitable. Such a thermoplastic crosslinked resin has a certain uniform extensibility because crosslinked sites and non-crosslinked sites coexist in the resin. In addition, since a strong restoring force acts when heated, it is also suitable for removing slack in the tape that occurred during the expansion process. Even if it is incinerated, it does not generate chlorinated aromatic hydrocarbons such as dioxins and their analogues, so the environmental load is small. By appropriately adjusting the amount of energy rays with which the polyethylene or ethylene-vinyl acetate copolymer is irradiated, a resin having sufficient uniform extensibility can be obtained.

Examples of non-crosslinked resins include mixed resin compositions of polypropylene and styrene-butadiene copolymer.

As the polypropylene, for example, a propylene homopolymer or a block-type or random-type propylene-ethylene copolymer can be used. A random type propylene-ethylene copolymer is preferred because of its low rigidity. When the content of the ethylene structural unit in the propylene-ethylene copolymer is 0.1% by weight or more, the rigidity of the tape and the compatibility between the resins in the mixed resin composition are excellent. When the rigidity of the tape is appropriate, the cuttability of the wafer is improved, and when the compatibility between the resins is high, the extrusion discharge rate is easily stabilized. More preferably, it is 1% by weight or more. Also, when the content of the ethylene structural unit in the propylene-ethylene copolymer is 7% by weight or less, it is excellent in that the polypropylene is stably polymerized easily. More preferably, it is 5% by weight or less.

A hydrogenated one may be used as the styrene-butadiene copolymer. When the styrene-butadiene copolymer is hydrogenated, it has good compatibility with propylene and can prevent embrittlement and discoloration due to oxidative degradation caused by double bonds in butadiene. Further, when the content of the styrene structural unit in the styrene-butadiene copolymer is 5% by weight or more, the styrene-butadiene copolymer is stable and easy to polymerize, which is preferable. Moreover, when the content is 40% by weight or less, flexibility and extensibility are excellent. It is more preferably 25% by weight or less, still more preferably 15% by weight or less. As the styrene-butadiene copolymer, either a block type copolymer or a random type copolymer can be used. A random type copolymer is preferable because the styrene phase is uniformly dispersed, the stiffness can be prevented from becoming too large, and the expandability is improved.

When the content of polypropylene in the mixed resin composition is 30% by weight or more, it is excellent in that unevenness in the thickness of the base film can be suppressed. If the thickness is uniform, the expandability tends to be isotropic, and the stress relaxation property of the base film becomes too large, the distance between chips decreases over time, and the adhesive layers come into contact with each other and remelt. Easy to prevent wearing. More preferably, it is 50% by weight or more. Moreover, when the polypropylene content is 90% by weight or less, it is easy to appropriately adjust the rigidity of the base film. If the rigidity of the base film becomes too high, the force required to expand the base film increases, which increases the load on the device, and the wafer and the adhesive layer 13 cannot be expanded sufficiently to divide. , so it is important to adjust accordingly. The lower limit of the content of the styrene-butadiene copolymer in the composite resin composition is preferably 10% by weight or more, and it is easy to adjust the rigidity of the base film suitable for the device. When the upper limit is 70% by weight or less, it is excellent in that thickness unevenness can be suppressed, and 50% by weight or less is more preferable.

Although the substrate film 11 is a single layer in the example shown in FIG. Two or more layers may be laminated. Two or more kinds of resins are preferable from the viewpoint that each characteristic is further enhanced if crosslinkable or non-crosslinkable is unified, and when laminating a combination of crosslinkable or non-crosslinkable, each It is preferable because it compensates for the shortcomings. The thickness of the base film 11 is not particularly specified, but it is sufficient that the base film 11 is easily stretched in the step of expanding the semiconductor processing tape 10 and has sufficient strength to prevent breakage. For example, about 50 to 300 μm is preferable, and 70 to 200 μm is more preferable.

As a method for manufacturing the multilayer base film 11, a conventionally known extrusion method, lamination method, or the like can be used. When using the lamination method, an adhesive may be interposed between the layers. Conventionally known adhesives can be used as the adhesive.

<Adhesive layer>
The adhesive layer 12 can be formed by applying an adhesive composition to the base film 11 . The adhesive layer 12 constituting the semiconductor processing tape 10 of the present invention does not separate from the adhesive layer 13 during dicing, and has a holding property to the extent that defects such as chip flying do not occur. Any material may be used as long as it has the property of being easily separated from the layer 13 .

In the semiconductor processing tape 10 of the present invention, the configuration of the adhesive composition constituting the adhesive layer 12 is not particularly limited, but in order to improve the pick-up property after dicing, the energy ray-curable one is preferable, and the cured adhesive composition is preferably cured. A material that can be easily separated from the adhesive layer 13 later is preferable. In one embodiment, the pressure-sensitive adhesive composition contains 60 mol% or more of a (meth)acrylate having an alkyl chain having 6 to 12 carbon atoms as a base resin, and has an iodine value of 5 to 30 and is energy ray-curable. Those having a polymer (A) having a carbon-carbon double bond are exemplified. Here, the energy ray means a ray such as an ultraviolet ray or an ionizing radiation such as an electron beam.

In such a polymer (A), when the amount of the energy ray-curable carbon-carbon double bond introduced is 5 or more in terms of iodine value, the effect of reducing the adhesive force after energy ray irradiation is enhanced. More preferably 10 or more. Further, when the iodine value is 30 or less, the holding power of the chip after the energy beam irradiation until it is picked up is high, and it is excellent in that the gap between the chips can be easily widened at the time of expansion immediately before the picking up step. It is preferable to widen the gap between the chips sufficiently before the pick-up process, because it facilitates image recognition of each chip at the time of pick-up and facilitates pick-up. Further, when the amount of carbon-carbon double bonds introduced is 5 or more and 30 or less in terms of iodine value, the polymer (A) itself has stability and production becomes easy, which is preferable.

Furthermore, when the glass transition temperature of the polymer (A) is −70° C. or higher, it is excellent in terms of heat resistance against heat accompanying energy ray irradiation, and more preferably −66° C. or higher. If the temperature is 15° C. or lower, the effect of preventing chip scattering after dicing from a wafer with a rough surface is excellent, and the temperature is more preferably 0° C. or lower, further preferably −28° C. or lower.

The above polymer (A) may be produced by any method. , an acrylic copolymer having a functional group or a methacrylic copolymer having a functional group (A1), and a functional group capable of reacting with the functional group, and an energy ray-curable carbon-carbon double bond is obtained by reacting the compound (A2) having

Among these, the methacrylic copolymer (A1) having the above functional group includes a monomer (A1-1) having a carbon-carbon double bond such as alkyl acrylate or alkyl methacrylate, and carbon Examples include those obtained by copolymerizing a monomer (A1-2) having a -carbon double bond and a functional group. The monomer (A1-1) includes hexyl acrylate, n-octyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, decyl acrylate, lauryl acrylate, or an alkyl chain having an alkyl chain having 6 to 12 carbon atoms. pentyl acrylate, n-butyl acrylate, isobutyl acrylate, ethyl acrylate, methyl acrylate, or similar methacrylates, which are monomers having 5 or less carbon atoms.

A component having an alkyl chain with 6 or more carbon atoms in the monomer (A1-1) can reduce the peeling force between the pressure-sensitive adhesive layer and the adhesive layer, and is therefore excellent in pick-up property. Further, a component having a value of 12 or less has a low elastic modulus at room temperature, and is excellent in adhesive strength at the interface between the pressure-sensitive adhesive layer and the adhesive layer. If the adhesive strength at the interface between the adhesive layer and the adhesive layer is high, when the tape is expanded and the wafer is cut, the interface displacement between the adhesive layer and the adhesive layer can be suppressed, and the cutting performance is improved. Therefore, it is preferable.

Furthermore, as the monomer (A1-1), the glass transition temperature decreases as the number of carbon atoms in the alkyl chain increases. can be prepared. In addition to the glass transition temperature, it is also possible to blend a low-molecular-weight compound having a carbon-carbon double bond such as vinyl acetate, styrene, acrylonitrile, etc. for the purpose of increasing various performances such as compatibility. In that case, these low-molecular-weight compounds should be blended within the range of 5 mass % or less of the total mass of the monomer (A1-1).

On the other hand, the functional group possessed by the monomer (A1-2) includes a carboxyl group, a hydroxyl group, an amino group, a cyclic acid anhydride group, an epoxy group, an isocyanate group and the like. Specific examples include acrylic acid, methacrylic acid, cinnamic acid, itaconic acid, fumaric acid, phthalic acid, 2-hydroxyalkyl acrylates, 2-hydroxyalkyl methacrylates, glycol monoacrylates, glycol monomethacrylates, N -methylol acrylamide, N-methylol methacrylamide, allyl alcohol, N-alkylaminoethyl acrylates, N-alkylaminoethyl methacrylates, acrylamides, methacrylamides, maleic anhydride, itaconic anhydride, fumaric anhydride, phthalic anhydride Mention may be made of acids, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, and the like.

