JPWO2015141555A1 - Dicing sheet and chip manufacturing method using the dicing sheet - Google Patents

Abstract

A dicing sheet (1) comprising a substrate (2) and an adhesive layer (3) laminated on at least one surface of the substrate (2), wherein the adhesive layer (3) is energy polymerized. The pressure-sensitive adhesive layer (3) has a storage elastic modulus at 23 ° C. before irradiation with energy rays of 135,000 Pa or less, and the pressure-sensitive adhesive layer (3 For the dicing sheet (1) before irradiating the energy beam to), the adhesive strength measured when the 180 ° peeling adhesive strength test with respect to the stainless steel test plate is performed according to JIS Z0237: 2009 is 10 N / After irradiating the pressure-sensitive adhesive layer (3) of the dicing sheet (1) with energy rays, the dicing sheet (1) is subjected to a Gardner type mandrel bending tester, Based on the STM-D522, be tested bending diameter of the mandrel as 2 mm, it does not occur cracks in the pressure-sensitive adhesive layer after irradiation with energy beams (3).

Description

  The present invention relates to a dicing sheet used when manufacturing a chip which is a member formed by dividing a semiconductor-related member such as a silicon wafer with a protective film or a semiconductor package, and a method for manufacturing a chip using the dicing sheet About.

  An example of a method for manufacturing a chip from a semiconductor-related member such as a silicon wafer with a protective film or a semiconductor package is as follows. First, on one surface of the semiconductor-related member (in the case where the semiconductor-related member is a member having a silicon wafer, the surface opposite to the circuit forming surface of the silicon wafer is the surface) and the base material and the adhesive layer The semiconductor-related member is fixed to the dicing sheet by attaching a pressure-sensitive adhesive sheet (referred to as “dicing sheet” in this specification).

  Next, the semiconductor-related member fixed to the dicing sheet is cut and separated (diced) using a rotary blade or the like to divide into pieces, and a member in which a plurality of chips are arranged close to each other on the dicing sheet is produced. (Dicing process).

  Subsequently, the dicing sheet in this member is expanded (extends in the main surface direction) to widen the interval between the chips arranged on the dicing sheet (expanding process). The chips thus separated from each other on the dicing sheet are individually picked up, separated from the dicing sheet (pickup process), and transferred to the next process.

  By performing the step of reducing the adhesiveness of the pressure-sensitive adhesive layer after the completion of the dicing step and before the pickup step, the workability of the pickup step is improved. Due to the process of reducing the tackiness, the pressure-sensitive adhesive layer of the dicing sheet is usually designed so that the tackiness is lowered by a specific stimulus. As the specific stimulus, for example, energy rays such as ultraviolet rays and electron beams are used. Irradiation is employed.

  In the dicing process and the expanding process, an external force is applied between the chip formed by dividing the semiconductor-related member and the adhesive layer of the dicing sheet. It is desirable that a phenomenon in which the chip is peeled off from the pressure-sensitive adhesive layer by this external force (this phenomenon is also referred to as “chip scattering” in this specification) is difficult to occur.

  By the way, when the semiconductor-related member provided for the dicing process includes a protective film, or when the semiconductor chip is a semiconductor package formed by resin-sealing, the protective film and the sealing resin are members for displaying information. May also be used. In other words, by performing laser marking processing on the surface of the protective film or sealing resin and forming irregularities on the surface, information related to semiconductor-related members and chips (for example, letters and symbols) can be visually recognized. It may be displayed as possible.

  When the pressure-sensitive adhesive layer of the dicing sheet is attached to the adherend surface having the uneven surface as described above, the pressure-sensitive adhesive is provided in a concave portion (also referred to as a “concave portion” in the present specification) of the adherend surface. Phenomenon in which the material constituting the adhesive layer remains in the recessed portion of the chip when the layer enters and the chip is picked up from the dicing sheet in the pickup process (this phenomenon is referred to as “substance remaining in the recessed portion” in this specification). There is a case where a problem occurs.

In relation to the substance remaining in the recessed portion, Patent Document 1 discloses that the cured resin layer is used when dicing a semiconductor device having a cured resin layer having an uneven resin surface by information recording on at least one surface. In the adhesive tape for dicing that is attached to the concavo-convex resin surface and used to fix the semiconductor device, the substrate film, and an energy ray-curable adhesive layer provided thereon, and An adhesive tape for dicing is disclosed in which the storage elastic modulus of the adhesive layer at a temperature of 25 ° C. before curing with energy rays is 1.0 × 10 ⁵ Pa or more.

JP 2005-277297 A

  The adhesive tape for dicing (dicing sheet) disclosed in Patent Document 1 is a concave portion of a material constituting the adhesive layer by increasing the storage elastic modulus of the adhesive layer in a state before being irradiated with energy rays. This prevents the material from entering into the recessed portion.

  The present invention provides a dicing sheet that can make it difficult to cause chip scattering during the dicing process and hardly cause substance residue in the recessed portion, and dicing from the viewpoint different from Patent Document 1. It aims at providing the manufacturing method of the chip | tip which uses a sheet | seat.

When the present inventors examined in order to achieve the said objective, the following knowledge was acquired.
(I) An upper limit is set for the storage elastic modulus at 23 ° C. (unit: Pa, also referred to as “storage elastic modulus before irradiation” in the present specification) of the pressure-sensitive adhesive layer before irradiation with energy rays, and energy rays Adhesive strength measured by a 180 ° peeling test with respect to a stainless steel test plate specified in JIS Z0237: 2009 (unit: N / 25 mm, in this specification, “adhesion before irradiation”) By providing a lower limit to the “force”, chip scattering can be made difficult to occur.
(II) By increasing the bending resistance of the pressure-sensitive adhesive layer after energy beam irradiation, it is possible to make it difficult for the substance to remain in the recessed portion. Such bending resistance can be evaluated by a bending test of the dicing sheet or a breaking elongation of the pressure-sensitive adhesive layer.

The present invention completed based on this knowledge is as follows.
(1) A dicing sheet comprising a base material and a pressure-sensitive adhesive layer laminated on at least one surface of the base material, wherein the pressure-sensitive adhesive layer is a compound having an energy ray polymerizable functional group The pressure-sensitive adhesive layer is formed from a pressure-sensitive adhesive composition containing a polymerizable compound (B), and the pressure-sensitive adhesive layer has a storage elastic modulus at 23 ° C. before irradiation with energy rays of 135,000 Pa or less. About the dicing sheet before irradiating the line, the adhesive strength measured when performing the 180 ° peel adhesive test on the stainless steel test plate in accordance with JIS Z0237: 2009 is 10 N / 25 mm or more, After irradiating the adhesive layer of the dicing sheet with an energy ray, the dicing sheet is subjected to a Gardner mandrel bending test. Using, dicing sheet based on ASTM-D522, be tested bending diameter of the mandrel as 2 mm, characterized in that the crack in the adhesive layer after the energy ray irradiation does not occur.

(2) The dicing sheet according to (1), wherein in the bending test, even when the diameter of the mandrel is 1 mm, the pressure-sensitive adhesive layer after irradiation with the energy beam does not crack.

(3) The dicing sheet according to (1) or (2), wherein the pressure-sensitive adhesive layer has a thickness of 25 μm or less.

(4) The pressure-sensitive adhesive composition further includes at least one of a main agent (A) and the energy polymerizable compound (B) includes a compound (B _A ) having a function as the main agent (A). The dicing sheet according to any one of (1) to (3), wherein

(5) The energy polymerizable compound (B) has a weight average molecular weight of 4,000 or less, and is composed of a monofunctional monomer and a polyfunctional monomer, and a monofunctional and polyfunctional oligomer having an energy ray polymerizable group. The compound ( _BD ) which has a storage elastic modulus adjustment function which consists of 1 type or 2 or more types chosen from these, Content of the said compound ( _BD ) in the said adhesive composition is in the said adhesive composition The dicing sheet according to (4), wherein the content is 35 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the substance having a function as the main agent (A).

