TWI771521B - Manufacturing method of semiconductor device - Google Patents

Abstract

The present invention relates to a method for manufacturing a semiconductor device, comprising a base material (Y1) and an adhesive layer (X1), in which any layer contains expandable particles, and a method for manufacturing a semiconductor device using an expandable adhesive sheet (A). ,in About the manufacturing method of the semiconductor device having the following steps (1) to (3). Process (1): After attaching the workpiece to the adhesive layer (X1) of the adhesive sheet (A), cutting the workpiece to obtain a plurality of wafers on the adhesive layer (X1) . Process (2): Using an adhesive sheet (B) having a base material (Y2) and an adhesive layer (X2), on the surface opposite to the surface to which the adhesive layers (X1) of the plurality of chips are bonded Engineering of the adhesive layer (X2) of the sheet (B). Process (3): A process of expanding the expandable particles and separating the plurality of wafers and the adhesive sheet (A) attached to the adhesive sheet (B).

Description

Manufacturing method of semiconductor device

The present invention relates to a method of manufacturing a semiconductor device.

In recent years, the miniaturization, weight reduction and high functionalization of electronic equipment have progressed, and along with these, the semiconductor devices mounted in electronic equipment are also required to be reduced in size, thickness and density. Semiconductor chips have packages that are mounted close to their size. Such a package is also called CSP (Chip Scale Package). Examples of CSP systems include: WLP (Wafer Level Package), which is processed to the final packaging process with a wafer size, and PLP (PLP), which is processed to a final packaging process with a panel size larger than the wafer size. Panel Level Package), etc.

WLP and PLP are classified into fan-in (Fan-In) type and fan-out (Fan-Out) type. In the case of fan-out WLP (hereinafter, also referred to as "FOWLP") and PLP (hereinafter, also referred to as "FOPLP"), the semiconductor wafer is formed into a larger area than the wafer size, and the sealing material is sealed. It is coated to form a semiconductor chip enclosure, and rewiring layers or external electrodes are formed not only on the circuit surface of the semiconductor chip but also on the surface area of the encapsulant. For example, in Patent Document 1, it is described that a plurality of semiconductor wafers are divided into individual pieces from a semiconductor wafer, and the circuit forming surface is left, and an expansion wafer is formed around the periphery using a mold member, and the area outside the semiconductor wafer is formed. , a manufacturing method of a semiconductor package formed by extending the redistribution pattern. In the manufacturing method described in Patent Document 1, a semiconductor wafer is subjected to a dicing process in which it is adhered to a wafer mounting tape for dicing (hereinafter, also referred to as a "dicing tape") and is separated into pieces. The plurality of semiconductor chips obtained in the dicing process are transferred to a wafer mounting tape for expansion (hereinafter, also referred to as "expansion tape", and the expansion tape is stretched so that the plurality of semiconductor chips are in contact with each other. The expansion project of distance expansion.

Dicing tape is used in the manufacturing process of semiconductor devices to separate workpieces represented by semiconductor wafers. It requires a certain adhesive force to prevent peeling and position shift of the workpiece during dicing. On the other hand, separability is required for easily separating individualized wafers after dicing. Patent Document 2 discloses a dicing tape having a base material and an adhesive layer as a dicing tape for improving the releasability after dicing, and a dicing tape having a material of which the adhesive force is cured by ultraviolet irradiation and the adhesive force is reduced as a material of the adhesive layer is used. [Prior Art Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2010/058646 [Patent Document 2] Japanese Patent Application Laid-Open No. 2016-167510

[The problem to be solved by the invention]

However, in the dicing tape described in Patent Document 2, a certain degree of adhesive force remains because the wafer and the adhesive layer are adhered to the entire adhesive surface after ultraviolet irradiation. Therefore, when the wafer obtained by dicing is supplied to the next process, the process of selecting one wafer each may become complicated.

In addition, in the manufacturing process of the fan-out package, as in the manufacturing method described in Patent Document 1, there is a case where the semiconductor wafer obtained by dicing is moved on the expansion tape. The aforementioned movement envisages a method of directly transferring a semiconductor wafer from a dicing tape to an expansion tape, and a method of transferring a semiconductor wafer from the dicing tape to another adhesive sheet, and then from the other adhesive sheet to the expansion tape. However, in any case, from the viewpoint of productivity, it is preferable to collectively transfer a plurality of semiconductor wafers. However, as in the dicing tape described in Patent Document 2, when a certain degree of adhesive force remains even after ultraviolet irradiation, a certain external force is required to separate the dicing tape and the semiconductor wafer, and it is necessary to separate the dicing tape from the semiconductor wafer. complex device. In addition, since a load is applied to the semiconductor wafer at the time of separation, a positional displacement and a wafer defect are likely to occur in the semiconductor wafer.

The present invention is constituted in view of the above-mentioned problems, and an object of the present invention is to provide that a plurality of wafers obtained by dicing a workpiece can be easily transferred to another adhesive sheet, and that the above-mentioned transfer can be effectively suppressed. A method of manufacturing a semiconductor device that generates wafer defects during printing. [In order to solve the problem]

The inventors of the present invention have discovered a method for manufacturing a semiconductor device by using an intumescent adhesive sheet having a base material and an adhesive layer and including intumescent particles in either layer, wherein specific processes (1) to (3) are involved. ) can solve the above problems. That is, the present invention relates to the following [1] to [11]. [1] A method of manufacturing a semiconductor device, comprising a base material (Y1) and an adhesive layer (X1), including intumescent particles in either layer, and a method of manufacturing a semiconductor device using an intumescent adhesive sheet (A). ,in There is a manufacturing method of a semiconductor device according to the following steps (1) to (3). Process (1): After attaching the workpiece to the adhesive layer (X1) of the adhesive sheet (A), cutting the workpiece to obtain a plurality of wafers on the adhesive layer (X1) . Process (2): Using an adhesive sheet (B) having a base material (Y2) and an adhesive layer (X2), on the surface opposite to the surface to which the adhesive layers (X1) of the plurality of chips are bonded Engineering of the adhesive layer (X2) of the sheet (B). Process (3): A process of expanding the expandable particles and separating the plurality of wafers and the adhesive sheet (A) attached to the adhesive sheet (B). [2] The method of manufacturing a semiconductor device according to the above [1], wherein the adhesive sheet (B) is an adhesive sheet for expansion, and further includes the following step (4A) after the step (3). Process (4A): The process of stretching and expanding the adhesive sheet (B) between the plurality of wafers attached to the adhesive sheet (B). [3] The method for manufacturing a semiconductor device according to the above [1], wherein the following process is further carried out using the adhesive sheet (C) for expansion having the base material (Y3) and the adhesive layer (X3): 4B-1)~(4B-3). Process (4B-1): The process of attaching the adhesive layer (X3) of the adhesive sheet (C) to the surface opposite to the surface to which the adhesive layers (X2) of the plurality of chips on the adhesive sheet (B) are bonded . Process (4B-2): The process of separating the adhesive sheet (B) from the plurality of chips attached to the adhesive sheet (C). Process (4B-3): The process of stretching and expanding the adhesive sheet (C) between the plurality of wafers attached to the adhesive sheet (C). [4] The method of manufacturing a semiconductor device according to the above [2] or [3], wherein the elongation at break of the adhesive sheet for expansion measured in the MD and CD directions at 23° C. is 100% above. [5] The method of manufacturing a semiconductor device according to any one of the above [1] to [4], wherein the expandable particles are thermally expandable particles having an expansion start temperature (t) of 60 to 270° C., and the process (3) The process of separating the plurality of wafers attached to the adhesive sheet (B) and the adhesive sheet (A) by heating the adhesive sheet (A). [6] The method for manufacturing a semiconductor device according to any one of the above [1] to [5], wherein the step (1) includes a process of stretching the adhesive sheet (A) after cutting the workpiece. [7] The method for manufacturing a semiconductor device according to any one of the above [1] to [6], wherein the intumescent particles adhere to the adhesive layer (X1) of the sheet (A) at 23° C. before expansion The adhesion is 0.1~10.0N/25mm. [8] The method of manufacturing a semiconductor device according to any one of the above [1] to [7], wherein the probe adhesion value on the surface of the substrate (Y1) of the adhesive sheet (A) is less than 50 mN/5 mmf. [9] The method of manufacturing a semiconductor device according to any one of the above [1] to [8], wherein the base material (Y1) of the adhesive sheet (A) is an expandable base material (Y1) containing the expandable particles. Y1-1). [10] The method for manufacturing a semiconductor device according to any one of the above [1] to [9], wherein the object to be processed is a semiconductor wafer. [11] The method of manufacturing a semiconductor device according to the above [10], which is a method of manufacturing a fan-out semiconductor device. Invention effect

According to the present invention, a plurality of wafers obtained by dicing a workpiece can be easily transferred to another adhesive sheet, and the production of a semiconductor device can be effectively suppressed from occurring during transfer. method.

In the present specification, the "active ingredient" refers to the components contained in the target composition, excluding the components of the dilution solvent. In addition, the mass average molecular weight (Mw) is a value in terms of standard polystyrene measured by a gel permeation chromatography (GPC) method, and specifically, it is a value measured according to the method described in the Examples.

In this specification, for example, "(meth)acrylic acid" is shown to mean both "acrylic acid" and "methacrylic acid", and other similar terms are also the same. In addition, about the ideal numerical range (for example, the range of content, etc.), the lower limit value and the upper limit value described in stages can be independently and combined. For example, from the description of "ideal is 10~90, more ideal is 30~60", the combination of "ideal lower limit value (10)" and "more ideal upper limit value (60)" is also "10~60". Can.

In this specification, "transfer of the wafer" means: after attaching the surface of the wafer attached to one of the adhesive sheets to the other adhesive sheet, and then separating the above-mentioned one of the adhesive sheets from the wafer, The operation of moving the wafer from one side of the adhesive sheet to the other side of the adhesive sheet.

The method of manufacturing a semiconductor device according to the present embodiment includes a substrate (Y1) and an adhesive layer (X1), and any layer contains expandable particles, and is a method of manufacturing a semiconductor device using an expandable adhesive sheet (A). , among which, there are those in the order of the following projects (1) to (3). Process (1): After attaching the workpiece to the adhesive layer (X1) of the adhesive sheet (A), cutting the workpiece to obtain a plurality of wafers on the adhesive layer (X1) . Process (2): Using an adhesive sheet (B) having a base material (Y2) and an adhesive layer (X2), on the surface opposite to the surface to which the adhesive layers (X1) of the plurality of chips are bonded Engineering of the adhesive layer (X2) of the sheet (B). Process (3): A process of expanding the expandable particles and separating the plurality of wafers and the adhesive sheet (A) attached to the adhesive sheet (B). Examples of workpiece systems used in this embodiment include semiconductor wafers, LEDs (Light Emitting Diodes), MEMS (Micro Electro Mechanical Systems), ceramic devices, semiconductor packages, and semiconductor devices having a plurality of devices. Those who are cut and processed in the manufacturing process such as others. In addition, in this specification, "wafer" means what means that the said to-be-processed object is individually sliced. Hereinafter, the pressure-sensitive adhesive sheet (A) used in the production method of the present embodiment will be described first, and then each production process including the steps (1) to (3) will be described.

[Adhesive Sheet (A)] The adhesive sheet (A) is an intumescent adhesive sheet having a base material (Y1) and an adhesive layer (X1), and any layer contains inflatable particles. Since the adhesive sheet (A) can firmly fix the workpiece through the adhesive surface of the adhesive layer (X1) before expanding the expandable particles, it can prevent the workpiece from being damaged in the cutting process of the workpiece. The position is shifted and the cutter is implemented with good workability. On the other hand, when separating the adhesive sheet (A) and the wafer obtained by dicing the workpiece, concavities and convexities are formed on the adhesive surface of the adhesive layer (X1) by expanding the expandable particles, and then the adhesive is The contact area between the adhesive surface of the layer (X1) and the chip is reduced, which can reduce the adhesive force compared with the conventional UV-curable dicing tape. As a result, a plurality of wafers obtained by dicing can be easily transferred to another adhesive sheet as a group without requiring a complicated manufacturing apparatus, and the occurrence of positional displacement of the wafer and occurrence of wafer defects can also be suppressed. By. In addition, when the adhesive sheet (A) is separated from the wafer, when the adhesive sheet (A) is partially heated, not all the wafers obtained by dicing are necessarily separated, and the obtained wafers may be selectively separated. part of the chip maker. Specifically, there is a form in which a plurality of wafers obtained by dicing are divided into a plurality of units, and each unit is transferred to another adhesive sheet.

1(a) and (b) are schematic cross-sectional views of the adhesive sheet 1a and the adhesive sheet 1b in one form of the adhesive sheet (A). In one aspect of the present invention, such as the adhesive sheets 1a, 1b, the substrate (Y1) is preferably an intumescent substrate (Y1-1) containing intumescent particles.

The adhesive sheet 1a shown in FIG. 1(a) has an adhesive layer (X1) on one side of the base material (Y1-1). The adhesive sheet 1a is configured by attaching a workpiece to the adhesive layer (X1), cutting the workpiece to obtain a plurality of wafers, and then separating them. When separating the adhesive sheet 1a and the wafer, by expanding the expandable particles in the base material (Y1-1), the unevenness is generated on the surface of the wafer bonded to the adhesive layer (X1), which can be easily performed. Separation at the interface of the adhesive layer (X1) and the wafer.

The adhesive sheet 1b shown in Fig. 1(b) is provided with an adhesive layer (X1) on one side of the substrate (Y1-1), and has a non-expandable substrate (Y1') on the other side . The adhesive sheet 1b is used in the same way as the adhesive sheet 1a, but in the case of expanding the expandable particles in the base material (Y1-1), the presence of the non-expandable base material (Y1') can prevent the expansion of the base material (Y1'). The unevenness on the surface of the material (Y1-1) on the side of the non-expandable base material (Y1') occurs, and through this, the unevenness on the surface on the side of the adhesive layer (X1) can be formed more efficiently.