Further, in the compound (A2), examples of the functional group used include a hydroxyl group, an epoxy group, an isocyanate group, etc. when the functional group possessed by the compound (A1) is a carboxyl group or a cyclic acid anhydride group. If it is a hydroxyl group, it may include a cyclic acid anhydride group, an isocyanate group, and the like. If it is an amino group, it may include an epoxy group, an isocyanate group, and the like. , a carboxyl group, a cyclic acid anhydride group, an amino group and the like, and specific examples thereof include those listed in the specific examples of the monomer (A1-2). As the compound (A2), a polyisocyanate compound in which part of the isocyanate groups are urethanized with a monomer having a hydroxyl group or a carboxyl group and an energy ray-curable carbon-carbon double bond can also be used.

By leaving unreacted functional groups in the reaction of compound (A1) and compound (A2), desired properties such as acid value or hydroxyl value can be produced. If the OH group is left in such a manner that the hydroxyl value of the polymer (A) is 5 to 100, the adhesive strength after energy ray irradiation is reduced, thereby further reducing the risk of pick-up errors. In addition, when the COOH group is left so that the acid value of the polymer (A) is 0.5 to 30, an improvement effect after restoration of the pressure-sensitive adhesive layer after expanding the tape for semiconductor processing of the present invention can be obtained. preferred. When the hydroxyl value of the polymer (A) is 5 or more, the effect of reducing the adhesive strength after energy ray irradiation is excellent, and when it is 100 or less, the fluidity of the pressure-sensitive adhesive after energy ray irradiation is excellent. . When the acid value is 0.5 or more, the tape is excellent in restoring properties, and when it is 30 or less, the fluidity of the pressure-sensitive adhesive is excellent.

In the synthesis of the above polymer (A), when the reaction is carried out by solution polymerization, ketone-based, ester-based, alcohol-based and aromatic-based organic solvents can be used. Among them, toluene and acetic acid Ethyl, isopropyl alcohol, benzene methyl cellosolve, ethyl cellosolve, acetone, methyl ethyl ketone, etc. are generally good solvents for acrylic polymers, preferably solvents with a boiling point of 60 to 120 ° C. As a polymerization initiator, α,α'-azobis Azobis-based radical generators such as isobutylnitrile and organic peroxide-based radical generators such as benzoyl peroxide are usually used. At this time, a catalyst and a polymerization inhibitor can be used in combination as necessary, and a polymer (A) having a desired molecular weight can be obtained by adjusting the polymerization temperature and polymerization time. As for adjusting the molecular weight, it is preferable to use a mercaptan or carbon tetrachloride solvent. This reaction is not limited to solution polymerization, and other methods such as bulk polymerization and suspension polymerization may be used.

The polymer (A) can be obtained as described above. In the present invention, when the molecular weight of the polymer (A) is 300,000 or more, it is excellent in that the cohesive force can be increased. When the cohesive force is high, it has the effect of suppressing the displacement at the interface with the adhesive layer during expansion, and the tensile force is easily propagated to the adhesive layer, so the splittability of the adhesive layer is improved. is preferred. When the molecular weight of the polymer (A) is 2,000,000 or less, it is excellent in suppressing gelation during synthesis and coating. In addition, the molecular weight in the present invention is a weight average molecular weight in terms of polystyrene.

In addition, in the semiconductor processing tape 10 of the present invention, the resin composition constituting the adhesive layer 12 may further contain a compound (B) acting as a cross-linking agent in addition to the polymer (A). good. Examples thereof include polyisocyanates, melamine-formaldehyde resins, and epoxy resins, and these can be used alone or in combination of two or more. This compound (B) reacts with the polymer (A) or the base film, and the crosslinked structure formed as a result of the reaction causes the pressure-sensitive adhesive composition containing the polymers (A) and (B) as main components to be formed after the pressure-sensitive adhesive composition is applied. can improve the cohesion of

Polyisocyanates are not particularly limited, and examples include 4,4'-diphenylmethane diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenyl ether diisocyanate, 4,4'-[2,2-bis(4 -phenoxyphenyl)propane] diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethyl-hexamethylene diisocyanate, isophorone diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 2,4'-dicyclohexylmethane diisocyanate , lysine diisocyanate, lysine triisocyanate, etc. Specifically, Coronate L (manufactured by Nippon Polyurethane Co., Ltd., trade name) and the like can be used. Specific examples of melamine/formaldehyde resins that can be used include Nicalac MX-45 (manufactured by Sanwa Chemical Co., Ltd., trade name) and Melan (manufactured by Hitachi Chemical Co., Ltd., trade name). As the epoxy resin, TETRAD-X (manufactured by Mitsubishi Chemical Corporation, trade name) or the like can be used. In the present invention, it is particularly preferred to use polyisocyanates.

A pressure-sensitive adhesive layer in which the amount of the compound (B) added is 0.1 parts by mass or more per 100 parts by mass of the polymer (A) is excellent in terms of cohesion. More preferably, it is 0.5 parts by mass or more. In addition, the pressure-sensitive adhesive layer containing 10 parts by mass or less is excellent in suppressing rapid gelation during coating, and workability such as blending and coating of the pressure-sensitive adhesive is improved. More preferably, it is 5 parts by mass or less.

Moreover, in the present invention, the adhesive layer 12 may contain a photopolymerization initiator (C). The photopolymerization initiator (C) contained in the adhesive layer 12 is not particularly limited, and conventionally known ones can be used. For example, benzophenones such as benzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-diethylaminobenzophenone and 4,4'-dichlorobenzophenone, acetophenones such as acetophenone and diethoxyacetophenone, 2-ethylanthraquinone, t- Anthraquinones such as butyl anthraquinone, 2-chlorothioxanthone, benzoin ethyl ether, benzoin isopropyl ether, benzyl, 2,4,5-triarylimidazole dimer (lophine dimer), acridine compounds and the like. These can be used alone or in combination of two or more. The amount of the photopolymerization initiator (C) added is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, per 100 parts by mass of the polymer (A). Moreover, the upper limit is preferably 10 parts by mass or less, more preferably 5 parts by mass or less.

Further, the energy ray-curable pressure-sensitive adhesive used in the present invention may optionally contain tackifiers, pressure-sensitive adhesive modifiers, surfactants, or other modifiers. Moreover, you may add an inorganic compound filler suitably.

The adhesive layer 12 can be formed using a conventional method for forming an adhesive layer. For example, a method of applying the pressure-sensitive adhesive composition to a predetermined surface of the base film 11 to form it, or a method of applying the pressure-sensitive adhesive composition to a separator (for example, a plastic film or sheet coated with a release agent) ) to form an adhesive layer 12, and then the adhesive layer 12 can be formed on the substrate film 11 by a method of transferring the adhesive layer 12 to a predetermined surface of the substrate. In addition, the pressure-sensitive adhesive layer 12 may have a single layer form, or may have a laminated form.

The thickness of the pressure-sensitive adhesive layer 12 is not particularly limited. When the thickness is 15 μm or less, the pick-up property is excellent, and 10 μm or less is more preferable.

The pressure-sensitive adhesive tape 15 is measured by a thermomechanical property tester in the MD (Machine Direction) direction when the temperature is increased between 40 ° C. and 80 ° C. for each 1 ° C. between 40 ° C. and 80 ° C. The average value of the differential value of the thermal deformation rate, and the TD (Transverse Direction ) direction is a negative value, that is, less than 0, with the average value of the differential value of the thermal deformation rate measured at every 1° C. between 40° C. and 80° C. when the temperature is raised by a thermomechanical property tester. The MD direction is the flow direction during film formation, and the TD direction is the direction perpendicular to the MD direction.

The average value of the differential value of the thermal deformation rate for each 1 ° C. between 40 ° C. and 80 ° C. measured by the thermomechanical property tester in the MD direction of the adhesive tape 15 and the thermomechanical property tester in the TD direction By setting the sum of the average value of the differential value of the thermal deformation rate for each 1° C. between 40° C. and 80° C. measured during the temperature rise to a negative value, the semiconductor processing tape 10 can be formed by heating at a low temperature for a short period of time. can be contracted. Therefore, even when a pair of hot air nozzles are circulated around the slack portion of the semiconductor processing tape 10 to cause heat shrinkage, the amount of expansion is reduced and heat shrinkage is not repeated many times. , the slack caused by expansion can be removed in a short period of time, and an appropriate kerf width can be maintained.