(6) The pressure-sensitive adhesive composition comprises a storage modulus modifier (D) having a weight average molecular weight of 4,000 or less (a monofunctional monomer having a weight average molecular weight of 4,000 or less and having an energy ray polymerizable group and a polyfunctional monomer). The dicing sheet according to any one of (1) to (4) above, which contains a functional monomer and a compound consisting of one or more selected from the group consisting of monofunctional and polyfunctional oligomers). .

(7) The surface on the pressure-sensitive adhesive layer side of the dicing sheet according to any one of (1) to (6) is affixed to the surface of a semiconductor-related member, and the semiconductor-related member on the dicing sheet is cut. A method for manufacturing a device chip, which is divided into individual pieces to obtain a plurality of chips, wherein the surface of the semiconductor-related member to which the surface on the adhesive layer side of the dicing sheet is attached has a recess.

In the dicing sheet according to the present invention, the pre-irradiation storage elastic modulus of the pressure-sensitive adhesive layer is 135,000 Pa or less, and the pre-irradiation adhesive force is 10 N / 25 mm or more, so that chip scattering hardly occurs in the dicing process. Moreover, since the pressure-sensitive adhesive layer after irradiation with energy rays is excellent in bending resistance in the dicing sheet according to the present invention, the material constituting the pressure-sensitive adhesive layer that has entered the recessed portion is less likely to break between the pressure-sensitive adhesive layer during pickup. . Therefore, the dicing sheet according to the present invention is unlikely to cause a substance residue in the recessed portion.
Therefore, the use of the dicing sheet according to the present invention makes it difficult for problems to occur in the dicing process and the pick-up process, and it is possible to manufacture a chip having excellent quality with high productivity.

It is a schematic sectional drawing of the dicing sheet which concerns on one Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described.
As shown in FIG. 1, a dicing sheet 1 according to an embodiment of the present invention includes a base material 2 and a pressure-sensitive adhesive layer 3 laminated on one surface of the base material 2.

1. Base material The base material 2 of the dicing sheet 1 according to the present embodiment is not particularly limited as long as it is not broken in an expanding process or the like performed after the dicing process. Usually, a resin-based material is a main material. Consists of film. Specific examples of such films include ethylene-copolymer films such as ethylene-vinyl acetate copolymer films, ethylene- (meth) acrylic acid copolymer films, and ethylene- (meth) acrylic acid ester copolymer films; low density Polyethylene (LDPE) film, linear low density polyethylene (LLDPE) film, polyethylene film such as high density polyethylene (HDPE) film, polypropylene film, polybutene film, polybutadiene film, polymethylpentene film, ethylene-norbornene copolymer film, Polyolefin film such as norbornene resin film; Polyvinyl chloride film such as polyvinyl chloride film and vinyl chloride copolymer film; Polyethylene terephthalate film, Polybutylene tele Polyester film of tallate films; polyurethane film; polyimide film; polystyrene films; polycarbonate films; and fluorine resin film. Further, modified films such as these crosslinked films and ionomer films are also used. The substrate 2 may be a film made of one of these, or may be a laminated film in which two or more of these are combined. In addition, “(meth) acrylic acid” in the present specification means both acrylic acid and methacrylic acid. The same applies to other similar terms.

The film constituting the substrate 2 preferably includes at least one of an ethylene copolymer film and a polyolefin film.
It is easy to control the mechanical characteristics of an ethylene copolymer film in a wide range by changing the copolymerization ratio. For this reason, the base material 2 provided with an ethylene-type copolymer film is easy to satisfy | fill the mechanical characteristic calculated | required as a base material of the dicing sheet 1 which concerns on this embodiment. Moreover, since the ethylene-based copolymer film has relatively high adhesion to the pressure-sensitive adhesive layer 3, peeling at the interface between the substrate 2 and the pressure-sensitive adhesive layer 3 is less likely to occur when used as a dicing sheet.

  The ethylene copolymer film and the polyolefin film are components that adversely affect the properties as a dicing sheet (for example, in the case of a polyvinyl chloride film, the plasticizer contained in the film is transferred from the substrate 2 to the adhesive layer 3). And further distributed on the surface of the pressure-sensitive adhesive layer 3 opposite to the side facing the substrate 2 to reduce the adhesiveness of the pressure-sensitive adhesive layer 3 to the adherend). Since there are few, problems, such as the adhesiveness with respect to the adherend of the adhesive layer 3, fall, are hard to arise. That is, the ethylene copolymer film and the polyolefin film are excellent in chemical stability.

  The base material 2 may contain various additives such as pigments, flame retardants, plasticizers, antistatic agents, lubricants, fillers, and the like in a film mainly composed of the above-described resin-based material. Examples of the pigment include titanium dioxide and carbon black. Examples of the filler include organic materials such as melamine resin, inorganic materials such as silica, and metal materials such as nickel particles. The content of such additives is not particularly limited, but should be limited to a range in which the substrate 2 exhibits a desired function and does not lose smoothness and flexibility.

  In the case where ultraviolet rays are used as energy rays to be irradiated for curing the pressure-sensitive adhesive layer 3, it is preferable that the substrate 2 has transparency to the ultraviolet rays. In addition, when using an electron beam as an energy beam, it is preferable that the base material 2 has the transparency of an electron beam.

  Further, the surface of the substrate 2 on the pressure-sensitive adhesive layer 3 side (hereinafter also referred to as “substrate first surface”) is one or more selected from the group consisting of a carboxyl group and ions and salts thereof. It is preferred that a component having The above components in the substrate 2 and the components related to the pressure-sensitive adhesive layer 3 (components used for forming the pressure-sensitive adhesive layer 3 such as the component constituting the pressure-sensitive adhesive layer 3 and the crosslinking agent (C) are exemplified.) Can interact with each other chemically to reduce the possibility of delamination between them. The specific method for making such a component exist in the base material 1st surface is not specifically limited. The base material 2 itself is, for example, an ethylene- (meth) acrylic acid copolymer film, an ionomer resin film, etc., and the resin that constitutes the base material 2 is selected from the group consisting of carboxyl groups, and ions and salts thereof 1 You may have a seed | species or 2 or more types. As another method for causing the above components to be present on the first surface of the base material, the base material 2 is, for example, a polyolefin film, and the first surface side of the base material is subjected to corona treatment or provided with a primer layer. May be. Various coating films may be provided on the surface of the substrate 2 opposite to the substrate first surface.

  The thickness of the base material 2 is not limited as long as the dicing sheet 1 can function properly in each of the aforementioned steps. Preferably they are 20 micrometers or more and 450 micrometers or less, More preferably, they are 25 micrometers or more and 400 micrometers or less, Especially preferably, they are the range of 50 micrometers or more and 350 micrometers or less.

  The elongation at break of the substrate 2 in the present embodiment is preferably 100% or more, particularly preferably 200% or more and 1000% or less, as a value measured at 23 ° C. and a relative humidity of 50%. Here, in this specification, the elongation at break is the elongation ratio of the length of the test piece at the time of breaking the test piece to the original length in a tensile test based on JIS K7161: 1994 (ISO 527-1 1993). . The base material 2 having the elongation at break of 100% or more is not easily broken during the expanding step, and the device chip formed by cutting the semiconductor-related member is easily separated.

