Method for manufacturing film-like adhesives, film-like adhesive composite sheets, and workpieces with film-like adhesives.

Abstract

The present invention provides a film-like adhesive for use in plasma dicing, which allows for a shorter time than conventional methods to reach a target vacuum level in a vacuum chamber containing the film-like adhesive, a composite sheet of the film-like adhesive, and a method for manufacturing a workpiece with the film-like adhesive. [Solution] A film-like adhesive for use in plasma dicing, wherein the weight loss rate (ΔW1) of the film-like adhesive when heated at 200°C for 1 hour is 10% or less.

Description

Technical Field

[0001] The present invention relates to a film adhesive, a film adhesive composite sheet, and a method for manufacturing a workpiece with a film adhesive.

Background Art

[0002] When manufacturing a semiconductor device, for example, a semiconductor chip with a film adhesive provided on the back surface (the surface opposite to the circuit surface) of the semiconductor chip is manufactured, and this is adhered and fixed to a circuit board by the film adhesive therein for mounting. The film adhesive usually has thermosetting properties and is cured by heating. After adhering the semiconductor chip with the film adhesive to the circuit board, the film adhesive is thermally cured to fix the semiconductor chip to the circuit board.

[0003] The semiconductor chip with the film adhesive can be manufactured, for example, by the following method. That is, first, a film adhesive composite sheet (for example, a die bonding sheet) including a support sheet and a film adhesive provided on one surface of the support sheet is used, and the film adhesive therein is attached to the back surface (the surface opposite to the circuit surface) of the semiconductor wafer. Next, on the support sheet, the semiconductor wafer is divided to produce semiconductor chips, and by cutting the film adhesive, a plurality of the semiconductor chips with the film adhesive are produced on the support sheet (see Patent Document 1, etc.).

[0004] In addition, the semiconductor chip with the film adhesive can also be manufactured by the following method. That is, first, a large number of parallel grooves are formed in two directions perpendicular to each other from the circuit surface to the back surface of the semiconductor wafer. At this time, the interval between adjacent grooves is adjusted so that semiconductor chips of a desired size can be obtained. Next, after forming the grooves, a backgrind tape is attached to the circuit surface of the semiconductor wafer, and then the back surface of the semiconductor wafer is ground. The back surface is ground until the grooves appear, or, before the grooves appear, the semiconductor wafer is divided at the groove formation sites by vibrations applied to the semiconductor wafer while the back surface is being ground, thereby producing a large number of aligned semiconductor chips. These semiconductor chips are held together by the backgrind tape.

[0005] Next, a film-like adhesive composite sheet (for example, a die bonding sheet) is used, which comprises a support sheet and a film-like adhesive provided on one surface of the support sheet. The film-like adhesive within the composite sheet is then attached to the back surface (in other words, the grinding surface) of the aforementioned number of semiconductor chips. Next, the backgrind tape is removed from these semiconductor chips. At this stage, these semiconductor chips are held in place by a film-like adhesive. Next, a laser beam is irradiated onto the portion of the film-like adhesive that is exposed between multiple semiconductor chips, cutting the film-like adhesive along the semiconductor chips. As a result, a number of semiconductor chips with film-like adhesive attached, each comprising a semiconductor chip and the cut film-like adhesive provided on the back surface of the semiconductor chip, are obtained on a support sheet.

[0006] These film-like adhesive semiconductor chips are pulled away from the support sheet and picked up, yielding the desired film-like adhesive semiconductor chip.

[0007] The above-mentioned splitting of semiconductor wafers and cutting of film-like adhesives can be carried out by various methods. For example, blade dicing, which uses a blade, is a widely known method for continuously splitting semiconductor wafers and cutting film-like adhesives, but plasma dicing, which uses plasma irradiation, is also known. In the case of plasma dicing, attempts have been made to plasma etch the film-like adhesive by supplying high-frequency power to a vacuum chamber while an etching process gas is supplied to the vacuum chamber, thereby generating plasma in the vacuum chamber (see Patent Documents 2, 3 and 4, Non-Patent Document 1, etc.). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Publication No. 2013-194103 [Patent Document 2] Japanese Patent Publication No. 2004-172364 [Patent Document 3] Japanese Patent Publication No. 2016-171262 [Patent Document 4] Japanese Patent Publication No. 2021-108339 [Non-patent literature]

[0009] [Non-Patent Document 1] Frank Wei,et. al., Plasma Dicing Fully Integrated Process-Flows Suitable for BEOL Advanced Packaging Fabrications, 2017 IEEE 67th Electronic Components and Technology Conference (ECTC), DOI:10.1109 / ECTC.2017.269 [Overview of the project] [Problems that the invention aims to solve]

[0010] However, when attempting to reduce the pressure inside a vacuum chamber containing a film-like adhesive for plasma dicing, there was a problem in that it took a long time to reach the target vacuum level inside the vacuum chamber due to the gas released from the film-like adhesive.

[0011] Up to this point, we have explained the problems encountered when manufacturing semiconductor chips with film-like adhesive from semiconductor wafers, using this as an example. However, similar problems can also arise when plasma dicing film-like adhesive to produce workpieces with film-like adhesive from wafers other than semiconductor wafers.