The thermal deformation rate can be calculated from the following formula (1) by measuring the amount of deformation due to temperature in accordance with JIS K7197:2012.
Thermal deformation rate TMA (%) = (deformation amount of sample length / sample length before measurement) x 100 (1)
For the amount of deformation, the expansion direction of the sample is positive, and the contraction direction is negative.

The differential value of the thermal deformation rate becomes like the curve in the MD direction or the curve in the TD direction in FIG. 9, and the sum of the average value of the differential values in the MD direction and the average value of the differential values in the TD direction is a negative value. means that the adhesive tape generally exhibits shrinkage behavior between 40°C and 80°C.
In order to make the sum of the average value of the differential values in the MD direction and the average value of the differential values in the TD direction negative, a step of stretching the resin film after forming the film is added, and the resin constituting the adhesive tape 15 is It is preferable to adjust the thickness of the adhesive tape 15 and the amount of stretching in the MD direction or the TD direction according to the type. Methods for stretching the adhesive tape in the TD direction include a method using a tenter, a method by blow molding (inflation), and a method using an expand roll. method, a method of pulling in a conveying roll, and the like. Any method may be used to obtain the adhesive tape 15 of the present invention.

<Adhesive layer>
In the semiconductor processing tape 10 of the present invention, the adhesive layer 13 separates from the adhesive layer 12 and adheres to the chip when the chip is picked up after the wafer is bonded and diced. It is then used as an adhesive for fixing chips to substrates and lead frames.

The adhesive layer 13 is not particularly limited, but may be any film-like adhesive that is commonly used for wafers, such as those containing a thermoplastic resin and a thermopolymerizable component. . The thermoplastic resin used for the adhesive layer 13 of the present invention is preferably a resin having thermoplasticity, or a resin having thermoplasticity in an uncured state and forming a crosslinked structure after heating. One embodiment includes a thermoplastic resin having a weight average molecular weight of 5000-200,000 and a glass transition temperature of 0-150°C. Another embodiment is a thermoplastic resin having a weight average molecular weight of 100,000 to 1,000,000 and a glass transition temperature of -50 to 20°C.

Examples of the former thermoplastic resins include polyimide resins, polyamide resins, polyetherimide resins, polyamideimide resins, polyester resins, polyesterimide resins, phenoxy resins, polysulfone resins, polyethersulfone resins, polyphenylene sulfide resins, and polyetherketones. Among them, polyimide resins and phenoxy resins are preferably used. As the latter thermoplastic resin, polymers containing functional groups are preferably used.

A polyimide resin can be obtained by condensation reaction of a tetracarboxylic dianhydride and a diamine by a known method. That is, equimolar or approximately equimolar amounts of tetracarboxylic dianhydride and diamine are used in an organic solvent (the order of addition of each component is arbitrary), and the addition reaction is carried out at a reaction temperature of 80°C or lower, preferably 0 to 60°C. As the reaction progresses, the viscosity of the reaction solution gradually increases, and polyamic acid, which is a precursor of polyimide, is produced. The molecular weight of this polyamic acid can also be adjusted by heating at a temperature of 50 to 80° C. to depolymerize it. A polyimide resin can be obtained by dehydrating and ring-closing the reactant (polyamic acid). Dehydration ring closure can be carried out by a thermal ring closure method involving heat treatment and a chemical ring closure method using a dehydrating agent.

The tetracarboxylic dianhydride used as a raw material for the polyimide resin is not particularly limited, and examples include 1,2-(ethylene)bis(trimellitate anhydride), 1,3-(trimethylene)bis(trimellitate anhydride) 1,4-(tetramethylene)bis(trimellitate anhydride), 1,5-(pentamethylene)bis(trimellitate anhydride), 1,6-(hexamethylene)bis(trimellitate anhydride), 1,7-( Heptamethylene)bis(trimellitate anhydride), 1,8-(octamethylene)bis(trimellitate anhydride), 1,9-(nonamethylene)bis(trimellitate anhydride), 1,10-(decamethylene)bis(trimellitate anhydride) product), 1,12-(dodecamethylene)bis(trimellitate anhydride), 1,16-(hexadecamethylene)bis(trimellitate anhydride), 1,18-(octadecamethylene)bis(trimellitate anhydride), pyromellitic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,2′,3,3′-biphenyltetracarboxylic dianhydride, 2,2-bis(3 ,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, 1,1 -bis(3,4-dicarboxyphenyl)ethane dianhydride, bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, bis(3,4 -dicarboxyphenyl)sulfone dianhydride, 3,4,9,10-perylenetetracarboxylic acid dianhydride, bis(3,4-dicarboxyphenyl)ether dianhydride, benzene-1,2,3,4 -tetracarboxylic dianhydride, 3,4,3',4'-benzophenonetetracarboxylic dianhydride, 2,3,2',3'-benzophenonetetracarboxylic dianhydride, 3,3,3' ,4'-benzophenonetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 2,3,6, 7-naphthalenetetracarboxylic dianhydride, 1,2,4,5-naphthalenetetracarboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2, 7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,3, 6,7-tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene-1,8,9,10-tetracarboxylic dianhydride, pyrazine-2,3,5,6- Tetracarboxylic dianhydride, thiophene-2,3,5,6-tetracarboxylic dianhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride, 3,4,3',4 '-biphenyltetracarboxylic dianhydride, 2,3,2',3'-biphenyltetracarboxylic dianhydride, bis(3,4-dicarboxyphenyl)dimethylsilane dianhydride, bis(3,4- dicarboxyphenyl)methylphenylsilane dianhydride, bis(3,4-dicarboxyphenyl)diphenylsilane dianhydride, 1,4-bis(3,4-dicarboxyphenyldimethylsilyl)benzene dianhydride, 1, 3-bis(3,4-dicarboxyphenyl)-1,1,3,3-tetramethyldicyclohexane dianhydride, p-phenylenebis(trimellitate anhydride), ethylenetetracarboxylic dianhydride, 1,2 ,3,4-butanetetracarboxylic dianhydride, decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7- Hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic acid dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, bis(exo-bicyclo[2,2,1]heptane-2,3-dicarboxylic dianhydride, bicyclo-[2,2 ,2]-oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 2,2- bis[4-(3,4-dicarboxyphenyl)phenyl]hexafluoropropane dianhydride, 4,4′-bis(3,4-dicarboxyphenoxy)diphenylsulfide dianhydride, 1,4-bis(2 -hydroxyhexafluoroisopropyl)benzenebis(trimellitic anhydride), 1,3-bis(2-hydroxyhexafluoroisopropyl)benzenebis(trimellitic anhydride), 5-(2,5-dioxotetrahydrofuryl )-3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, tetrahydrofuran-2,3,4,5-tetracarboxylic dianhydride, etc. can be used, and these can be used alone or in combination of two or more.

（式中、Ｒ１及びＲ２は炭素原子数１～３０の二価の炭化水素基を示し、それぞれ同一でも異なっていてもよく、Ｒ３及びＲ４は一価の炭化水素基を示し、それぞれ同一でも異なっていてもよく、ｍは１以上の整数である） In addition, the diamine used as a raw material for the polyimide is not particularly limited. , 4′-diaminodiphenyl ether, 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether methane, bis(4-amino-3,5-dimethylphenyl)methane, bis(4 -amino-3,5-diisopropylphenyl)methane, 3,3'-diaminodiphenyldifluoromethane, 3,4'-diaminodiphenyldifluoromethane, 4,4'-diaminodiphenyldifluoromethane, 3,3'-diaminodiphenylsulfone , 3,4′-diaminodiphenyl sulfone, 4,4′-diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfide, 3,4′-diaminodiphenyl sulfide, 4,4′-diaminodiphenyl sulfide, 3,3′ -diaminodiphenyl ketone, 3,4'-diaminodiphenyl ketone, 4,4'-diaminodiphenyl ketone, 2,2-bis(3-aminophenyl)propane, 2,2'-(3,4'-diaminodiphenyl) Propane, 2,2-bis(4-aminophenyl)propane, 2,2-bis(3-aminophenyl)hexafluoropropane, 2,2-(3,4'-diaminodiphenyl)hexafluoropropane, 2,2 -bis(4-aminophenyl)hexafluoropropane, 1,3-bis(3-aminophenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene , 3,3′-(1,4-phenylenebis(1-methylethylidene))bisaniline, 3,4′-(1,4-phenylenebis(1-methylethylidene))bisaniline, 4,4′-(1 ,4-phenylenebis(1-methylethylidene))bisaniline, 2,2-bis(4-(3-aminophenoxy)phenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 2,2-bis(4-(3-aminophenoxy)phenyl)hexafluoropropane, 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane, bis(4-(3-aminophenoxy) phenyl) sulfide, bis(4-(4 -aminophenoxy)phenyl)sulfide, bis(4-(3-aminophenoxy)phenyl)sulfone, bis(4-(4-aminophenoxy)phenyl)sulfone, aromatic diamines such as 3,5-diaminobenzoic acid, 1 ,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1, 9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,2-diaminocyclohexane, diaminopolysiloxane represented by the following general formula (1), 1,3- Bis(aminomethyl)cyclohexane, polyoxyalkylenes such as Jeffamine D-230, D-400, D-2000, D-4000, ED-600, ED-900, ED-2001, EDR-148 manufactured by Sun Techno Chemical Co., Ltd. Aliphatic diamines such as diamines can be used, and one or more of these can be used in combination. The polyimide resin preferably has a glass transition temperature of 0 to 200° C. and a weight average molecular weight of 10,000 to 200,000.

