JP2005255909A - Adhesive sheet, manufacturing method of semiconductor device using the same, and semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an adhesive sheet which can sufficiently reduce the development of the peeling prior to the use between a removable base material and a laminated body and which, in the step of stripping the laminated body from the removable base material and attaching it to a semiconductor wafer, can sufficiently reduce the development of defective stripping. <P>SOLUTION: The adhesive sheet has a structure of which the removable base material 12, the adhesive layer 14, the tacky layer 22, and the substrate film 24 are successively laminated. The adhesive layer 14 is partially formed on the removable base material 12, the tacky layer 22 covers the adhesive layer 14 and is formed so that its peripheral part comes into contact with the removable base material 12, the removable base material 12 is 3-100 μm thick and has a tensile modulus at 25°C of ≥1,000 MPa, the substrate film 24 is 20-300 μm thick and has a tensile modulus at 25°C of 10-300 MPa, and the 90° peel strength at 25°C between the removable base material 12 and the tacky layer 22 is 0.1-20 N/m. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention mainly relates to an adhesive sheet for bonding a semiconductor element to a support member, a method of manufacturing a semiconductor device using the same, and a semiconductor device.

  Conventionally, a silver paste has been mainly used for joining a semiconductor element and a support member for mounting the semiconductor element. However, with the recent miniaturization and high performance of semiconductor elements, the support members used are required to be small and fine. In response to these requirements, silver paste meets the above requirements due to occurrence of defects during wire bonding due to protrusion or inclination of semiconductor elements, difficulty in controlling the thickness of the adhesive layer, and generation of voids in the adhesive layer. It has become impossible to deal with.

  Therefore, in order to cope with the above requirements, in recent years, a film-like adhesive (hereinafter referred to as “adhesive film”) has been used. This adhesive film usually has a configuration in which an adhesive layer is formed on a release substrate, and is used when a semiconductor device is manufactured by a piece attaching method or a wafer back surface attaching method.

  When a semiconductor device is manufactured by the former piece pasting method, it can be manufactured, for example, by the following procedure. First, an adhesive film wound in a reel shape is drawn out to a required length, cut out into individual pieces by cutting or punching, and then the individual pieces are bonded to a support member for mounting a semiconductor element. Next, the semiconductor element separated through the dicing process is joined to the support member with the adhesive layer after the release substrate is peeled from the adhesive film via the adhesive layer to produce the support member with the semiconductor element. . Then, a semiconductor device will be obtained through a wire bond process, a sealing process, etc. as needed.

  However, in order to manufacture a semiconductor device by such an individual piece sticking method, a dedicated assembly device for cutting out an adhesive film and bonding it to a support member is necessary, and thus a method of using a conventional silver paste Compared to the above, the manufacturing cost is high and the work is complicated.

  On the other hand, when manufacturing a semiconductor device by the latter wafer back surface sticking method, it can manufacture in the following procedures, for example. First, after affixing an adhesive film on the back surface of the semiconductor wafer, the release substrate is peeled off, and a dicing tape is further affixed on the adhesive layer. This dicing tape usually has a configuration in which an adhesive layer is formed on a base film, and is used for holding a wafer during dicing. In the present invention, this dicing tape is sometimes referred to as an “adhesive film”. Then, the semiconductor element separated into pieces is produced by dicing a semiconductor wafer, the separated semiconductor element with the contact bonding layer is picked up, and it joins to a support member via an contact bonding layer. Then, a semiconductor device will be obtained through processes, such as heating, hardening, and wire bonding.

  When manufacturing a semiconductor device by such a wafer back surface pasting method, since the separation is performed after the adhesive film is pasted on the semiconductor wafer, an apparatus for separating the adhesive film is not required, and the conventional method is used. The assembly apparatus used in the method using the silver paste can be used as it is or by modifying a part of the apparatus such as adding a hot platen. Therefore, in the manufacturing method of the semiconductor device using an adhesive film, it attracts attention as a method which can hold down manufacturing cost comparatively cheaply.

  However, even in such a wafer back surface pasting method, two steps of a step of pasting the adhesive film to the semiconductor wafer and a step of pasting the adhesive film (dicing tape) to the adhesive layer before dicing the semiconductor wafer. It was necessary to perform an attaching process. For this reason, a die-bonded dicing sheet has been developed that has a configuration in which an adhesive film and an adhesive film are bonded together, and can be applied to both the adhesive film and the adhesive film in a single application process, thus simplifying the work. (For example, refer to Patent Document 1). A die bond dicing sheet having a single adhesive layer having both functions of an adhesive film and an adhesive film has also been proposed (for example, see Patent Document 2). In the present invention, the die bond dicing sheet having both functions of the adhesive film and the dicing tape is sometimes referred to as an “adhesive sheet”.

These adhesive sheets (die-bonded dicing sheets) are punched in advance according to the shape of the semiconductor wafer, the shape of the wafer ring used during dicing, etc., in order to make it easy to attach to the semiconductor wafer. A “pre-cut process” is performed in which the adhesive layer other than the part to which the wafer is attached is peeled off (see, for example, Patent Document 3).
Japanese Patent No. 2665383 JP 10-335271 A Japanese Utility Model Publication No. 6-18383

  This pre-cut adhesive sheet (die-bonded dicing sheet) is often stored in a reel-like state, and the release substrate serves as a carrier film during use, and the adhesive layer and adhesive The laminated body made of a film is peeled off from the peeling substrate before being attached to a semiconductor wafer or wafer ring.

  As the peeling method at this time, (1) a method in which the peeling end is lifted manually or by mechanical means, (2) a method in which air or the like is ejected to the peeling end, and (3) a wedge shape from the peeling substrate side. , By applying a plate-like or columnar member to bend the release substrate at an acute angle toward the member side, creating a release origin between the release substrate and the laminate comprising the adhesive layer and the adhesive film, and peeling (4) A method combining these may be considered.

  Among these methods, the methods (1) and (2) have a problem that it is difficult to automate the process and it is difficult to improve the efficiency of the work. On the other hand, the method (3) is preferable because it is easy to automate the process, but on the other hand, if the adhesion at the interface between the peeling substrate and the laminate is good, the peeling starting point can be made well. In some cases, peeling failure occurred. And, when trying to improve the occurrence of such a peeling failure by reducing the adhesion between the peeling substrate and the laminate, it is necessary to store the adhesive sheet or before attaching the laminate to the semiconductor wafer. There was a problem that peeling occurred between the peeling substrate and the laminate.

  The present invention has been made in view of the above-mentioned problems of the prior art, and sufficiently reduces the occurrence of peeling between a peeling substrate before use and a laminate comprising an adhesive layer and an adhesive film, An object of the present invention is to provide an adhesive sheet that can sufficiently reduce the occurrence of defective peeling in the step of peeling a body from a peeling substrate and attaching the body to a semiconductor wafer. Another object of the present invention is to provide a semiconductor device manufacturing method capable of efficiently manufacturing a semiconductor device using the adhesive sheet, and a semiconductor device manufactured by the manufacturing method.

  As a result of intensive studies to achieve the above object, the present inventors have found that the adhesive sheet has a specific range of thickness and tensile elastic modulus between the peeling substrate and the substrate film, and the peeling substrate. It has been found that the above-mentioned object can be achieved by the peel strength between the adhesive layer and the adhesive layer being in a specific range, and the present invention has been completed.

  That is, the present invention is an adhesive sheet having a configuration in which a release substrate, a thermosetting adhesive layer, a radiation curable adhesive layer, and a substrate film are sequentially laminated. It is partially formed on the substrate, the adhesive layer covers the adhesive layer, and is formed so that the peripheral edge is in contact with the release substrate. The release substrate has a thickness of 3 to 100 μm, The tensile elastic modulus at 25 ° C. is 1000 MPa or more, the substrate film has a thickness of 20 to 300 μm, the tensile elastic modulus at 25 ° C. is 10 to 300 MPa, and 25 between the release substrate and the adhesive layer. An adhesive sheet having a 90 ° peel strength at 0.1 ° C. of 0.1 to 20 N / m is provided.