The composition of the adhesive sheet (A) is not limited to the composition shown in FIGS. 1( a ) and ( b ), but for example, the composition of the base material ( Y1 ) ( ( Y1-1 in FIG. 1 )) and the adhesive Between the layers (X1), a configuration with other layers may be provided. However, from the viewpoint of being an adhesive sheet that can be separated with a slight force, it is preferable to have a structure in which the base material (Y1) and the adhesive layer (X1) are directly laminated. Moreover, the structure which has another adhesive bond layer may be sufficient as the surface on the opposite side to the adhesive bond layer (X1) of a base material (Y1). The adhesive sheet (A) is on the adhesive layer (X1), and may have a release material. The peeling material is suitably peeled and removed when the adhesive sheet (A) is used in the manufacturing method according to the present embodiment. The shape of the adhesive sheet (A) can take all shapes such as sheet shape, tape shape, and label shape.

(expandable particles) The pressure-sensitive adhesive sheet (A) is a layer of any one of the base material (Y1) and the pressure-sensitive adhesive layer (X1), and has a structure containing expandable particles. The swellable particles are those that expand themselves through external stimuli, form concavities and convexities on the adhesive surface of the adhesive layer (X1), and can reduce the adhesive force with the object to be adhered, and are not particularly limited. Examples of the expandable particle system include thermally expandable particles expanded by heating, energy linear expandable particles expanded by irradiation with energy rays, and the like, but thermally expandable particles are preferred from the viewpoints of generality and handling properties. .

The expansion start temperature (t) of the thermally expandable particles is desirably 60 to 270°C, more desirably 70 to 260°C, and still more desirably 80 to 250°C. However, in this specification, the expansion start temperature (t) of a heat-expandable particle means the value measured by the following method. [Method for measuring the expansion start temperature (t) of thermally expandable particles] An aluminum cup having a diameter of 6.0 mm (inner diameter 5.65 mm) and a depth of 4.8 mm was prepared, and 0.5 mg of thermally expandable particles to be measured were added, and a sample of an aluminum cap (diameter 5.6 mm, thickness 0.1 mm) was placed thereon. Using an active viscoelasticity measuring device, the height of the sample was measured from the upper part of the aluminum cover while a force of 0.01 N was applied via the presser. And, in the state where a force of 0.01 N is applied through the presser, from 20°C to 300°C, the heating rate is 10°C/min, and the displacement in the vertical direction of the presser is measured. The start temperature of the direction displacement is taken as the expansion start temperature (t).

The heat-expandable particles are preferably composed of an outer shell composed of a thermoplastic resin, and a microencapsulated foaming agent composed of the inner shell, which is enclosed in the outer shell, and vaporizes when heated to a specific temperature. Examples of thermoplastic resins constituting the outer shell of the microencapsulated foaming agent include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, and polypropylene. Nitrile, polyvinylidene chloride, polysilicon, etc.

Examples of the components contained in the casing include propane, butane, n-pentane, hexane, heptane, octane, nonane, decane, isobutane, isopentane, and isohexane. , isoheptane, isooctane, isononane, isodecane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, neopentane, dodecane, isodecane Dioxane, cyclododecane, cyclotridecane, hexylcyclohexene, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, isotridecane , 4-methyldodecane, isotetradecane, isopentadecane, isohexadecane, 2,2,4,4,6,8,8-heptamethylnonane, isoheptadecane, isohexadecane octadecane, isononadecane, 2,6,10,14-tetramethylpentadecane, cyclotridecane, heptylcyclohexane, n-octylcyclohexane, cyclopentadecane, nonyl Cyclohexane, decylcyclohexane, pentadecylcyclohexane, hexadecylcyclohexane, heptadecylcyclohexane, octadecylcyclohexane, etc. These inner-package components may be used alone or in combination of two or more. The expansion start temperature (t) of the heat-expandable particles can be adjusted by appropriately selecting the type of the inclusion component.

The maximum volume expansion rate when heated to a temperature higher than the thermal expansion start temperature (t) of the thermally expandable particles is ideally 1.5 to 100 times, more preferably 2 to 80 times, more preferably 2.5 to 60 times, and more. The ideal is 3 to 40 times.

The average particle diameter of the expandable particles at 23° C. before expansion is desirably 3 to 100 μm, more desirably 4 to 70 μm, still more desirably 6 to 60 μm, and still more desirably 10 to 50 μm. However, the mean particle diameter before expansion of the expandable particles refers to the volume median particle diameter (D ₅₀ ), which means that it is measured using a laser particle size analyzer (for example, manufactured by Malvern Corporation, product name "Mastersizer-3000"). , in the particle distribution of the expansive particles before expansion, the cumulative volume frequency calculated from the smaller of the particle diameters of the expansive particles before expansion is equivalent to 50% of the particle diameter.

The 90% particle diameter (D ₉₀ ) of the expandable particles at 23° C. before expansion is desirably 10 to 150 μm, more desirably 20 to 100 μm, still more desirably 25 to 90 μm, and still more desirably 30 to 80 μm. However, the 90% particle diameter (D ₉₀ ) of the expandable particles before expansion means that it is measured using a laser particle size analyzer (for example, manufactured by Malvern, product name "Mastersizer-3000"). In the particle size distribution of the expansive particles, the cumulative volume frequency calculated from the particle size of the expansible particle size before expansion is the smaller one is equivalent to 90% of the particle size.

The content of the expandable particles is preferably 1 to 40% by mass, more preferably 5 to 35% by mass, and more preferably 10% by mass relative to the total amount (100% by mass) of the active ingredient in the layer containing the expandable particles. ~30 mass %, still more preferably 15 to 25 mass %.

(Substrate (Y1)) The (substrate (Y1)) of the adhesive sheet (A) is a non-adhesive substrate. In the present invention, the determination of whether or not it is a non-adhesive substrate is for the surface of the target substrate, if the probe adhesion value measured according to JIS Z0237:1991 is less than 50mN/5mmf, the substrate The material is judged as "non-adhesive substrate". Here, the probe adhesion value on the surface of the substrate (Y1) used in this embodiment is usually less than 50mN/5mmf, but ideally less than 30mN/5mmf, more desirably less than 10mN/5mmf, and more desirably less than 5mN /5mmf. However, in this specification, the specific measurement method of the probe adhesion value on the surface of a base material (Y1) is based on the method described in the Example.

The thickness of the base material (Y1) is desirably 10 to 1000 μm, more desirably 20 to 500 μm, still more desirably 25 to 400 μm, and still more desirably 30 to 300 μm. However, in this specification, the thickness of a base material means the value measured by the method described in the Example.

The base material (Y1) can be formed from the resin composition (y1). Hereinafter, each component of the resin composition (y1) contained in the forming material of the base material (Y1) will be described.

[resin] The resin-based base material (Y1) contained in the resin composition (y1) is not particularly limited as long as it is a non-adhesive resin, and it may be a non-adhesive resin or an adhesive resin. That is, even if the resin contained in the resin composition (y1) is an adhesive resin, in the process of forming the base material (Y1) from the resin composition (y1), the adhesive resin and the polymerizable compound undergo a polymerization reaction. , the obtained resin becomes a non-adhesive resin, and the substrate (Y1) containing the resin can be non-adhesive.

The mass average molecular weight (Mw) of the resin contained in the resin composition (y1) is preferably 1,000 to 1,000,000, more preferably 1,000 to 700,000, and still more preferably 1,000 to 500,000. When the resin has a copolymer of two or more constituent units, the form of the copolymer is not particularly limited, and may be any of a block copolymer, a random copolymer, and a graft copolymer.

The content of the aforementioned resin is based on the total amount (100 mass %) of the active ingredients of the resin composition (y1), preferably 50 to 99 mass %, more preferably 60 to 95 mass %, and still more preferably 65 to 95 mass %. 90 mass %, more preferably 70 to 85 mass %.

It is preferable that the said resin contained in a resin composition (y1) contains 1 or more types chosen from acrylic urethane type resin and an olefin type resin. The urethane acrylate resin is preferably a polymeric urethane prepolymer (UP) and the urethane acrylate resin (U1) comprising a vinyl compound containing (meth)acrylate. However, these resin systems are particularly preferable from the viewpoint of swellability when the resin composition (y1) contains swellable particles.

[Acrylic urethane resin (U1)] As a urethane prepolymer (UP) which becomes the main chain of acrylic urethane resin (U1), the reaction product of a polyalcohol and a polyvalent isocyanate is mentioned. However, the urethane prepolymer (UP) is more preferably one obtained by subjecting it to a chain extension reaction using a chain extender.

Examples of polyols used as raw materials for urethane prepolymers (UP) include alkyl-type polyols, ether-type polyols, ester-type polyols, ester-amide-type polyols, and ester-ether-type polyols. Polyol, carbonate type polyol, etc. These polyols may be used alone or in combination of two or more. The polyalcohol-based diol used in this embodiment is preferable, and ester-type diol, alkyl-type diol and carbonate-type diol are more preferable, and ester-type diol and carbonate-type diol are even more preferable. good.

Examples of ester-type diols include those selected from the group consisting of 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, and the like. Alkylene glycol; ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol and other alkyl glycols; one or more of such glycols, and selected from phthalic acid, isophthalic acid, Terephthalic acid, naphthalene dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid , chloro bridged acid, maleic acid, fumaric acid, itaconic acid, cyclohexane-1,3-dicarboxylic acid, cyclohexane-1,4-dicarboxylic acid, hexahydrophthalic acid, hexahydroisophenylene A condensation polymer of one or more of dicarboxylic acids such as dicarboxylic acid, hexahydroterephthalic acid, and methylhexahydrophthalic acid, and anhydrides thereof. Specifically, polyethylene adipate diol, polybutene adipate diol, polycyclohexane adipate diol, polycyclohexane isophthalate diol, polyneopentyl Adipate glycol, polyethylene propylene adipate glycol, polyethylene butene adipate glycol, polybutene cyclohexane adipate glycol, polydiethylene adipate glycol, poly(polytetrafluoroethylene) Methylene ether) adipate diol, poly(3-methylpentadiene) diol, polyethylene azelaate diol, polyethylene sebacate diol, polybutene azelaate Diol, polybutene sebacate diol, polyneopentyl terephthalate diol, etc.

Examples of alkyl-type glycols include alkanes such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, and 1,6-hexanediol. Diols; Ethylene Glycol, Propylene Glycol, Diethylene Glycol, Dipropylene Glycol, etc. Alkyl Glycol; Polyethylene Glycol, Polypropylene Glycol, Polybutylene Glycol, etc. Polyolefin Glycol; Polytetramethylene Glycol, etc. The polyoxyalkylene glycol; and so on.

Examples of carbonate-type diols include 1,4-tetramethylene carbonate diol, 1,5-pentamethylene carbonate diol, and 1,6-hexamethylene carbonate diol. Alcohol, 1,2-Propylene Carbonate Diol, 1,3-Propene Carbonate Diol, 2,2-Dimethacrylate Diol, 1,7-Cycloheptane Carbonate Diol, 1,8 -Extyl-octyl carbonate diol, 1,4-cyclohexane carbonate diol, etc.

As a polyvalent isocyanate system which becomes a raw material of a urethane prepolymer (UP), aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate, etc. are mentioned. These polyvalent isocyanates may be used alone or in combination of two or more. In addition, these polyvalent isocyanates may also be trimethylolpropane adduct-type modifications, diurea-type modifications reacted with water, and isocyanurate-type modifications containing isocyanurate rings . Among these, the polyvalent isocyanate-based diisocyanate used in the present embodiment is preferably selected from 4,4'-diphenylmethane diisocyanate (MDI), 2,4-toluene diisocyanate (2,4 -TDI), 2, 6- toluene diisocyanate (2, 6- TDI), hexamethylene diisocyanate (HMDI), and 1 or more types of alicyclic diisocyanate are more preferable.

Examples of alicyclic diisocyanates include 3-isocyanatomethylene-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), 1,3-cyclopentane Alkane diisocyanate, 1,3-cyclohexanediisocyanate, 1,4-cyclohexanediisocyanate, methyl-2,4-cyclohexanediisocyanate, methyl-2,6-cyclohexanediisocyanate, etc. , but isophorone diisocyanate (IPDI) is preferred.

In the present embodiment, as a reaction product of a urethane prepolymer (UP)-based diol and a diisocyanate serving as the main chain of the acrylic urethane-based resin (U1), both ends have vinyl properties Unsaturated linear urethane prepolymers are preferred. As a method of introducing an ethylenically unsaturated group into both ends of the linear urethane prepolymer, a linear urethane prepolymer comprising a diol and a diisocyanate compound may be mentioned. A method of reacting terminal NCO groups with hydroxyalkyl (meth)acrylates. Examples of hydroxyalkyl (meth)acrylates include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate Acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, and the like.

It contains at least (meth)acrylate as a vinyl compound which becomes a side chain of acrylate urethane resin (U1). As the (meth)acrylate type, one or more kinds selected from the group consisting of alkyl (meth)acrylates and hydroxyalkyl (meth)acrylates are preferred, and alkyl (meth)acrylates and hydroxyalkyl (meth)acrylates are used in combination. Meth)acrylates are more preferred. In the case of using an alkyl (meth)acrylate and a hydroxyalkyl (meth)acrylate in combination, the ratio of the hydroxyalkyl (meth)acrylate to 100 parts by mass of the alkyl (meth)acrylate It is ideally 0.1 to 100 mass points, more ideally 0.5 to 30 mass points, still more ideally 1.0 to 20 mass points, and still more ideally 1.5 to 10 mass points.

The carbon number system of the alkyl group which the alkyl (meth)acrylate has is desirably 1-24, more desirably 1-12, still more desirably 1-8, and still more desirably 1-3. Examples of hydroxyalkyl (meth)acrylates include the same hydroxyalkyl (meth)acrylates used at both ends of the linear urethane prepolymer described above for introducing ethylenic unsaturation. composition.

Examples of vinyl compounds other than (meth)acrylates include aromatic hydrogen-based vinyl compounds such as styrene, α-methylstyrene, and vinyltoluene; methyl vinyl ether, and ethyl vinyl. vinyl ethers such as vinyl ethers; vinyl acetate, vinyl propionate, (meth)acrylonitrile, N-vinylpyrrolidone, (meth)acrylic acid, maleic acid, fumaric acid, itaconic acid, methyl(propylene) The polar group of amide) etc. contains monomers; etc. These systems may be used alone or in combination of two or more.