(Wherein, R1 and R2 represent a divalent hydrocarbon group having 1 to 30 carbon atoms and may be the same or different, and R3 and R4 represent a monovalent hydrocarbon group and may be the same or different. and m is an integer greater than or equal to 1)

In addition to the above, the phenoxy resin, which is one of the preferred thermoplastic resins, is preferably a resin obtained by a method of reacting various bisphenols with epichlorohydrin or a method of reacting a liquid epoxy resin with bisphenols. , bisphenol A, bisphenol bisphenol AF, bisphenol AD, bisphenol F, bisphenol S. Phenoxy resins are similar in structure to epoxy resins, and therefore have good compatibility with epoxy resins, and are suitable for imparting good adhesiveness to adhesive films.

Examples of the phenoxy resin used in the present invention include resins having repeating units represented by the following general formula (2).

In general formula (2) above, X represents a single bond or a divalent linking group. The divalent linking group includes an alkylene group, a phenylene group, --O--, --S--, --SO-- or --SO ₂ --. Here, the alkylene group is preferably an alkylene group having 1 to 10 carbon atoms, more preferably -C(R1)(R2)-. R1 and R2 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 and 2-ethylhexyl. , 1,3,3-trimethylbutyl and the like. Also, the alkyl group may be substituted with a halogen atom, such as a trifluoromethyl group. X is preferably an alkylene group, -O-, -S-, a fluorene group or -SO ₂ -, more preferably an alkylene group or -SO ₂ -. Among them, -C(CH ₃ ) ₂ -, -CH(CH ₃ )-, -CH ₂ - and -SO ₂ - are preferred, and -C(CH ₃ ) ₂ -, -CH(CH ₃ )- and - CH ₂ — is more preferred, and —C(CH ₃ ) ₂ — is particularly preferred.

If the phenoxy resin represented by the general formula (2) has a repeating unit, even if the resin has a plurality of repeating units in which X in the general formula (2) is different, X is the same repeating unit It may be composed only of In the present invention, a resin in which X is composed only of the same repeating unit is preferred.

In addition, when the phenoxy resin represented by the general formula (2) contains a polar substituent such as a hydroxyl group or a carboxyl group, compatibility with the thermally polymerizable component is improved, and uniform appearance and properties are imparted. be able to.

When the mass average molecular weight of the phenoxy resin is 5,000 or more, it is excellent in terms of film formability. It is more preferably 10,000 or more, and still more preferably 30,000 or more. Further, when the weight average molecular weight is 150,000 or less, it is preferable from the viewpoint of fluidity during thermocompression bonding and compatibility with other resins. More preferably, it is 100,000 or less. Also, 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 still more preferably 50° C. or higher. When the glass transition temperature is 150° C., the adhesive strength of the adhesive layer 13 during die bonding is excellent, and it is more preferably 120° C. or lower, still more preferably 110° C. or lower.

On the other hand, the functional group in the polymer containing the functional group includes, for example, glycidyl group, acryloyl group, methacryloyl group, hydroxyl group, carboxyl group, isocyanurate group, amino group, amide group, etc. Among them, glycidyl group is preferable. .

Examples of the functional group-containing high molecular weight component include (meth)acrylic copolymers containing functional groups such as glycidyl groups, hydroxyl groups, and carboxyl groups.

As the (meth)acrylic copolymer, for example, a (meth)acrylic ester copolymer, acrylic rubber, or the like can be used, and acrylic rubber is preferable. Acrylic rubber is a rubber containing acrylic acid ester as a main component and mainly composed of a copolymer such as butyl acrylate and acrylonitrile, or a copolymer such as ethyl acrylate and acrylonitrile.

When a glycidyl group is contained as a functional group, the amount of the glycidyl group-containing repeating unit is preferably 0.5 to 6.0% by weight, more preferably 0.5 to 5.0% by weight, and 0.8 to 5% by weight. 0% by weight is particularly preferred. A glycidyl group-containing repeating unit is a constituent monomer of a (meth)acrylic copolymer containing a glycidyl group, specifically glycidyl acrylate or glycidyl methacrylate. When the amount of the glycidyl group-containing repeating unit is within this range, it is possible to ensure adhesive strength and prevent gelation.

Constituent monomers of the (meth)acrylic copolymer other than glycidyl acrylate and glycidyl methacrylate include, for example, ethyl (meth)acrylate, butyl (meth)acrylate, etc. These may be used alone or in combination of two or more. You can also use In the present invention, ethyl (meth)acrylate refers to ethyl acrylate and/or ethyl methacrylate. When using a combination of functional monomers, the mixing ratio may be determined in consideration of the glass transition temperature of the (meth)acrylic copolymer. A glass transition temperature of −50° C. or higher is preferable in terms of excellent film formability and suppression of excessive tackiness at room temperature. If the tack force at room temperature is excessive, handling of the adhesive layer becomes difficult. It is more preferably -20°C or higher, and still more preferably 0°C or higher. Further, when the glass transition temperature is 30° C. or lower, the adhesive strength of the adhesive layer during die bonding is excellent, and it is more preferably 20° C. or lower.

When the above-mentioned monomers are polymerized to produce a high molecular weight component containing a functional monomer, the polymerization method is not particularly limited. For example, methods such as pearl polymerization and solution polymerization can be used. is preferred.

In the present invention, when the weight-average molecular weight of the high-molecular-weight component containing the functional monomer is 100,000 or more, it is excellent in film formability, more preferably 200,000 or more, further preferably 500,000 or more. . Further, when the weight average molecular weight is adjusted to 2,000,000 or less, it is excellent in terms of improving the heat fluidity of the adhesive layer during die bonding. If the heat fluidity of the adhesive layer during die bonding is improved, the adhesion between the adhesive layer and the adherend can be improved and the adhesive force can be improved. Become. It is more preferably 1,000,000 or less, still more preferably 800,000 or less, and if it is 500,000 or less, even greater effects can be obtained.

Further, the thermally polymerizable component is not particularly limited as long as it is polymerized by heat. Group-bearing compounds and trigger materials can be used alone or in combination of two or more types. It is preferable to contain an effective thermosetting resin together with a curing agent and an accelerator. Examples of thermosetting resins include epoxy resins, acrylic resins, silicone resins, phenol resins, thermosetting polyimide resins, polyurethane resins, melamine resins, urea resins, and the like. It is most preferable to use an epoxy resin in terms of obtaining an adhesive layer having excellent adhesion.

The above epoxy resin is not particularly limited as long as it cures and has an adhesive action. Bifunctional epoxy resins such as bisphenol A type epoxy, novolac type epoxy resins such as phenol novolac type epoxy resins and cresol novolak type epoxy resins. etc. can be used. In addition, commonly known resins such as polyfunctional epoxy resins, glycidylamine type epoxy resins, heterocycle-containing epoxy resins, and alicyclic epoxy resins can be applied.

Examples of the above-mentioned bisphenol A type epoxy resins include the Mitsubishi Chemical Epicote series (Epikote 807, Epicote 815, Epicote 825, Epicote 827, Epicote 828, Epicote 834, Epicote 1001, Epicote 1004, Epicote 1007, Epicote 1009), Dow DER-330, DER-301, DER-361 manufactured by Chemical Co., and YD8125, YDF8170 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., and the like. Examples of the phenolic novolac type epoxy resins include Epicoat 152 and Epicote 154 manufactured by Mitsubishi Chemical Corporation, EPPN-201 manufactured by Nippon Kayaku Co., Ltd., DEN-438 manufactured by Dow Chemical Co., etc., and o-cresol. As the novolac type epoxy resin, EOCN-102S, EOCN-103S, EOCN-104S, EOCN-1012, EOCN-1025, EOCN-1027 manufactured by Nippon Kayaku Co., Ltd., YDCN701, YDCN702 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., YDCN703, YDCN704 etc. are mentioned. Examples of the polyfunctional epoxy resins include Epon 1031S manufactured by Mitsubishi Chemical Corporation, Araldite 0163 manufactured by Ciba Specialty Chemicals, and Denacol EX-611, EX-614, EX-614B, and EX-622 manufactured by Nagase ChemteX Corporation. , EX-512, EX-521, EX-421, EX-411, EX-321 and the like. Examples of the above amine-type epoxy resins include Epicoat 604 manufactured by Mitsubishi Chemical Co., Ltd., YH-434 manufactured by Tohto Kasei Co., Ltd., TETRAD-X and TETRAD-C manufactured by Mitsubishi Gas Chemical Co., Ltd., and Sumitomo Chemical Co., Ltd. and ELM-120. Examples of the heterocycle-containing epoxy resin include Araldite PT810 manufactured by Ciba Specialty Chemicals, ERL4234, ERL4299, ERL4221, and ERL4206 manufactured by UCC. These epoxy resins can be used alone or in combination of two or more.