  Here, the above “tensile modulus” is measured according to JIS K7113. Specifically, a sample having a width of 4 mm and a length of 20 mm is obtained using a DVE Rheospector DVE-V14 manufactured by Rheology. The storage elastic modulus was measured under the conditions of a measurement temperature of 25 ° C. and a frequency of 10 hz.

  The “90 ° peel strength” is measured according to JIS K6854-1, and specifically, an adhesive sheet having a width of 20 mm and a length of 80 mm is used as a sample. The force when the pressure-sensitive adhesive layer is pulled up to 90 ° at a measurement speed of 50 mm / min in a state where is fixed is measured by an autograph AGS-G manufactured by Shimadzu Corporation.

  According to the adhesive sheet, the pressure-sensitive adhesive layer covers the adhesive layer, and the peripheral portion is formed so as to be in contact with the peeling substrate, and the 90 ° peel strength between the pressure-sensitive adhesive layer and the peeling substrate is described above. By being in the range, occurrence of peeling between the peeling substrate and the laminate before use can be sufficiently reduced.

  Moreover, according to the said adhesive sheet, while each of a peeling base material and a base film has the tensile elasticity modulus of the range mentioned above, it has the thickness of the range mentioned above, From a peeling base material, it is a laminated body. When peeling the film, a peeling starting point can be easily created between the peeling substrate and the adhesive layer. Furthermore, when the 90 ° peel strength between the pressure-sensitive adhesive layer and the release substrate is in the above-described range, the pressure-sensitive adhesive layer can be easily peeled from the release substrate. From these things, according to the said adhesive sheet, it becomes possible to peel a laminated body from a peeling base material easily, and generation | occurrence | production of a peeling defect can fully be reduced.

  At this time, if the rigidity of the peeling substrate is lower than the rigidity of the substrate film due to the balance of the tensile modulus and thickness of the peeling substrate and the substrate film, the peeling substrate and the adhesive layer It tends to be possible to create a peeling start point more easily. And when peeling a laminated body from a peeling base material, there exists a tendency which can fully reduce generation | occurrence | production of peeling defect. For example, when a material in which a hard layer (a layer having relatively high rigidity) and a soft layer (a layer having a relatively low rigidity) are laminated is folded so that the soft layer faces inward, the soft layer is It is considered that the effect obtained based on the property that the two layers easily peel off because the hard layer tries to maintain the shape while being easily folded. This effect is obtained when peeling the laminate from the release substrate by applying a wedge-shaped, plate-like or columnar member from the release substrate side and bending the release substrate to the member side at an acute angle. It can be obtained particularly effectively.

  Moreover, in the said adhesive sheet, it is preferable that the thickness of a peeling base material is thinner than the thickness of a base film. Thereby, peeling of a laminated body from a peeling base material becomes easier, and generation | occurrence | production of peeling defect is fully reduced more.

  Furthermore, it is preferable that the said adhesive sheet is what the adhesive force between an adhesion layer and an adhesion layer falls, when a radiation is irradiated to an adhesion layer. This reduces the adhesive force between the adhesive layer and the adhesive layer by irradiating the adhesive layer with radiation when the adhesive film is peeled from the adhesive layer after the laminated body is attached to the semiconductor wafer and diced. By making it, it becomes possible to perform peeling easily.

  Moreover, this invention peels the laminated body which consists of an adhesive layer, an adhesion layer, and a base film from a peeling base material in the adhesive sheet of this invention mentioned above, and affixes a laminated body to a semiconductor wafer through an adhesive layer A step of obtaining a semiconductor wafer with a laminate, a step of dicing the semiconductor wafer with a laminate to obtain a semiconductor element with a laminate of a predetermined size, and irradiating the adhesive layer of the laminate with radiation to cure the adhesive layer The adhesive layer and the base film after curing are peeled from the adhesive layer to obtain the semiconductor element with the adhesive layer, and the semiconductor element with the adhesive layer is bonded to the support member for mounting the semiconductor element through the adhesive layer. And a method of manufacturing a semiconductor device, comprising:

  In such a manufacturing method, since the above-described adhesive sheet of the present invention is used, the peeling failure when the laminate is peeled off from the peeling substrate and attached to the semiconductor wafer is sufficiently reduced, and the semiconductor device is efficiently manufactured. Can be manufactured.

  Furthermore, the present invention provides a semiconductor device manufactured by the semiconductor device manufacturing method described above.

  According to the present invention, the occurrence of peeling between the peeling substrate before use and the laminate composed of the adhesive layer and the pressure-sensitive adhesive film is sufficiently reduced, and the laminate is peeled off from the peeling substrate and attached to the semiconductor wafer. In the attaching step, it is possible to provide an adhesive sheet that can sufficiently reduce the occurrence of peeling failure. Moreover, this invention can provide the manufacturing method of the semiconductor device which can manufacture a semiconductor device efficiently using the said adhesive sheet, and the semiconductor device manufactured by this manufacturing method.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description is omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios.

  FIG. 1 is a plan view showing an embodiment of the adhesive sheet of the present invention, and FIG. 2 is a schematic cross-sectional view when the adhesive sheet 1 shown in FIG. 1 is cut along the line AA in FIG. is there. As shown in FIGS. 1 and 2, the adhesive sheet 1 of the present invention has a release substrate 12, a thermosetting adhesive layer 14, a radiation curable adhesive layer 22, and a substrate film 24 sequentially laminated. It has the structure which was made. The adhesive layer 14 is partially formed on the release substrate 12. In the adhesive film 20 including the adhesive layer 22 and the substrate film 24, the adhesive layer 22 is formed so as to cover the adhesive layer 14. The peripheral portion of the adhesive layer 22 is formed in contact with the peeling substrate 12. Then, when the adhesive sheet 1 is used, the laminate 10 composed of the adhesive layer 14 and the pressure-sensitive adhesive film 20 is peeled off from the release substrate 12 and is attached to a semiconductor wafer or the like.

  Hereinafter, each layer which comprises the adhesive sheet 1 of this invention is demonstrated in detail.

(Peeling substrate)
The release substrate 12 plays a role as a carrier film when the adhesive sheet 1 is used. From the point that the release substrate 12 does not extend due to the tension during use, and easy to peel off from the laminate 10, The tensile elastic modulus at 25 ° C. needs to be 1000 MPa or more, preferably 2000 MPa or more, and more preferably 3000 MPa or more. The upper limit of the tensile modulus is not particularly limited, but is preferably 100,000 MPa or less, more preferably 50000 MPa or less from the viewpoint of improving workability.

  Moreover, the thickness of the peeling base material 12 needs to be 3-100 micrometers, it is preferable that it is 5-75 micrometers, and it is more preferable that it is 10-50 micrometers. When the adhesive sheet 1 is used, by applying a wedge-shaped, plate-shaped or columnar member from the release substrate 12 side, the release substrate 12 is bent at an acute angle toward the member side, and the release substrate 12 and the adhesive layer 22 The peeling starting point is formed during the peeling, but when the thickness of the peeling substrate 12 exceeds 100 μm, the peeling substrate 12 becomes so rigid that it becomes difficult to form an acute angle when it is bent, and a peeling defect is likely to occur. Further, when the thickness is less than 3 μm, there arises a problem that the strength of the peeling substrate 12 itself is lowered and the handling becomes difficult. From the viewpoint of rigidity at the time of peeling, it is preferable that the peeling substrate 12 is thinner, but from the problem of the strength of the peeling substrate 12 itself, the thickness of the peeling substrate 12 needs to be in the above range.

  Examples of such release substrate 12 include polyester films such as polyethylene terephthalate films, polytetrafluoroethylene films, polyethylene films, polypropylene films, polymethylpentene films, polyolefin films such as polyvinyl acetate films, and polyvinyl chloride. Plastic films such as films and polyimide films can be used.