[0012] The present invention aims to provide a film-like adhesive for use in plasma dicing, which allows for a shorter time than conventional methods to reach a target vacuum level in a vacuum chamber containing the film-like adhesive, a film-like adhesive composite sheet, and a method for manufacturing a workpiece with the film-like adhesive. [Means for solving the problem]

[0013] To solve the above problems, the present invention employs the following configuration. [1] A film-like adhesive for use in plasma dicing, A film-like adhesive wherein the weight loss rate (ΔW1) when the film-like adhesive is heated at 200°C for 1 hour is 10% or less. [2] The film-like adhesive according to [1], wherein the film-like adhesive contains a filler (d), and the ratio of the content of the filler (d) to the total mass of the film-like adhesive is 2% by mass or more. [3] The film-like adhesive according to [1] or [2], wherein the film-like adhesive contains an epoxy resin (b1) which is solid at room temperature, and the ratio of the content of the epoxy resin (b1) which is solid at room temperature to the total mass of the epoxy resin (b1) is 50% by mass or more. [4] The film-like adhesive contains an epoxy resin (b1), and the ratio of the content of the epoxy resin (b1) to the total mass of the film-like adhesive is 30% by mass or more and 80% by mass or less. The film-like adhesive according to any one of [1] to [3]. [5] The film-like adhesive contains a binder resin (a), and the weight average molecular weight (Mw) of the binder resin (a) is more than 3000. The film-like adhesive according to any one of [1] to [4].

[0014] [6] A base material and a film-like adhesive provided on one surface of the base material. The film-like adhesive composite sheet, wherein the film-like adhesive is the film-like adhesive according to any one of [1] to [5].

[0015] [7] Using a workpiece group holder including a support sheet, a film-like adhesive provided on one surface of the support sheet, and a plurality of workpiece processed products aligned and held on the surface of the film-like adhesive opposite to the support sheet side, plasma is irradiated from the side of the plurality of workpiece processed products to the film-like adhesive exposed between the plurality of workpiece processed products in the workpiece group holder, the film-like adhesive is dry-etched, and the film-like adhesive is cut along the workpiece processed products, thereby producing a film-like adhesive workpiece group holder in which a plurality of workpiece processed products with film-like adhesives are aligned and held on one surface of the support sheet. The method for manufacturing a workpiece processed product with a film-like adhesive, wherein the film-like adhesive is the film-like adhesive according to any one of [1] to [5]. The film-like adhesive is the film-like adhesive according to any one of [1] to [5].

Effect of the Invention

[0016] The present invention provides a film-like adhesive for use in plasma dicing, which allows for a shorter time than conventional methods to reach a target vacuum level in a vacuum chamber containing the film-like adhesive, a film-like adhesive composite sheet, and a method for manufacturing a workpiece coated with the film-like adhesive. [Brief explanation of the drawing]

[0017] [Figure 1] This is a schematic cross-sectional view showing an example of a film-like adhesive composite sheet according to one embodiment of the present invention. [Figure 2A] This is a schematic cross-sectional view illustrating a part of the process in an example of a method for manufacturing a workpiece with a film-like adhesive according to one embodiment of the present invention. [Figure 2B] This is a schematic cross-sectional view illustrating a part of the process in an example of a method for manufacturing a workpiece with a film-like adhesive according to one embodiment of the present invention. [Figure 2C] This is a schematic cross-sectional view illustrating a part of the process in an example of a method for manufacturing a workpiece with a film-like adhesive according to one embodiment of the present invention. [Figure 2D] This is a schematic cross-sectional view illustrating a part of the process in an example of a method for manufacturing a workpiece with a film-like adhesive according to one embodiment of the present invention. [Modes for carrying out the invention]

[0018] ◇Film-type adhesive A film-like adhesive according to one embodiment of the present invention is a film-like adhesive for use in plasma dicing, wherein the weight loss rate (ΔW1) of the film-like adhesive when heated at 200°C for 1 hour is 10% or less. The film-like adhesive of this embodiment allows for a shorter time to reach the target vacuum level in the vacuum chamber containing the film-like adhesive compared to conventional methods. Therefore, the film-like adhesive can be cut quickly by plasma dicing. In order to reach the target vacuum level in the vacuum chamber more quickly, the weight loss rate (ΔW1) is 10% or less, more preferably 5% or less, and more preferably 4% or less.

[0019] When manufacturing a workpiece with a film-like adhesive by plasma dicing a film-like adhesive from a workpiece such as a semiconductor wafer that has a film-like adhesive, the cutting of the film-like adhesive by plasma irradiation proceeds by plasma etching.

[0020] The workpiece with the aforementioned film-like adhesive can be used in the manufacture of the circuit board device described later.

[0021] In this specification, "substrate device" means a device constructed by bonding a workpiece with a film-like adhesive to a circuit board using that film-like adhesive. For example, if a semiconductor wafer is used as the workpiece, a semiconductor device would be an example of a substrate device.

[0022] A film-like adhesive composite sheet, described later, can be constructed by directly laminating the film-like adhesive of this embodiment onto a substrate, or by using a dicing sheet, which is a laminate of a substrate and an adhesive layer, and laminating the film-like adhesive of this embodiment on the side of the adhesive layer opposite to the substrate. This film-like adhesive composite sheet can be used in the same way as known dicing die bonding sheets.

[0023] The film-like adhesive of this embodiment may or may not be curable (i.e., it may be non-curable). If the film-like adhesive is curable, it may or may not be energy-ray curable, and it may or may not be thermosetting, but it is preferable that it is thermosetting. When the film-like adhesive used for mounting workpieces with the film-like adhesive in a substrate device is thermosetting, the thermosetting product formed by thermosetting them after bonding has high impact resistance and maintains sufficient adhesive properties even under severe high temperature and high humidity conditions.

[0024] In this specification, "energy ray" means an electromagnetic wave or charged particle beam that has an energy quantum. Examples of energy rays include ultraviolet rays, radiation, electron beams, etc. Furthermore, "energy ray curability" refers to the property of hardening when irradiated with energy rays, while "non-energy ray curability" refers to the property of not hardening even when irradiated with energy rays. Furthermore, "thermosetting" refers to the property of hardening when heated. Furthermore, "non-curable" means that it does not harden regardless of whether it is heated or irradiated with energy rays.