In order to cure the thermosetting resin, additives may be added as appropriate. Examples of such additives include curing agents, curing accelerators, catalysts, and the like. When catalysts are added, co-catalysts can be used as necessary.

When an epoxy resin is used as the thermosetting resin, it is preferable to use an epoxy resin curing agent or a curing accelerator, and it is more preferable to use them together. Examples of curing agents include phenolic resins, dicyandiamide, boron trifluoride complex compounds, organic hydrazide compounds, amines, polyamide resins, imidazole compounds, urea or thiourea compounds, polymercaptan compounds, and polysulfide resins having mercapto groups at their ends. , acid anhydrides, and light/ultraviolet curing agents. These can be used alone or in combination of two or more. Among these, boron trifluoride complex compounds include boron trifluoride-amine complexes with various amine compounds (preferably primary amine compounds), and organic hydrazide compounds include isophthalic acid dihydrazide.

Examples of phenolic resins include phenol novolak resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolac resins, novolac type phenol resins such as nonylphenol novolak resins, resol type phenol resins, and polyoxystyrenes such as polyparaoxystyrene. mentioned. Among them, phenolic compounds having at least two phenolic hydroxyl groups in the molecule are preferred.

Examples of the phenolic compound having at least two phenolic hydroxyl groups in the molecule include phenol novolak resin, cresol novolak resin, t-butylphenol novolak resin, dicyclopentadiene cresol novolak resin, dicyclopentadiene phenol novolak resin, Xylylene-modified phenol novolak resin, naphthol novolak resin, trisphenol novolak resin, tetrakisphenol novolak resin, bisphenol A novolak resin, poly-p-vinylphenol resin, phenol aralkyl resin and the like. Among these phenolic resins, phenolic novolac resins and phenolic aralkyl resins are particularly preferable, and can improve connection reliability.

Examples of amines include chain aliphatic amines (diethylenetriamine, triethylenetetramine, hexamethylenediamine, N,N-dimethylpropylamine, benzyldimethylamine, 2-(dimethylamino)phenol, 2,4,6-tris(dimethyl aminomethyl)phenol, m-xylenediamine, etc.), cycloaliphatic amines (N-aminoethylpiperazine, bis(3-methyl-4-aminocyclohexyl)methane, bis(4-aminocyclohexyl)methane, menzenediamine, iso forondiamine, 1,3-bis(aminomethyl)cyclohexane, etc.), heterocyclic amines (piperazine, N,N-dimethylpiperazine, triethylenediamine, melamine, guanamine, etc.), aromatic amines (metaphenylenediamine, 4,4' -diaminodiphenylmethane, diamino, 4,4'-diaminodiphenylsulfone, etc.), polyamide resin (preferably polyamidoamine, condensate of dimer acid and polyamine), imidazole compound (2-phenyl-4,5-dihydroxymethylimidazole, 2 -methylimidazole, 2,4-dimethylimidazole, 2-n-heptadecylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, epoxy-imidazole adducts, etc.), urea or thiourea compounds (N,N- dialkylurea compounds, N,N-dialkylthiourea compounds, etc.), polymercaptan compounds, polysulfide resins having mercapto groups at their ends, acid anhydrides (tetrahydrophthalic anhydride, etc.), light/ultraviolet curing agents (diphenyl iodine, umhexa fluorophosphate, triphenylsulfonium hexafluorophosphate, etc.).

The curing accelerator is not particularly limited as long as it cures the thermosetting resin. 4-methylimidazole-tetraphenylborate, 1,8-diazabicyclo[5.4.0]undecene-7-tetraphenylborate and the like.
Examples of imidazoles include imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1 -benzyl-2-ethylimidazole, 1-benzyl-2-ethyl-5-methylimidazole, 2-phenyl-4-methyl-5-hydroxydimethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole and the like. .

The content of the epoxy resin curing agent or curing accelerator in the adhesive layer is not particularly limited, and the optimum content varies depending on the type of curing agent or curing accelerator.

The blending ratio of the epoxy resin and the phenol resin is preferably, for example, such that the hydroxyl groups in the phenol resin are in an amount of 0.5 to 2.0 equivalents per equivalent of the epoxy groups in the epoxy resin component. More preferably, it is 0.8 to 1.2 equivalents. That is, if the mixing ratio of the two is out of the above range, the curing reaction does not proceed sufficiently, and the properties of the adhesive layer tend to deteriorate. In one embodiment, the other thermosetting resin and the curing agent are 0.5 to 20 parts by mass of the curing agent with respect to 100 parts by mass of the thermosetting resin, and in another embodiment, the curing agent is 1 to 10 parts by mass. The content of the curing accelerator is preferably less than the content of the curing agent. 95 parts by mass is more preferable. By adjusting the amount within the above range, it is possible to assist the sufficient progress of the curing reaction. The content of the catalyst is preferably 0.001 to 1.5 parts by mass, more preferably 0.01 to 1.0 parts by mass, with respect to 100 parts by mass of the thermosetting resin.

In addition, the adhesive layer 13 of the present invention can appropriately contain a filler according to its use. As a result, the dicing property of the adhesive layer in the uncured state is improved, the handleability is improved, the melt viscosity is adjusted, the thixotropic property is imparted, and the cured adhesive layer is imparted with thermal conductivity and adhesive strength. It is possible to improve
An inorganic filler is preferable as the filler used in the present invention. The inorganic filler is not particularly limited, and examples thereof include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, aluminum nitride, aluminum borate whiskers, and boron nitride. , crystalline silica, amorphous silica, antimony oxide and the like can be used. Moreover, these can also be used individually or in mixture of 2 or more types.

Among the above inorganic fillers, alumina, aluminum nitride, boron nitride, crystalline silica, amorphous silica, and the like are preferably used from the viewpoint of improving thermal conductivity. In terms of adjusting the melt viscosity and imparting thixotropic properties, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, alumina, and crystalline silica. , amorphous silica and the like are preferably used. From the viewpoint of improving dicing properties, it is preferable to use alumina or silica.

When the filler content is 30% by mass or more, the wire bondability is excellent. At the time of wire bonding, it is preferable that the post-hardening storage modulus of the adhesive layer bonding the chip to which the wire is attached is adjusted to a range of 20 to 1000 MPa at 170° C., and the filler content is 30% by mass or more. It is easy to adjust the storage elastic modulus of the adhesive layer after curing to this range. Further, when the content of the filler is 75% by mass or less, the film formability and heat fluidity of the adhesive layer during die bonding are excellent. If the heat fluidity of the adhesive layer during die bonding is improved, the adhesion between the adhesive layer and the adherend can be improved and the adhesive force can be improved. Become. It is more preferably 70% by mass or less, and still more preferably 60% by mass or less.

The adhesive layer of the present invention can contain two or more fillers having different average particle diameters as the filler. In this case, compared with the case where a single filler is used, in the raw material mixture before film formation, it becomes easier to prevent the viscosity increase when the filler content is high or the viscosity decrease when the filler content is low, Good film formability can be easily obtained, the fluidity of the uncured adhesive layer can be optimally controlled, and excellent adhesive strength can be easily obtained after curing of the adhesive layer.

In the adhesive layer of the present invention, the filler preferably has an average particle size of 2.0 μm or less, more preferably 1.0 μm or less. When the average particle size of the filler is 2.0 µm or less, it becomes easy to make the film thinner. Thin film here implies a thickness of 20 μm or less. Moreover, when it is 0.01 μm or more, the dispersibility is good.
Furthermore, from the viewpoint of preventing the viscosity increase or decrease of the raw material mixture before film formation, optimally controlling the fluidity of the uncured adhesive layer, and improving the adhesive strength of the adhesive layer after curing, the average particle size is in the range of 0.1 to 1.0 μm, and the second filler has an average primary particle size in the range of 0.005 to 0.03 μm. A first filler having an average particle diameter in the range of 0.1 to 1.0 μm and 99% or more of the particles are distributed in the particle diameter range of 0.1 to 1.0 μm, and an average primary particle diameter It is preferred to include a second filler having a particle size within the range of 0.005-0.03 μm and having 99% or more of the particles distributed within the particle size range of 0.005-0.1 μm.
Average particle size in the context of the present invention means the D50 value of the cumulative volume distribution curve at which 50% by volume of the particles have a diameter smaller than this value. In the present invention, the average particle size or D50 value is measured by a laser diffraction method, for example using a Malvern Mastersizer 2000 manufactured by Malvern Instruments. In this technique, the size of particles in a dispersion is measured using diffraction of a laser beam, based on an application of either Fraunhofer or Mie theory. In the present invention, the Mie theory or modified Mie theory for non-spherical particles is used and the mean particle size or D50 value relates to scatterometry from 0.02 to 135° to the incident laser beam.