The content of the (meth)acrylate in the vinyl compound is preferably 40 to 100 mass %, more preferably 65 to 100 mass %, and more preferably 40 to 100 mass % with respect to the total amount (100 mass %) of the vinyl compound. It is 80-100 mass %, and it is still more preferable that it is 90-100 mass %. The total content of the alkyl (meth)acrylate and hydroxyalkyl (meth)acrylate in the vinyl compound is preferably 40 to 100% by mass relative to the total amount (100% by mass) of the vinyl compound. More preferably, it is 65 to 100 mass %, still more preferably 80 to 100 mass %, and still more preferably 90 to 100 mass %.

The acrylic urethane resin (U1) used in this embodiment is obtained by polymerizing a mixed urethane prepolymer (UP) and a (meth)acrylate-containing vinyl compound. . In this polymerization, it is preferable to carry out more radical initiators.

In the acrylic urethane resin (U1) used in this embodiment, as the structural unit (u11) derived from the urethane prepolymer (UP) and the structural unit (u12) derived from the vinyl compound The content ratio [(u11)/(u12)] is based on the mass ratio, ideally 10/90~80/20, more ideally 20/80~70/30, and more ideally 30/70~60/40, Another ideal is 35/65~55/45.

[Olefin-based resin] As the resin contained in the resin composition (y1), the optimum olefin-based resin is a polymer having at least a structural unit derived from an olefin monomer. The α-olefin having 2 to 8 carbon atoms in the olefin monomer system is preferable, and specifically, ethylene, propylene, butene, isobutylene, 1-hexene and the like can be mentioned. Among these, ethylene and propylene are preferred.

Specific examples of olefin-based resins include: ultra-low density polyethylene (VLDPE, density: 880 kg/m ³ or more and less than 910 kg/m ³ ), low density polyethylene (LDPE, density: 910 kg/m ³ or more) , less than 915kg/m ³ ), medium density polyethylene (MDPE, density: 915kg/m ³ or more, less than 942kg/m ³ ), high density polyethylene (HDPE, density: 942kg/m ³ or more), linear low Polyethylene resin such as density polyethylene; polypropylene resin (PP); polybutene resin (PB); ethylene-propylene copolymer; olefin-based elastomer (TPO); poly(4-methyl-1-pentene) (PMP); ethylene-vinyl acetate copolymer (EVA); ethylene-vinyl alcohol copolymer (EVOH); Wait.

In the present embodiment, the olefin-based resin is a modified olefin-based resin further subjected to one or more kinds of modification selected from acid modification, hydroxyl group modification, and acrylic modification.

For example, examples of acid-denatured olefin-based resins obtained by acid-denaturing olefin-based resins include those obtained by graft-polymerizing unsaturated carboxylic acids or their acid anhydrides to the above-mentioned non-denatured olefin-based resins. denatured polymers. As the above-mentioned unsaturated carboxylic acid or its anhydride, for example, maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaric acid, tetrahydrophthalic acid, aconitic acid, (meth)acrylic acid, Maleic anhydride, itaconic anhydride, phthalic anhydride, citraconic anhydride, aconitic anhydride, norbornene dihydroxy anhydride, tetrahydrophthalic anhydride, etc. However, an unsaturated carboxylic acid or its acid anhydride system can also be used individually or in combination of 2 or more types.

Examples of acrylic-modified olefin-based resins that are acrylic-modified olefin-based resins include the above-mentioned non-modified olefin-based resins in the main chain, and alkyl (meth)acrylates as side chains. A denatured polymer formed by graft polymerization. The carbon number system of the alkyl group which the above-mentioned alkyl (meth)acrylate has is desirably 1-20, more desirably 1-16, and still more desirably 1-12. Examples of the above-mentioned alkyl (meth)acrylates include the same compounds as those that can be selected as the monomer (a1') to be described later.

Examples of hydroxyl-modified olefin-based resins obtained by denaturing olefin-based resins with hydroxyl groups include the above-mentioned non-denatured olefin-based resins in the main chain, obtained by graft-polymerizing hydroxyl compounds. denatured polymer. Examples of the above-mentioned hydroxyl group-containing compound system include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, Hydroxyalkyl (meth)acrylates of 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.; vinyl alcohol , unsaturated alcohols such as allyl alcohol, etc.

[Resins other than acrylic-urethane-based resins and olefin-based resins] In the present embodiment, the resin composition (y1) may contain resins other than the acrylic polyurethane-based resin and the olefin-based resin within a range that does not impair the effects of the present invention. Examples of such resins include vinyl-based resins such as polyvinyl chloride, polyvinylidene chloride, and polyvinyl alcohol; polyethylene terephthalate, polybutylene terephthalate, and polynaphthalene. Polyester resins such as ethylene dicarboxylate; polystyrene; acrylonitrile-butadiene-styrene copolymers; cellulose triacetate; polycarbonate; not suitable for acrylic polyurethane resins Polyurethane; polyether; polydiether ketone; polyether ash; polyphenylene sulfide; polyetherimide; polyimide resin such as polyimide; polyamide resin; acrylic resin; fluorine resin Wait. The content ratio of the resin other than the propylene-urethane-based resin and the olefin-based resin is preferably less than 30 parts by mass with respect to 100 parts by mass of the total amount of the resin contained in the resin composition (y1), and more preferably Less than 20 quality points, more ideally less than 10 quality points, still more ideal as less than 5 quality points, and still more ideal as less than 1 quality point.

It is preferable that the resin composition (y1) contains expandable particles. When the adhesive sheet (A) contains expansible particles, not the adhesive layer, on the substrate (Y1) with high elastic modulus, the adhesive layer (X1) of the workpiece represented by the semiconductor wafer is placed ) thickness adjustment, adhesive force, viscoelastic rate control, etc., the degree of freedom of design is improved. The positional shift of the wafer obtained by this and the generation|occurence|production of a wafer defect can be suppressed. Furthermore, in the case of using the adhesive sheet (A), since the wafer is placed on the adhesive surface of the adhesive layer (X1), the substrate (Y1) containing the expandable particles and the wafer are not in direct contact. In this way, a part of the adhesive layer that suppresses the residues and large deformation from the expansive particles adheres to the wafer, and the uneven shape formed on the adhesive layer is transferred to the wafer, so that the wafer can be provided with cleanliness. in the next project. The optimum content of the expandable particles is as described above.

The resin composition (y1) may contain an additive for a base material as necessary within a range that does not impair the effects of the present invention. As an additive system for base materials, an ultraviolet absorber, a light stabilizer, an oxidation inhibitor, an antistatic agent, a slip agent, a release agent, a coloring agent, etc. are mentioned, for example. Each of these base material additives may be used alone, or two or more of them may be used in combination. When these additives for substrates are contained, the content of each additive for substrates is desirably 0.0001 to 20 parts by mass, more desirably 0.001 to 100 parts by mass of the resin in the resin composition (y1). 10 quality points.

[Solvent-free resin composition (y1')] As one form of the resin composition (y1) used in this embodiment, an oligomer having an ethylenically unsaturated group having a mass average molecular weight (Mw) of 50,000 or less, and an energy ray polymerizable monomer can be mentioned. , and the solvent-free resin composition (y1') that is prepared by preparing the above-mentioned expandable particles without the preparation of a solvent. In the solvent-free resin composition (y1'), although no solvent is prepared, the energy ray polymerizable monomer contributes to the above-mentioned structure of improving the plasticity of the oligomer. For the coating film formed from the solvent-free resin composition (y1'), the substrate (Y1) can be obtained by irradiating the energy ray. The type, shape, and blending amount (content) of the expandable particles to be blended in the solvent-free resin composition (y1') are as described above.

The mass-average molecular weight (Mw) of the oligomer contained in the solvent-free resin composition (y1') is 50,000 or less, preferably 1,000 to 50,000, more preferably 2,000 to 40,000, and more preferably 3,000 to 35,000 , and more ideally 4000~30000.

Among the resins contained in the above-mentioned resin composition (y1) as the oligomers, those having an ethylenically unsaturated group with a mass average molecular weight (Mw) of 50,000 or less may be used, but the above-mentioned urethanes Prepolymer (UP) is preferred. However, as the oligomer system, a modified olefin resin or the like having an ethylenically unsaturated group can also be used.

In the solvent-free resin composition (y1'), the total content of the oligomer and the energy ray polymerizable monomer is preferably the total amount (100% by mass) of the solvent-free resin composition (y1'). It is 50 to 99 mass %, more preferably 60 to 95 mass %, still more preferably 65 to 90 mass %, and still more preferably 70 to 85 mass %.

Examples of the energy ray polymerization monomer system include isobornyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentyl (meth)acrylate, ethylene glycol diacrylate Alicyclic polymerizable compounds such as cyclopentenyl ether (meth)acrylate, cyclohexyl (meth)acrylate, adamantane (meth)acrylate, tricyclodecane acrylate, etc.; phenylhydroxypropyl Aromatic polymerizable compounds such as acrylates, benzyl acrylates, phenol ethylene oxide modified acrylates, etc.; ethylene oxide (meth)acrylates, morphofuraline acrylates, N-vinylpyrrolidone, N-vinyl Branched complex cyclic polymerizable compounds such as caprolactam, etc. These energy ray polymerization monomer systems may be used alone or in combination of two or more.

In the solvent-free resin composition (y1'), the content ratio of the oligomer and the energy ray polymerizable monomer (the oligomer/energy ray polymerizable monomer) is a mass ratio, preferably 20/80 ~90/10, more ideally 30/70~85/15, still more ideally 35/65~80/20.

In the present embodiment, it is preferable that the solvent-free resin composition (y1') is prepared by further blending a photopolymerization initiator. From those containing a photopolymerization initiator, the curing reaction can be sufficiently advanced by irradiation of relatively low-energy energy rays.

Examples of the photopolymerization initiator system include: 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin cake ether, benzyl phenyl sulfide, tetrakis Methylthiuram disulfide, azobisisobutyronitrile, dibenzyl, diacetyl, 8-anthraquinone, etc. Each of these photopolymerization initiators may be used alone, or two or more of them may be used in combination.

The compounding amount of the photopolymerization initiator is preferably 0.01 to 5 parts by mass, more preferably 0.01 to 4 parts by mass, and more preferably 0.01 to 4 parts by mass with respect to the total amount (100 parts by mass) of the aforementioned oligomers and energy ray polymerizable monomers. 0.02~3 quality points.

From the viewpoint of improving the interlayer adhesion between the substrate (Y1) and other layers to be laminated, the surface of the substrate (Y1) is subjected to surface treatment by an oxidation method, an unevenness method, etc. Adjust processing, easy to follow processing can also be. Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromic acid treatment (wet treatment), hot air treatment, ozone, and ultraviolet irradiation treatment, and examples of the concavo-convex method include sandblasting. Treatment method, solvent treatment method, etc.

[Storage elastic modulus of base material (Y1)] The storage elastic modulus E' (23) at 23°C of the base material (Y1) is preferably 1.0×10 ⁶ Pa or more, more preferably 5.0×10 ⁶ to 5.0×10 ¹² Pa, still more ideally 1.0×10 ⁷ ~1.0×10 ¹² Pa, still more ideally 5.0×10 ⁷ ~1.0×10 ¹¹ Pa, still more ideally 1.0×10 ⁸ ~1.0×10 ¹⁰ Pa . When the storage elastic modulus E' (23) of the base material (Y1) is within the above-mentioned range, the occurrence of positional displacement of the workpiece during dicing and the occurrence of positional displacement during wafer transfer can be suppressed. However, in this specification, the storage elastic modulus E' of the base material (Y1) at a specific temperature means the value measured by the method described in the Example.

When the base material (Y1) contains heat-expandable particles as the expandable particles in the expandable base material (Y1-1), in the expansion start temperature (t) of the heat-expandable particles, the expandable base material (Y1- 1) The storage elastic modulus E'(t) is preferably 1.0×10 ⁷ Pa or less. At the temperature at which the heat-expandable particles are expanded, the expandable substrate (Y1-1) is easily deformed with the volume expansion of the heat-expandable particles, and the adhesive layer (X1) tends to form irregularities. surface. Thereby, it can be separated from the wafer by a small external force. From the above viewpoints, the storage elastic modulus E'(t) of the intumescent base material (Y1-1) is more preferably 9.0×10 ⁶ Pa or less, still more preferably 8.0×10 ⁶ Pa or less, and still more preferably 6.0 ×10 ⁶ Pa or less, and still more preferably 4.0 × 10 ⁶ Pa or less. In addition, from the viewpoint of suppressing the flow of the thermally expandable particles that expand, improving the shape retention of the unevenness formed on the adhesive surface of the adhesive layer (X1), and further improving the separability, the intumescent substrate (Y1-1) The storage elastic modulus E'(t) is desirably 1.0×10 ³ Pa or higher, more desirably 1.0×10 ⁴ Pa or higher, and still more desirably 1.0×10 ⁵ Pa or higher.

(Non-expandable substrate (Y1')) The adhesive sheet (A) may have an adhesive layer (X1) on one side of the substrate (Y1-1), and may have a non-expandable substrate (Y1') on the other side. The "non-expandable base material" in this specification is defined as a volume change rate calculated from the following formula of less than 5% by volume when processed under conditions in which the expandable particles contained in the adhesive sheet (A) are expanded. By. Volume change rate (%) = (volume of the layer before treatment - volume of the layer before treatment) / volume of the layer before treatment × 100 The volume change rate (%) of the non-expandable base material (Y1') calculated from the above formula is desirably less than 2 vol %, more desirably less than 1 vol %, more desirably less than 0.1 vol %, and still more desirable. Ideally, it is less than 0.01% by volume. The conditions for the expansion of the expansible particles are the conditions in which the expansive particles are thermally expansible particles, and are heat-treated for 3 minutes at the expansion start temperature (t). The non-expandable base material (Y1') may contain expandable particles, but the smaller the content, the better. For the total mass (100% by mass) of the non-expandable base material (Y1'), usually , less than 3 mass %, ideally less than 1 mass %, more desirably less than 0.1 mass %, still more desirably less than 0.01 mass %, still more desirably less than 0.001 mass %, and not containing expansive particles is the best .