[0025] When the cured product of the aforementioned film-like adhesive is actually used, the curing conditions for curing the film-like adhesive to form the cured product are not particularly limited, as long as the degree of curing of the cured product is sufficiently high, and can be appropriately selected according to the type of film-like adhesive. The heating temperature during the heat curing of the film-like adhesive is preferably 100 to 200°C. The heating time during the heat curing is preferably 0.5 to 5 hours.

[0026] The film-like adhesive of this embodiment is for plasma dicing, and is particularly suitable for plasma dicing the film-like adhesive using plasma generated from a process gas such as SF6 gas or oxygen (O2) gas. The components of the film-like adhesive in this embodiment will be described in detail later.

[0027] <Example of film-type adhesive> The film-like adhesive of this embodiment may, for example, have a first release film on one side (which may be referred to as the "first side" in this specification) and a second release film on the other side opposite to the first side (which may be referred to as the "second side" in this specification). Such a film-like adhesive is suitable for storage, for example, in roll form. The first release film and the second release film may both be known types. The first release film and the second release film may be the same, or they may be different, for example, requiring different peeling forces when peeling them from a film-like adhesive. It is preferable that both the first release film and the second release film are release films constructed by forming a silicone-based release agent layer on one side of a polyethylene terephthalate film (silicone treatment).

[0028] In the case of a film-type adhesive, both the first release film and the second release film are removed, and one of the resulting exposed surfaces becomes the surface to be attached to the workpiece or workpiece, while the other surface may be, for example, the surface to be attached to the support sheet described later.

[0029] The release film may be provided on only one side of the film-like adhesive, that is, only the first side or only the second side.

[0030] <Other components of film-type adhesives> The film-like adhesive may consist of one layer (single layer) or of two or more layers. If the film-like adhesive consists of multiple layers, these layers may be identical or different from each other, and there are no particular limitations on the combination of these layers.

[0031] In this specification, not only in the case of film-like adhesives, "multiple layers may be identical or different from one another" means "all layers may be identical, all layers may be different, or only some layers may be identical," and further, "multiple layers are different from one another" means "at least one of the constituent materials and thickness of each layer is different from the other."

[0032] The thickness of the film-like adhesive is preferably 1 to 70 μm, more preferably 2 to 50 μm, and particularly preferably 3 to 30 μm. When the thickness of the film-like adhesive is above the lower limit, the strength of the film-like adhesive is increased, and the effects obtained by using the film-like adhesive are also increased. When the thickness of the film-like adhesive is below the upper limit, excessive thickness of the film-like adhesive is avoided. Here, "thickness of the film adhesive" refers to the total thickness of the film adhesive. For example, the thickness of a multi-layered film adhesive refers to the total thickness of all the layers that make up the film adhesive.

[0033] In this specification, unless otherwise specified, "thickness" refers to the average of the thicknesses measured at five randomly selected locations on the object, and can be obtained using a constant-pressure thickness measuring instrument in accordance with JIS K7130.

[0034] <<Composition of film-like adhesives and adhesive compositions>> The aforementioned film-like adhesive can be formed using an adhesive composition containing its constituent materials. For example, the adhesive composition can be applied to the surface to which the film-like adhesive is to be formed using a known method, and dried as necessary, thereby forming the film-like adhesive in the desired area. The ratio of components that do not vaporize at room temperature in an adhesive composition is usually the same as the ratio of those components in a film-type adhesive.

[0035] In this specification, "room temperature" means a temperature that is neither cooled nor heated, i.e., a normal temperature, such as 18-28°C.

[0036] In a film-type adhesive, the ratio of the total content of one or more of the following components in the film-type adhesive to the total mass of the film-type adhesive shall not exceed 100% by mass. Similarly, in an adhesive composition, the ratio of the total content of one or more of the following components of the adhesive composition to the total mass of the adhesive composition shall not exceed 100% by mass.

[0037] The drying conditions for the adhesive composition are not particularly limited, but if the adhesive composition contains a solvent as described later, it is preferable to heat dry it. For example, adhesive compositions containing a solvent are preferably dried at 70 to 130°C for 10 seconds to 5 minutes. The components of the film-type adhesive and adhesive composition will be described in detail below.

[0038] Examples of the adhesive composition include a composition containing a binder resin (a) (which may be abbreviated as "composition (III)" in this specification), and it is preferable that the adhesive composition further contains an epoxy resin (b1) and a filler (d). An adhesive composition for forming a thermosetting film-like adhesive preferably contains a binder resin (a) and a thermosetting component (b), more preferably contains a binder resin (a), a thermosetting component (b), and a filler (d), and even more preferably contains a binder resin (a), a thermosetting component (b), a curing accelerator (c), and a filler (d).

[0039] The binder resin (a), thermosetting component (b), curing accelerator (c), and filler (d) contained in composition (III) and the film-like adhesive may each consist of only one type, or may contain only one type of binder resin (a), thermosetting component (b), curing accelerator (c), and filler (d), or may contain two or more types, and if there are two or more types, the combination and ratio thereof can be arbitrarily selected.

[0040] The composition (III) and the film-like adhesive preferably contain a binder resin (a), and the weight-average molecular weight (Mw) of the binder resin (a) is more than 3000. The weight-average molecular weight (Mw) of the binder resin (a) being more than 3000 provides excellent film-forming properties for the film-like adhesive. Examples of binder resins (a) include acrylic resin (a1), polyester resin (a2), phenoxy resin, and polyaryl resin.