  In addition, the tensile stress at 25% strain of the base material 2 in this embodiment is preferably 5 N / 10 mm or more and 15 N / 10 mm or less, and the maximum tensile stress is preferably 15 MPa or more and 50 MPa or less. Here, the tensile stress at the time of 25% strain and the maximum tensile stress are measured by a test according to JIS K7161: 1994. When the tensile stress at 25% strain is less than 5 N / 10 mm or the maximum tensile stress is less than 15 MPa, after pasting a semiconductor-related member on the dicing sheet 1 and fixing it to a frame such as a ring frame, Since the base material 2 is soft, there is a concern that slack may occur, and this slack may cause a conveyance error. On the other hand, if the tensile stress at 25% strain exceeds 15 N / 10 mm or the maximum tensile stress exceeds 50 MPa, there is a concern that problems such as peeling of the dicing sheet 1 itself from the ring frame may easily occur during the expanding process. Is done. The elongation at break, the tensile stress at 25% strain, and the maximum tensile stress are values measured in the longitudinal direction of the original fabric in the substrate 2.

2. Adhesive Layer The adhesive layer 3 provided in the semiconductor-related member processing sheet 1 according to the present embodiment is formed from an adhesive composition containing an energy polymerizable compound (B) that is a compound having an energy ray polymerizable functional group. . Thereby, the adhesive layer 3 contains such a compound, and as will be described later, the physical properties of the adhesive layer 3 can be changed before and after the irradiation with energy rays.

This pressure-sensitive adhesive composition preferably satisfies at least one of further containing a main agent (A) and that the energy polymerizable compound (B) contains a compound (B _A ) having a function as the main agent (A). . In the case where the energy beam polymerizable compound (B) contains the compound (B _A ), the pressure-sensitive adhesive composition may not contain a component that becomes the main agent (A) separately from the compound (B _A ). The pressure-sensitive adhesive composition may further contain a crosslinking agent (C) or the like as necessary. Hereinafter, the component which comprises an adhesive composition is demonstrated.

(1) Main agent (A)
Although the kind of main ingredient (A) is not specifically limited, The thing which can provide suitable adhesiveness easily to an adhesive layer, especially the adhesive layer before irradiating an energy ray is preferable. Examples of the main agent (A) include rubber-based, acrylic-based, silicone-based, and polyvinyl ether-based resin materials. Hereinafter, the acrylic polymer (A1) which is a kind of acrylic material will be described in some detail.

  The pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 according to this embodiment may contain an acrylic polymer (A1). In the pressure-sensitive adhesive layer 3 formed from this pressure-sensitive adhesive composition, at least a part of the acrylic polymer (A1) may be contained as a cross-linked product by performing a cross-linking reaction with a cross-linking agent (C) described later. .

  As the acrylic polymer (A1), a conventionally known acrylic polymer can be used. The polystyrene-reduced weight average molecular weight (Mw) of the acrylic polymer (A1) is preferably 10,000 or more and 2,000,000 or less, preferably 100,000 or more and 1,500,000 or less, from the viewpoint of film-forming property at the time of coating. More preferred.

  In the present specification, the weight average molecular weight (Mw) of the component contained in the pressure-sensitive adhesive composition is a gel permeation when the component is a polymer and inevitably has a certain molecular weight distribution. This means the weight average molecular weight in terms of polystyrene measured by the chromatographic method (GPC) method (polystyrene standard), and the component has a specific structure and other components (by-products generated when the compound is produced) Etc.) means the molecular weight (formula weight) of the compound. The polystyrene-converted weight average molecular weight is measured by, for example, using a Tosoh column, TSKguardcolumn HXL-H, TSKgel GMHXL-L (two), TSKgel G2000HXL on a high-speed GPC device “HLC-8121GPC / HT” manufactured by Tosoh. The detector was used as a differential refractometer under the conditions of eluent: tetrahydrofuran, oven temperature: 40 ° C., sample concentration: 0.2% (w / v), flow rate 1.0 ml / min. Done.

  The glass transition temperature Tg of the acrylic polymer (A1) is preferably in the range of −70 ° C. or higher and 30 ° C. or lower, more preferably −60 ° C. or higher and 20 ° C. or lower. The glass transition temperature can be calculated from the Fox equation.

  The acrylic polymer (A1) may be a homopolymer formed from one type of acrylic monomer, or may be a copolymer formed from a plurality of types of acrylic monomers, It may be a copolymer formed from one or more types of acrylic monomers and monomers other than acrylic monomers. Specific types of the compound to be an acrylic monomer are not particularly limited, and specific examples include (meth) acrylic acid, (meth) acrylic acid ester, and derivatives thereof (acrylonitrile, etc.). Specific examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and decyl (meth). (Meth) acrylates having a chain skeleton such as acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate; cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentanyl ( (Meth) acrylates having a cyclic skeleton such as meth) acrylate, tetrahydrofurfuryl (meth) acrylate, imide acrylate, etc .; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate Having a hydroxyl group etc. (meth) acrylate; glycidyl (meth) acrylate, (meth) acrylates having a reactive functional group other than hydroxyl group such as N- methylaminoethyl (meth) acrylate. Examples of monomers other than acrylic monomers include olefins such as ethylene and norbornene, vinyl acetate, and styrene. When the acrylic monomer is alkyl (meth) acrylate, the alkyl group preferably has 1 to 18 carbon atoms.

  When the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 according to this embodiment contains a cross-linking agent (C) that can cross-link the acrylic polymer (A1) as described later, acrylic The kind of the reactive functional group which the system polymer (A1) has is not particularly limited, and may be appropriately determined based on the kind of the crosslinking agent (C). For example, when the crosslinking agent (C) is a polyisocyanate compound, examples of the reactive functional group that the acrylic polymer (A1) has include a hydroxyl group, a carboxyl group, and an amino group. Among these, when a crosslinking agent (C) is a polyisocyanate compound, it is preferable to employ | adopt as a reactive functional group a hydroxyl group with high reactivity with an isocyanate group. The method for introducing a hydroxyl group as a reactive functional group into the acrylic polymer (A1) is not particularly limited. As an example, the case where the acrylic polymer (A1) contains a structural unit based on an acrylate having a hydroxyl group such as 2-hydroxyethyl (meth) acrylate in the skeleton.

(2) Energy beam polymerizable compound (B)
The energy ray-polymerizable compound (B) contained in the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 according to the present embodiment has an energy ray-polymerizable group, and energy such as ultraviolet rays, electron beams, and X-rays. The specific configuration is not particularly limited as long as the polymerization reaction can be performed by irradiation of the line. When the energy beam polymerizable compound (B) is polymerized, the adhesiveness of the pressure-sensitive adhesive layer 3 is lowered, and the workability of the pickup process is improved. Until the energy beam is irradiated, the polymerization reaction of the energy beam polymerizable group does not substantially occur. Therefore, the pressure-sensitive adhesive layer 3 of the dicing sheet 1 according to this embodiment is in a state before the energy beam is irradiated. And an energy beam polymerizable compound (B).

  The kind of energy beam polymerizable group is not particularly limited. Specific examples thereof include a functional group having an ethylenically unsaturated bond such as a vinyl group or a (meth) acryloyl group. The energy beam polymerizable group is preferably a functional group having an ethylenically unsaturated bond, and among them, a (meth) acryloyl group is more preferable from the viewpoint of high reactivity when irradiated with energy rays.

  The molecular weight of the energy beam polymerizable compound (B) is not particularly limited. When the molecular weight is excessively small, there is a concern that the compound volatilizes during the manufacturing process, and at this time, the stability of the composition of the pressure-sensitive adhesive layer 3 is lowered. Therefore, the molecular weight of the energy beam polymerizable compound (B) is preferably 100 or more, more preferably 200 or more, and particularly preferably 300 or more, as the weight average molecular weight (Mw).