  The release substrate 12 can be subjected to a surface treatment in order to control the adhesion between the thermosetting adhesive layer 14 and the radiation curable adhesive layer 22. Examples of such surface treatment include chemical surface treatment such as mold release treatment, coupling agent treatment and etching treatment, and physical surface treatment such as etching, vapor deposition and sputtering. Among these, a mold release treatment in which a mold release agent is applied is the most general, and silicone, fatty acid ester, phosphate ester, alcohol, fluorine, and other mold release agents can be used.

(Adhesive layer)
The adhesive layer 14 is a thermosetting adhesive layer that is cured by heat, and is a layer that contains at least a thermoplastic resin and a thermosetting resin in terms of heat resistance and adhesive strength after thermosetting. Is preferred.

  The thermoplastic resin is not particularly limited as long as it is a thermoplastic resin, or at least a resin that has thermoplasticity in an uncured state and forms a crosslinked structure after heating, but (a) Tg (glass transition temperature) ) Is a resin having a weight average molecular weight of 5,000 to 200,000, or (b) a resin having a Tg of -50 ° C. to 10 ° C. and a weight average molecular weight of 100,000 or more.

  Examples of the thermoplastic resin (a) include polyimide resin, polyamide resin, polyetherimide resin, polyamideimide resin, polyester resin, polyesterimide resin, phenoxy resin, polysulfone resin, polyethersulfone resin, polyphenylene sulfide resin, Examples thereof include polyether ketone resins, and among these, polyimide resins are preferable.

  As the thermoplastic resin (b), a polymer containing a functional monomer as a monomer unit is preferably used. Examples of the functional group of the functional monomer include glycidyl group, acryloyl group, methacryloyl group, hydroxyl group. , A carboxyl group, an isocyanurate group, an amino group, an amide group and the like. Among these, a glycidyl group is preferable. More specifically, a glycidyl group-containing (meth) acrylic copolymer containing a functional monomer such as glycidyl acrylate or glycidyl methacrylate as a monomer unit is preferable, and is incompatible with a thermosetting resin such as an epoxy resin. More preferably. In the present invention, the (meth) acrylic copolymer refers to both an acrylic copolymer and a methacrylic copolymer.

  As the glycidyl group-containing (meth) acrylic copolymer, for example, (meth) acrylic ester copolymer, acrylic rubber and the like can be used, and acrylic rubber is more preferable. The acrylic rubber is a rubber mainly composed of an acrylate ester and mainly composed of a copolymer such as butyl acrylate and acrylonitrile, a copolymer such as ethyl acrylate and acrylonitrile, or the like. In addition, as a specific example of a glycidyl group containing (meth) acrylic copolymer, Nagase ChemteX Co., Ltd. product, HTR-860P-3 (brand name) etc. are mentioned, for example.

  The amount of the epoxy resin-containing monomer unit such as glycidyl acrylate or glycidyl methacrylate contained in the adhesive layer 14 is preferably 0.5 to 6.0% by mass, and 0.5 to 5.0% by mass. More preferably, it is particularly preferably 0.8 to 5.0% by mass. When the amount of the glycidyl group-containing monomer unit is within this range, the adhesive force of the adhesive layer 14 can be sufficiently secured and gelation tends to be prevented.

  Examples of the functional monomer other than glycidyl acrylate and glycidyl methacrylate include ethyl (meth) acrylate and butyl (meth) acrylate, and these may be used alone or in combination of two or more. In the present invention, ethyl (meth) acrylate refers to both ethyl acrylate and ethyl methacrylate.

  The mixing ratio when two or more kinds of functional monomers are used in combination is determined in consideration of Tg of the glycidyl group-containing (meth) acrylic copolymer, and Tg is preferably −10 ° C. or higher. When Tg is −10 ° C. or higher, the tackiness of the adhesive layer 14 in the B-stage state is appropriate, and the handleability is good. The B stage state refers to a so-called semi-cured state of the resin in which the resin constituting the adhesive layer 14 has a certain degree of crosslinking in the resin.

  In the case of producing a high molecular weight component having a weight average molecular weight of 100,000 or more containing the functional monomer as a monomer unit by polymerizing the functional monomer, the polymerization method is not particularly limited. Methods such as polymerization (pearl polymerization) and solution polymerization can be used.

  In the present invention, the weight average molecular weight of the high molecular weight component containing a functional monomer as a monomer unit is 100,000 or more, preferably 300,000 to 3,000,000, and preferably 500,000 to 2,000,000. More preferred. When the weight average molecular weight is in this range, the strength, flexibility, and tackiness when sheet-like or film-like are appropriate, and the flowability is appropriate, so the circuit fillability of the wiring is sufficient. Can be secured. In the present invention, the weight average molecular weight is a value measured by gel permeation chromatography and converted using a standard polystyrene calibration curve.

  The thermosetting resin is not particularly limited as long as it is a resin that cures by heat and exhibits an adhesive action. For example, glycidyl group, acryloyl group, methacryloyl group, hydroxyl group, carboxyl group, isocyanurate group, amino group, amide The compound which has functional groups, such as group, is mentioned, These can be used individually or in combination of 2 or more types. More specifically, for example, epoxy resin, acrylic resin, silicone resin, phenol resin, thermosetting polyimide resin, polyurethane resin, melamine resin, urea resin, etc., especially heat resistance, workability, reliability Since an excellent adhesive sheet 1 can be obtained, it is most preferable to use an epoxy resin. When using an epoxy resin as the thermosetting resin, it is preferable to use an epoxy resin curing agent together.

  The epoxy resin is not particularly limited as long as it is cured and has an adhesive action. For example, a bifunctional epoxy resin such as a bisphenol A type epoxy resin, a novolak such as a phenol novolac type epoxy resin or a cresol novolac type epoxy resin. A type epoxy resin or the like can be used. Moreover, what is generally known, such as a polyfunctional epoxy resin, a glycidyl amine type epoxy resin, a heterocyclic ring-containing epoxy resin, or an alicyclic epoxy resin, can be used. These can be used alone or in combination of two or more.

  When using an epoxy resin, it is preferable to use an epoxy resin curing agent. As the epoxy resin curing agent, known curing agents that are usually used can be used, for example, amines, polyamides, acid anhydrides, polysulfides, boron trifluoride, dicyandiamide, bisphenol A, bisphenol F, bisphenol. Examples thereof include bisphenols having two or more phenolic hydroxyl groups in one molecule such as S, phenol resins such as phenol novolac resin, bisphenol A novolac resin or cresol novolac resin. Phenol resins such as phenol novolac resin, bisphenol A novolac resin, and cresol novolac resin are particularly preferable in terms of excellent electric corrosion resistance during moisture absorption. These epoxy resin curing agents can be used alone or in combination of two or more.

  Moreover, the usage-amount of the thermoplastic resin and thermosetting resin which comprises the adhesive bond layer 14 is that the usage-amount of a thermoplastic resin is 10-400 mass parts with respect to 100 mass parts of thermosetting resins. preferable. When it is in this range, the storage elastic modulus and the flowability during molding can be sufficiently ensured, and the handleability at high temperatures can be sufficiently obtained. In addition, the usage-amount of a thermoplastic resin has more preferable 15-350 mass parts, and its 20-300 mass parts is especially preferable.

  Furthermore, the thickness of the adhesive layer 14 is not particularly limited, but is preferably 5 to 250 μm. If the thickness is less than 5 μm, the stress relaxation effect tends to be poor, and if it exceeds 250 μm, it is not economical and tends to fail to meet the demand for miniaturization of the semiconductor device.

(Base film)
The pressure-sensitive adhesive film 20 includes a radiation curable pressure-sensitive adhesive layer 22 on a base film 24 that transmits radiation.