[0041] <Acrylic resin (a1)> The acrylic resin (a1) has constituent units derived from alkyl (meth)acrylate. Acrylic resin (a1) is a polymer compound that imparts film-forming properties and flexibility to film-like adhesives, and is also a component that increases the cutting speed when cutting film-like adhesives using plasma generated from process gases such as SF6 gas or oxygen (O2) gas.

[0042] In this specification, "(meth)acrylic acid" is a concept that encompasses both "acrylic acid" and "methacrylic acid." This also applies to terms similar to (meth)acrylic acid, such as (meth)acryloyl group.

[0043] The alkyl group constituting the alkyl ester may be linear, branched, or cyclic, and may have both a linear structure (either linear or branched, or both) and a cyclic structure. The cyclic alkyl group may be monocyclic or polycyclic.

[0044] The linear alkyl group preferably has 1 to 11 carbon atoms, and may be, for example, 1 to 8 or 1 to 5 carbon atoms. The branched alkyl group preferably has 3 to 11 carbon atoms, and may be, for example, 3 to 8 or 3 to 5 carbon atoms. The number of carbon atoms in the cyclic alkyl group is preferably 3 to 11, and may be, for example, 6 to 11 and 9 to 11.

[0045] Examples of alkyl (meth)acrylate (a11) esters (a11) in which the alkyl group has 1 to 11 carbon atoms include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, n-pentyl (meth)acrylate, isopentyl (meth)acrylate, neopentyl (meth)acrylate, tert-pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, and undecyl (meth)acrylate.

[0046] Examples of alkyl (meth)acrylate esters in which the alkyl group is cyclic include isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate.

[0047] The number of branches in the branched alkyl hydrocarbon chain (sometimes simply referred to as "number of alkyl group branches" in this specification) may be 1 or more, and more preferably 2 or more. The greater the number of branches, the faster the cutting speed of the film-like adhesive during plasma dicing tends to be. On the other hand, in terms of making the (meth)acrylate alkyl ester easier to manufacture or obtain, it is preferable that the number of branches of the alkyl group is 3 or less. For example, the isobutyl group has 1 branching, and the tert-butyl group has 2 branching.

[0048] In terms of increasing the cutting speed during plasma dicing of the film-like adhesive, the alkyl group is preferably linear or branched, and more preferably branched.

[0049] The monomers that make up the acrylic resin (a1) may be just one type or two or more types, and if there are two or more types, their combination and ratio can be arbitrarily selected.

[0050] The acrylic resin (a1) may or may not have constituent units derived from monomers other than the alkyl (meth)acrylate (a11). Examples of monomers other than the (meth)acrylate alkyl ester (a11) mentioned above include (meth)acrylate hydroxyalkyl esters such as hydroxymethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate; (meth)acrylate alkyl esters in which the alkyl group constituting the alkyl ester has 12 or more carbon atoms; (meth)acrylic acid; glycidyl (meth)acrylate having an epoxy group; itaconic acid; vinyl acetate; acrylonitrile, styrene, N-methylolacrylamide, etc.

[0051] The hydroxyalkyl (meth)acrylate ester is preferably one in which the hydroxyalkyl group is linear (linear or branched), preferably one in which the hydroxyalkyl group has 1 to 11 carbon atoms, and more preferably one in which the hydroxyalkyl group is linear and has 1 to 11 carbon atoms. Examples of hydroxyalkyl groups having 1 to 11 carbon atoms include groups that constitute the alkyl ester in the alkyl (meth)acrylate (a11) and have a structure in which one hydrogen atom is substituted with a hydroxyl group, in the alkyl group having 11 or fewer carbon atoms.

[0052] The acrylic resin (a1) preferably has a constituent unit derived from an alkyl (meth)acrylate (a11) and a constituent unit derived from a hydroxyalkyl (meth)acrylate.

[0053] The glass transition temperature (Tg) of the acrylic resin (a1) is preferably -60 to 70°C, more preferably -55 to 40°C, and may be any of -30 to 40°C or -55 to 15°C. When the Tg of the acrylic resin is above the lower limit, the adhesive strength between the film-like adhesive and the adherend is suppressed, making it easier to pick up the workpiece with the film-like adhesive from the substrate or dicing sheet described later. When the Tg of the acrylic resin is below the upper limit, the adhesive strength between the film-like adhesive and the workpiece is improved.

[0054] If the acrylic resin (a1) has two or more constituent units, the glass transition temperature (Tg) of the acrylic resin (a1) can be calculated using Fox's formula. The Tg of the homopolymer of the monomers that derive the constituent units can be the value specified in the Polymer Data Handbook, Adhesion Handbook, or Polymer Handbook.

[0055] The weight-average molecular weight (Mw) of the acrylic resin (a1) is preferably greater than 3000, more preferably 100,000 or more, and even more preferably 200,000 or more. For example, it may be 300,000 or more, or 400,000 or more. The larger the weight-average molecular weight of the acrylic resin (a1), the better the film-forming properties of the film-like adhesive tend to be, and the faster the cutting speed of the film-like adhesive during plasma dicing tends to be.

[0056] The upper limit of the weight-average molecular weight of the acrylic resin (a1) is not particularly limited. For example, in terms of ensuring high uniformity of dispersion of the acrylic resin (a1) in composition (III) and the film-like adhesive, the weight-average molecular weight of the acrylic resin (a1) is preferably less than 1,500,000, and may be, for example, 1,300,000 or less, or 1,000,000 or less.

[0057] Furthermore, as the weight-average molecular weight of the acrylic resin (a1) increases within the above numerical range, the dimensional stability (stability over time during storage) of the film-like adhesive improves, and as it decreases, the film-like adhesive becomes more easily conformable to the uneven surface of the adherend.