The energy ray-polymerizable compound (B) includes a compound having a function of reducing the storage elastic modulus of the pressure-sensitive adhesive layer before being irradiated with energy rays, that is, a compound (B _D ) having a storage elastic modulus adjusting function. May be. Such a compound (B _D ) has a weight average molecular weight (Mw) of 4,000 or less and is composed of a monofunctional monomer and a polyfunctional monomer having an energy ray polymerizable group, and a monofunctional and polyfunctional oligomer. The compound which consists of 1 type, or 2 or more types chosen from a group is illustrated. The compound (B _D ) can be positioned as a kind of storage elastic modulus modifier (D) described later.

The specific composition of the compound (B _D ) is not particularly limited. Specific examples of the compound (B _D ) include trimethylolpropane tri (meth) acrylate, ethoxylated isocyanuric acid tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, tetramethylolmethanetetra (meth) acrylate, pentaerythritol tri (Meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate, 1,4-butylene glycol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, dicyclopentadiene dimethoxydi (meth) acrylate, polyethylene glycol di (meth) acrylate, oligoe Ether (meth) acrylate, urethane (meth) acrylate oligomer, epoxy-modified (meth) acrylate, polyether (meth) acrylate. When the pressure-sensitive adhesive composition contains the acrylic polymer (A1) as the main agent (A), the compound (B _D ) is (meth) from the viewpoint of high compatibility with the acrylic polymer (A1). It preferably has an acryloyl group.

  The number of energy beam polymerizable groups that the energy beam polymerizable compound (B) has in one molecule is not limited, but is preferably a plurality, more preferably 3 or more, and particularly preferably 5 or more. . The upper limit of the number of energy beam polymerizable groups that the energy beam polymerizable compound (B) has in one molecule is preferably 16 or less, and more preferably 12 or less. When the weight average molecular weight (Mw) of the energy beam polymerizable compound (B) is small, the energy beam polymerizable compound (B) should be balanced by reducing the number of energy beam polymerizable groups in one molecule. Therefore, it tends to be easy to maintain the bending resistance of the pressure-sensitive adhesive layer 3 described later.

The content of the compound (B _D ) in the pressure-sensitive adhesive composition is the content of a substance having a function as the main agent (A) in the pressure-sensitive adhesive composition (in the case where the substance consists of the main agent (A), the main agent ( the content of a), the content of the later-described compounds (compound when B _a) consisting only of (B _a), the sum of these content when consisting main agent (a) and compound (B _a) ) It is preferable to set it as 35 to 200 mass parts with respect to 100 mass parts, and it is more preferable to set it as 45 to 120 mass parts. In the present specification, “part by mass” indicating the content of each component means an amount as a solid content. By setting the content of the compound (B _D ) in such a range, the storage elastic modulus at 23 ° C. of the pressure-sensitive adhesive layer 3 is set in the range described later in the state before the irradiation with the energy beam, and the adhesive is applied by the energy beam irradiation. It becomes easy to achieve both reducing the adhesiveness of the agent layer 3 appropriately. Moreover, it becomes easy to improve the bending resistance of the adhesive layer 3 described later.

The energy beam polymerizable compound (B) may contain a compound (B _A ) having a function as the main agent (A). Specific examples of the compound (B _A ) include a polymer having a structural unit having an energy ray polymerizable group in the main chain or side chain. In this case, since the compound (B _A ) has properties as the main agent (A), it has an advantage that the composition of the composition for forming the pressure-sensitive adhesive layer 3 is simplified.

The compound (B _A ) having the properties of the main agent (A) as described above can be prepared, for example, by the following method. Acrylic copolymer which is a copolymer comprising a structural unit based on (meth) acrylate and a structural unit based on alkyl (meth) acrylate containing a functional group such as hydroxyl group, carboxyl group, amino group, substituted amino group, and epoxy group By reacting a polymer with a compound having a functional group capable of reacting with the above functional group and an energy ray polymerizable group (for example, a group having an ethylenic double bond) in one molecule, an energy ray polymerizable group is reacted. An acrylic polymer to which is added can be obtained.

  Examples of the energy beam for curing the energy beam polymerizable compound (B) include ionizing radiation, that is, X-rays, ultraviolet rays, and electron beams. Among these, ultraviolet rays that are relatively easy to introduce irradiation equipment are preferable.

When ultraviolet rays are used as the ionizing radiation, near ultraviolet rays including ultraviolet rays having a wavelength of about 200 to 380 nm may be used for ease of handling. What is necessary is just to select suitably according to the kind of energy-beam polymeric compound (B) and the thickness of the adhesive layer 3, as a light quantity of an ultraviolet-ray, and is about 50-500 mJ / cm < ² > normally, and 100-450 mJ / cm < ² >. Is preferable, and 150 to 400 mJ / cm ² is more preferable. Moreover, ultraviolet illuminance is about 50-500 mW / cm < ² > normally, 100-450 mW / cm < ² > is preferable and 200-400 mW / cm < ² > is more preferable. There is no restriction | limiting in particular as an ultraviolet-ray source, For example, a high pressure mercury lamp, a metal halide lamp, UV-LED etc. are used.

  When an electron beam is used as the ionizing radiation, the acceleration voltage may be appropriately selected according to the type of the energy beam polymerizable compound (B) and the thickness of the pressure-sensitive adhesive layer 3, and usually an acceleration voltage of 10 to 1000 kV. It is preferable that it is a grade. Moreover, what is necessary is just to set an irradiation dose to the range which an energy-beam polymeric compound (B) hardens | cures appropriately, and is normally selected in the range of 10-1000 krad. The electron beam source is not particularly limited, and for example, various electron beam accelerators such as a Cockloft Walton type, a bandegraft type, a resonant transformer type, an insulated core transformer type, a linear type, a dynamitron type, and a high frequency type are used. be able to.

(3) Crosslinking agent (C)
As described above, the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 according to this embodiment contains a crosslinking agent (C) that can react with the main agent (A) such as the acrylic polymer (A1). May be. In this case, the pressure-sensitive adhesive layer 3 according to this embodiment contains a cross-linked product obtained by a cross-linking reaction between the main agent (A) and the cross-linking agent (C).

  The content of the crosslinking agent (C) is not particularly limited. From the viewpoint of easy formation of the crosslinked product, the content of the crosslinking agent (C) is preferably 0.02 parts by mass or more with respect to 100 parts by mass of the main agent (A). From the viewpoint of avoiding an excessively long curing period, the content of the crosslinking agent (C) is preferably 15 parts by mass or less with respect to 100 parts by mass of the main agent (A). Examples of the crosslinking agent (C) include, for example, epoxy compounds, isocyanate compounds, metal chelate compounds, aziridine compounds and other polyimine compounds, melamine resins, urea resins, dialdehydes, methylol polymers, metal alkoxides, metals Examples include salts. Among these, it is preferable that the crosslinking agent (C) is a polyisocyanate compound and / or a polyepoxy compound because the crosslinking reaction is easily controlled.

  The polyisocyanate compound is a compound having two or more isocyanate groups per molecule, for example, aromatic polyisocyanate such as tolylene diisocyanate, diphenylmethane diisocyanate, xylylene diisocyanate; dicyclohexylmethane-4,4 "-diisocyanate, bicycloheptane Alicyclic isocyanate compounds such as triisocyanate, cyclopentylene diisocyanate, cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, hydrogenated xylylene diisocyanate; isocyanates having a chain skeleton such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, lysine diisocyanate Can be mentioned.