  The base film 24 constituting the pressure-sensitive adhesive film 20 has characteristics and the like required in the manufacturing process when manufacturing a semiconductor device using the adhesive sheet 1 (for example, whether or not to expand when picking up a semiconductor element). Depending on the material, the material and the like can be appropriately selected. Specifically, polyester films such as polyethylene terephthalate films, polytetrafluoroethylene films, polyethylene films, polypropylene films, polymethylpentene films, polyolefin films such as polyvinyl acetate films, plastics such as polyvinyl chloride films and polyimide films A film etc. are mentioned. Furthermore, the base film 24 may be one in which these films are laminated in two or more layers.

  The base film 24 needs to have a tensile elastic modulus at 25 ° C. of 10 to 300 MPa. When the tensile elastic modulus of the base film 24 is less than 10 MPa, the elongation is too large and handling becomes difficult, and a peeling failure when the laminate 10 is peeled from the peeling base 12 is likely to occur. If the tensile modulus exceeds 300 MPa, when the semiconductor device is manufactured using the adhesive sheet 1, the elongation of the base film 24 when picking up the semiconductor element becomes too small, causing a pickup failure of the semiconductor element. It becomes easy.

  Moreover, the thickness of the base film 24 needs to be 20-300 micrometers, it is preferable that it is 30-250 micrometers, and it is more preferable that it is 50-200 micrometers. If the thickness exceeds 300 μm, the entire thickness of the adhesive sheet 1 becomes too thick, which makes it difficult to handle at the time of use or to be stored in a reel shape. In addition, when the thickness is less than 20 μm, the rigidity of the base film 24 is reduced, and when the laminate 10 is peeled from the release base 12, peeling failure is likely to occur, and the strength of the base film 24 itself is increased. Since it falls, handling at the time of use of adhesive sheet 1 becomes difficult. The thickness of the base film 24 is greater when it is peeled off, and it is easier to peel off when it is peeled off. However, in the above-mentioned problems of handling during use or storage, or when manufacturing a semiconductor device, the semiconductor element Since the problem that the elongation of the base film 24 when picking up is reduced occurs, it is preferable to set the thickness within the above-described range.

  Moreover, it is preferable that the thickness of the base material film 24 is thicker than the thickness of the peeling base material 12 demonstrated previously. Thereby, when peeling the laminated body 10 from the peeling base material 12, it becomes easy to make the peeling starting point between the peeling base material 12 and the adhesion layer 22, and generation | occurrence | production of peeling defect can fully be suppressed.

(Adhesive layer)
The pressure-sensitive adhesive layer 22 constituting the pressure-sensitive adhesive film 20 is a layer containing, for example, a thermoplastic resin and a radiation curable compound, and a thermosetting resin or a compound that generates a base by irradiation with radiation as necessary. is there.

  As the thermoplastic resin, the thermoplastic resins mentioned in the description of the adhesive layer 14 can be used.

  The radiation curable compound is not particularly limited. For example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, -2-ethylhexyl acrylate, methacrylic acid-2- Ethylhexyl, pentenyl acrylate, tetrahydrofurfuryl acrylate, tetrahydrofurfuryl methacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, trimethylolpropane Diacrylate, trimethylolpropane triacrylate, trimethylolpro Dimethacrylate, trimethylolpropane trimethacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, pentaerythritol triacrylate, Pentaerythritol tetraacrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, styrene, divinylbenzene, 4-vinyltoluene, 4-vinylpyridine, N-vinylpyrrolidone, 2-hydroxy Ethyl acrylate, 2-hydroxyethyl methacrylate, 1,3-acryloyloxy-2-hydride Xipropane, 1,2-methacryloyloxy-2-hydroxypropane, methylenebisacrylamide, N, N-dimethylacrylamide, N-methylolacrylamide, triacrylate of tris (β-hydroxyethyl) isocyanurate, represented by the following general formula (1) A urethane (meth) acrylate compound comprising a compound represented by the following formula, a diol, an isocyanate compound represented by the following general formula (2) and a compound represented by the following general formula (3), represented by the following general formula (4) And a urea curable compound comprising an isocyanate compound represented by the following general formula (3) and a compound represented by the following general formula (5), and radiation curable having an ethylenically unsaturated group in the side chain A copolymer etc. are mentioned. These radiation curable compounds can be used alone or in combination of two or more.

［式中、Ｒ^１は水素原子又はメチル基を示し、ｑ及びｒは１以上の整数を示す。］

[Wherein, R ¹ represents a hydrogen atom or a methyl group, and q and r each represents an integer of 1 or more. ]

［式中、Ｒ^２は炭素数１〜３０の２価又は３価の有機基を示し、ｍは０〜１の整数を示す。］

[Wherein R ² represents a divalent or trivalent organic group having 1 to 30 carbon atoms, and m represents an integer of 0 to 1. ]

［式中、Ｒ^３は水素原子又はメチル基を示し、Ｒ^４はエチレン基又はプロピレン基を示す。］

[Wherein, R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents an ethylene group or a propylene group. ]

［式中、Ｒ^５は炭素数２〜３０の２価の有機基を示す。］

[Wherein R ⁵ represents a divalent organic group having 2 to 30 carbon atoms. ]

［式中、ｎは０〜１の整数を示す。］

[In formula, n shows the integer of 0-1. ]

  As said thermosetting resin, the thermosetting resin quoted in description of the contact bonding layer 14 can be used. Moreover, when using an epoxy resin as a thermosetting resin, it is preferable to use an epoxy resin hardening | curing agent as mentioned above.

  As the compound that generates a base upon irradiation with radiation, a compound that generates a base upon irradiation with radiation and the generated base increases the curing reaction rate of the thermosetting resin is used. Here, as the generated base, a strongly basic compound is preferable from the viewpoint of reactivity and curing rate. In general, a pKa value that is a logarithm of an acid dissociation constant is used as a basic index, and a base having a pKa value in an aqueous solution of 7 or more is preferable, and a base of 9 or more is more preferable.

  In addition, the compound that generates a base by irradiation with radiation is preferably a compound that generates a base by irradiation with light having a wavelength of 150 to 750 nm. In order to efficiently generate a base when using a general light source, More preferably, the compound generates a base upon irradiation with light of 250 to 500 nm.

  Examples of such compounds that generate a base upon irradiation include imidazole derivatives such as imidazole, 2,4-dimethylimidazole, and 1-methylimidazole, piperazine derivatives such as piperazine and 2,5-dimethylpiperazine, piperidine, 1 Piperidine derivatives such as 2-dimethylpiperidine, proline derivatives, trialkylamine derivatives such as trimethylamine, triethylamine, triethanolamine, 4-methylaminopyridine, 4-dimethylaminopyridine and the like, an amino group or an alkylamino group is at the 4-position Substituted pyridine derivatives, pyrrolidine derivatives such as pyrrolidine and n-methylpyrrolidine, alicyclic amine derivatives such as triethylenediamine and 1,8-diazabiscyclo (5,4,0) undecene-1 (DBU), Triethanolamine, benzyldimethylamine, and the like benzylamine derivatives such as benzyl diethylamine.

  Moreover, as a compound which generates a base by irradiation, for example, Journal of Photopolymer Science and Technology 12, 313-314 (1999) and Chemistry of Materials 11, 170-176 (1999) are described. Quaternary ammonium salt derivatives can be used. Since these produce highly basic trialkylamines by irradiation with actinic rays, they are optimal for curing epoxy resins. Furthermore, a carbamate derivative described in Journal of American Chemical Society 118, 12925 (1996), Polymer Journal 28, 795 (1996), or a primary amino group is generated by irradiation with active light. Oxime derivatives can also be used.

  As a compound that generates a base upon irradiation, an α-aminoketone compound can be most preferably used in the present invention. Specifically, 2-methyl-1 (4- (methylthio) phenyl) -2-morpholinopropan-1-one (product name: Irgacure 907, manufactured by Ciba Specialty Chemicals) commercially available as a photo radical generator. 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1-one (Ciba Specialty Chemicals, trade name: Irgacure 369), hexaarylbisimidazole derivative (halogen, alkoxy group, Substituents such as nitro and cyano groups may be substituted with phenyl groups), benzoisoxazolone derivatives, and the like.