In one aspect of the present invention, a thermoplastic resin having a weight average molecular weight of 5000 to 200,000 and 10 to 40% by mass of the adhesive composition constituting the adhesive layer 13 are 10 to 40% by mass. and 30 to 75% by weight of filler. In this embodiment, the filler content may be 30-60% by weight, or 40-60% by weight. Further, the mass average molecular weight of the thermoplastic resin may be 5,000 to 150,000, or 10,000 to 100,000.
In another aspect, 10 to 20% by mass of a thermoplastic resin having a weight average molecular weight of 200,000 to 2,000,000 and 20 to 50% by mass of the adhesive composition constituting the adhesive layer 13 and 30 to 75% by weight of filler. In this embodiment, the filler content may be 30-60% by weight, or 30-50% by weight. Also, the mass average molecular weight of the thermoplastic resin may be 200,000 to 1,000,000, or 200,000 to 800,000.
By adjusting the compounding ratio, it is possible to optimize the storage elastic modulus and fluidity of the adhesive layer 13 after curing, and there is a tendency to obtain sufficient heat resistance at high temperatures.

In the semiconductor processing tape 10 of the present invention, the adhesive layer 13 may be formed by directly or indirectly laminating a preformed film (hereinafter referred to as an adhesive film) on the base film 11. . It is preferable that the temperature during lamination is in the range of 10 to 100° C. and a linear pressure of 0.01 to 10 N/m is applied. Such an adhesive film may have an adhesive layer 13 formed on a release film. In that case, the release film may be peeled off after lamination, or the tape 10 for semiconductor processing may be used as it is. It may be used as a cover film for the film and peeled off when the wafers are bonded.

The adhesive film may be laminated on the entire surface of the adhesive layer 12. Alternatively, an adhesive film cut (pre-cut) into a shape corresponding to the wafer to be bonded in advance may be laminated on the adhesive layer 12. good. When the adhesive films corresponding to the wafers are laminated in this way, as shown in FIG. There is no adhesive layer 13 and only the adhesive layer 12 is present. In general, since the adhesive layer 13 is difficult to peel off from the adherend, using a pre-cut adhesive film allows the ring frame 20 to be bonded to the adhesive layer 12, so that the ring frame 20 can be attached to the adhesive layer 12 when the tape is peeled off after use. It is possible to obtain the effect that adhesive residue on the frame 20 is less likely to occur.

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

Semiconductor device manufacturing method (A)
(a) a step of bonding a surface protection tape to the surface of the wafer on which the circuit pattern is formed;
(b) a back grinding step of grinding the back surface of the wafer;
(c) bonding an adhesive film bonded to the adhesive layer of the semiconductor processing tape to the back surface of the wafer while the wafer is heated at 70 to 80° C.;
(d) peeling off the surface protection tape from the wafer surface;
(e) irradiating a portion of the wafer to be divided into a laser beam to form a modified region inside the wafer by multiphoton absorption;
(f) dividing the wafer and the adhesive film along dividing lines by expanding the semiconductor processing tape to obtain a plurality of chips with adhesive films;
(g) a step of heat shrinking a portion of the tape for semiconductor processing which does not overlap with the chip to remove the slack generated in the expanding step to maintain the gap between the chips;
(h) picking up the chip with the adhesive layer from the adhesive layer of a semiconductor processing tape;
A method of manufacturing a semiconductor device comprising:
This semiconductor device manufacturing method is a method using stealth dicing.

Semiconductor device manufacturing method (B)
(a) a step of bonding a surface protection tape to the surface of the wafer on which the circuit pattern is formed;
(b) a back grinding step of grinding the back surface of the wafer;
(c) while the wafer is heated at 70 to 80° C., bonding the adhesive film bonded to the adhesive layer of the semiconductor processing tape to the back surface of the wafer;
(d) peeling off the surface protection tape from the wafer surface;
(e) irradiating a laser beam from the surface of the wafer along a dividing line to divide it into individual chips;
(f) expanding the semiconductor processing tape to cut the adhesive film corresponding to the chips to obtain a plurality of chips with adhesive films;
(g) a step of heat shrinking a portion of the tape for semiconductor processing which does not overlap with the chip to remove the slack generated in the expanding step to maintain the gap between the chips;
(h) picking up the chip with the adhesive layer from the adhesive layer of a semiconductor processing tape;
A method of manufacturing a semiconductor device comprising:
The manufacturing method of this semiconductor device is a method using full-cut laser dicing.

Semiconductor device manufacturing method (C)
(a) a step of bonding a surface protection tape to the surface of the wafer on which the circuit pattern is formed;
(b) a back grinding step of grinding the back surface of the wafer;
(c) while the wafer is heated at 70 to 80° C., bonding the adhesive film bonded to the adhesive layer of the semiconductor processing tape to the back surface of the wafer;
(d) peeling off the surface protection tape from the wafer surface;
(e) using a dicing blade to cut the wafer along dicing lines to divide it into individual chips;
(f) expanding the semiconductor processing tape to cut the adhesive film corresponding to the chips to obtain a plurality of chips with adhesive films;
(g) a step of heat shrinking a portion of the tape for semiconductor processing which does not overlap with the chip to remove the slack generated in the expanding step to maintain the gap between the chips;
(h) picking up the chip with the adhesive layer from the adhesive layer of a semiconductor processing tape;
A method of manufacturing a semiconductor device comprising:
The manufacturing method of this semiconductor device is a method using full-cut blade dicing.

Semiconductor device manufacturing method (D)
(a) using a dicing blade to cut a wafer on which a circuit pattern is formed to a depth less than the thickness of the wafer along the planned dividing line;
(b) laminating a surface protection tape on the wafer surface;
(c) a back grinding step of grinding the back surface of the wafer;
(d) bonding the adhesive film bonded to the adhesive layer of the semiconductor processing tape to the back surface of the chip while the wafer is heated at 70 to 80° C.;
(e) peeling off the surface protection tape from the wafer surface;
(f) expanding the semiconductor processing tape to cut the adhesive film corresponding to the chips to obtain a plurality of chips with adhesive films;
(g) a step of heat shrinking a portion of the tape for semiconductor processing which does not overlap with the chip to remove the slack generated in the expanding step to maintain the gap between the chips;
(h) picking up the chip with the adhesive layer from the adhesive layer of a semiconductor processing tape;
A method of manufacturing a semiconductor device comprising:
The manufacturing method of this semiconductor device is a method using half-cut blade dicing.

Semiconductor device manufacturing method (E)
(a) a step of bonding a surface protection tape to the surface of the wafer on which the circuit pattern is formed;
(b) a step of irradiating a portion of the wafer scheduled to be divided with a laser beam to form a modified region inside the wafer by multiphoton absorption;
(c) a back grinding step of grinding the back surface of the wafer;
(d) bonding the adhesive layer of the semiconductor processing tape to the back surface of the wafer while the wafer is heated to 70 to 80° C.;
(e) peeling the surface protection tape from the wafer surface;
(f) dividing the wafer and the adhesive layer along dividing lines by expanding the semiconductor processing tape to obtain a plurality of chips with an adhesive film;
(g) a step of heat shrinking a portion of the tape for semiconductor processing which does not overlap with the chip to remove the slack generated in the expanding step and maintain the gap between the chips;
(h) picking up the chip with the adhesive layer from the adhesive layer of the semiconductor processing tape;
A method of manufacturing a semiconductor device comprising:
This semiconductor device manufacturing method is a method using stealth dicing.

<How to use>
A method of using the semiconductor processing tape 10 of the present invention when it is applied to the semiconductor device manufacturing method (A) will be described with reference to FIGS. 2 to 5. FIG. First, as shown in FIG. 2, a surface protection tape 14 for protecting the circuit pattern, which contains an ultraviolet curable component in the adhesive, is attached to the surface of the wafer W on which the circuit pattern is formed, and the back surface of the wafer W is adhered. A back grinding process for grinding is performed.