  Also, biuret bodies, isocyanurate bodies of these compounds, adduct bodies that are reaction products of these compounds with non-aromatic low-molecular active hydrogen-containing compounds such as ethylene glycol, trimethylolpropane, castor oil, etc. A modified product of can also be used. The polyisocyanate compound may be one type or a plurality of types.

  The polyepoxy compound is a compound having two or more epoxy groups per molecule, for example, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, 1,3-bis (N, N-diglycidyl). Aminomethyl) toluene, N, N, N ′, N′-tetraglycidyl-4,4-diaminodiphenylmethane, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,6-diglycidyl n- Hexane, bisphenol A type epoxy compound, bisphenol F type epoxy compound and the like can be mentioned.

  When the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 according to this embodiment contains a cross-linking agent (C), an appropriate cross-linking accelerator is added depending on the type of the cross-linking agent (C). It is preferable to contain. For example, when the crosslinking agent (C) is a polyisocyanate compound, the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 preferably contains an organic metal compound-based crosslinking accelerator such as an organic tin compound. .

The pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 according to this embodiment has a weight average molecular weight (Mw) of 4,000 or less, and the storage elastic modulus of the pressure-sensitive adhesive layer before being irradiated with energy rays. It is preferable to contain the storage elastic modulus modifier (D) which is a compound having a function of lowering. The compound (B _D ) described above can be regarded as a storage elastic modulus modifier (D) and a compound having an energy ray polymerizable group. Examples of the storage modulus modifier ( _D ) other than the compound (B _D ) include tackifying resins and plasticizers. Specific examples of the tackifying resin include rosin-based adhesives such as rosin and derivatives thereof (specific examples include polymerized rosin, esterified rosin, polymerized rosin ester, disproportionated rosin, and hydrogenated resins thereof). tackifying resins; alpha pinene resins, beta-pinene resins, terpene phenol resins, terpene-based tackifying resins and copolymers of terpene and styrene; C ₅ petroleum resins, C ₉ petroleum resins, C 5 _/ C ₉ petroleum Examples thereof include petroleum resins such as resins and hydrogenated resins thereof; coumarone resins; alkylphenol resins; xylene resins. The storage elastic modulus modifier ( _D ) other than the compound (B _D ) is used for adjusting the storage elastic modulus of the pressure-sensitive adhesive layer 3 when the pressure-sensitive adhesive composition contains the compound (B _A ). When content with respect to the main ingredient (A) of a compound (B _D ) is reduced, it can be used for the purpose of compensating for this.

When the pressure-sensitive adhesive composition contains a storage elastic modulus modifier ( _D ) other than the compound (B _D ), the content of the storage elastic modulus modifier (D) in the pressure-sensitive adhesive composition (the substance is the compound (B _D ) in the case where it contains _D ), the total amount including this) is the content of the substance having the function as the main ingredient (A) in the pressure-sensitive adhesive composition (when the substance consists of the main ingredient (A) only) the content of (a), the content of the later-described compounds compounds when (B _a) consisting only of (B _a), the main agent (a) and the compound if consisting (B _a) and is of the content The total is preferably 35 to 200 parts by mass, more preferably 45 to 120 parts by mass with respect to 100 parts by mass.

(4) Other components In addition to the above components, the pressure-sensitive adhesive composition for forming the pressure-sensitive adhesive layer 3 included in the dicing sheet 1 according to this embodiment includes a photopolymerization initiator, a tackifier, a dye and a pigment. Various additives such as coloring materials such as flame retardants, fillers and antistatic agents may be contained.

  Here, the photopolymerization initiator will be described in some detail. Examples of photopolymerization initiators include photoinitiators such as benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, titanocene compounds, thioxanthone compounds, and peroxide compounds, and photosensitizers such as amines and quinones. 1-hydroxycyclohexyl phenyl ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyldiphenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, dibenzyl, diacetyl, β-chloranthraquinone 2,4,6-trimethylbenzoyldiphenylphosphine oxide and the like. When ultraviolet rays are used as energy rays, the irradiation time and irradiation amount can be reduced by blending a photopolymerization initiator.

(5) Physical properties, shape, etc. (5-1) Storage modulus before irradiation The pressure-sensitive adhesive layer 3 included in the dicing sheet 1 according to this embodiment has a storage modulus at 23 ° C. before irradiation with energy rays (this specification). (Also referred to as “storage elastic modulus before irradiation”) is 135,000 Pa or less. When the storage elastic modulus before irradiation satisfies this range, the material constituting the pressure-sensitive adhesive layer 3 easily spreads on the surface of the semiconductor-related member that is the adherend surface, and the dicing sheet 1 having excellent adhesiveness is obtained. . When the adherend surface has a recessed portion, the material constituting the pressure-sensitive adhesive layer 3 can also spread in the recessed portion, and the adhesiveness of the dicing sheet 1 to the semiconductor-related member is particularly increased. From the viewpoint of more stably increasing the adhesiveness of the dicing sheet 1 to the semiconductor-related member, the storage elastic modulus before irradiation is preferably 120,000 Pa or less, and more preferably 100,000 Pa or less.

  The lower limit of the storage elastic modulus before irradiation is not particularly limited. From the viewpoint of stably maintaining the shape of the pressure-sensitive adhesive layer 3, the storage elastic modulus before irradiation is preferably 10,000 Pa or more, and more preferably 20,000 Pa or more.

The storage elastic modulus before irradiation is the molecular weight and content of the main agent (A) such as the acrylic polymer (A1), and the degree of cross-linking when the main agent (A) is cross-linked using the cross-linking agent (C). In the case of containing a storage elastic modulus modifier (D) (may be a compound (B _D ) that can be regarded as one type thereof), it is controlled by changing the type and content thereof. can do.

  In addition, said storage elastic modulus before irradiation can be measured using a well-known viscoelasticity measuring apparatus (for example, "ARES" by a TA instrument company). In the measurement, as will be described later in the examples, a layered body having a thickness of about 1 mm made of the material constituting the pressure-sensitive adhesive layer 3 is used as a measurement object from the viewpoint of reducing variation in measurement results. preferable.

(5-2) Adhesive strength before irradiation About the dicing sheet 1 which concerns on one Embodiment of this invention in the state before irradiating an energy ray, according to JISZ0237: 2009, 180 degree peeling adhesive strength with respect to a stainless steel test plate The adhesive strength (adhesive strength before irradiation) measured when the test is performed is 10 N / 25 mm or more. Since the adhesive strength before irradiation is 10 N / 25 mm or more, the dicing sheet 1 according to an embodiment of the present invention is not limited to the case where the adherend surface is a surface of a protective film, but the adherend surface is sealed with a semiconductor package. Even in the case of a stop resin surface, problems such as chip scattering are less likely to occur in the dicing process. From the viewpoint of more stably reducing the possibility of problems in the dicing process, the pre-irradiation adhesive strength of the dicing sheet 1 according to an embodiment of the present invention is more preferably 15 N / 25 mm or more, and 20 N / 25 mm or more. More preferably, it is particularly preferably 25 N / 25 mm or more. The upper limit of the adhesive strength before irradiation of the dicing sheet 1 according to an embodiment of the present invention is not limited.

  Usually, when the adherend surface is the surface of the sealing resin of the semiconductor package, the adhesion to the adherend surface of the dicing sheet is likely to be lower than when the adherend surface is made of a protective film surface, The dicing sheet 1 according to an embodiment of the present invention has excellent adhesiveness even in this case. That is, the dicing sheet 1 according to an embodiment of the present invention is the same as the test for measuring the adhesive strength before irradiation, when the surface of the sealing resin of the semiconductor package is used as the deposition surface. The measured adhesive strength tends to be 1 N / 25 mm or more.