Examples of materials for forming the non-expandable base material (Y1') include paper, resin, metal, and the like. Examples of paper materials include thin-leaf paper, medium-quality paper, high-quality paper, impregnated paper, coated paper, art paper, sulfuric acid paper, cellophane paper, and the like. Examples of resin systems include polyolefin resins such as polyethylene and polypropylene; polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, ethylene-vinyl acetate copolymers, and ethylene-vinyl alcohol copolymers and the like. Vinyl resin; Polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, etc.; polystyrene; acrylonitrile-butadiene-styrene copolymer cellulose triacetate; polycarbonate; urethane resin such as polyurethane, acrylic modified polyurethane, etc.; polymethylpentene; Polyphenylene sulfide; polyetherimide; polyimide resins such as polyimide; polyimide resins; acrylic resins; fluorine resins, etc. As a metal system, aluminum, tin, chromium, titanium etc. are mentioned, for example. These forming materials may be composed of one type, or two or more types may be used in combination. The non-expandable base material (Y1') which uses two or more kinds of forming materials in combination includes a structure in which a thermoplastic resin such as polyethylene is used to laminate a paper material, and a resin film or sheet containing the resin is formed on the surface of the resin film or sheet. The composition of the metal film, etc. However, as a method of forming the metal layer, for example, a method of vapor-depositing the above-mentioned metal by a PVD method such as vacuum evaporation, sputtering, and ion plating, or a method of attaching the above-mentioned metal using a general adhesive can be mentioned. The method of metal foil, etc.

In the case where the adhesive sheet (A) has a non-expandable base material (Y1'), before expanding the expandable particles, the thickness ratio of the expandable base material (Y1-1) to the non-expandable base material (Y1') [ (Y1-1)/(Y1')] is desirably 0.02 to 200, more desirably 0.03 to 150, and still more desirably 0.05 to 100.

From the viewpoint of improving the interlayer adhesion between the non-expandable base material (Y1') and other layers as a laminate, when the non-expandable base material (Y1') contains a resin, the non-expandable base material (Y1') ), similarly to the above-mentioned base material (Y1), surface treatment by oxidation method, unevenness method, etc., infiltration treatment, and easy-bonding treatment may be applied. When the non-expandable base material (Y1') contains a resin, it may be contained in the resin composition (y1) together with the resin, and the above-mentioned additives for base materials may be contained.

(Adhesive layer (X1)) The adhesive layer (X1) is an adhesive layer. The adhesive layer (X1) contains an adhesive resin, and may also contain additives for adhesives such as a crosslinking agent, an adhesive imparting agent, a polymerizable compound, and a polymerization initiator as necessary.

The adhesive force of the adhesive surface of the adhesive layer (X1) is at 23°C before the expansion of the intumescent particles, ideally 0.1~10.0N/25mm, more preferably 0.2~8.0N/25mm, and more preferably 0.4~6.0 N/25mm, and more preferably 0.5~4.0N/25mm. When the aforementioned adhesive force is 0.1 N/25mm or more, the workpiece can be sufficiently fixed, and the occurrence of positional displacement of the workpiece during cutting can be suppressed. On the other hand, when the adhesive force is 10.0 N/25 mm or less, separation from the wafer can be easily performed with only a slight force. However, the above-mentioned adhesive force means the value measured by the method described in the Example.

The shear storage modulus G'(23) of the adhesive layer (X1) is at 23°C, ideally 1.0×10 ⁴ ~1.0×10 ⁸ Pa, more ideally 5.0×10 ⁴ ~5.0×10 ⁷ Pa, More preferably, it is 1.0×10 ⁵ to 1.0×10 ⁷ Pa. When the shear force storage modulus G' (23) of the adhesive layer (X1) is 1.0×10 ⁴ Pa or more, the positional displacement of the wafer can be prevented during separation from the wafer. On the other hand, when the shear storage modulus G' (23) of the adhesive layer (X1) is 1.0×10 ⁸ Pa or less, the concavities and convexities of the expandable particles through expansion are easily formed on the adhesive surface, and only a slight the force of separation easily. The adhesive sheet (A) is an adhesive sheet with a plurality of adhesive layers, and the shear force storage modulus G' (23) of the adhesive layer attached to the chip is preferably within the above range, which is better than that of the substrate (Y1 ) The shear storage modulus G' (23) of all the adhesive layers on the wafer side is preferably within the above range. However, in this specification, the shear storage modulus G' (23) of the adhesive layer (X1) means the value measured by the method described in the Example.

The thickness of the adhesive layer (X1) is from the viewpoint of finding superior adhesive force, and from the viewpoint that the expansion of the intumescent particles in the heat-treated intumescent base material is easy to form unevenness on the surface of the formed adhesive layer, Ideally, it is 1 to 60 μm, more preferably 2 to 50 μm, still more preferably 3 to 40 μm, and still more preferably 5 to 30 μm.

The ratio of the thickness of the substrate (Y1) to the thickness of the adhesive layer (X1) (substrate (Y1)/adhesive layer (X1)) is from the viewpoint of preventing the positional shift of the wafer, at 23°C , desirably 0.2 or more, more desirably 0.5 or more, still more desirably 1.0 or more, and sometimes more desirably 5.0 or more, in addition, as the adhesiveness that can be easily separated with only a slight force when separating From the viewpoint of flakes, it is desirably 1,000 or less, more desirably 200 or less, still more desirably 60 or less, and still more desirably 30 or less. The thickness of the adhesive layer (X1) means the value measured by the method described in the examples.

The adhesive layer (X1) can be formed from the adhesive composition (x1) containing an adhesive resin. Hereinafter, each component which can be contained in an adhesive composition (x1) is demonstrated.

[Adhesive resin] The adhesive resin of the forming material of the adhesive layer (X1) is preferably a polymer having adhesiveness alone and a mass average molecular weight (Mw) of 10,000 or more. The mass average molecular weight (Mw) of the adhesive resin is more preferably 10,000 to 2,000,000, more preferably 20,000 to 1,500,000, and still more preferably 30,000 to 1,000,000 from the viewpoint of improving the adhesive force.

Examples of adhesive resins include acrylic resins, urethane resins, rubber-based resins such as polyisobutylene-based resins, polyester-based resins, olefin-based resins, polysiloxane-based resins, and polyvinyl ethers. resin, etc. These adhesive resins may be used alone or in combination of two or more. In addition, when these adhesive resins are copolymers having two or more constituent units, the form of the copolymers is not particularly limited, and may be block copolymers, random copolymers, and graft copolymers. any of things.

The adhesive resin may also be an energy ray-curable adhesive resin in which a polymerizable function is introduced based on the side chain of the above-mentioned adhesive resin. As said polymerizable functional group system, a (meth)acryloyl group, a vinyl group, etc. are mentioned. Moreover, as an energy ray system, an ultraviolet-ray, an electron beam, etc. are mentioned, However, an ultraviolet-ray is preferable.

The content of the adhesive resin is preferably 30 to 99.99% by mass, more preferably 40 to 99.95% by mass, and more preferably 50% by mass relative to the total amount (100% by mass) of the active ingredient in the adhesive composition (x1). ~99.90 mass %, still more preferably 55 to 99.80 mass %, still more preferably 60 to 99.50 mass %. However, in the following descriptions in this specification, "the content of each component with respect to the total amount of the active ingredients of the adhesive composition" is the same as "each component in the adhesive layer formed from the adhesive composition" content" is synonymous.

Adhesive resin is from the viewpoint of being an adhesive sheet that is easy to form unevenness on the adhesive surface due to the expansion of expandable particles on the adhesive surface during separation, and at the same time that superior adhesive force was found, and those containing acrylic resin are: good. The content ratio of the acrylic resin in the adhesive resin is preferably 30 to 100% by mass, and more preferably 50% by mass with respect to the total amount (100% by mass) of the adhesive resin contained in the adhesive composition (x1). ~100 mass %, still more preferably 70 to 100 mass %, still more preferably 85 to 100 mass %.

[acrylic resin] It can be used as an adhesive resin. Examples of acrylic resins include polymers derived from a structural unit derived from an alkyl (meth)acrylate having a straight or branched alkyl group, and a polymer derived from a cyclic alkyl group. A polymer having a structural unit of (meth)acrylate having a structural unit like an alkyl (meth)acrylate (a1') (hereinafter, also referred to as "monomer (a1')") (a1) and the acrylic copolymer (A1) derived from the functional group containing the structural unit (a2) of the monomer (a2') (hereinafter, also referred to as "monomer (a2')") are more preferable.

The carbon number of the alkyl group of the monomer (a1') is preferably 1 to 24, more preferably 1 to 12, still more preferably 2 to 10, and still more preferably 4, from the viewpoint of improving the adhesive properties. ~8. However, the alkyl group possessed by the monomer (a1') may be a straight-chain alkyl group or a branched-chain alkyl group. As the monomer (a1') system, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate and the like. These monomers (a1') may be used alone or in combination of two or more. The monomers (a1') are preferably butyl (meth)acrylate and 2-ethylhexyl (meth)acrylate. The content of the structural unit (a1) is preferably 50 to 99.9 mass %, more preferably 60 to 99.0 mass %, and more preferably 50 to 99.9 mass % with respect to all the structural units (100 mass %) of the acrylic copolymer (A1). It is 70-97.0 mass %, and it is still more preferable that it is 80-95.0 mass %.

Examples of the functional group system possessed by the monomer (a2') include a hydroxyl group, a carboxyl group, an amino group, an epoxy group, and the like. That is, examples of the monomer (a2') system include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, an epoxy group-containing monomer, and the like. These monomers (a2') may be used alone or in combination of two or more. Among these, as the monomer (a2'), a hydroxyl group-containing monomer and a carboxyl group-containing monomer are preferable. Examples of the hydroxyl group-containing monomer system include the same constitution as the above-mentioned hydroxyl group-containing compound. Examples of the carboxyl group-containing monosystem include ethylenically unsaturated monocarboxylic acids such as (meth)acrylic acid and crotonic acid; ethylenically unsaturated dicarboxylic acids such as fumaric acid, itaconic acid, maleic acid, and citraconic acid. Carboxylic acid and its anhydride, 2-(acryloyloxy) ethyl succinate, 2-carboxyethyl (meth)acrylate, etc. The content of the structural unit (a2) is preferably 0.1 to 40 mass %, more preferably 0.5 to 35 mass %, and more preferably 0.1 to 40 mass % with respect to all the structural units (100 mass %) of the acrylic copolymer (A1). It is 1.0-30 mass %, and it is still more preferable that it is 3.0-25 mass %.

The acrylic copolymer (A1) may further have a structural unit (a3) derived from a monomer (a3') other than the monomers (a1') and (a2'). However, in the acrylic copolymer (A1), the content of the structural units (a1) and (a2) is preferably 70 to 100 with respect to all the structural units (100 mass %) of the acrylic copolymer (A1). The mass % is more preferably 80 to 100 mass %, still more preferably 90 to 100 mass %, and still more preferably 95 to 100 mass %.

Examples of the monomer (a3') include: olefins such as ethylene, propylene, and isobutylene; halogenated olefins such as vinyl chloride and vinylidene chloride; butadiene, isoprene, and isoprene. Diene monomers such as; with cyclohexyl (meth)acrylate, benzophenone (meth)acrylate, isobornyl (meth)acrylate, dicyclopentyl (meth)acrylic acid Ester, dicyclopentene (meth)acrylate, ethylene glycol dicyclopentenyl ether (meth)acrylate, imide (meth)acrylate, etc. (meth)acrylate of cyclic structure ; Styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, (meth)acrylamide, (meth)acrylonitrile, (meth)acrylomorpholine, N- Vinylpyrrolidone, etc.

The acrylic copolymer (A1) may be an energy ray hardening type acrylic copolymer based on a side chain introduced with a polymerizable function. The polymerizable functional group and the energy ray are as described above. However, the polymerizable functional group is composed of an acrylic copolymer having the above-mentioned structural units (a1) and (a2), and a substituent having a functional group that can be bonded to the functional group contained in the structural unit (a2) of the acrylic copolymer. Those reacting with the compound of the polymerizable functional group can be introduced. As said compound system, isocyanoethyl (meth)acrylate, (meth)acryloyl isocyanate, glycidyl (meth)acrylate etc. are mentioned, for example.

The mass average molecular weight (Mw) of the acrylic resin is preferably 100,000 to 1.5 million, more preferably 200,000 to 1.3 million, still more preferably 350,000 to 1.2 million, and still more preferably 500,000 to 1.1 million.

[Crosslinking agent] When the adhesive composition (x1) is an adhesive resin containing the functional group of the acrylic copolymer (A1) as described above, it is preferable that it further contains a crosslinking agent. The cross-linking agent reacts with the adhesive resin having a functional group, and the functional group is used as a cross-linking origin to cross-link the composition of the adhesive resins. As a crosslinking agent system, an isocyanate type crosslinking agent, an epoxy type crosslinking agent, an aziridine type crosslinking agent, a metal chelate type crosslinking agent etc. are mentioned, for example. These crosslinking agents may be used alone or in combination of two or more. Among these cross-linking agents, isocyanate-based cross-linking agents are preferable from the viewpoints of improving the cohesive force and increasing the adhesive force, and from the viewpoints of easy availability. The content of the crosslinking agent is appropriately adjusted according to the number of functional groups of the adhesive resin, but for 100 parts by mass of the adhesive resin having functional groups, it is ideally 0.01 to 10 parts by mass, more preferably 0.01 to 10 parts by mass. It is 0.03 to 7 mass points, and more preferably 0.05 to 5 mass points.

[Adhesion imparting agent] The adhesive composition (x1) may further contain an adhesive imparting agent from the viewpoint of further improving the adhesive force. In this specification, "adhesion imparting agent" refers to a component that supplementally improves the adhesive force of the above-mentioned adhesive resin, and the mass average molecular weight (Mw) refers to an oligomer of less than 10,000, which is related to the above-mentioned adhesive resin. differentiated composition. The mass average molecular weight (Mw) of the adhesion imparting agent is desirably 400-10,000, more desirably 500-8,000, and still more desirably 800-5,000.