[0058] In this specification, not only in the case of acrylic resin (a1), but unless otherwise specified, "weight-average molecular weight" refers to the polystyrene equivalent value measured by gel permeation chromatography (GPC).

[0059] In the film-like adhesive, the ratio of the acrylic resin (a1) content to the total mass of the film-like adhesive is preferably 10 to 40% by mass, and may be, for example, 10 to 30% by mass or 15 to 20% by mass. When the ratio is above the lower limit, the film-forming properties and flexibility of the film-like adhesive, as well as the cutting speed of the film-like adhesive during plasma dicing, are both improved. When the ratio is below the upper limit, excessive use of acrylic resin (a1) is suppressed.

[0060] The above-mentioned statement regarding the ratio of the acrylic resin (a1) content to the total mass of the film-like adhesive is equivalent to saying that in composition (III), the ratio of the acrylic resin (a1) content to the total content of all components other than the solvent is preferably 10 to 40% by mass, and may be, for example, 10 to 30% by mass and 15 to 20% by mass. This is based on the fact that, in the process of removing the solvent from a solvent-containing resin composition to form a resin film, the amount of components other than the solvent usually does not change, and the ratio of the contents of non-solvent components is the same in the resin composition and the resin film. Therefore, in this specification, not limited to the case of film-like adhesives, the content of non-solvent components will mainly refer to the content in the resin film obtained by removing the solvent from the resin composition.

[0061] <Polyester resin (a2)> The polyester resin (a2) is obtained by copolymerizing a copolymer component containing a polycarboxylic acid component (A1) and a polyol component (A2).

[0062] [Polyhydric carboxylic acid components] Examples of the polycarboxylic acid component (A1) used in this disclosure include: Aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, benzylmalonic acid, diphenic acid, 4,4'-oxydibenzoic acid, and naphthalenedicarboxylic acid; Aliphatic dicarboxylic acids such as malonic acid, dimethylmalonic acid, succinic acid, glutaric acid, adipic acid, trimethyladipic acid, pimelic acid, 2,2-dimethylglutaric acid, azelaic acid, sebacic acid, fumaric acid, maleic acid, itaconic acid, thiodipropionic acid, and diglycolic acid; Alicyclic dicarboxylic acids such as 1,3-cyclopentanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclopentanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 2,5-norbornanedicarboxylic acid, and adamantanedicarboxylic acid; Examples of divalent carboxylic acids include the following. These can be used individually or in combination of two or more.

[0063] [Polyol component (A2)] Examples of the polyol component (A2) used in this disclosure include: Aliphatic diols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 2,4-dimethyl-2-ethylhexane-1,3-diol, 2-methyl-1,3-propanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2-ethyl-2-butyl-1,3-propanediol, 2-ethyl-2-isobutyl-1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 2,2,4-trimethyl-1,6-hexanediol; Alicyclic diols such as 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, spiroglycol, tricyclodecanedimethanol, adamantanediol, and 2,2,4,4-tetramethyl-1,3-cyclobutanediol; Aromatic diols such as 4,4'-thiodiphenol, 4,4'-methylenediphenol, 4,4'-dihydroxybiphenyl, o-, m- and p-dihydroxybenzene, 2,5-naphthalenediol, p-xylenediol, and their ethylene oxide and propylene oxide adducts; Examples of dihydric alcohols include the following. These can be used individually or in combination of two or more.

[0064] Among these, aliphatic diols and alicyclic diols are preferred due to their excellent reactivity, and particularly preferred are ethylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, neopentyl glycol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol as aliphatic diols, and 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, and 1,4-cyclohexanedimethanol as alicyclic diols.

[0065] As the binder resin (a) used in composition (III) and the film-like adhesive, the polyester resin (a2) is preferably an amorphous polyester resin.

[0066] Amorphous polyester resin is produced by arbitrarily selecting the above-mentioned polycarboxylic acid component (A1) and polyol component (A2) and carrying out a polycondensation reaction of these in the presence of a catalyst using a known method. It is preferable to use three or more types of polycarboxylic acid component (A1) and polyol component (B1) as copolymer components of the amorphous polyester resin. That is, the amorphous polyester resin is preferably a copolymer containing two or more types of polycarboxylic acid component (A1) or two or more types of polyol component (B1), or both.

[0067] The number-average molecular weight of amorphous polyester resin is preferably 500 to 100,000, particularly preferably 1,000 to 80,000, and even more preferably 1,500 to 50,000, from the viewpoint of cohesive force and mechanical strength.

[0068] The number-average molecular weight mentioned above is calculated based on the molecular weight of standard polystyrene and is measured using high-performance liquid chromatography (HLC-8220GPC, manufactured by Tosoh Corporation) with two TSKgelGMHXL columns in series.

[0069] The amorphous polyester resin used as the binder resin (a) may be a commercially available product, for example, the amorphous solvent-soluble Nichigo Polyester® TP-220 (Tg: 70℃), TP-219 (Tg: 40℃), LP-011 (Tg: 4℃), LP-022 (Tg: -15℃) manufactured by Mitsubishi Chemical Corporation, and the Byron® 220 (Tg: 53℃), GK-360 (Tg: 56℃), 600 (Tg: 47℃), GK-810 (Tg: 46℃), 630 (Tg: 7℃), GK-680 (Tg: 10℃) manufactured by Toyobo MC Co., Ltd.

[0070] <Other binder resins (a)> Other binder resins (a) not included in acrylic resin (a1) and polyester resin (a2) include, for example, urethane resin; phenoxy resin; silicone resin, etc.

[0071] <Thermosetting component (b)> Thermosetting component (b) is a component that has thermosetting properties and is used to heat-cur the film-like adhesive. Examples of the thermosetting component (b) include epoxy-based thermosetting resins, thermosetting polyimide resins, and unsaturated polyester resins, with epoxy-based thermosetting resins being preferred.