After the back grinding step, as shown in FIG. 3, the wafer W is placed on the heater table 25 of the wafer mounter with the surface side down, and then the semiconductor processing tape 10 is bonded to the back surface of the wafer W. do. The semiconductor processing tape 10 used here is a laminate of adhesive films precut into a shape corresponding to the wafer W to be bonded. The adhesive layer 12 is exposed around the area where 13 is exposed. The portion where the adhesive layer 13 of the semiconductor processing tape 10 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 at 70 to 80° C., and heat lamination is performed. In this embodiment, the adhesive tape 15 composed of the substrate film 11 and the adhesive layer 12 provided on the substrate film 11 and the adhesive layer 13 provided on the adhesive layer 12 are used. Although the semiconductor processing tape 10 having the adhesive tape is used, it is also possible to use an adhesive tape and a film-like adhesive, respectively. In this case, first, a film adhesive is adhered to the back surface of the wafer to form an adhesive layer, and the adhesive layer of the adhesive tape is adhered to this adhesive layer. At this time, the adhesive tape 15 according to the present invention is used as the adhesive tape.

Next, the wafer W to which the semiconductor processing tape 10 is adhered is unloaded from the heater table 25 and placed on the suction table 26 with the semiconductor processing tape 10 side down as shown in FIG. Then, from above the wafer W adsorbed and fixed to the adsorption table 26, the energy beam light source 27 is used to irradiate the substrate surface side of the surface protection tape 14 with ultraviolet rays of, for example, 1000 mJ/cm ² . The adhesive force to the wafer W is lowered, and the surface protection tape 14 is peeled off from the wafer W surface.

Next, as shown in FIG. 5, a portion of the wafer W to be divided is irradiated with a laser beam to form a modified region 32 inside the wafer W by multiphoton absorption.

Next, as shown in FIG. 6A, the semiconductor processing tape 10 to which the wafer W and the ring frame 20 are attached is placed on the stage 21 of the expanding device with the base film 11 side facing down. .

Next, as shown in FIG. 6(b), with the ring frame 20 fixed, the hollow columnar push-up member 22 of the expanding device is lifted to expand the semiconductor processing tape 10. As shown in FIG. As expansion conditions, the expansion speed is, for example, 5 to 500 mm/sec, and the expansion amount (push-up amount) is, for example, 5 to 25 mm. By stretching the semiconductor processing tape 10 in the radial direction of the wafer W in this manner, the wafer W is divided into chips 34 starting from the modified regions 32 . At this time, the adhesive layer 13 is prevented from being broken due to the expansion (deformation) at the portion adhered to the back surface of the wafer W, but the tension due to the expansion of the tape is concentrated at the positions between the chips 34 . and break. Therefore, as shown in FIG. 6C, the adhesive layer 13 is also cut together with the wafer W. Then, as shown in FIG. Thus, a plurality of chips 34 with adhesive layer 13 attached can be obtained.

Next, as shown in FIG. 7, the push-up member 22 is returned to its original position, and the slack of the semiconductor processing tape 10 generated in the previous expanding process is removed, thereby stably maintaining the interval between the chips 34. carry out the process. In this step, for example, hot air of 40 to 120° C. is applied to the annular heat-shrinking region 28 between the chip 34 region of the semiconductor processing tape 10 and the ring frame 20 using a hot air nozzle 29. The substrate film 11 is heat-shrunk by applying the heat, and the semiconductor processing tape 10 is made taut. Thereafter, the adhesive layer 12 is subjected to energy ray curing treatment, heat curing treatment, or the like to weaken the adhesive strength of the adhesive layer 12 to the adhesive layer 13, and then the chip 34 is picked up.

Although the semiconductor processing tape 10 according to the present embodiment has the adhesive layer 13 on the adhesive layer 12, the adhesive layer 13 may be omitted. In this case, the wafer may be laminated on the adhesive layer 12 and used to divide only the wafer, or when using a semiconductor processing tape, an adhesive layer prepared in the same manner as the adhesive layer 13 may be used. The film may be laminated on the adhesive layer 12 together with the wafer, and the wafer and the adhesive film may be separated.
<Example>
EXAMPLES Next, examples and comparative examples will be described in detail in order to further clarify the effects of the present invention, but the present invention is not limited to these examples.

[Production of semiconductor processing tape]
(1) Preparation of base film <Base film A>
Zinc ionomer of ethylene-methacrylic acid-ethyl methacrylate copolymer synthesized by radical polymerization method (methacrylic acid content 15%, ethyl methacrylate content 5%, softening point 72°C, melting point 90°C, density 0.96 g/cm ³ , zinc ion content of 5% by mass) was melted at 230° C. and formed into a long film having a thickness of 150 μm using an extruder. After that, the base film A was produced by stretching the long film in the TD direction so as to have a thickness of 90 μm.

<Base film B>
Base film B was produced in the same manner as base film A except that the long film had a thickness of 180 μm and was stretched in the TD direction so as to have a thickness of 90 μm.

<Base film C>
Base film C was produced in the same manner as base film A except that the long film had a thickness of 215 μm and was stretched in the TD direction so as to have a thickness of 90 μm.

<Base film D>
Zinc ionomer of ethylene-methacrylic acid-isobutyl methacrylate copolymer synthesized by radical polymerization method (methacrylic acid content 11%, isobutyl methacrylate content 9%, softening point 64°C, melting point 83°C, density 0.95 g/cm ³ and zinc ion content of 4% by mass) were melted at 230° C. and formed into a long film having a thickness of 150 μm using an extruder. After that, the base film D was produced by stretching the long film in the TD direction so as to have a thickness of 90 μm.

<Base film E>
Resin beads obtained by mixing a hydrogenated styrenic thermoplastic elastomer and homopropylene (PP) at a compounding ratio of 52:48 were melted at 200° C. and molded into a long film having a thickness of 150 μm using an extruder. After that, the base film E was produced by stretching the long film in the TD direction so as to have a thickness of 90 μm.

<Base film F>
Resin beads obtained by mixing a hydrogenated styrenic thermoplastic elastomer and homopropylene (PP) at a compounding ratio of 64:36 were melted at 200° C. and formed into a long film having a thickness of 150 μm using an extruder. Thereafter, the base film F was produced by stretching the long film in the TD direction so as to have a thickness of 90 μm.

<Base film G>
A base film G was produced in the same manner as the base film A, except that the long film had a thickness of 150 μm and was stretched in the MD direction so as to have a thickness of 90 μm.

<Base film H>
A base film H was produced in the same manner as the base film D except that the long film had a thickness of 150 μm and was stretched in the MD direction so as to have a thickness of 90 μm.

<Base film I>
A base film I was produced in the same manner as the base film A, except that the long film had a thickness of 90 μm and was not stretched.

<Base film J>
A base film J was produced in the same manner as the base film D, except that the long film had a thickness of 90 μm and was not stretched.

<Base film K>
Base film K was produced in the same manner as base film E, except that the long film had a thickness of 90 μm and was not subjected to stretching treatment.

<Base film L>
A base film K was produced in the same manner as the base film F, except that the long film had a thickness of 90 μm and was not stretched.

<Base film M>
A base film M was produced in the same manner as the base film A except that the long film had a thickness of 110 μm and was stretched in the TD direction so as to have a thickness of 90 μm.

<Base film N>
Base film N was produced in the same manner as base film A except that the long film had a thickness of 120 μm and was stretched in the TD direction so as to have a thickness of 90 μm.

(2) Preparation of acrylic copolymer The acrylic copolymer (A1) having a functional group is composed of 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate and methacrylic acid, and the ratio of 2-ethylhexyl acrylate is 60 mol%. , and a copolymer having a mass average molecular weight of 700,000 was prepared. Next, 2-isocyanatoethyl methacrylate was added so that the iodine value was 25 to prepare an acrylic copolymer having a glass transition temperature of −50° C., a hydroxyl value of 10 mgKOH/g, and an acid value of 5 mgKOH/g. .

(3) Preparation of adhesive composition Epoxy resin "1002" (manufactured by Mitsubishi Chemical Corporation, solid bisphenol A type epoxy resin, epoxy equivalent 600) 40 parts by mass, epoxy resin "806" (trade name manufactured by Mitsubishi Chemical Corporation, Bisphenol F type epoxy resin, epoxy equivalent 160, specific gravity 1.20) 100 parts by mass, curing agent "Dyhard 100SF" (manufactured by Degussa, trade name, dicyandiamide) 5 parts by mass, silica filler "SO-C2" (manufactured by ADMAFINE Co., Ltd. A composition consisting of 200 parts by mass of silica filler "Aerosil R972" (trade name of Nippon Aerosil Co., Ltd., average particle size of primary particle size 0.016 µm), and 3 parts by mass of silica filler. MEK was added to and mixed with stirring to obtain a uniform composition.
To this, 100 parts by mass of phenoxy resin "PKHH" (manufactured by INCHEM, mass average molecular weight 52,000, glass transition temperature 92 ° C.), "KBM-802" as a coupling agent (manufactured by Shin-Etsu Silicone Co., Ltd., trade name, Mercapto 0.6 parts by mass of propyltrimethoxysilane), and “Curesol 2PHZ-PW” as a curing accelerator (manufactured by Shikoku Kasei Co., Ltd., trade name, 2-phenyl-4,5-dihydroxymethylimidazole, decomposition temperature 230 ° C.) 0.5 parts by mass was added and stirred and mixed until uniform. Further, this was filtered through a 100-mesh filter and vacuum defoamed to obtain a varnish of the adhesive composition.