Examples of the tackifier system include rosin-based resins, terpene-based resins, styrene-based resins, pentene copolymerized by thermal decomposition of naphtha, isoprene, piperine, 1,3 - C5-based petroleum resins obtained from C5 fractions of cyclopentadiene, etc., C9-based petroleum resins obtained by copolymerization of indene generated by thermal decomposition of naphtha, C9 fractions of ethylene toluene, etc., and hydrogenation of these The hydrogenated resin, etc.

The softening point of the adhesion imparting agent is desirably 60 to 170°C, more desirably 65 to 160°C, and still more desirably 70 to 150°C. However, in this specification, the "softening point" of an adhesion-imparting agent means the value measured based on JISK2531. The adhesion imparting agent may be used alone, or two or more kinds of different softening points and structures may be used in combination. In the case of using two or more types of adhesion-imparting agents, it is preferable that the weighted average of the softening points of these plural adhesion-imparting agents falls within the above-mentioned range.

The content of the tackifier is preferably 0.01 to 65% by mass, more preferably 0.05 to 55% by mass, and more preferably 0.1 with respect to the total amount (100% by mass) of the active ingredient in the adhesive composition (x1). ~50 mass %, still more preferably 0.5 to 45 mass %, still more preferably 1.0 to 40 mass %.

[Photopolymerization initiator] In the present embodiment, the adhesive composition (x1) is used as the adhesive resin, and when it contains an energy ray-curable adhesive resin, it is preferable that it further contains a photopolymerization initiator. With the adhesive composition containing the energy-ray-curable adhesive resin and the photopolymerization initiator, the curing reaction can be sufficiently advanced by irradiation with relatively low-energy energy rays, and the adhesive force can be adjusted to the desired level. rangers. However, as a photoinitiator system, the thing similar to the structure mix|blended with the said non-solvent-type resin composition (y1) is mentioned. The content of the photopolymerization initiator is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, and still more preferably 0.05 to 2 parts by mass with respect to 100 parts by mass of the energy ray-curable adhesive resin.

[Additives for Adhesives] In the present embodiment, the adhesive composition (x1) of the material for forming the adhesive layer (X1) is within a range that does not impair the effects of the present invention, and other than the above-mentioned additives, adhesives used in general adhesives are included. Additives can also be used. Examples of such an additive system for adhesives include oxidation inhibitors, softeners (plasticizers), rust inhibitors, pigments, dyes, retarders, reaction accelerators (catalysts), and ultraviolet absorbers. However, each of these additives for adhesives may be used alone, or two or more of them may be used in combination. When these additives for adhesives are contained, the content of each additive for adhesives is preferably 0.0001 to 20 parts by mass, more preferably 0.001 to 10 parts by mass, based on 100 parts by mass of the adhesive resin. The adhesive layer (X1) may contain expandable particles. The content of the adhesive resin is preferably 5 parts by mass or less, more preferably 2 parts by mass or less, and most preferably not contained, relative to 100 parts by mass of the adhesive resin.

(peeling material) Examples of the release material system used arbitrarily include the use of a release sheet as a double-sided release treatment, a release sheet as a single-side release treatment, and the like, and a configuration in which a release agent is applied to a release material base material, and the like. Examples of the base material for the release material include paper such as high-quality paper, cellophane, and kraft paper; polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene naphthalate Polyester resin films such as diester resins, plastic films such as polypropylene resins, polyolefin resin films such as polyethylene resins; etc. Examples of release agents include silicone-based resins, polyolefin-based resins, isoprene-based resins, rubber-based elastomers such as butadiene-based resins, long-chain alkyl-based resins, and alkyd-based resins. resin, fluorine resin, etc. The thickness of the peeling material is not particularly limited, but is preferably 10 to 200 μm, more preferably 25 to 170 μm, and still more preferably 35 to 80 μm.

<The manufacturing method of the adhesive sheet (A)> Although it does not specifically limit as a manufacturing method of an adhesive sheet (A), For example, the manufacturing method (I) which has the following process (Ia) and (Ib) is mentioned. Process (Ia): On the peeling-treated surface of the release material, the resin composition (y1) of the forming material of the base material (Y1) is applied to form a coating film, and the coating film is dried or UV-cured to form the base material (Y1) the project. Process (Ib): On the surface of the formed base material (Y1), apply the adhesive composition (x1) of the forming material of the adhesive layer (X1) to form a coating film, and dry the coating film to form an adhesive Layer (X1) works.

As another manufacturing method of an adhesive sheet (A), the manufacturing method (II) which has the following process (IIa) - (IIc) is mentioned, for example. Process (IIa): On the peeling-treated surface of the release material, the resin composition (y1) of the forming material of the base material (Y1) is applied to form a coating film, and the coating film is dried or UV-cured to form the base material (Y1) the project. Process (IIb): The process of coating the adhesive composition (x1) of the forming material of the adhesive layer (X1) on the peeling treatment surface of the release material to form a coating film, drying the coating film, and forming the adhesive layer. Process (IIc): The process of adhering to the surface of the substrate (Y1) formed in the process (IIa) and the surface of the adhesive layer (X1) formed in the process (IIb).

In the above-mentioned production methods (I) and (II), the resin composition (y1) and the adhesive composition (x1) are prepared as a dilution solvent, and may be in the form of a solution. Examples of the coating method include spin coating, spray coating, bar coating, knife coating, roll coating, blade coating, die coating, and gravure coating.

However, drying or UV irradiation in the production method (I) and the production method (II) is preferably carried out by appropriately selecting the conditions under which the expandable particles are not swelled. For example, when drying the resin composition (y1) containing heat-expandable particles to form the base material (Y1), it is preferable that the drying temperature is less than the expansion start temperature (t) of the heat-expandable particles. In addition, in the case where the adhesive sheet (A) has an intumescent substrate (Y1-1) and a non-intumescent substrate (Y1'), in the aforementioned processes (Ia) and (IIa), the resin composition (y1) is For example, it may be pre-coated on the formed non-expandable substrate (Y1'). The non-expandable base material (Y') can be formed, for example, by the same operation as the above-mentioned steps (Ia) and (IIa) using the resin composition of the forming material of the non-expandable base material (Y').

[About the manufacturing method of the semiconductor device of the present embodiment] Next, each process concerning the manufacturing method of the semiconductor device of this embodiment is demonstrated. The manufacturing method of the semiconductor device according to the present embodiment has the following steps (1) to (3). Process (1): After attaching the workpiece to the adhesive layer (X1) of the adhesive sheet (A), cutting the workpiece to obtain a plurality of wafers on the adhesive layer (X1) . Process (2): Using an adhesive sheet (B) having a base material (Y2) and an adhesive layer (X2), on the surface opposite to the surface to which the adhesive layers (X1) of the plurality of chips are bonded Engineering of the adhesive layer (X2) of the sheet (B). Process (3): A process of expanding the expandable particles and separating the plurality of wafers and the adhesive sheet (A) attached to the adhesive sheet (B). Hereinafter, an example in which a semiconductor wafer is used as a workpiece will be described with reference to the drawings.

＜Project (1)＞ 2(a) and (b) are shown to illustrate that after attaching the semiconductor wafer W to the adhesive layer (X1) of the adhesive sheet (A), the semiconductor wafer W is diced to obtain individual pieces on the adhesive layer (X1). ) is a cross-sectional view of the process (1) of a plurality of semiconductor wafers CP.

The semiconductor wafer W may be, for example, a silicon wafer or a compound semiconductor wafer such as gallium and arsenic. The semiconductor wafer W has a circuit W2 on its circuit surface W1. As a method of forming the circuit W2, an etching method, a lift-off method, etc. are mentioned, for example. However, in this specification, the surface on the opposite side to the circuit surface W1 is called "wafer back surface". The semiconductor wafer W is ground to a predetermined thickness, the back surface of the wafer is exposed, and it is attached to the adhesive sheet (A). As a method of grinding the semiconductor wafer W, for example, a well-known method using a grinder or the like can be mentioned. For the purpose of holding the semiconductor wafer W for the adhesive sheet (A), a ring frame may be attached. In this case, the annular frame and the semiconductor wafer W are placed on the adhesive layer (X1) of the adhesive sheet (A), and they are lightly pressed and fixed. Next, the semiconductor wafer W held on the adhesive sheet (A) is separated into pieces by dicing to form a plurality of semiconductor wafers CP. For cutting, for example, cutting means using cutting machines, lasers, plasma cutting, stealth cutting, etc. are used. The cutting depth at the time of dicing may be appropriately set in consideration of the thickness of the semiconductor wafer, but for example, it can be used as a depth within 2 μm above the self-adhesive layer (X1). However, in order to distinguish this process from another cutting process described later, there is a case called "first cutting process". In the step (1), after dicing the semiconductor wafer W, in order to expand the distance between the obtained plurality of semiconductor wafers CP, a process including stretching the adhesive sheet (A) may be employed.

＜Project (2)＞ 3 is a diagram illustrating the use of an adhesive sheet (B) having a base material (Y2) and an adhesive layer (X2), on the surface opposite to the surface to which the adhesive layers (X1) of the plurality of semiconductor wafers CP are bonded, Cross-sectional view of the process (2) of the adhesive layer (X2) of the adhesive sheet (B).

The form of the adhesive sheet (B) may be appropriately determined according to subsequent processes. For example, in the case where an expansion process for expanding the spacing between a plurality of semiconductor wafers CP is performed as the next process of the first dicing process, as the adhesive sheet (B), an adhesive sheet for expansion (hereinafter, also referred to as " expansion tape”). On the other hand, in consideration of the workability of subsequent processes, between the first dicing process and the expansion process, an inversion process of inverting the front and back surfaces (ie, the circuit surface W1 and the wafer back surface) of a plurality of semiconductor wafers CP is performed. In the case of , it suffices to use an adhesive sheet for reversal (hereinafter, also referred to as "adhesive sheet for reversal"). FIG. 3 shows an example in which the adhesive sheet for reversal is used as the adhesive sheet (B). Next, the form of the optimal adhesive sheet (B) will be described as the adhesive sheet for reversal and the expansion tape.

(Adhesive sheet for reversal) The adhesive sheet for reversal has a base material (Y2) and an adhesive layer (X2), and after transferring a plurality of semiconductor wafers CP from the adhesive sheet (A), the plurality of semiconductor wafers CP are further transferred to another The adhesive sheet is used in order to invert the surface in contact with the adhesive layer of the semiconductor wafer CP. The adhesive sheet for reversal is not particularly limited as long as it can achieve the above purpose, but it must be able to be attached to and detached from the semiconductor wafer, such as an adhesive sheet containing expandable particles such as the adhesive sheet (A), and the expansion tape described later. , An adhesive sheet with an adhesive layer composed of a non-energy ray-curable adhesive with releasability, an adhesive sheet with an adhesive layer composed of a self-energy ray-curable adhesive, etc. are the best. The base material (Y2) of the pressure-sensitive adhesive sheet for reversal can be formed by using the structure mentioned as the forming material of the base material (Y1) of the pressure-sensitive adhesive sheet (A). In addition, the adhesive layer (X2) as the adhesive sheet for reversal can be formed using the constitutions mentioned as the forming material of the adhesive layer (X1) or the adhesive layer (X2) of the expansion tape described later. When the adhesive sheet (A) is used as the adhesive sheet (B), the form of the adhesive sheet (A) used in the process (1) and the form of the adhesive sheet (A) used in this process may be the same or different.

The thickness of the base material (Y2) of the adhesive sheet for reversal is desirably 10 to 1000 μm, more desirably 20 to 500 μm, still more desirably 25 to 400 μm, and still more desirably 30 to 300 μm. The thickness of the adhesive layer (X2) of the adhesive sheet for reversal is desirably 1 to 60 μm, more desirably 2 to 50 μm, still more desirably 3 to 40 μm, and still more desirably 5 to 30 μm.

(expansion tape) Next, the optimum adhesive sheet (B) will be described as the expansion tape. The expansion tape has a base material (Y2) and an adhesive layer (X2), and after transferring a plurality of semiconductor chips CP from the adhesive sheet (A) to the adhesive layer (X2), in order to space the plurality of semiconductor chips CP from each other , stretch the adhesive sheet (B) for expansion and use.

As the material system of the base material (Y2) of the expansion tape, for example, polyvinyl chloride resin, polyester resin (polyethylene terephthalate, etc.), acrylic resin, polycarbonate resin, polyethylene resin, poly Acrylic resin, acrylonitrile, butadiene, styrene resin, polyimide resin, polyurethane resin, and polystyrene resin, etc. The base material (Y2) of the expansion tape contains a thermoplastic elastomer, preferably a rubber-based material, and more preferably a thermoplastic elastomer. Examples of thermoplastic elastic systems include urethane-based elastomers, olefin-based elastomers, vinyl chloride-based elastomers, polyester-based elastomers, styrene-based elastomers, acrylic-based elastomers, and amide-based elastomers Wait.

The base material (Y2) of the expansion tape may be a film formed by laminating the above-mentioned materials in multiple layers, or a film formed by laminating the above-mentioned materials and other films may be used. The base material (Y2) of the expansion tape is a film with the above-mentioned resin-based material as the main material, and various additives such as pigments, dyes, flame retardants, plasticizers, antistatic agents, lubricants, fillers, etc. can also be included .

The adhesive layer (X2) of the expansion tape may be composed of a non-energy ray curable adhesive, or may be composed of an energy ray curable adhesive. The non-energy ray-curable adhesive is preferably a composition having desired adhesive force and releasability, for example, acrylic adhesives, rubber-based adhesives, polysiloxane-based adhesives, urethane-based adhesives Ester adhesives, polyester adhesives, polyvinyl ether adhesives, etc. Among these, an acrylic adhesive is preferable from the viewpoint of effectively suppressing the falling off of a semiconductor wafer or the like when the adhesive sheet (B) is stretched.