  In addition to the above, a photopolymerizable monomer or oligomer, a photopolymerization initiator, a thermosetting resin curing agent, a curing accelerator, a filler, or the like can be used for the adhesive layer 22.

  The thickness of the adhesive layer 22 is not particularly limited, but is preferably 0.1 to 20 μm. If the thickness is less than 0.1 μm, the adhesive force between the radiation curable adhesive layer 22 and the base film is lowered, and the semiconductor element may be scattered during dicing. On the other hand, if the thickness exceeds 20 μm, the overall thickness of the adhesive sheet 1 becomes too thick, which makes it difficult to handle during use or to be stored in a reel shape. .

  As mentioned above, although each layer which comprises the adhesive sheet 1 was demonstrated in detail, the following materials can be further added to the adhesive layer 14 and / or the adhesion layer 22 among these.

  A curing accelerator can be further added to each of the thermosetting adhesive layer 14 and the radiation curable adhesive layer 22 constituting the adhesive sheet 1. Although it does not restrict | limit especially as a hardening accelerator, For example, imidazole etc. are mentioned. More specifically, examples include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, and the like. It can be used alone or in combination of two or more.

  When the curing accelerator is added, the addition amount is preferably 5 parts by mass or less and more preferably 3 parts by mass or less with respect to 100 parts by mass of the total amount of the thermosetting resin. When the addition amount exceeds 5 parts by mass, the storage stability tends to decrease.

  In addition, a photopolymerization initiator that generates free radicals upon irradiation with actinic light can be added to the radiation-curable pressure-sensitive adhesive layer 22 constituting the adhesive sheet 1. Examples of such a photopolymerization initiator include benzophenone, N, N′-tetramethyl-4,4′-diaminobenzophenone (Michler ketone), N, N′-tetraethyl-4,4′-diaminobenzophenone, 4- Methoxy-4′-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2,2-dimethoxy-1,2-diphenylethane-1-one, 1- Aromatic ketones such as hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-1- (4- (methylthio) phenyl) -2-morpholinopropanone-1, 2,4-diethylthioxanthone, 2-ethylanthraquinone, phenanthrenequinone , Benzoin methyl ether, benzoin ethyl ether, benzoin Benzoin ether such as nyl ether, benzoin such as methyl benzoin and ethyl benzoin, benzyl derivatives such as benzyl dimethyl ketal, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4 , 5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-phenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer 2-mer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2,4-dimethoxy) 2,4,5-triarylimidazole dimer such as phenyl) -4,5-diphenylimidazole dimer , 9-phenyl acridine, 1,7-bis (9,9'-acridinyl) including acridine derivatives heptane, and the like. These may be used alone or in combinations of two or more.

  Although the addition amount in the case of adding a photoinitiator is not restrict | limited, It is preferable that it is 0.01-30 mass parts with respect to 100 mass parts of total amounts of a radiation-curable compound.

  Further, as a method for increasing the storage elastic modulus of the thermosetting adhesive layer 14, for example, the use amount of an epoxy resin is increased, an epoxy resin having a high glycidyl group concentration, or a phenol resin having a high hydroxyl group concentration is used. The storage elastic modulus can be improved by increasing the crosslink density of the whole polymer or adding a filler.

  Further, a high molecular weight resin compatible with the thermosetting resin can be added to the thermosetting adhesive layer 14 for the purpose of improving flexibility and reflow crack resistance. Such a high molecular weight resin is not particularly limited, and examples thereof include a phenoxy resin, a high molecular weight thermopolymerizable resin, and an ultrahigh molecular weight thermopolymerizable resin. These can be used alone or in combination of two or more.

  The amount of these high molecular weight resins used is preferably 40 parts by mass or less with respect to 100 parts by mass of the total amount of the thermosetting resin. Within this range, the Tg of the adhesive layer 14 can be secured.

  Further, an inorganic filler is added to each of the thermosetting adhesive layer 14 and the radiation curable pressure-sensitive adhesive layer 22 for the purpose of improving the handleability, improving the thermal conductivity, adjusting the melt viscosity, and imparting thixotropic properties. be able to. The inorganic filler is not particularly limited. For example, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whisker, nitride Boron, crystalline silica, amorphous silica and the like can be mentioned, and the shape of the filler is not particularly limited. These fillers can be used alone or in combination of two or more. Among these, aluminum oxide, aluminum nitride, boron nitride, crystalline silica, amorphous silica, and the like are preferable for improving thermal conductivity. For the purpose of adjusting melt viscosity and imparting thixotropic properties, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, crystalline silica Amorphous silica and the like are preferable.

  When the inorganic filler is added, the addition amount is preferably 1 to 20% by mass with respect to 100% by mass of the total amount of the thermosetting adhesive layer 14 or the radiation curable adhesive layer 22. If the addition amount is less than 1% by mass, the addition effect tends to be insufficient, and if it exceeds 20% by mass, problems such as a decrease in the adhesiveness of the adhesive layer 14 or the adhesive layer 22 tend to occur. There is.

  In addition, various coupling agents can be added to each of the thermosetting adhesive layer 14 and the radiation curable adhesive layer 22 in order to improve interfacial bonding between different materials. Examples of the coupling agent include silane-based, titanium-based, and aluminum-based coupling agents, and among these, a silane-based coupling agent is preferable because of its high effect. These can be used alone or in combination of two or more.

  In the case of adding the coupling agent, the addition amount is preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the total amount of the thermopolymerizable resin from the viewpoint of the effect, heat resistance and cost.

  In addition, an ion scavenger can be added to the thermosetting adhesive layer 14 in order to adsorb ionic impurities and improve insulation reliability during moisture absorption. Such an ion scavenger is not particularly limited, for example, a triazine thiol compound, a bisphenol-based reducing agent, a compound known as a copper damage preventing agent that prevents copper from being ionized and dissolved, zirconium-based, antimony bismuth-based Examples include inorganic ion adsorbents such as magnesium aluminum compounds.

  In the case of adding an ion scavenger, the addition amount is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of the thermopolymerizable resin from the viewpoint of the effect of addition, heat resistance, cost, and the like.

  The adhesive sheet 1 includes a release substrate 12, an adhesive layer 14, an adhesive layer 22, and a substrate film 24 having the configuration as described above.

  In this adhesive sheet 1, the 90 ° peel strength between the peeling substrate 12 and the pressure-sensitive adhesive layer 22 needs to be 0.1 to 20 N / m. When the 90 ° peel strength exceeds 20 N / m, a peeling failure tends to occur when the adhesive layer 22 is peeled from the peeling substrate 12, and when it is less than 0.1 N / m, the peeling substrate during pre-cut processing. 12 and the adhesion layer 22 become easy to peel. Moreover, in order to more reliably prevent occurrence of peeling before use and occurrence of peeling during precut processing, the 90 ° peel strength is preferably 0.2 to 15 N / m, and preferably 0.5 to 10 N / m. More preferably, it is m. The 90 ° peel strength is preferably low in terms of ease of peeling, but in order to prevent peeling before use or during precut processing, the above range is preferred.

  Moreover, since the adhesive sheet 1 is particularly excellent in releasability, economy, film strength, and dicing properties, the thickness of the release substrate 12 is 10 to 50 μm, and the thickness of the substrate film 24 is 50 to 200 μm. And it is preferable that 90 degree peel strength is 0.5-10 N / m.

  When manufacturing the semiconductor device using the adhesive sheet 1, after dicing the semiconductor element to which the adhesive layer 14 and the adhesive film 20 are attached, the adhesive layer 22 is irradiated with radiation to cure the adhesive layer 22. The adhesive force at the interface between the adhesive layer 14 and the radiation curable pressure-sensitive adhesive layer 22 is reduced, thereby enabling the semiconductor element to be picked up.

  Such an adhesive sheet 1 is manufactured as follows, for example.