[0072] In this specification, thermosetting polyimide resin is a general term encompassing a polyimide precursor and a thermosetting polyimide, both of which form a polyimide resin through thermosetting.

[0073] [Epoxy thermosetting resin] The epoxy-based thermosetting resin comprises an epoxy resin (b1) and a thermosetting agent (b2). The epoxy resin (b1) and thermosetting agent (b2) contained in composition (III) and the film-like adhesive may each consist of only one type or two or more types, and if there are two or more types, their combination and ratio can be arbitrarily selected.

[0074] (Epoxy resin (b1)) Examples of epoxy resins (b1) include well-known ones, such as polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydrogenated products, orthocresol novolac type epoxy resins, dicyclopentadiene type epoxy resins, biphenyl type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, phenylene skeleton type epoxy resins, and other bifunctional or more epoxy compounds.

[0075] The number-average molecular weight of the epoxy resin (b1) is not particularly limited, but is preferably 300 to 30000 from the viewpoint of the curability of the film-like adhesive and the strength and heat resistance of the cured product of the film-like adhesive. The epoxy equivalent of epoxy resin (b1) is preferably 100 to 1000 g / eq, and may be, for example, 100 to 600 g / eq and 150 to 300 g / eq.

[0076] The epoxy resin (b1) contained in composition (III) and the film-like adhesive may be one type or two or more types, and if there are two or more types, their combination and ratio can be arbitrarily selected.

[0077] The composition (III) and the film-like adhesive contain an epoxy resin (b1) which includes an epoxy resin (b1-1) that is solid at room temperature, and it is preferable that the ratio of the content of the epoxy resin (b1-1) which is solid at room temperature to the total mass of the epoxy resin (b1) is 50% by mass or more. The composition (III) and the film-like adhesive also preferably contain an epoxy resin (b1-2) which is liquid at room temperature to the total mass of the epoxy resin (b1) is 50% by mass or less. By having a content of epoxy resin (b1-1) which is solid at room temperature, which is 50% by mass or more, the time required to reach the target vacuum level in the vacuum chamber containing the film-like adhesive can be shortened, and the film-like adhesive can be cut quickly by plasma dicing.

[0078] The composition (III) and the film-like adhesive preferably contain a dicyclopentadiene type epoxy resin or a bisphenol F type epoxy resin as the epoxy resin (b1). The inclusion of such a combination of epoxy resins (b1) in the film-like adhesive improves the pickability of the workpiece with the film-like adhesive or the workpiece with the cured adhesive.

[0079] In this specification, the characteristic of being able to properly pick up an object, such as a workpiece with a film-like adhesive attached, from a base material or dicing sheet is sometimes referred to as "pickup capability."

[0080] The composition (III) and the film-like adhesive preferably contain epoxy resin (b1), and more preferably the ratio of the epoxy resin (b1) content to the total mass of the film-like adhesive is 30% by mass or more and 80% by mass or less, and even more preferably 50% by mass or more and 80% by mass or less.

[0081] When composition (III) and the film-like adhesive contain a dicyclopentadiene type epoxy resin or a bisphenol F type epoxy resin, the ratio of the total content of the dicyclopentadiene type epoxy resin and the bisphenol F type epoxy resin to the content of epoxy resin (b1) in composition (III) and the film-like adhesive is preferably 50% by mass or more, more preferably 55% by mass or more, and even more preferably 60% by mass or more. When the ratio is above the lower limit, the effects obtained by the film-like adhesive containing the dicyclopentadiene type epoxy resin and the bisphenol F type epoxy resin are significantly enhanced. On the other hand, the aforementioned ratio is 100% by mass or less.

[0082] (Thermosetting agent (b2)) The thermosetting agent (b2) is a curing agent for epoxy resin (b1). Examples of the thermosetting agent (b2) include compounds having two or more functional groups capable of reacting with epoxy groups in one molecule. Examples of the functional groups include phenolic hydroxyl groups, alcoholic hydroxyl groups, amino groups, carboxyl groups, and groups in which an acid group has been converted to an anhydride. It is preferable that the functional group is a phenolic hydroxyl group, an amino group, or a group in which an acid group has been converted to an anhydride, and more preferably a phenolic hydroxyl group or an amino group.

[0083] Examples of thermosetting agents (b2) that include phenolic curing agents having phenolic hydroxyl groups include polyfunctional phenolic resins, biphenols, novolac-type phenolic resins, dicyclopentadiene-type phenolic resins, and aralkyl-type phenolic resins. Examples of amine-based curing agents containing an amino group among the thermosetting agents (b2) include dicyandiamide (DICY).

[0084] The hydroxyl group equivalent of the thermosetting agent (b2) is preferably 10 to 120 g / eq, and may be, for example, 10 to 60 g / eq and 10 to 40 g / eq.

[0085] Among the thermosetting agents (b2), the number average molecular weight of the resin components, such as polyfunctional phenolic resins, novolac-type phenolic resins, dicyclopentadiene-type phenolic resins, and aralkyl-type phenolic resins, is preferably 300 to 30,000, more preferably 400 to 10,000, and particularly preferably 500 to 3,000. The molecular weight of the non-resin component of the thermosetting agent (b2), such as biphenol or dicyandiamide, is not particularly limited, but is preferably 60 to 500.

[0086] When using a thermosetting component (b), the content of the thermosetting agent (b2) in composition (III) and the film-like adhesive is preferably 0.5 to 10 parts by mass per 100 parts by mass of epoxy resin (b1), for example, it may be 0.5 to 5 parts by mass or 0.5 to 3 parts by mass. When the content of the thermosetting agent (b2) is above the lower limit, the thermosetting of the film-like adhesive proceeds more easily. When the content of the thermosetting agent (b2) is below the upper limit, the moisture absorption rate of the film-like adhesive is reduced, and the reliability of the package obtained using the film-like adhesive is further improved.