The energy ray-curable adhesive is cured by energy ray irradiation, and since the adhesive force is lowered, when the semiconductor wafer and the adhesive sheet (B) are separated, they can be easily separated by energy ray irradiation. Examples of the energy ray-curable adhesive system constituting the adhesive layer (X2) of the expansion tape include those selected from the group consisting of (a) a polymer having energy ray curability, and (b) at least one type of The constitution of one or more kinds of monomers and/or oligomers of the energy ray curable group. (a) A (meth)acrylate (co)polymer having an energy-ray-curable functional group (energy-ray-curable group) such as an unsaturated group introduced into a side chain as an energy-ray-curable polymer better. Examples of the acrylate (co)polymer system include alkyl (meth)acrylates having 1 to 18 carbon atoms in the alkyl group, double bonds with polymerizability, hydroxyl groups, carboxylic acids , an amino group, a substituted amino group, an epoxy group and other functional groups are formed by reacting an unsaturated group-containing compound having a functional group bonded to the functional group after copolymerization of the monomer in the molecule. (b) Examples of monomers and/or oligomers having at least one or more energy ray-curable groups include: esters of polyvalent alcohols and acrylic acid, and specific examples include: cyclohexyl (methyl) ) acrylates, isobornyl (meth)acrylates, monofunctional acrylates such as trimethylolpropane tri(meth)acrylates, pentaerythritol tri(meth)acrylates, pentaerythritol tetra(meth)acrylates ) acrylate, polydipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate Polyfunctional acrylates such as (meth)acrylates, tricyclodecane dimethanol di(meth)acrylates, polyester oligo(meth)acrylates, polyurethane oligo(meth)acrylates, etc. . In the energy ray-curable adhesive, a photopolymerization initiator, a crosslinking agent, and the like may be appropriately prepared in addition to the above-mentioned components.

The thickness of the base material (Y2) of the expansion tape is not particularly limited, but is preferably 20 to 250 μm, and more preferably 40 to 200 μm. The thickness of the adhesive layer (X2) of the expansion tape is not particularly limited, but is preferably 3 to 50 μm, and more preferably 5 to 40 μm.

At 23° C., the elongation at break of the expansion tape measured in the MD direction and the CD direction is preferably 100% or more, respectively. When the elongation at break is in the above-mentioned range, the elongation can be increased. Therefore, for the manufacture of the fan-out package, it is necessary to sufficiently separate the semiconductor chips from each other, and it can be used appropriately.

However, when the adhesive layer (X2) of the adhesive sheet (B) is composed of an energy ray-curable adhesive, it is preferable that the expandable particles of the adhesive sheet (A) are thermally expandable particles.

＜Project (3)＞ FIG. 4 is a cross-sectional view illustrating a process ( 3 ) of expanding the thermally expandable particles and separating a plurality of semiconductor wafers CP and an adhesive sheet (A). In this process, when the expandable particles are expanded by heat, energy rays, etc. according to their types, they form concavities and convexities on the adhesive surface (X1a) of the adhesive layer (X1), and through this, the adhesive surface (X1a) is formed. ) and the plurality of semiconductor chips CP decreased, and the adhesive sheet (A) was separated from the plurality of semiconductor chips CP.

The method of expanding the expandable particles may be appropriately selected according to the type of the expandable particles, and when the expandable particles are thermally expandable particles, heating may be performed to a temperature equal to or higher than the expansion start temperature (t). Here, as the “temperature above the expansion start temperature (t)”, it is preferable to be the “expansion start temperature (t) + 10°C” or higher and the “expansion start temperature (t) + 60°C” or lower, and the “expansion start temperature (t) + 60°C” is preferable. (t)+15°C" or more "expansion start temperature (t)+40°C" or less is more preferable. Specifically, according to the type of the expandable particles, for example, it may be heated in the range of 70 to 330° C. to expand.

The expansion of the expandable particles is preferably carried out in a state of being fixed to the surface (Y1a) on the opposite side to the adhesive layer (X1) of the base material (Y1). When passing through the fixing surface (Y1a), the generation of unevenness on the side of the surface (Y1a) is physically suppressed, and the unevenness can be efficiently formed on the adhesive surface (X1a) side of the adhesive layer (X1). Arbitrary methods can be adopted for the above-mentioned fixing system. For example, a method of disposing the above-mentioned non-expandable base material (Y1') on the surface (Y1a) side of the base material (Y1) is used as a fixing jig. A suction stage with a plurality of suction holes, a method of fixing the surface (Y1a) of the base material (Y1), and attaching a hard support to the surface (Y1a) of the base material (Y1) by an arbitrary adhesive layer, a double-sided adhesive sheet, etc. ) method, etc. The suction stage has a decompression mechanism such as a vacuum pump, and when the object is sucked from a plurality of suction holes through the decompression mechanism, the object is fixed to the suction surface. The material of the aforementioned rigid support can be appropriately determined in consideration of mechanical strength, heat resistance, etc., for example, metal materials such as SUS; non-metallic inorganic materials such as glass and silicon wafers; epoxy, Resin materials of ABS, acrylic, engineering plastics, super engineering plastics, polyimide, polyimide, etc.; composite materials such as glass epoxy resin, etc., among them, SUS, glass, and silicon wafers It is better to wait. As engineering plastics, nylon, polycarbonate (PC), polyethylene terephthalate (PET), etc. are mentioned. Examples of super engineering plastics include polyphenylene sulfide (PPS), polyether sulfide (PES), polydiether ketone (PEEK), and the like.

＜Expansion Project＞ Next, an expansion process of expanding the distance between the plurality of semiconductor wafers CP obtained above is performed. The expansion process is based on the form of the adhesive sheet (B). After the process (3), the following process (4A) or processes (4B-1) to (4B-3) (hereinafter, also referred to as "process (4B)" can be carried out. )") while proceeding.

Process (4A): The adhesive sheet (B) is an adhesive sheet for expansion, and the process of stretching and expanding the adhesive sheet for expansion is performed at a distance between the plurality of semiconductor chips attached to the adhesive sheet (B).

Process (4B-1): Attach the adhesive layer ( X3) works. Process (4B-2): The process of separating the adhesive sheet (B) from the plurality of semiconductor wafers CP attached to the adhesive sheet (C). Process (4B-3): The process of stretching and expanding the above-mentioned adhesive sheet for expansion between the plurality of semiconductor wafers attached to the adhesive sheet (C).

The process (4A) refers to the case where the adhesive sheet (B) used in the process (2) is the expansion tape. This situation is for example to stretch the adhesive sheet (B) to expand the distance between the plurality of semiconductor chips CP.

Process (4B) is the case where the adhesive sheet (B) is the adhesive sheet for reversal, the adhesive sheet (B) of the adhesive sheet for reversal, and the adhesive sheet (B) for transferring a plurality of semiconductor wafers CP to the adhesive sheet for expansion ( C) After that, carry out the expansion project. In the present embodiment, the process (4B) will be described.

5(a) and (b) are shown on the surface opposite to the surface in contact with the adhesive layer (X2) of the plurality of semiconductor wafers CP on the adhesive sheet (B) of the adhesive sheet for reversal, and paste the Cross-sectional view of the process (4B-1) of attaching the adhesive layer (X3) of the adhesive sheet (C) of the expansion tape, and then the process (4B-2) of separating the adhesive sheet (B) from the plurality of semiconductor wafers CP. The method of separating the adhesive sheets (B) from the plurality of semiconductor wafers CP may be appropriately selected according to the type of the adhesive sheets (B), and the adhesive layer (X2) of the adhesive sheets (B) is cured by non-energy rays In the case where the adhesive is made of an energy ray-curable adhesive, it can be peeled off again under specific conditions, and the adhesive layer (X2) is made of an energy ray-curable adhesive. After the force is reduced, the separation can be carried out. The ideal form of the expansion tape is as described above.

Fig. 6(a) and (b) show the process (4B-3) of stretching and expanding the adhesive sheet (C) at a distance from each other CP between the plurality of semiconductor wafers attached to the adhesive sheet (C) for the expansion tape. sectional view. After the above process, as shown in FIG. 6( a ), a plurality of semiconductor chips CP are placed on the adhesive layer (X3) of the adhesive sheet (C). Next, as shown in FIG.6(b), the adhesive sheet (C) is stretched, and the space|interval of a plurality of semiconductor wafers CP is extended to the distance D. Examples of the method of stretching the adhesive sheet (C) include: a method of stretching the adhesive sheet (C) by pushing against a ring-shaped or circular dilator, and grasping the outer peripheral portion of the adhesive sheet (C) using a gripping member or the like The method of stretching, etc. The distance D between the plurality of semiconductor wafers CP after expansion may be appropriately determined according to the form of the desired semiconductor device, but is preferably 50 to 6000 μm.

＜Project (5)~(8)＞ The manufacturing method of the semiconductor device concerning this embodiment uses the adhesive sheet (D) which has a base material (Y4) and an adhesive layer (X4), and may further implement the following processes (5)-(8). Process (5): A process of transferring the plurality of semiconductor wafers CP whose intervals are expanded by the expansion process to the adhesive layer (X4) of the adhesive sheet (D). Process (6): Coating the plurality of semiconductor wafers CP with a sealing material and the peripheral portions of the plurality of semiconductor wafers CP among the adhesive surfaces of the adhesive layer (X4), and curing the sealing material to obtain the above-mentioned semiconductor wafers The work of enclosing a hardened sealing body made of hardened sealing material. Process (7): The process of separating the adhesive sheet (D) from the aforementioned hardened sealing body. Process (8): The process of forming a redistribution layer by separating the hardened closed body of the adhesive sheet (D). However, as the adhesive sheet (D), the adhesive sheet (C) of the expansion tape can also be used, and in this case, the process (5) is not required. In this case, the pressure-sensitive adhesive sheet (D) described below refers to the structure of the pressure-sensitive adhesive sheet (C). Hereinafter, the steps (5) to (8) will be described in order.

[Process (5)] Process (5): A process of transferring the plurality of semiconductor wafers CP whose intervals are expanded by the expansion process to the adhesive layer (X4) of the adhesive sheet (D). 7 (a) and (b) are shown on the surface opposite to the surface in contact with the adhesive layer (X3) of the plurality of semiconductor wafers CP on the expansion adhesive sheet (C), the adhesive sheet (D) is attached to the surface opposite to the surface. A cross-sectional view of the process of separating the adhesive sheet (C) from the plurality of semiconductor wafers CP after the adhesive layer (X4). Here, the adhesive sheet (D) has a structure in which a plurality of semiconductor wafers CP are sealed on the adhesive surface (X4a) to obtain a hardened seal, and then separated from the hardened seal. Then, for the adhesive sheet (D) between the sealing through the sealing body, there is no positional shift of the semiconductor chip, and it is required that the sealing material does not enter the interface between the semiconductor chip and the temporary fixing sheet. Adhesion, and requires separation that can be easily removed after closure. The adhesive sheet (D) is not particularly limited if it can achieve the above purpose, but it must be able to be attached to and detached from the semiconductor wafer. An adhesive sheet having an adhesive layer composed of a releasable non-energy ray-curable adhesive, an adhesive sheet having an adhesive layer composed of a self-energy ray-curable adhesive, and the like are preferred. Among these, it is preferable to use the adhesive sheet (A) from the viewpoint of coexistence of excellent adhesiveness and separability. When the adhesive sheet (A) is used as the adhesive sheet (D), the form of the adhesive sheet (A) used in the process (1) and the form of the adhesive sheet (A) used in this process may be the same or different.

In this process, the method of separating the adhesive sheet (C) and the plurality of semiconductor wafers CP is the same as the case of the adhesive sheet (B), and may be determined according to the form of the adhesive sheet (C).

[Process (6)] 8( a ) to ( c ) show and explain that a plurality of semiconductor wafers CP are covered with the sealing material 40 , and among the adhesive surfaces ( X4 a ) of the adhesive layer ( X4 ), the peripheral portions 45 of the plurality of semiconductor wafers CP (Hereinafter, this process is also referred to as a "coating process"), the sealing material 40 is hardened (hereinafter, this process is also referred to as a "hardening process"), and a plurality of semiconductor wafers CP are obtained to be sealed in the hardening sealing material 41 A cross-sectional view of the process (6) of the hardened enclosure 50 formed.

The sealing material 40 has a function of protecting a plurality of semiconductor wafers CP from the outside and the elements attached thereto. The sealing material 40 is not particularly limited, and any configuration can be appropriately selected and used from among the configurations used as a semiconductor sealing material in the past. The sealing material 40 has a curable structure from the viewpoints of mechanical strength, heat resistance, insulating properties, and the like, and examples thereof include a thermosetting resin composition, an energy ray curable resin composition, and the like. Examples of the thermosetting resin system of the thermosetting resin composition containing the sealing material 40 include epoxy resins, phenol resins, cyanate resins, etc. From the viewpoint of properties and the like, epoxy resin is preferable. The above-mentioned thermosetting resin composition is other than the above-mentioned thermosetting resin, as necessary, containing a phenol resin-based hardener, an ammonia-based hardener and other hardeners, a hardening accelerator, an inorganic filler such as silica, elastic Additives such as body can also be used. The sealing material 40 may be solid or liquid at room temperature. In addition, the form of the sealing material 40 which is a solid shape at room temperature is not particularly limited, and for example, a granular form, a flake form, or the like may be used. In this embodiment, the covering process and the hardening process are performed using a sheet-shaped sealing material (hereinafter, also referred to as a "sheet-shaped sealing material"). In the method of using the sheet-like sealing material, the sheet-like sealing material is placed so as to cover the plurality of semiconductor wafers CP and the peripheral portions 45 thereof, and the plurality of semiconductor wafers CP and the peripheral portions thereof are covered through the sealing material 40 . 45. At this time, it is preferable to decompress, heat and press the portion where the unfilled sealing material 40 is not generated in the gaps between the plurality of semiconductor wafers CP by a vacuum lamination method or the like.

As a method of covering a plurality of semiconductor wafers CP and their peripheral portions 45 through the sealing material 40, any method can be appropriately selected and applied among the conventional semiconductor sealing process methods. For example, a roll lamination method can be applied. , vacuum stamping method, vacuum lamination method, spin coating method, die coating method, transfer molding method, compression molding casting method, etc. In these methods, generally, in order to improve the filling property of the sealing material 40, the sealing material 40 is heated during coating to impart fluidity. In the above-mentioned coating process, the temperature of heating the thermosetting resin composition varies depending on the type of the sealing material 40, the type of the adhesive sheet (D), etc., but for example, 30 to 180°C and 50 to 170°C are Better, 70~150℃ better. In addition, the heating time is, for example, 5 seconds to 60 minutes, preferably 10 seconds to 45 minutes, and more preferably 15 seconds to 30 minutes.