  First, the material constituting the thermosetting adhesive layer 14 is dissolved or dispersed in a solvent to form an adhesive layer forming varnish, which is applied onto the release substrate 12 and then the solvent is removed by heating to remove the adhesive layer 14. Form. Similarly, the material constituting the radiation curable pressure-sensitive adhesive layer 22 is dissolved or dispersed in a solvent to form a pressure-sensitive adhesive layer-forming varnish, which is coated on the base film 24, and then the solvent is removed by heating to remove the pressure-sensitive adhesive layer 20 Form.

  Here, the solvent used for the preparation of the varnish is not particularly limited as long as it can dissolve or disperse each constituent material, but considering volatility at the time of layer formation, for example, methanol, It is preferable to use a solvent having a relatively low boiling point such as ethanol, 2-methoxyethanol, 2-ethoxyethanol, 2-butoxyethanol, methyl ethyl ketone, acetone, methyl isobutyl ketone, toluene, and xylene. For the purpose of improving the coating properties, for example, a solvent having a relatively high boiling point such as dimethylacetamide, dimethylformamide, N-methylpyrrolidone and cyclohexanone can be used. These solvents can be used alone or in combination of two or more.

  In preparation of the varnish when an inorganic filler is added as a constituent material of each layer, it is preferable to use a raking machine, a three-roll, a ball mill, a bead mill or the like in consideration of the dispersibility of the inorganic filler. These can also be used in combination. Moreover, after mixing an inorganic filler and a low molecular weight material beforehand among the constituent materials of each layer, the mixing time can also be shortened by mix | blending a high molecular weight material. Moreover, after preparing a varnish, the bubble in a varnish can also be removed by vacuum deaeration.

  Moreover, as a coating method of the varnish to the peeling base material 12 and the base film 24, a well-known method can be used, for example, a knife coat method, a roll coat method, a spray coat method, a gravure coat method, a bar coat method A curtain coating method or the like can be used.

  Next, the adhesive layer 14 formed on the release substrate 12 as described above (hereinafter referred to as “adhesive film”) and the adhesive layer 22 formed on the substrate film 24 (adhesive film 20) Are bonded together so that the adhesive layer 14 covers the adhesive layer 22 and the peripheral portion of the adhesive layer 22 is in contact with the release substrate 12, thereby forming the adhesive sheet 1.

  Here, the bonding of the adhesive film and the pressure-sensitive adhesive film 20 can be performed by a conventionally known method, for example, using a laminator or the like.

  Moreover, the adhesive sheet 1 can also be manufactured by the following method. That is, after the adhesive layer forming varnish is applied on the release substrate 12, the solvent is removed by heating to form the adhesive layer 14, and then the adhesive layer forming varnish is applied on the adhesive layer 14 and heated to remove the solvent. A method for forming the adhesive layer 22 by removing the adhesive layer, after applying the adhesive layer forming varnish on the base film 24, removing the solvent by heating to form the adhesive layer 22, and then forming an adhesive layer on the adhesive layer 22 For example, a method of applying the forming varnish and removing the solvent by heating to form the adhesive layer 14 may be employed.

  Further, in order to obtain a desired sheet thickness as a whole, the adhesive sheet 1 sandwiches an adhesive layer formed by a conventionally known method between the thermosetting adhesive layer 14 and the radiation curable adhesive layer 22. It may be provided as follows. As the adhesive layer formed by a conventionally known method, a commercially available die bond dicing sheet, for example, a polyimide-based, silicon oligomer-based, rubber-epoxy-based, or epoxy-based adhesive can be used. However, it is necessary to consider a bonding condition that does not cause separation of the adhesive layers based on a conventionally known technique.

  When radiation is applied to the adhesive sheet having the configuration described above, the adhesive force at the interface between the thermosetting adhesive layer 14 and the radiation curable adhesive layer 22 is greatly reduced after irradiation. Therefore, when a semiconductor device is manufactured using the adhesive sheet 1, the semiconductor element to which the adhesive layer 14 is adhered can be easily picked up from the adhesive film 20 after dicing the semiconductor element.

  Here, as the radiation applied to cure the adhesive layer 22, for example, ultraviolet (UV) or electron beam (EB) can be used.

  Further, the adhesive layer 22 of the adhesive sheet 1 may be heated for the purpose of promoting the curing reaction at the same time as or after the radiation irradiation, in addition to the method of reducing the adhesive force only by the radiation irradiation. By using both radiation irradiation and heating, the adhesive force of the adhesive layer 22 can be reduced in a shorter time. The heating temperature is not particularly limited as long as it is not higher than the decomposition point of the pressure-sensitive adhesive layer 22 and the thermosetting adhesive layer 14 is not cured, but a temperature of 50 to 170 ° C. is preferable.

  Next, a method for manufacturing a semiconductor device using the adhesive sheet 1 described above will be described with reference to FIG.

  FIGS. 3A to 3C are explanatory views illustrating an example of a process of attaching the laminated body 10 of the adhesive sheet 1 to the semiconductor wafer 32. As shown in FIG. 3 (a), the adhesive sheet 1 has a peeling substrate 12 serving as a carrier film, and is supported by two rolls 62 and 66 and a wedge-shaped member 64, while one end of the adhesive sheet 1 is a circle. The first roll 42 is formed while being connected to the columnar core 44, and the second roll 52 is formed by being wound with the other end connected to the columnar core 54. Yes. A core driving motor (not shown) for rotating the core 54 is connected to the core 54 of the second roll 52, and the peeling base after the laminate 10 is peeled off. The material 12 is wound at a predetermined speed.

  First, when the winding core driving motor rotates, the winding core 54 of the second roll 52 rotates, and the adhesive sheet 1 wound around the winding core 44 of the first roll 42 is outside the first roll 42. Pulled out. The drawn adhesive sheet 1 is guided onto a disk-shaped semiconductor wafer 32 disposed on a movable stage and a wafer ring 34 disposed so as to surround the semiconductor wafer 32.

  Next, the laminate 10 composed of the adhesive layer 14 and the pressure-sensitive adhesive film 20 is peeled from the peeling substrate 12. At this time, the wedge-shaped member 64 is applied from the peeling substrate 12 side of the adhesive sheet 1, and the peeling substrate 12 is bent at an acute angle toward the member 64 side and peeled between the peeling substrate 12 and the laminate 10. A starting point will be created. Furthermore, air is blown to the boundary surface between the peeling substrate 12 and the laminate 10 so that the peeling starting point is more efficiently created.

  After the peeling starting point is created between the peeling substrate 12 and the laminate 10 in this way, as shown in FIG. 3B, the adhesive film 20 is in close contact with the wafer ring 34, and the adhesive layer 14 is a semiconductor. The laminated body 10 is attached so as to be in close contact with the wafer 32. At this time, the laminated body 10 is pressed against the semiconductor wafer 32 by the roll 68. And as shown in FIG.3 (c), the affixing of the laminated body 10 on the semiconductor wafer 32 is completed, and the semiconductor wafer with a laminated body is obtained.

  By the procedure as described above, the laminate 10 can be attached to the semiconductor wafer 32 continuously in an automated process.

  And when bonding the laminated body 10 to the semiconductor wafer 32 by such a process, the peeling origin between the peeling base material 12 and the laminated body 10 can be easily created by using the adhesive sheet 1 of the present invention. And the occurrence of defective peeling can be sufficiently suppressed.

  In addition, in order to more easily create a peeling starting point between the peeling substrate 12 and the laminate 10, the adhesiveness of the peeling substrate 12 / adhesive layer 14 interface and the peeling substrate / adhesive layer 22 interface is determined by adhesion. It is preferably smaller than the adhesiveness at the interface between the layer 14 / adhesive layer 22 and the interface between the adhesive layer 22 / base film 24, and the constituent materials of each layer are preferably selected so as to have such a relationship.

  Next, the semiconductor wafer with a laminated body obtained by the above process is diced to obtain a semiconductor element with a laminated body having a required size. Here, steps such as washing and drying may be further performed. At this time, since the semiconductor wafer 32 is sufficiently adhered and held on the laminated body 10 by the adhesive layer 14 and the adhesive layer 22, the semiconductor wafer does not fall off during each of the above steps.