<Example 1>
A mixture obtained by adding 5 parts by mass of Coronate L (manufactured by Nippon Polyurethane) as a polyisocyanate to 100 parts by mass of the acrylic copolymer described above and adding 3 parts by mass of Esacure KIP 150 (manufactured by Lamberti) as a photopolymerization initiator. was dissolved in ethyl acetate and stirred to prepare an adhesive composition.
Next, this pressure-sensitive adhesive composition was applied to a release liner made of a release-treated polyethylene-terephthalate film so that the thickness after drying was 10 μm, and dried at 110° C. for 3 minutes. A pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer formed on a base film was produced by bonding with a film.

Next, the adhesive composition described above is applied to a release liner made of a release-treated polyethylene-terephthalate film so that the thickness after drying becomes 20 μm, dried at 110° C. for 5 minutes, and then released. An adhesive film having an adhesive layer formed on a liner was produced.

The adhesive sheet was cut into the shape shown in FIG. Also, the adhesive film was cut into the shape shown in FIG. 3 etc. so as to cover the back surface of the wafer. Then, the adhesive layer side of the adhesive sheet and the adhesive layer side of the adhesive film are adhered so that a portion where the adhesive layer 12 is exposed is formed around the adhesive film as shown in FIG. Together, a tape for semiconductor processing was produced.

<Examples 2 to 8, Comparative Examples 1 to 6>
Semiconductor processing tapes according to Examples 2 to 8 and Comparative Examples 1 to 6 were produced in the same manner as in Example 1, except that the base film shown in Table 1 was used.

The adhesive tape of the tape for semiconductor processing according to Examples and Comparative Examples was cut so as to have a length of 24 mm (the direction in which the amount of deformation was measured) and a width of 5 mm (the direction perpendicular to the direction in which the amount of deformation was measured). cut to pieces. Using a thermomechanical property tester (manufactured by Rigaku Co., Ltd., trade name: TMA8310), the deformation due to temperature in the two directions of MD and TD is measured by the tensile load method under the following measurement conditions. did.
(Measurement condition)
Measurement temperature: -60 to 100°C
Heating rate: 5°C/min
Measurement load: 19.6mN
Atmospheric gas: Nitrogen atmosphere (100 ml/min)
Sampling: 0.5s
Distance between chucks: 20 mm

Then, the thermal deformation rate was calculated by the following formula (1), the differential value of the thermal deformation rate for each 1° C. between 40° C. and 80° C. in the MD direction and the TD direction was obtained, and the sum was calculated. The results are shown in Tables 1 and 2.
Thermal deformation rate TMA (%) = (sample length displacement/sample length before measurement) x 100 (1)

[Evaluation of chip recognition error]
By the method shown below, the semiconductor processing tapes of the above examples and the above comparative examples were cut into chips from the wafer, and chip recognition errors were evaluated.

(a) a step of bonding a surface protection tape to the surface of the wafer on which the circuit pattern is formed;
(b) a step of irradiating a portion of the wafer scheduled to be divided with a laser beam to form a modified region inside the wafer by multiphoton absorption;
(c) a back grinding step of grinding the back surface of the wafer;
(d) bonding the adhesive layer of the semiconductor processing tape to the back surface of the wafer while the wafer is heated to 70 to 80° C.;
(e) peeling the surface protection tape from the wafer surface;
(f) dividing the wafer and the adhesive layer along dividing lines by expanding the semiconductor processing tape to obtain a plurality of chips with an adhesive film; and (g) the semiconductor processing tape. (annular region between the region where the chip exists and the ring frame) that does not overlap with the chip is heated and contracted to remove the slack generated in the expanding step of (f), and the gap between the chips holding the
(h) picking up the chip attached with the adhesive layer from the adhesive layer of the semiconductor processing tape;

In the step (d), the wafer was attached to the semiconductor processing tape so that the cutting lines of the wafer were aligned with the MD direction and the TD direction of the base film.

In the step (f), the dicing ring frame bonded to the semiconductor processing tape by DDS2300 manufactured by Disco Co., Ltd. is pressed down by the expand ring of DDS2300 manufactured by Disco Co., Ltd., and the wafer bonding portion of the semiconductor processing tape is pressed down. The expansion was carried out by pressing the portion of the outer periphery, which does not overlap the wafer, against a circular push-up member. (f) As for the conditions of the step, the amount of expansion was adjusted so that the expansion speed was 300 mm/sec and the expansion height was 10 mm. Here, the amount of expansion refers to the amount of change in relative position between the ring frame and the push-up member before and after the push-down. The chip size was set to 1×1 mm square.

In step (g), the film was expanded again under the conditions of an expansion speed of 1 mm/sec and an expansion height of 10 mm at normal temperature, and then subjected to heat shrink treatment under the following conditions.
[Condition 1]
Heater setting temperature: 220°C
Hot air volume: 40L/min
Distance between heater and semiconductor processing tape: 20 mm
Heater rotation speed: 7°/sec
[Condition 2]
Heater setting temperature: 220°C
Hot air volume: 40L/min
Distance between heater and semiconductor processing tape: 20 mm
Heater rotation speed: 5°/sec

The semiconductor processing tapes of Examples 1 to 8 and Comparative Examples 1 to 6 were picked up after the step (g), and the chips could not be correctly recognized because the boundaries between adjacent chips could not be determined. , the frequency of occurrence was evaluated as a chip recognition error when the chip could not be picked up. A product with a chip recognition error frequency of 0% under both conditions 1 and 2 of the above process (g) is evaluated as a good product, and a product with a chip recognition error frequency of less than 1% under condition 2. Those with a chip recognition error frequency of 1% or more and less than 3% under condition 2 are regarded as acceptable products. A product with a frequency of occurrence of 3% or more was evaluated as a defective product with "x". The results are shown in Tables 1 and 2. In the evaluation, as shown in FIG. 8, around the chip 50a on the far right side in FIG. 100 chips were picked up and evaluated around the edge chip 50b, the chip 51 at the farthest end without chipping in the TD direction of the adhesive tape, and the chip 52 located in the center.

As shown in Table 1, the tapes for semiconductor processing according to Examples 1 to 8 were measured by a thermomechanical property tester in the MD direction of the adhesive tape when the temperature was raised between 40 ° C. and 80 ° C. for each 1 ° C. The sum of the average value of the differential value of the deformation rate and the average value of the differential value of the thermal deformation rate for each 1 °C between 40 ° C and 80 ° C measured by a thermomechanical property tester in the TD direction when the temperature is raised is negative. Since it is a value, it is easy to discriminate the boundary between adjacent chips, and the frequency of occurrence of chip recognition errors in image recognition during picking up is low, resulting in favorable results.

On the other hand, as shown in Table 2, the tapes for semiconductor processing according to Comparative Examples 1 to 6 were measured by a thermomechanical property tester in the MD direction of the adhesive tape at every 1 ° C. The sum of the average value of the differential value of the thermal deformation rate and the average value of the differential value of the thermal deformation rate for each 1 ° C between 40 ° C and 80 ° C measured when the temperature is raised by a thermomechanical property tester in the TD direction is not a negative value, the frequency of occurrence of chip recognition errors is high and the result is inferior.

10: Tape for semiconductor processing 11: Base film 12: Adhesive layer 13: Adhesive layer 22: Push-up member 28: Heat shrinkage region 29: Hot air nozzle

Claims (3)

An adhesive tape having a base film and an adhesive layer formed on at least one side of the base film,
The base film is made of a thermoplastic crosslinked resin other than an ionomer resin,
The pressure-sensitive adhesive tape is an average value of the differential values of the thermal deformation rate for each 1 ° C. between 40 ° C. and 80 ° C. measured when the temperature is raised under a tensile load of 19.6 mN with a thermomechanical property tester in the MD direction, The sum of the average value of the differential value of the thermal deformation rate for each 1 ° C. between 40 ° C. and 80 ° C. measured at the temperature rise under a tensile load of 19.6 mN with a thermomechanical property tester in the TD direction is a negative value. A tape for semiconductor processing, characterized by: 2. The tape for semiconductor processing according to claim 1, wherein an adhesive layer is laminated on the adhesive layer side. 3. The semiconductor processing tape according to claim 1, which is used for full-cut and half-cut blade dicing, laser dicing, or laser stealth dicing.

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