As shown in FIG. 8( b ), the sealing material 40 covers the entire surface of the plurality of semiconductor wafers CP, and also fills the gaps between the plurality of semiconductor wafers CP.

Next, as shown in FIG. 8( c ), after the coating process is performed, the sealing material 40 is hardened to obtain a hardened sealing body 50 in which a plurality of semiconductor wafers CP are sealed in the hardened sealing material 41 . In the above-mentioned hardening process, the temperature for curing the sealing material 40 varies depending on the type of the sealing material 40, the type of the adhesive sheet (D), etc., but for example, 80-240°C, preferably 90-200°C, 100~170℃ is better. In addition, the heating time is, for example, 10 to 180 minutes, preferably 20 to 150 minutes, and more preferably 30 to 120 minutes. Through the process (6), the hardening sealing body 50 in which the plurality of semiconductor chips CP separated by the specific distances are embedded in the hardening sealing material 41 can be obtained.

[Process (7)] Next, as shown in FIG. 8( d ), the adhesive sheet (D) is separated from the hardening sealing body 50 . The method of separating the adhesive sheet (D) may be appropriately selected according to the type of the adhesive sheet (D). When the adhesive sheet (A) is used as the adhesive sheet (D), it is one that can be separated from the hardened sealing body 50 by expanding the expandable particles contained in the adhesive sheet (A). The conditions for expanding the expandable particles are as described in the adhesive sheet (A).

However, in the present embodiment, an example in which the sealing process is performed on the circuit surface W1 of a plurality of semiconductor chips CP in a state of being in contact with the adhesive layer (X4) of the adhesive sheet (D) has been described. In the state of exiting (ie, the state in which the backside of the wafer is in contact with the adhesive layer (X4)), the sealing process can also be performed. In this case, the circuit surfaces W1 of the plurality of semiconductor wafers CP are covered with the sealing resin, but after curing the sealing resin, if appropriate, a grinding machine or the like is used to cut and harden the sealing material, and the circuit surfaces W1 may be expressed again. .

[Process (8)] 9( a ) to ( c ) are cross-sectional views illustrating a process ( 8 ) of forming a redistribution layer by separating the hardened sealing body 50 of the adhesive sheet (D). FIG. 9( b ) is a cross-sectional view illustrating the process of forming the first insulating layer 61 on the circuit surface W1 of the semiconductor wafer CP and the surface 50a of the hardened sealing body 50 . The first insulating layer 61 made of insulating resin is formed on the circuit surface W1 and the surface 50a so as to expose the circuit W2 of the semiconductor wafer CP or the internal terminal electrodes W3 of the circuit W2. As a heat-resistant resin system, a polyimide resin, a polybenzoxazole resin, a polysiloxane resin, etc. are mentioned. The material of the internal terminal electrode W3 is not limited as long as it is a conductive material, and examples thereof include metals such as gold, silver, copper, and aluminum, and alloys containing these metals.

FIG. 9( c ) is a cross-sectional view illustrating a process of forming a redistribution line 70 electrically connected to the semiconductor chip CP enclosed by the hardened sealing body 50 . In the present embodiment, the rewiring 70 is formed following the formation of the first insulating layer 61 . The material of the rewiring 70 is not limited as long as it is a conductive material, and examples thereof include metals such as gold, silver, copper, and aluminum, and alloys containing these metals. The rewiring 70 can be formed by a known method such as an erasing method and a semi-additive method.

FIG. 10( a ) is a cross-sectional view illustrating a process of forming the second insulating layer 62 covering the redistribution wiring 70 . The rewiring 70 has external electrode pads 70A for external terminal electrodes. Openings or the like are provided in the second insulating layer 62 to expose the external electrode pads 70A for external terminal electrodes. In the present embodiment, the external electrode pads 70A are within the range of the semiconductor wafer CP of the hardened enclosure 50 (corresponding to the range of the circuit surface W1 ) and outside the range (corresponding to the range of the surface 50a on the hardened enclosure 50 ). and exposed. In addition, the rewiring 70 is formed on the surface 50a of the hardened sealing body 50 so as to arrange the external electrode pads 70A in an array. In the present embodiment, FOWLP or FOPLP can be obtained because of the structure in which the external electrode pads 70A are exposed outside the range of the semiconductor wafer CP of the hardened enclosure 50 .

(Connection process to external terminal electrodes) Next, if necessary, the external terminal electrode 80 may be connected to the external electrode pad 70A. FIG. 10( b ) is a cross-sectional view illustrating a process of connecting the external terminal electrode 80 to the external electrode pad 70A. External terminal electrodes 80 such as solder balls are placed on the external electrode pads 70A exposed from the second insulating layer 62 , and the external terminal electrodes 80 and the external electrode pads 70A are electrically connected by solder bonding or the like. The material of the solder ball is not particularly limited, but lead-containing solder, lead-free solder, and the like are exemplified.

(Second cutting process) FIG. 10( c ) is a cross-sectional view illustrating a second dicing process for dividing the hardened sealing body 50 to which the external terminal electrodes 80 are connected into pieces. In this process, the encapsulation body 50 is individually hardened into pieces in units of semiconductor wafers CP. The method of individualizing the hardened sealing body 50 is not particularly limited, and it can be implemented by cutting means such as a cutter. The semiconductor device 100 of the semiconductor wafer CP unit is manufactured by making the cured sealing body 50 into individual pieces. As described above, the semiconductor device 100 to which the external terminal electrodes 80 are connected to the external electrode pads 70A outside the range of the semiconductor wafer CP is manufactured as FOWLP, FOPLP, or the like.

(Installation work) In the present embodiment, it is also preferable to include the process of mounting the individualized semiconductor device 100 on a printed wiring board or the like. [Example]

The present invention is specifically described through the following examples, but the present invention is not limited to the following examples. However, the physical property values in the following production examples and examples are values measured by the following methods.

<Mass average molecular weight (Mw)> The measurement was performed under the following conditions using a colloid permeation chromatography apparatus (manufactured by TOSOH Co., Ltd., product name "HLC-8020"), and the value measured in terms of standard polystyrene was used. (measurement conditions) ・Column: "TSK guard column HXL-L", "TSK gel G2500HXL", "TSK gel G2000HXL" and "TSK gel G1000HXL" (all manufactured by TOSOH Co., Ltd.) are connected in sequence. Column temperature: 40℃ ・Development solvent: Tetrahydrofuran ・Flow rate: 1.0mL/min

<Measurement of thickness of each layer> The measurement was performed using a constant pressure thickness measuring device (model: "PG-02J", standard specification: based on JIS K6783, Z1702, Z1709) manufactured by TECLOCK Co., Ltd.

<Average particle diameter (D ₅₀ ), 90% particle diameter (D ₉₀ ) of thermally expandable particles> Using a laser diffraction particle size distribution analyzer (for example, manufactured by Malvern Corporation, product name "MASTERSIZER 3000"), measured at 23 Particle distribution of heat-expandable particles before expansion at °C. In addition, the cumulative volume frequency calculated from the smaller particle size of the particle distribution is equivalent to 50% and 90% of the particle size, and the "average particle size of thermally expandable particles (D ₅₀ )" and "90% of thermally expandable particles" % particle diameter (D ₉₀ ).

<Storage elastic modulus E' of intumescent base material> When the measurement object is a non-adhesive intumescent base material, the expansive base material is set as a size of 5 mm in length x 30 mm in width x 200 μm in thickness, and a test sample is prepared by removing the release material. Using a dynamic viscoelasticity measuring device (manufactured by TA Instruments, product name "DMAQ800"), under the conditions of a test start temperature of 0°C, a test end temperature of 300°C, a temperature rise rate of 3°C/min, a vibration frequency of 1 Hz, and an amplitude of 20 μm, the specific At the temperature of , the storage elastic modulus E' of the test sample was measured.

<Shear storage modulus G’ of adhesive layer> In the case where the measurement object is an adhesive layer with adhesiveness, the adhesive layer is 8 mm in diameter x 3 mm in thickness, and the release material is removed to prepare a test sample. Using a viscoelasticity measuring device (manufactured by Anton Paar, device name "MCR300"), under the conditions of a test start temperature of 0°C, a test end temperature of 300°C, a heating rate of 3°C/min, and a vibration frequency of 1 Hz, through the torsional shear method, At a specific temperature, the shear storage modulus G' of the test sample is determined. In addition, the value of the storage elastic modulus E' is calculated from the approximate formula "E'=3G'" based on the value of the measured shear force storage modulus G'.

<Probe Adhesion Value> After cutting the intumescent substrate or adhesive layer to be measured into a square of 10 mm on one side, let it stand for 24 hours in an environment of 23°C and 50% RH (relative humidity), and then remove the The composition of the lightly peeled film was used as a test sample. The aforementioned test sample was subjected to a seam testing machine (manufactured by Nippon Special Instruments Co., Ltd., product name "NTS-4800") in an environment of 23°C and 50% RH (relative humidity), and the light peeling film was removed to show the performance. Then, according to JIS Z0237:1991, the probe adhesion value on the surface of the aforementioned test sample was measured. Specifically, a stainless steel probe with a diameter of 5 mm was brought into contact with the surface of the test sample at a contact load of 0.98 N/cm ² for 1 second, and then the probe was measured at a speed of 10 mm/sec. The force necessary to remove the surface. Then, the measured value was used as the probe sticking value of this test sample.

The details of the adhesive resin, additives, heat-expandable particles, and release material used in the formation of each layer in the following production examples are as follows. <Adhesive resin> ・Acrylic copolymer (i): has a raw material list derived from 2-ethylhexyl acrylate (2EHA)/2-hydroxyethyl acrylate (HEA)=80.0/20.0 (mass ratio) The structural unit of the body contains a solution of an acrylic copolymer of Mw 600,000. Dilution solvent: ethyl acetate, solid content concentration: 40% by mass. <Additive> ・Isocyanate crosslinking agent (i): Tosoh Co., Ltd. make, product name "Coronate L", solid content concentration: 75 mass %.・Photopolymerization initiator (i): BASF Corporation, product name "IRGACURE184", 1-hydroxycyclohexyl-phenyl-methanone. <Heat-expandable particles> ・Heat-expandable particles (i): manufactured by Kureha Co., Ltd., product name "S2640", expansion start temperature (t) = 208°C, average particle size (D ₅₀ ) = 24 μm, 90% particle size ( D ₉₀ )=49 μm. <Release material> ・Heavy release film: manufactured by LINTEC Co., Ltd., product name "SP-PET382150", which is formed from a polysiloxane-based release agent on one side of a polyethylene terephthalate (PET) film. Composition of the release agent layer, thickness: 38 μm.・Light release film: manufactured by LINTEC Co., Ltd., product name "SP-PET381031", a structure in which a release agent layer formed from a polysiloxane-based release agent is provided on one side of the PET film, thickness: 38 μm.

Production Example 1 (Formation of Adhesive Layer (X1)) In the adhesive resin, the solid content of the solution of the acrylic copolymer (i) was 100 parts by mass, and 5.0 parts by mass of the isocyanate crosslinking agent (i) was prepared (solid content). ratio), further diluted with toluene, and uniformly stirred to prepare an adhesive composition (x1) having a solid content concentration (active ingredient concentration) of 25% by mass. And, on the surface of the release agent layer of the heavy peeling film, apply the prepared adhesive layer (x1) to form a coating film, and then dry the coating film at 100° C. for 60 seconds to form an adhesive with a thickness of 10 μm Layer (X1). However, at 23°C, the shear storage modulus G'(23) of the adhesive layer (X1) was 2.5×10 ⁵ Pa.

Production Example 2 (Formation of Intumescent Base Material (Y1-1)) In the terminal isocyanate urethane prepolymer obtained by reacting ester diol and isophorone diisocyanate (IPDI), 2- Hydroxyethyl acrylate was reacted to obtain a bifunctional urethane acrylate oligomer with a mass average molecular weight (Mw) of 5,000. In addition, 40 mass % (solid content ratio) of isobornyl acrylate (IBXA) was prepared as an energy ray polymerizable monomer in 40 mass % (solid content ratio) of the urethane acrylate oligomer synthesized above. ), and 20% by mass of phenylhydroxypropyl acrylate (HPPA) (solid content ratio), and for 100 parts by mass of the total amount of acrylic urethane oligomer and energy ray polymerizable monomer, more 2.0 mass parts (solid content ratio) of a photopolymerization initiator (i), and 0.2 mass part (solid content ratio) of a phthalocyanine type pigment as an additive were prepared, and the energy ray curable composition was prepared. In this energy-beam curable composition, the said thermally expandable particle (i) is mix|blended, and the solventless resin composition (y1) which does not contain a solvent is prepared. However, with respect to the total amount (100 mass %) of the resin composition (y1), the content of the thermally expandable particles (i) is 20 mass %. Next, on the surface of the release agent layer of the said light release film, the prepared resin composition (y1) was apply|coated, and the coating film was formed. Furthermore, using an ultraviolet irradiation device (manufactured by iGrafx, product name "ECS-401GX") and a high-pressure mercury lamp (manufactured by iGrafx, product name "H04-L41"), under the conditions of illuminance of 160 mW/cm ² and light intensity of 500 mJ/cm ² Then, ultraviolet rays were irradiated to harden the coating film to form an intumescent base material (Y1-1) with a thickness of 50 μm. However, the above-mentioned illuminance and light quantity at the time of ultraviolet irradiation are values measured using an illuminance and light quantity meter (manufactured by EIT Corporation, product name "UV Power Puck II"). However, the storage elastic modulus E' at 23°C of the intumescent substrate (Y1-1) obtained above was 5.0×10 ⁸ Pa, and the storage elastic modulus E′ at 100°C was 4.0×10 ⁶ Pa, The storage elastic modulus E' at 208°C is 4.0×10 ⁶ Pa. In addition, the probe adhesion value of the swellable substrate (Y1-1) is 2mN/5mmf.