  In addition, about the dicing sheet 1 which concerns on one Embodiment of this invention in the state after irradiating an energy ray, when an adhesion strength test was done by said method by making a to-be-adhered surface into the surface of the sealing resin of a semiconductor package The adhesive force to be measured is not limited. The lower the adhesive strength, the better. Usually, it is less than 1 N / 25 mm, preferably 700 mN / 25 mm or less, and more preferably 500 mN / 25 mm or less.

(5-3) Flexibility The pressure-sensitive adhesive layer 3 of the dicing sheet 1 according to an embodiment of the present invention has excellent flex resistance. The bending resistance can be evaluated by the following bending test.

  After irradiating the dicing sheet 1 according to an embodiment of the present invention with energy rays, a bending test of the dicing sheet 1 with a mandrel diameter of 2 mm based on ASTM-D522 using a Gardner mandrel bending tester. When this is performed, the adhesive layer 3 is not cracked. Since the pressure-sensitive adhesive layer 3 of the dicing sheet 1 according to an embodiment of the present invention has such excellent bending resistance, the pressure-sensitive adhesive layer 3 is configured by pasting the dicing sheet 1 on the adherend surface. Even if the material enters the recessed portion of the adherend surface, the material is easily separated from the adherend surface together with the pressure-sensitive adhesive layer 3 when the dicing sheet 1 is peeled from the adherend surface. Therefore, it is difficult for the substance to remain in the recessed portion, and it is easy to maintain a state where the visibility of the display formed by the recessed portion is good.

  The dicing sheet 1 according to an embodiment of the present invention preferably does not cause cracks in the pressure-sensitive adhesive layer 3 after irradiation with energy rays, even if the diameter of the mandrel is 1 mm in the bending test. In this case, the pressure-sensitive adhesive layer 3 is adhered to the surface to be laser-marked for a long time (specific example is one week), and the material constituting the pressure-sensitive adhesive layer 3 is sufficiently covered. Even when it becomes a state where the concave portion of the landing surface is wet and spread, when the dicing sheet 1 is peeled off after reducing the adhesiveness of the pressure-sensitive adhesive layer 3 by irradiating energy rays, the concave portion It is easy to maintain a good visibility of the formed display.

  By preventing the pressure-sensitive adhesive layer 3 from being excessively cured by irradiation with energy rays, it becomes easy to improve the bending resistance of the pressure-sensitive adhesive layer 3. For example, the excessive curing of the pressure-sensitive adhesive layer 3 can be controlled by, for example, determining the number of energy beam polymerizable groups that the energy beam polymerizable compound (B) has in one molecule by the weight of the energy beam polymerizable compound (B). This can be achieved by adjusting the average molecular weight (Mw) so that it does not become too large. In addition, the energy beam polymerizable compound (B) is the above-mentioned compound (B_D), The compound (B_D) To the main agent (A) is reduced, it becomes easy to suppress excessive curing of the pressure-sensitive adhesive layer 3. Compound (B _DIf the storage elastic modulus of the pressure-sensitive adhesive layer 3 is not sufficiently reduced by reducing the content of the main component (A) in_DYou may use together storage elastic modulus modifier (D) other than.

(5-4) Thickness of adhesive layer The thickness of the adhesive layer 3 of the dicing sheet 1 which concerns on this embodiment is not limited. The thicker the pressure-sensitive adhesive layer 3 is, the less the problem of chip scattering occurs, and the thinner the pressure-sensitive adhesive layer 3 is the problem caused by the pressure-sensitive adhesive adhering to the adherend in the dicing process (the generation of coarse adhered material is generated). Or a large amount of agglutinates). Further, when the pressure-sensitive adhesive layer 3 is excessively thick, there is a possibility that the substance remains in the recessed portion. An increase in the amount of substance remaining in the recessed portion is a factor that lowers the visibility of a print formed by a laser marking process or the like. From the viewpoint of preventing the occurrence of chip scattering and substance residue in the recessed portion, the thickness of the pressure-sensitive adhesive layer 3 of the dicing sheet 1 according to this embodiment is preferably 2 μm or more and 30 μm or less, and is 5 μm or more and 25 μm or less. More preferably, it is 7 μm or more and 15 μm or less.

(5-5) Release Sheet The dicing sheet 1 according to the present embodiment is for the purpose of protecting the pressure-sensitive adhesive layer 3 until the pressure-sensitive adhesive layer 3 is applied to a semiconductor-related member that is an adherend. The release surface of the release sheet may be bonded to the surface opposite to the side facing the first substrate surface. The configuration of the release sheet is arbitrary, and examples include a release film of a plastic film with a release agent. Specific examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene. As the release agent, silicone-based, fluorine-based, long-chain alkyl-based, and the like can be used, and among these, a silicone-based material that is inexpensive and provides stable performance is preferable. Although there is no restriction | limiting in particular about the thickness of a peeling sheet, Usually, it is about 20 micrometers or more and 250 micrometers or less.

3. Manufacturing method of dicing sheet The manufacturing method of the dicing sheet 1 is not particularly limited as long as the pressure-sensitive adhesive layer 3 formed from the above-described pressure-sensitive adhesive composition can be laminated on one surface of the substrate 2. For example, the pressure-sensitive adhesive composition described above and, if desired, a coating composition further containing a solvent are prepared, and a die coater, curtain coater, spray coater, slit coater, The pressure-sensitive adhesive layer 3 can be formed by applying the coating composition with a knife coater or the like to form a coating film and drying the coating film on the one surface. The properties of the coating composition are not particularly limited as long as it can be applied. The composition for forming the pressure-sensitive adhesive layer 3 may be contained as a solute, or may be contained as a dispersoid. There is also.

  When the coating composition contains a cross-linking agent (C), changing the drying conditions (temperature, time, etc.) described above, or providing a heat treatment separately, What is necessary is just to advance the crosslinking reaction of a coalescence (A1) and a crosslinking agent (C), and to form a crosslinked structure in the adhesive layer 3 with desired presence density. In order to sufficiently advance this crosslinking reaction, after the pressure-sensitive adhesive layer 3 is laminated on the base material 2 by the above-described method or the like, the obtained dicing sheet 1 is placed in an environment of, for example, 23 ° C. and a relative humidity of 50%. It is usually cured for a day.

  As another example of the manufacturing method of the dicing sheet 1, the coating composition is applied on the release surface of the release sheet to form a coating film, which is dried to form the adhesive layer 3 and the release sheet. A layered product is formed, and the surface opposite to the side facing the release sheet in the pressure-sensitive adhesive layer 3 of the layered product is pasted on the first surface of the base material 2, and the dicing sheet 1 and the release sheet A laminate may be obtained. The release sheet in this laminate may be peeled off as a process material, or may protect the pressure-sensitive adhesive layer 3 until being attached to the semiconductor package.

4). Chip Manufacturing Method A method of manufacturing a chip from a semiconductor-related member will be described below by taking as an example a case where a mold chip is manufactured from a semiconductor package using the dicing sheet 1 according to the present embodiment. In this specification, “semiconductor-related member” means a material used in semiconductor manufacturing, for example, semiconductor wafers such as silicon, SiC, and GaN, ceramic substrates such as alumina and sapphire, semiconductor packages, and glass members. Can be mentioned. “Semiconductor package” refers to an electronic component assembly in which semiconductor chips are mounted on each base of a base assembly and these semiconductor chips are collectively sealed with resin. “Mold chip” refers to a semiconductor component in which a semiconductor chip is sealed with resin.