[0087] When using a thermosetting component (b), the content of the thermosetting component (b) in composition (III) and the film adhesive (for example, the total content of epoxy resin (b1) and thermosetting agent (b2)) is preferably 50 to 800 parts by mass, more preferably 100 to 600 parts by mass, per 100 parts by mass of acrylic resin (a1). For example, it may be any of 100 to 500 parts by mass and 100 to 400 parts by mass, or any of 200 to 600 parts by mass and 300 to 600 parts by mass, or 200 to 500 parts by mass. Having the content of the thermosetting component (b) within this range makes it easier to adjust the adhesive strength between the film adhesive and the substrate or dicing sheet described later.

[0088] <Curing accelerator (c)> The curing accelerator (c) is an ingredient used to adjust the thermal curing rate of the film-type adhesive. Preferred curing accelerators (c) include, for example, imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, and 2-phenyl-4-methyl-5-hydroxymethylimidazole (imidazoles in which one or more hydrogen atoms are substituted with groups other than hydrogen atoms); tertiary amines; organophosphines (phosphines in which one or more hydrogen atoms are substituted with organic groups); tetraphenylborone salts; and inclusion compounds using the aforementioned imidazoles as guest compounds.

[0089] When a curing accelerator (c) is used, the content of the curing accelerator (c) in composition (III) and the film adhesive is preferably 0.01 to 5 parts by mass, and more preferably 0.1 to 3 parts by mass, per 100 parts by mass of the content of the thermosetting component (b) (for example, the total content of epoxy resin (b1) and thermosetting agent (b2)). When the content of the curing accelerator (c) is above the lower limit, the effect of using the curing accelerator (c) is more pronounced. When the content of the curing accelerator (c) is below the upper limit, for example, the effect of suppressing the migration and segregation of a highly polar curing accelerator (c) to the adhesive interface side with the adherend in the film adhesive under high temperature and high humidity conditions is enhanced, and the reliability of the package obtained using the film adhesive is further improved.

[0090] <Filling material (d)> By using a film-like adhesive containing filler (d), the time required to reach the target vacuum level in the vacuum chamber containing the film-like adhesive can be shortened compared to conventional methods, and the film-like adhesive can be quickly cut by plasma dicing.

[0091] The average particle size of the filler (d) is not particularly limited, but is preferably 10 nm to 5 μm. In this specification, "average particle diameter" refers to the particle diameter at 50% of the integrated value in the particle size distribution curve obtained by laser diffraction scattering (D 50 This refers to the value of ).

[0092] The filler (d) may be either an organic filler or an inorganic filler, but an inorganic filler is preferred. Preferred inorganic fillers include, for example, powders such as silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, and boron nitride; beads formed from these inorganic fillers in a spherical shape; surface-modified products of these inorganic fillers; single-crystal fibers of these inorganic fillers; and glass fibers. Among these, the inorganic filler is preferably silica, alumina, or a surface-modified version thereof.

[0093] In the film-like adhesive, the ratio of the filler (d) content to the total mass of the film-like adhesive is 0% by mass or more, preferably 2.0% by mass or more, more preferably 2.5% by mass or more, while preferably 20% by mass or less, and may be 15% by mass or less, or 10% by mass or less. The higher the ratio, the shorter the time required to reach the target vacuum level in the vacuum chamber containing the film-like adhesive. The lower the ratio, the better the coated surface condition of the film-like adhesive can be, and the cutting speed during plasma dicing of the film-like adhesive tends to be faster. The statement that a film-like adhesive substantially does not contain filler (d) means that the proportion is 0% by mass, or that filler (d) is not intentionally blended during the manufacture of the adhesive composition, and even if filler (d) is mixed into the adhesive composition and the film-like adhesive, the amount of mixing (the content of filler (d) in the adhesive composition and the film-like adhesive) is trace.

[0094] Composition (III) and the film-like adhesive may further contain, if necessary, other components that do not fall under any of the following categories: binder resin (a), thermosetting component (b), curing accelerator (c), and filler (d), in order to improve the various physical properties of the film-like adhesive. Other components contained in composition (III) and the film-like adhesive include, for example, coupling agents (e), crosslinking agents (f), energy ray-curable resins (g), photopolymerization initiators (h), colorants (i), and general-purpose additives (j). The other components contained in composition (III) and the film-like adhesive, such as the coupling agent (e), crosslinking agent (f), energy ray curable resin (g), photopolymerization initiator (h), colorant (i), and general-purpose additive (j), may be one type or two or more types, and if there are two or more types, their combination and ratio can be arbitrarily selected.

[0095] <Coupling agent (e)> The film-type adhesive exhibits improved adhesion and bonding to the substrate by containing a coupling agent (e). Furthermore, the inclusion of a coupling agent (e) in the film-type adhesive improves the water resistance of the cured product without compromising its heat resistance. The coupling agent (e) has a functional group that can react with inorganic or organic compounds.

[0096] When a coupling agent (e) is used, the content of the coupling agent (e) in composition (III) and the film adhesive is preferably 0.03 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, and may be, for example, 0.1 to 1 part by mass, based on 100 parts by mass of the total content of the acrylic resin (a1) and the thermosetting component (b). When the content of the coupling agent (e) is above the lower limit, the effects of using the coupling agent (e) are more pronounced, such as improved dispersibility of the filler (d) in the resin and improved adhesion of the film adhesive to the adherend.