Manufacturing Example 3 (Production of the adhesive sheet (A)) The adhesive layer (X1) formed in Production Example 1 and the surfaces of the intumescent base material (Y1-1) formed in Production Example 2 were bonded to each other. Through this, an adhesive sheet (A) in which the light release film/expandable substrate (Y1-1)/adhesive layer (X1)/heavy release film are laminated in this order is produced.

Manufacturing Example 4 (Production of Adhesive Sheet (B) (Expansion Tape)) Acrylic copolymer obtained by reacting butyl acrylate/2-hydroxyethyl acrylate=85/15 (mass ratio), and 80 mol% of isomethacrylate for its 2-hydroxyethyl acrylate The cyanoethyl ester (MOI) was reacted to obtain an energy ray hardening type polymer. The mass-average molecular weight (Mw) of this energy ray-curable polymer was 600,000. 100 parts by mass of the obtained energy ray-curable polymer, 3 parts by mass of 1-hydroxycyclophenyl ketone (manufactured by BASF, product name "IRGACURE 184") as a photopolymerization initiator, and 3 parts by mass as a cross-linking agent were mixed in a solvent. 0.45 mass part of the toluene diisocyanate type crosslinking agent (TOSOH company make, product name "Coronate L") of a linking agent, and the adhesive composition was obtained. Next, a release film (manufactured by LINTEC Co., Ltd., product name "SP-PET3811") formed by forming a polysiloxane-based release agent layer on one side of a polyethylene terephthalate (PET) film was peeled off. On the surface of the adhesive layer, the adhesive layer (X2) with a thickness of 10 μm was formed on the release film by applying the above-mentioned adhesive composition and drying it by heating. Then, on the exposed surface of the adhesive layer, as a base material (Y2), one side of a polyester-based polyurethane elastic sheet (manufactured by Sheedom, product name "HigressDUS202", thickness 50 μm) is attached to one side. The film is in the state of the adhesive layer to obtain an adhesive sheet (B) (expansion tape).

[Manufacture of semiconductor devices] Example 1 Using the adhesive sheet (A) and the adhesive sheet (B) obtained above, a semiconductor device was produced by the following method. ＜Project (1)＞ The adhesive sheet (A) obtained in Production Example 3 was cut into a size of 230 mm×230 mm. The heavy release film and the light release film are peeled off from the cut adhesive sheet (A), and a ring frame and a semiconductor wafer (diameter: 150 mm, thickness: 350 μm) are attached to the surface of the adhesive layer (X1) shown. Next, using a dicing machine (manufactured by Disco, product name "DFD-651"), the semiconductor wafer was completely cut and diced under the following conditions. Through this, on the adhesive layer (X1) of the adhesive sheet (A), a plurality of semiconductor wafers (1800 pieces) were obtained into individual pieces. ・Cutter: manufactured by Disco, product name "NBC-ZH2050 27HECC" ・Number of revolutions: 30,000rpm ・Height: 0.06mm ・60mm/sec ・Wafer size: 3mm×3mm ＜Project (2)＞ The adhesive sheet (B) obtained in Production Example 4 was cut into a size of 210 mm×210 mm. At this time, each side of the cut sheet is cut so as to be parallel or perpendicular to the MD direction of the base material (Y2) of the adhesive sheet (B). Next, from the adhesive sheet (B), the release sheet is peeled off, and the adhesive layer (X2) of the adhesive sheet (B) is attached to the surface opposite to the surface in contact with the adhesive layers (X1) of the plurality of semiconductor wafers. ). At this time, a group of semiconductor wafers are transferred so as to be positioned at the center of the adhesive sheet (B). In addition, the dicing lines when individualizing the semiconductor wafers are transferred in parallel or perpendicular to each side of the adhesive sheet (B). ＜Project (3)＞ Next, as the surface on the opposite side of the adhesive layer (X) of the intumescent base material (Y1-1) provided in the adhesive sheet (A), the hot plate is pressed to become the expansion start temperature of the thermally expansible particles (208°C) or higher, the adhesive sheet (A) is heated for 3 minutes at 240° C. to expand the thermally expandable particles, and the above-mentioned plural semiconductor wafers and the adhesive sheet (A) attached to the adhesive sheet (B) are separated. However, when the adhesive sheet (A) is separated, the adhesive sheet (A) is kept in a flat shape without being bent, and is simultaneously separated from a plurality of semiconductor wafers. ＜Expansion Project＞ Next, the adhesive sheet (B) to which the plurality of semiconductor wafers are attached is placed on an expansion device capable of biaxial extension. As shown in FIG. 11 , the expansion device has an X-axis direction (the positive direction is the +X-axis direction, and the negative direction is the -X-axis direction) and the Y-axis direction (the positive direction is +Y) that are orthogonal to each other. axis direction, the negative direction is referred to as -Y axis direction), and has holding means for extending in each direction (ie, +X axis direction, -X axis direction, +Y axis direction, -Y axis direction). The MD direction of the adhesive sheet (B) is matched with the X-axis or Y-axis direction, and is set in the expansion device. After holding each side of the adhesive sheet (B) through the aforementioned holding means, the following conditions are used to stretch the adhesive. In the sheet (B), the distance between the plurality of semiconductor chips attached to the adhesive layer (X2) of the adhesive sheet (B) is enlarged. ・Number of holding means: Near one side, 5 ・Extension speed: 5mm/sec ・Extend distance: Extend each side by 60mm.

Comparative Example 1 <Process (1)> In the case of a dicing tape (manufactured by Lintec Co., Ltd., trade name "D-820") having a base material and an adhesive layer (hereinafter, also referred to as "dicing tape for comparison") On the surface of the adhesive layer, a ring frame and a semiconductor wafer (diameter: 150 mm, thickness: 350 μm) are attached. After that, in the same manner as the process (1) of Example 1, a plurality of semiconductor wafers were obtained into individual pieces. <Process (2)> The same procedure as in Example 1 was performed. <Process (3)> The surface of the dicing tape for comparison was irradiated with ultraviolet rays with an illuminance of 230 mW/cm ² and a light intensity of 190 mJ/cm ² to harden the adhesive layer, and the above-mentioned plural numbers attached to the adhesive sheet (B) were separated. of semiconductor wafers with dicing tape for comparison. However, when the dicing tape for comparison was separated, the dicing tape for comparison was not bent and kept in a flat shape, and was simultaneously separated from a plurality of semiconductor wafers. <Expansion process> The same operation as Example 1 was performed.

[Evaluation of the presence or absence of wafer defects] The appearance of a plurality of semiconductor wafers after the expansion obtained above was observed with a microscope, the presence or absence of wafer defects in the semiconductor wafers was confirmed, and the evaluation was performed according to the following criteria. ・A: A structure with wafer defects. ・F: A structure with no wafer defect.

[Measurement of Adhesive Strength of Adhesive Sheets] (Measurement of adhesive force before and after heating of the adhesive sheet (A)) The light and thin release film of the produced adhesive sheet (A) is removed. Then, the heavy peeling film of the adhesive sheet (A) was also removed, and the adhesive surface of the adhesive layer (X1) exhibited was attached to the stainless steel plate (SUS304 No. 360 grinding) of the object to be attached, and the adhesive surface was attached at 23°C, The composition of standing for 24 hours in the environment of 50%RH (relative humidity) was used as the test sample. Using the above-mentioned test samples, under the environment of 23°C, 50% RH (relative humidity), according to JIS Z0237:2000, through the 180° peeling method, the adhesive force at 23°C was measured at a tensile speed of 300 mm/min. In addition, the above-mentioned test sample was heated on a hot plate at 240°C, which is not less than the thermally expansible particle expansion start temperature (208°C), for 3 minutes, and then heated in a standard environment (23°C, 50% RH (relative humidity) ) After standing for 60 minutes, the adhesive force after heating above the expansion start temperature was also measured under the same conditions as above.

(Measurement of the adhesive force of the dicing tape for comparison before and after irradiation with ultraviolet rays) The adhesive surface of the dicing tape for comparison (manufactured by LINTEC Co., Ltd., trade name "D-820") was attached to the stainless steel plate (SUS304 360) of the object to be attached. No. grinding), will stand at 23 ℃, 50% RH (relative humidity) environment for 24 hours, as a test sample, under the same conditions as the adhesive sheet (A), measure the 23 before ultraviolet irradiation ℃ adhesion. Next, after irradiating ultraviolet rays with an illuminance of 230 mW/cm ² and a light intensity of 190 mJ/cm ² from the base material side of the dicing tape for comparison, the adhesive force at 23° C. after ultraviolet irradiation was measured under the same conditions as above.

From the results in Table 1, the adhesive sheet (A) used in the manufacturing method of the present embodiment has a smaller adhesive force after expansion than that of the conventional UV-irradiated adhesive sheet, and can be obtained by dicing a semiconductor wafer through this. The plurality of wafers can be easily transferred to another adhesive sheet, and it has been found that the occurrence of wafer defects during transfer can be effectively suppressed.

1a‧‧‧Adhesive sheet (a) 1b‧‧‧Adhesive Sheet (a) 40‧‧‧Closing material 41‧‧‧hardened sealer 45‧‧‧Peripheral part of semiconductor chip CP 50‧‧‧hardened closure 50a‧‧‧face 61‧‧‧First insulating layer 62‧‧‧Second insulating layer 70‧‧‧Rewiring 70A‧‧‧External electrode gasket 80‧‧‧External terminal electrode 100‧‧‧Semiconductor device 200‧‧‧Expansion device 210‧‧‧Maintaining Means CP‧‧‧Semiconductor Chip W1‧‧‧circuit surface W2‧‧‧circuit W3‧‧‧Internal terminal electrode

FIG. 1 is a cross-sectional view showing an example of the configuration of the adhesive sheet (A) used in the manufacturing method according to the present embodiment, (a) the adhesive sheet a1 and (b) the adhesive sheet b1. FIG. 2 is a cross-sectional view illustrating an example of the manufacturing method according to the present embodiment. FIG. 3 is a sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 2 . FIG. 4 is a cross-sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 3 . FIG. 5 is a cross-sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 4 . FIG. 6 is a cross-sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 5 . FIG. 7 is a cross-sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 6 . FIG. 8 is a cross-sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 7 . FIG. 9 is a sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 8 . FIG. 10 is a cross-sectional view illustrating an example of the manufacturing method according to the present embodiment following FIG. 9 . FIG. 11 is a plan view illustrating the 2-axis extension dilation device used in the embodiment.

1a‧‧‧Adhesive sheet (a)

1b‧‧‧Adhesive Sheet (a)

X1‧‧‧Adhesive layer

Y1’‧‧‧Non-expandable substrate

Y1-1‧‧‧Substrate

Claims (10)

A method of manufacturing a semiconductor device using a method for manufacturing a semiconductor device having a substrate (Y1) and an adhesive layer (X1), in which any layer contains expandable particles, and an expandable adhesive sheet (A), wherein It is a manufacturing method of a semiconductor device having the following sequence of steps (1) to (3) in sequence; step (1): after attaching the object to be processed to the adhesive layer (X1) of the adhesive sheet (A), cutting the The process of obtaining a plurality of wafers on the adhesive layer (X1), process (2): using the adhesive sheet (B) with the base material (Y2) and the adhesive layer (X2), located in The process of attaching the adhesive layer (X2) of the adhesive sheet (B) to the surface opposite to the surface to which the adhesive layers (X1) of the plurality of wafers are bonded, and the process (3): expanding the expandable particles, The process of separating the plurality of wafers attached to the adhesive sheet (B) and the adhesive sheet (A); the substrate (Y1) of the adhesive sheet (A) is an intumescent substrate (Y1- 1); The storage elastic modulus E'(23) of the base material (Y1) at 23°C is 1.0×10 ⁶ ~5.0×10 ¹² Pa. The method for manufacturing a semiconductor device as described in item 1 of the scope of the application, wherein the adhesive sheet (B) is an adhesive sheet for expansion, and after the step (3), the following step (4A) is further included; Process (4A): The process of expanding the space between the plurality of chips attached to the adhesive sheet (B) by stretching the adhesive sheet (B). The method for manufacturing a semiconductor device according to the claim 1, wherein the following process (4B-1) is further carried out using an adhesive sheet (C) for expansion having a substrate (Y3) and an adhesive layer (X3) )~(4B-3), Process (4B-1): On the surface opposite to the surface where the adhesive layers (X2) of the plurality of chips on the adhesive sheet (B) are bonded, stick the adhesive sheet (C) The process of the adhesive layer (X3), the process (4B-2): the process of separating the adhesive sheet (B) from the plural wafers attached to the adhesive sheet (C), the process (4B-3): by stretching The sticking sheet (C) is a process of expanding the space between the plurality of chips attached to the sticking sheet (C). The method for manufacturing a semiconductor device according to the claim 2 or 3 of the claimed scope, wherein the above-mentioned adhesive sheet for expansion is measured at 23° C. in the MD direction and the CD direction, and the elongation at break is 100% or more . The method for manufacturing a semiconductor device according to any one of the claims 1 to 3 of the claimed scope, wherein the expandable particles are thermally expandable particles having an expansion start temperature (t) of 60 to 270°C, and the process ( 3) The process of separating the plurality of chips attached to the adhesive sheet (B) and the adhesive sheet (A) by heating the adhesive sheet (A). The method for manufacturing a semiconductor device according to any one of claims 1 to 3 of the claimed scope, wherein the step (1) includes a process of stretching the adhesive sheet (A) after cutting the workpiece. The method for manufacturing a semiconductor device according to any one of claims 1 to 3 of the claimed scope, wherein the adhesive layer (X1) of the adhesive sheet (A) is measured at 23° C. before the expansion of the expandable particles. The adhesion is 0.1~10.0N/25mm. The manufacturing method of a semiconductor device according to any one of claims 1 to 3 of the claimed scope, wherein the probe adhesion value on the surface of the substrate (Y1) of the adhesive sheet (A) is less than 50 mN/5mmΦ. The method for manufacturing a semiconductor device according to any one of claims 1 to 3 of the claimed scope, wherein the workpiece is a semiconductor wafer. The method for manufacturing a semiconductor device according to item 9 of the scope of the application is a method for manufacturing a fan-out type semiconductor device.

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