  Next, radiation is irradiated to the adhesion layer 22 of the laminated body 10, and a part or most of the adhesion layer 22 is polymerized and cured. At this time, heating may be further performed as described above for the purpose of accelerating the curing reaction simultaneously with irradiation or after irradiation.

  The adhesive layer 22 is irradiated with radiation from the surface of the base film 24 where the adhesive layer 22 is not provided. Therefore, when UV is used as radiation, the base film 24 needs to be light transmissive. In addition, when using EB as a radiation, the base film 24 does not necessarily need to be light transmissive.

  After irradiation, the semiconductor element to be picked up is picked up by, for example, a suction collet. At this time, the semiconductor element to be picked up can be pushed up from the lower surface of the base film 24 by, for example, a needle rod. By curing the adhesive layer 22, the adhesive force between the semiconductor element and the adhesive layer 14 becomes larger than the adhesive force between the adhesive layer 14 and the adhesive layer 22. Peeling occurs at the interface between the adhesive layer 14 and the adhesive layer 22, and the semiconductor element with the adhesive layer in a state where the adhesive layer 14 is attached to the lower surface of the semiconductor element is picked up.

  The semiconductor element with the adhesive layer is placed on a support member for mounting the semiconductor element via the adhesive layer 14 and heated. The adhesive layer 14 exhibits an adhesive force by heating, and the bonding between the semiconductor element and the semiconductor element mounting support member is completed.

  Then, a semiconductor device is manufactured through a wire bonding process, a sealing process, and the like as necessary.

  FIG. 4 is a schematic cross-sectional view showing an embodiment of the semiconductor element of the present invention manufactured by the method for manufacturing a semiconductor device described above.

  As shown in FIG. 4, in the semiconductor device 100, two semiconductor elements with an adhesive layer composed of an adhesive layer 14 and a semiconductor element 72 are stacked on an organic substrate 70 serving as a support member for mounting a semiconductor element. A circuit pattern 74 and a terminal 76 are formed on the organic substrate 70, and the circuit pattern 74 and the two semiconductor elements 72 are connected to each other by wire bonds 78. And these are sealed with the sealing material 80, and the semiconductor device 100 is formed. This semiconductor device 100 is manufactured using the adhesive sheet 1 of the present invention by the above-described method for manufacturing a semiconductor device of the present invention.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

(Synthesis Example 1: Synthesis of acrylic polymer)
A 500 ml four-necked separable flask equipped with a stirrer, a dropping funnel, a thermometer and a condenser tube is charged with 126.0 g of 2-butanone and heated to 80 ° C. while blowing nitrogen gas at a flow rate of 100 ml / min. And kept warm for about 30 minutes. Thereafter, while maintaining the temperature at 80 ° C., 0.6 g of 2,2-azobis (isobutyronitrile) was added to 14.8 g of 2-butanone, 15.0 g of methacrylic acid, and 70. A solution dissolved in a mixed solution of 0 g of 2-ethylhexyl acrylate was added dropwise over 4 hours, and the mixture was kept warm for 2 hours. Then, 0.06 g of 2,2-azobis (isobutyronitrile) was added in an amount of 8.5 g. A solution dissolved in 2-butanone was added dropwise over 30 minutes, and the mixture was kept warm for 5.5 hours. As a result, an acrylic polymer having a weight average molecular weight of 60,000 (measured by gel permeation chromatography and converted using a standard polystyrene calibration curve) and a nonvolatile content of 40% by mass was obtained.

(Production Example 1: Production of laminated film)
100 parts by mass of the acrylic polymer synthesized in Synthesis Example 1, NK-ESTER BPE-200 (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.), 2,2-bis (4-methacryloxyethoxyphenyl) propane 22.05 Methyl ethyl ketone was added to a composition composed of parts by mass and 0.5 part by mass of 1-hydroxycyclohexyl phenyl ketone, and the mixture was stirred and mixed, followed by vacuum degassing to prepare a varnish for forming an adhesive layer. This adhesive layer-forming varnish was applied on a 75 μm-thick polyethylene terephthalate (PET) film (Teijin DuPont Films, Teijin Purex S31, elastic modulus at 25 ° C .: 5000 MPa) subjected to a release treatment. Heat-drying was performed at 100 ° C. for 5 minutes to form a radiation-curing pressure-sensitive adhesive layer having a thickness of 10 μm. This obtained the laminated film (thickness 85 micrometers) which consists of a PET film and an adhesion layer.

[Example 1]
First, 60 parts by mass of YDCN-703 (trade name, manufactured by Toto Kasei Co., Ltd., cresol novolac type epoxy resin, epoxy equivalent 220) as an epoxy resin, and XLC-LL (trade name, Mitsui Chemicals, Inc.) as a curing agent (Product made from phenol xylene glycol dimethyl ether condensate) 40 parts by mass, 1500 parts by mass of cyclohexanone was added and mixed by stirring to prepare a first varnish. Next, 1 part by mass of NUC A-189 (trade name, manufactured by Nihon Unicar Co., Ltd., γ-glycidoxypropyltrimethoxysilane) as a coupling agent and NCU A-1160 ( 1 part by mass of trade name, manufactured by Nihon Unicar Co., Ltd., and γ-ureidopropyltriethoxysilane), and the proportion of R972V (trade name, manufactured by Nippon Aerosil Co., Ltd., silica filler) in the total volume of the composition Was added so that it might become 10 volume%, and it stirred and mixed, Then, the 2nd varnish was prepared by performing a dispersion process with a bead mill. Next, 250 parts by mass of HTR-860-P3 (trade name, manufactured by Nagase ChemteX Corp., epoxy group-containing acrylic copolymer) and Curazole 2PZ-CN as a curing accelerator were added to the second varnish. 0.5 parts by mass (trade name, manufactured by Shikoku Kasei Co., Ltd., 1-cyanoethyl-2-phenylimidazole) was added and mixed by stirring to prepare an adhesive layer forming varnish.

  This adhesive layer-forming varnish was applied onto a 25 μm-thick polyethylene terephthalate (PET) film (Teijin DuPont Films, Teijin Purex A70, elastic modulus at 25 ° C .: 5000 MPa) subjected to a release treatment. Heat drying was performed at 140 ° C. for 5 minutes to form a thermosetting adhesive layer in a B stage state having a thickness of 20 μm. This obtained the adhesive film (thickness 45 micrometers) which consists of a PET film (peeling base material) and an contact bonding layer.

  In addition, the laminated film obtained in Production Example 1 and a Soft Touch SPA-01 having a thickness of 100 μm (trade name, manufactured by Tamapoly Co., Ltd., polyolefin film, elastic modulus at 25 ° C .: 200 MPa) were used with a laminator. Bonding was performed under the conditions of 25 ° C., linear pressure of 1 kg / cm, and speed of 0.5 m / min to obtain an adhesive film having a structure in which a soft touch (base film), an adhesive layer, and a PET film were sequentially laminated.

  The adhesive layer in the adhesive film produced as described above was precut to the size of a semiconductor wafer (φ220 mm), and the pressure-sensitive adhesive film produced as described above was precut to the size of a wafer ring (φ270 mm). Here, the precut was performed by roll cutting using a roll having a metal blade attached thereto.