  First, a semiconductor chip is mounted on each base of an assembly formed by connecting a plurality of bases such as a TAB tape, and these semiconductor chips are collectively sealed with a resin to obtain a semiconductor package. Next, the semiconductor package is fixed to the dicing sheet 1 by attaching the dicing sheet 1 according to the present embodiment to the surface of the semiconductor package on the side of the sealing resin. Specifically, the surface of the dicing sheet 1 on the pressure-sensitive adhesive layer 3 side (that is, the surface of the pressure-sensitive adhesive layer 3 on the side opposite to the base material 2) is attached to the surface of the sealing resin of the semiconductor package. The peripheral edge portion of the dicig sheet 1 is usually attached to an annular jig called a ring frame for conveyance and fixing to the apparatus by an adhesive layer 3 provided in that portion.

  Since the dicing sheet 1 according to this embodiment has the pre-irradiation storage modulus and the pre-irradiation adhesive force of the pressure-sensitive adhesive layer 3 controlled within appropriate ranges, the dicing sheet 1 according to the present embodiment can also be applied to the adherend surface composed of the sealing resin surface. Easy to spread wet. Therefore, a dicing step, specifically, a semiconductor package fixed to the dicing sheet 1 is cut and separated (diced) into individual pieces, and a member in which a plurality of mold chips are arranged close to each other on the dicing sheet is produced. In the process, chip scattering hardly occurs.

  Subsequently, the dicing sheet in this member is expanded (extends in the main surface direction) to widen the interval between the mold chips arranged on the dicing sheet (expanding step). The mold chips thus separated from each other on the dicing sheet are individually picked up, separated from the dicing sheet (pickup process), and transferred to the next process.

  Before this pick-up process is started, the pressure-sensitive adhesive layer 3 of the dicing sheet 1 is irradiated with energy rays to reduce its adhesiveness. Since the pressure-sensitive adhesive layer 3 of the dicing sheet 1 according to the present embodiment is excellent in bending resistance after irradiation with energy rays, the surface of the sealing resin has a recessed portion formed by laser marking or the like. Even when the material constituting the layer 3 enters the recessed portion, when the dicing sheet 1 is peeled off, the material easily escapes from the recessed portion, and the substance remains in the recessed portion. Therefore, the chip manufactured by the chip manufacturing method according to the present embodiment (device chip in the above description) is easy to maintain a state in which the visibility of the display formed by the recessed portion is good, and is excellent in quality.

  The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

  EXAMPLES Hereinafter, although an Example etc. demonstrate this invention further more concretely, the scope of the present invention is not limited to these Examples etc.

[Example 1]
The following energy ray-polymerizable compound (B1) with respect to 100 parts by mass of an acrylic polymer as a main ingredient (composition ratio of 2-ethylhexyl acrylate / methyl acrylate / acrylic acid = 50/40/10, weight average molecular weight: 800,000) And 10 parts by mass of a cross-linking agent (“BHS 8515” manufactured by Toyochem Co., Ltd.) containing trimethylolpropane tolylene diisocyanate (TDI-TMP) is added, and a solution of an organic solvent. As a pressure-sensitive adhesive coating composition was obtained. This was applied onto a release film ("SP-PET 381031" manufactured by Lintec Corporation), and dried at 100 ° C for 1 minute. Next, the pressure-sensitive adhesive layer was transferred to the surface on the electron beam irradiation side of the 140 μm thick ethylene-methacrylic acid copolymer film irradiated with the electron beam to obtain a dicing sheet. The thickness of the pressure-sensitive adhesive layer after drying was 10 μm.

Energy ray polymerizable compound (B1): 10 functional urethane acrylate (“UV-1700B” manufactured by Nippon Synthetic Chemical Co., Ltd., molecular weight: 1700)
Energy ray polymerizable compound (B2): hexafunctional acrylate (Nippon Kayaku DPCA-120, molecular weight: 1946)
Energy ray polymerizable compound (B3): Trifunctional acrylate (“A-9300” manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight: 423)
Energy ray-polymerizable compound (B4): tetrafunctional acrylate (“AD-TMP” manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight: 466)
Energy ray polymerizable compound (B5): 3 to 4 functional urethane acrylate ("EXL810TL" manufactured by Dainichi Seika Co., Ltd., weight average molecular weight: 5000)

[Example 1-1]
In Example 1, a dicing sheet was obtained by performing the same operation as in Example 1, except that the pressure-sensitive adhesive layer was coated so that the thickness (thickness after drying) was 30 μm.

[Examples 2 to 6 and Comparative Examples 1 to 5]
In Example 1, except that the type of the energy beam polymerizable compound used for obtaining the coating composition and the blending amount thereof (blending amount with respect to 100 parts by mass of the main agent) were changed as shown in Table 1, The same operation as in Example 1 was performed to obtain a dicing sheet.

[Test Example 1] <Measurement of storage elastic modulus before irradiation>
A release sheet (“SP-PET 382120” manufactured by Lintec Co., Ltd.) in which a silicone release agent layer having a thickness of 0.1 μm was formed on one main surface of a base film made of polyethylene terephthalate having a thickness of 38 μm was prepared. Each of the coating compositions prepared in Examples and Comparative Examples was applied with a knife coater on the release surface of the release sheet. The obtained coating film was dried for 1 minute together with the release sheet in an environment of 100 ° C. for 1 minute to dry the coating film, and the pressure-sensitive adhesive layer formed from each coating composition (the finally obtained pressure-sensitive adhesive) The thickness of the layer was 40 μm.) And a plurality of laminates composed of release sheets were prepared. Using these laminates, the pressure-sensitive adhesive layer formed from each coating composition was bonded to a thickness of 800 μm, and the resulting pressure-sensitive adhesive layer laminate was punched into a circle having a diameter of 10 mm. The sample for measuring the viscoelasticity of the adhesive layer formed from the composition for coating was obtained. Using a viscoelasticity measuring device (“ARES” manufactured by TA Instruments Inc.), strain of a frequency of 1 Hz was applied to the above sample, storage elastic modulus of −50 to 150 ° C. was measured, and storage elastic modulus at 23 ° C. Was obtained as the storage elastic modulus before irradiation. The results are shown in Table 1.

[Test Example 2] <Adhesive strength before and after energy beam irradiation>
The adhesive strength of the dicing sheets obtained in Examples and Comparative Examples was measured as follows in accordance with JIS Z0237: 2009 (ISO 29862-29864: 2007).
A dicing sheet with a width of 25 mm and a length of 200 mm was pasted on the surface of the stainless steel test plate and stored in an environment of 23 ° C. and a relative humidity of 50%. After 20 minutes, a universal tensile tester (“TENSILON” manufactured by Orientec Co., Ltd.) / UTM-4-100 "), the adhesive strength of the dicing sheet was measured at a peeling speed of 300 mm / min and a peeling angle of 180 °, and the resulting adhesive strength was measured before the irradiation (unit: N / 25 mm). It was.
A semiconductor package (150 mm × 50 mm, thickness 600 μm, dicing sheet) formed by molding a sealing resin composition (“KE-G1250” manufactured by Kyocera Chemical Co., Ltd.) from the surface of the stainless steel test plate as the adherend surface of the above test. Adhesive strength was measured by the same method as described above except that the surface was changed to a sealing resin surface with an arithmetic average roughness Ra of 2 μm), and the resulting adhesive strength was measured as PKG adhesive strength (before irradiation) ( (Unit: mN / 25 mm).
The dicing sheets obtained in the examples and comparative examples were affixed to the surface of the sealing resin of the semiconductor package, and then left for 20 minutes in an atmosphere of 23 ° C. and 50% relative humidity, and then the substrate of the dicing sheet From the side, ultraviolet irradiation (illuminance: 230 mW / cm ² , light amount: 190 mJ / cm ² ) was performed from the dicing sheet side under a nitrogen atmosphere using an ultraviolet irradiation device (“RAD-2000m / 12” manufactured by Lintec). . For the dicing sheet after ultraviolet irradiation, the adhesive strength was measured in the same manner as the measurement of PKG adhesive strength (before irradiation), and the obtained adhesive strength was determined as PKG adhesive strength (after irradiation) (unit: mN / 25 mm). did.
These results are shown in Table 1.