  And after peeling a PET film from the adhesive film, the adhesive film after pre-cutting and the adhesive film after pre-cutting were joined under the conditions of 25 ° C., linear pressure 1 kg / cm, and speed 0.5 m / min. 1 adhesive sheet (die bond dicing sheet) was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Example 2]
Example 1 except that a release-treated polyethylene terephthalate (PET) film (manufactured by Teijin DuPont Films, Teijin Purex A70, elastic modulus at 25 ° C .: 5000 MPa) having a thickness of 38 μm was used as a release substrate. In the same manner as described above, an adhesive sheet of Example 2 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Example 3]
Example 1 except that a 75 μm-thick polyethylene terephthalate (PET) film (manufactured by Teijin DuPont Films, Teijin Purex A70, elastic modulus at 25 ° C .: 5000 MPa) was used as a release substrate. In the same manner as described above, an adhesive sheet of Example 3 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Example 4]
Using a polyethylene terephthalate (PET) film (Teijin DuPont Film Co., Ltd., Teijin Purex A70, elastic modulus at 25 ° C .: 25 MPa) having a thickness of 50 μm as a release substrate, as a substrate film, Adhesive sheet of Example 4 in the same manner as Example 1 except that Soft Touch SPA-01 having a thickness of 250 μm (trade name, manufactured by Tamapoly Co., Ltd., polyolefin film, elastic modulus at 25 ° C .: 200 MPa) was used. Got. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Example 5]
Example except that a 50 μm-thick polyimide (PI) film (manufactured by Ube Industries, Upilex, elastic modulus at 25 ° C .: 9000 MPa) having a silicone-based release agent applied to the surface was used as a peeling substrate. In the same manner as in Example 1, an adhesive sheet of Example 5 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Example 6]
Example except that a 25 μm-thick polyimide (PI) film (Ube Industries, Upilex, elastic modulus at 25 ° C .: 9000 MPa) having a silicone-based release agent applied to the surface was used as a peeling substrate. In the same manner as in Example 1, an adhesive sheet of Example 6 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Example 7]
Example 1 except that a 75 μm thick polyethylene film (made by Tamapoly Co., Ltd., HD, elastic modulus at 25 ° C .: 1400 MPa) having a silicone-based release agent applied to the surface was used as the peeling substrate. Thus, an adhesive sheet of Example 7 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Example 8]
Using a polyethylene terephthalate (PET) film (Teijin DuPont Film Co., Ltd., Teijin Purex A31, elastic modulus at 25 ° C .: 25 MPa) having a thickness of 50 μm as a release substrate, Adhesive sheet of Example 8 in the same manner as in Example 1 except that 100 μm thick Dynasoft (trade name, manufactured by Nigo Shoji Co., Ltd., polyolefin film, elastic modulus at 25 ° C .: 100 MPa) was used. Got. The 90 ° peel strength between the release substrate and the adhesive layer was 1 N / m.

[Comparative Example 1]
As in Example 1, except that a polyethylene terephthalate (PET) film having a thickness of 38 μm (manufactured by Teijin DuPont Films, Teijin Purex A635, elastic modulus at 25 ° C .: 5000 MPa) was used as the peeling substrate. The adhesive sheet of Comparative Example 1 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 30 N / m.

[Comparative Example 2]
Example 1 except that a 125 μm-thick polyethylene terephthalate (PET) film (manufactured by Teijin DuPont Films, Teijin Purex A70, elastic modulus at 25 ° C .: 5000 MPa) was used as a release substrate. In the same manner as described above, an adhesive sheet of Comparative Example 2 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Comparative Example 3]
Example 1 except that a 75 μm-thick polyethylene film (manufactured by Tamapoly Co., Ltd., HS-30, elastic modulus at 25 ° C .: 800 MPa) having a silicone-based release agent applied to the surface was used as the peeling substrate In the same manner as described above, an adhesive sheet of Comparative Example 3 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 5 N / m.

[Comparative Example 4]
Example 1 except that a 50 μm-thick polyethylene terephthalate (PET) film (manufactured by Teijin DuPont Films, Teijin Purex A30, elastic modulus at 25 ° C .: 5000 MPa) was used as the release substrate. In the same manner, an adhesive sheet of Comparative Example 4 was obtained. The 90 ° peel strength between the release substrate and the adhesive layer was 0.05 N / m.

(Evaluation of peeling failure)
The peeling defect at the time of peeling the laminated body which consists of an adhesive layer and an adhesive film from the peeling base material of the adhesive sheet obtained in Examples 1-8 and Comparative Examples 1-4 was evaluated as follows. First, 50 adhesive sheets of Examples 1 to 8 and Comparative Examples 1 to 4 (adhesive sheets in which 50 laminates composed of an adhesive film and an adhesive layer were formed on one release substrate) were prepared. And the operation | work which affixes the adhesive sheet of Examples 1-8 and Comparative Examples 1-4 on the semiconductor wafer was performed in the procedure similar to the procedure demonstrated using Fig.3 (a)-(c). At this time, the case where the laminate was not peeled off from the peeling substrate and was not attached to the semiconductor wafer was regarded as a peeling failure, and the number of peeling failures was determined. The results are shown in Table 1. Moreover, although the adhesive sheet of Examples 1-8 and Comparative Example 1 did not peel a laminated body from a peeling base material before performing the operation | work which sticks a laminated body to a semiconductor wafer, Comparative Examples 2-4 This adhesive sheet sometimes peeled off the laminate from the release substrate before the operation of attaching the laminate to the semiconductor wafer.

  As is clear from the results shown in Table 1, the adhesive sheets of Examples 1 to 8 were more peeled between the release substrate and the laminate before use than the adhesive sheets of Comparative Examples 1 to 4. Was sufficiently reduced, and it was confirmed that the occurrence of peeling failure when the laminate was peeled from the peeling substrate and attached to a semiconductor wafer was sufficiently reduced.

It is a top view which shows one Embodiment of the adhesive sheet of this invention. It is a schematic cross section at the time of cut | disconnecting the adhesive sheet 1 shown in FIG. 1 along the AA line of FIG. (A)-(c) is explanatory drawing which shows an example of the process of affixing the laminated body 10 on the semiconductor wafer 32. FIG. It is a schematic cross section which shows one Embodiment of the semiconductor element of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Adhesive sheet (die-bond dicing sheet), 10 ... Laminated body, 12 ... Peeling base material, 14 ... Adhesive layer, 20 ... Adhesive layer film, 22 ... Adhesive layer, 24 ... Base film, 32 ... Semiconductor wafer, 34 ... Wafer ring, 36 ... Stage, 42 ... First roll, 44 ... Core, 52 ... Second Roll, 54 ... winding core, 60 ... support roll, 70 ... organic substrate, 72 ... semiconductor element, 74 ... circuit pattern, 76 ... terminal, 78 ... wire bond, 80: Sealing material.

Claims (5)

An adhesive sheet having a configuration in which a release substrate, a thermosetting adhesive layer, a radiation curable adhesive layer, and a substrate film are sequentially laminated,
The adhesive layer is partially formed on the release substrate,
The pressure-sensitive adhesive layer covers the adhesive layer, and is formed so that a peripheral edge is in contact with the release substrate,
The release substrate has a thickness of 3 to 100 μm and a tensile elastic modulus at 25 ° C. of 1000 MPa or more.
The base film has a thickness of 20 to 300 μm and a tensile elastic modulus at 25 ° C. of 10 to 300 MPa,
90. Peel strength at 25 ° C. between the release substrate and the adhesive layer is 0.1 to 20 N / m.   The adhesive sheet according to claim 1, wherein a thickness of the release substrate is thinner than a thickness of the substrate film.   The adhesive sheet according to claim 1 or 2, wherein an adhesive force between the adhesive layer and the adhesive layer is reduced by irradiating the adhesive layer with radiation. The adhesive sheet according to any one of claims 1 to 3, wherein a laminate comprising the adhesive layer, the pressure-sensitive adhesive layer, and the base film is peeled from the release substrate, and the laminate is A process of obtaining a semiconductor wafer with a laminated body by attaching to a semiconductor wafer via an adhesive layer;
Dicing the semiconductor wafer with the laminate, and obtaining a semiconductor element with a laminate of a predetermined size;
Irradiating the adhesive layer of the laminate with radiation to cure the adhesive layer, peeling the adhesive layer and the base film after curing from the adhesive layer, and obtaining a semiconductor element with an adhesive layer;
Bonding the semiconductor element with an adhesive layer to a support member for mounting a semiconductor element via the adhesive layer;
A method for manufacturing a semiconductor device, comprising:   A semiconductor device manufactured by the method for manufacturing a semiconductor device according to claim 4.

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