[Test Example 3] <Bending test>
The dicing sheets of Examples and Comparative Examples were irradiated with ultraviolet rays under the conditions described in Test Example 2 from the dicing sheet side in a nitrogen atmosphere. About the dicing sheet after ultraviolet irradiation, the bending test of the dicing sheet was performed using a Gardner-type mandrel bending tester with a mandrel diameter of 2 mm based on ASTM-D522. The pressure-sensitive adhesive layer of the dicing sheet after the bending test was observed to confirm whether or not cracking occurred.
A similar test was conducted with a mandrel diameter of 1 mm. The pressure-sensitive adhesive layer of the dicing sheet after the bending test was observed to confirm whether or not cracking occurred.
These results are shown in Table 1.

Test Example 4 <Evaluation of Ease of Chip Scattering and Adhesive Aggregate>
A sealing resin of a semiconductor package (50 mm × 50 mm, thickness 600 μm, arithmetic average roughness Ra: 2 μm of a dicing sheet pasting surface) formed by molding a sealing resin composition (“KE-G1250” manufactured by Kyocera Chemical Co., Ltd.) The dicing sheets of Examples and Comparative Examples were attached to the surface using a tape mounter (“Adwill RAD2500” manufactured by Lintec) and fixed to a ring frame for dicing (“2-6-1” manufactured by Disco). Next, the semiconductor package was diced into 1 mm square semiconductor components under the following dicing conditions. After dicing, the number of semiconductor components scattered from the dicing sheet was counted visually. The ratio (%) of the number of scattered semiconductor components to the number of diced semiconductor components was calculated, and less than 10% was judged as “good” and 10% or more was judged as “bad”.
Moreover, generation | occurrence | production of the adhesive aggregate by dicing was confirmed with the microscope, and the magnitude | size of the adhesive aggregate in the chip | tip side surface was measured. The ease of occurrence of the pressure-sensitive adhesive aggregate was evaluated based on the presence or absence of the pressure-sensitive adhesive aggregate of 10 μm or more.
These results are shown in Table 1.

<Dicing conditions>
・ Dicing machine: “DFD-651” manufactured by DISCO
・ Blade: “ZBT-5074 (Z111OLS3)” manufactured by DISCO
・ Blade thickness: 0.17 mm
-Blade tip length: 3.3 mm
・ Blade rotation speed: 30000rpm
・ Cutting speed: 100 mm / min ・ Base material cutting depth: 50 μm
・ Cutting water volume: 1.0 L / min ・ Cutting water temperature: 20 ° C.

[Test Example 5] <Visibility of laser marking>
A sealing resin of a semiconductor package (50 mm × 50 mm, thickness 600 μm, arithmetic average roughness Ra: 2 μm of a dicing sheet pasting surface) formed by molding a sealing resin composition (“KE-G1250” manufactured by Kyocera Chemical Co., Ltd.) Laser marking was performed on the surface under the following conditions. When the dicing sheets of Examples and Comparative Examples are pasted on the surface of the sealing resin, and after the ultraviolet irradiation is performed under the conditions described in Test Example 2 immediately after the pasting (Condition 1), and from the pasting 23 Marking on the surface of the sealing resin of the semiconductor package in the case of peeling in the condition described in Test Example 2 after being stored in an environment of 50 ° C. and a relative humidity of 50% after being irradiated with ultraviolet rays (Condition 2) The part to which the mark was applied was visually observed to determine whether the visibility of the marking part was good or bad. The results are shown in Table 1.

<Laser marking conditions>
-"Panasonic" LP-V10U-w20
・ Laser used: FAYb Laser (wavelength: 1064 nm)
・ Scanning speed: 400mm / sec ・ Printing pulse cycle: 1000μs

  As can be seen from Table 1, in the dicing sheet of the example satisfying the conditions of the present invention, chip scattering was difficult to occur. Moreover, the dicing sheet of the example was excellent in bending resistance. Therefore, when the dicing sheet of the example was used, the visibility of the laser marking of the semiconductor package after peeling the dicing sheet was good.

  The dicing sheet according to the present invention is suitably used as a dicing sheet for semiconductor-related members such as a silicon wafer with a protective film and a semiconductor package, particularly a semiconductor-related member provided with a surface having a recess formed by laser marking or the like on the adherend surface. It is done.

DESCRIPTION OF SYMBOLS 1 ... Dicing sheet 2 ... Base material 3 ... Adhesive layer

Claims (7)

A dicing sheet comprising a base material and an adhesive layer laminated on at least one surface of the base material,
The pressure-sensitive adhesive layer is formed from a pressure-sensitive adhesive composition containing an energy polymerizable compound (B) that is a compound having an energy ray polymerizable functional group,
The pressure-sensitive adhesive layer has a storage elastic modulus of 135,000 Pa or less at 23 ° C. before irradiation with energy rays,
About the dicing sheet before irradiating the adhesive layer with energy rays, the adhesive strength measured when a 180 ° peel-off adhesive strength test is performed on a stainless steel test plate in accordance with JIS Z0237: 2009 is 10N. / 25mm or more,
After irradiating the adhesive layer of the dicing sheet with energy rays, the dicing sheet may be subjected to a bending test using a Gardner mandrel bending tester with a mandrel diameter of 2 mm based on ASTM-D522. The dicing sheet is characterized in that no crack occurs in the pressure-sensitive adhesive layer after irradiation with the energy beam.   2. The dicing sheet according to claim 1, wherein, in the bending test, even if the diameter of the mandrel is set to 1 mm, the pressure-sensitive adhesive layer after irradiation with the energy beam does not crack.   The dicing sheet according to claim 1 or 2 whose thickness of said adhesive layer is 25 micrometers or less. The pressure-sensitive adhesive composition further includes at least one of a main agent (A) and the energy polymerizable compound (B) including a compound (B _A ) having a function as the main agent (A). The dicing sheet according to any one of claims 1 to 3. The energy polymerizable compound (B) has a weight average molecular weight of 4,000 or less, and is selected from the group consisting of monofunctional monomers and polyfunctional monomers having energy beam polymerizable groups, and monofunctional and polyfunctional oligomers. Comprising one or more compounds having a storage elastic modulus adjusting function (B _D ),
Content of the said compound ( _BD ) in the said adhesive composition is 35 mass parts or more and 200 mass parts with respect to 100 mass parts of content of the substance which has a function as the said main ingredient (A) in the said adhesive composition. The dicing sheet according to claim 4, which is the following.   The pressure-sensitive adhesive composition comprises a storage modulus modifier (D) having a weight average molecular weight of 4,000 or less (monofunctional monomer and polyfunctional monomer having a weight average molecular weight of 4,000 or less and having an energy ray polymerizable group). And a compound consisting of one or more selected from the group consisting of monofunctional and polyfunctional oligomers).) The dicing sheet according to any one of claims 1 to 4. The surface of the adhesive layer side of the dicing sheet according to any one of claims 1 to 6 is affixed to a surface of a semiconductor-related member, and the semiconductor-related member on the dicing sheet is cut into pieces. A device chip manufacturing method for obtaining a plurality of chips,
The chip manufacturing method, wherein the surface of the semiconductor-related member to which the surface on the pressure-sensitive adhesive layer side of the dicing sheet is attached has a recess.

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