[0097] <Crosslinking agent (f)> The crosslinking agent (f) crosslinks functional groups such as (meth)acryloyl groups and hydroxyl groups in the acrylic resin (a1) with other compounds. In this case, the initial adhesive strength and cohesive strength of the film-like adhesive can be adjusted.

[0098] Examples of crosslinking agents (f) include organic polyvalent isocyanate compounds, organic polyvalent imine compounds, metal chelate crosslinking agents (crosslinking agents having a metal chelate structure), and aziridine crosslinking agents (crosslinking agents having an aziridinyl group).

[0099] In composition (III) and the film-like adhesive, the content of the crosslinking agent (f) is preferably 6 parts by mass or less, and more preferably 3 parts by mass or less, per 100 parts by mass of the acrylic resin (a1). On the other hand, the content is 0 parts by mass or more. Since the pickability of workpieces with film-like adhesive tends to increase as the amount of crosslinking agent (f) decreases, it is particularly preferable that the amount is 0 parts by mass, that is, that the film-like adhesive does not contain crosslinking agent (f).

[0100] <Energy ray curing component (g)> The energy-ray curable component (g) is an energy-ray curable nonpolymer, or an energy-ray curable oligomer or polymer (polymer) that can be considered to have been synthesized from an energy-ray curable nonpolymer.

[0101] The aforementioned energy-ray curable nonpolymer cannot be considered a monomer polymer and is a component that possesses energy-ray curability. Examples of the energy-ray curable nonpolymer include compounds having at least one polymerizable double bond in the molecule, and acrylate compounds having a (meth)acryloyl group are preferred.

[0102] In a film-like adhesive, the ratio of the energy-ray curable component (g) to the total mass of the film-like adhesive is preferably 4% by mass or more, more preferably 6% by mass or more, and may be, for example, 7% by mass or more. When the ratio is above the lower limit, the energy-ray curing of the film-like adhesive becomes easier. On the other hand, the aforementioned ratio is preferably 20% by mass or less, in that it suppresses the excessive use of the energy ray curable component (g).

[0103] <Photopolymerization initiator (h)> Composition (III) and the film-like adhesive may contain a photopolymerization initiator (h).

[0104] Examples of the photopolymerization initiator (h) include benzoin compounds, acetophenone compounds, acylphosphine oxide compounds, sulfide compounds, α-ketol compounds, azo compounds, titanocene compounds, thioxanthone compounds, peroxide compounds, diketone compounds, quinone compounds, and the like. Furthermore, examples of photopolymerization initiators (h) include photosensitizers such as amines.

[0105] When a photopolymerization initiator (h) is used, the content of the photopolymerization initiator (h) in composition (III) and the film adhesive is preferably 0.1 to 12 parts by mass, more preferably 0.5 to 9 parts by mass, and even more preferably 1 to 6 parts by mass, based on the content of 100 parts by mass of the energy ray curable component (g).

[0106] <Coloring agent (i)> The coloring agent (i) is a component in the film-like adhesive and its cured product that can adjust the transmittance of light of various wavelengths. Examples of colorants (i) include known ones such as inorganic pigments, organic pigments, and organic dyes.

[0107] When a coloring agent (i) is used, the ratio of the coloring agent (i) content to the total mass of the film adhesive is preferably 0.01 to 10% by mass, regardless of the type of coloring agent (i). When the ratio is above the lower limit, the effect of using the coloring agent (i) is more pronounced. When the ratio is below the upper limit, excessive use of the coloring agent (i) is suppressed.

[0108] <General-purpose additive (j)> The general-purpose additive (j) may be any known additive and can be arbitrarily selected depending on the purpose; it is not particularly limited. Preferred general-purpose additives (j) include, for example, plasticizers, antistatic agents, antioxidants, gettering agents, defoaming agents, leveling agents, and the like. Examples of preferred general-purpose additives (j) contained in composition (III) and the film-like adhesive include antioxidants (j1).

[0109] When composition (III) and the film-like adhesive contain an antioxidant (j1), the ratio of the antioxidant (j1) content to the total mass of the film-like adhesive is preferably 0.1 to 5% by mass, and may be, for example, 0.5 to 3.5% by mass. When the ratio is above the lower limit, the pickability of the workpiece coated with the film-like adhesive is further improved. When the ratio is below the upper limit, excessive use of the antioxidant (j1) is suppressed.

[0110] If composition (III) and the film adhesive contain a general-purpose additive (i) other than the antioxidant (j1), the ratio of the content of the general-purpose additive (i) other than the antioxidant (j1) to the total mass of the film adhesive may be, for example, 0.1 to 10% by mass.

[0111] <Solvent> Composition (III) preferably further contains a solvent. Composition (III) containing a solvent has good handling properties. In this specification, unless otherwise specified, the term "solvent" includes not only substances that dissolve the target component but also dispersion media that disperse the target component.

[0112] The solvent is not particularly limited, but preferred examples include hydrocarbons such as toluene; alcohols such as methanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; and amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone. The solvent contained in composition (III) may be one type or two or more types, and if there are two or more types, their combination and ratio can be arbitrarily selected.

[0113] The solvent content of composition (III) is not particularly limited and may be appropriately selected depending on the type of components other than the solvent.

[0114] <<Method for manufacturing adhesive composition>> An adhesive composition (for example, composition (III)) is obtained by blending the components that constitute it. The temperature and time during the addition and mixing of each component are not particularly limited as long as the components do not deteriorate, and can be adjusted as appropriate, but a temperature of 15 to 30°C is preferred.

[0115] ◇Film-type adhesive composite sheet A film-like adhesive composite sheet according to one embodiment of the present invention comprises a base material and a film-like adhesive provided on one surface of the base material, wherein the film-like adhesive is the film-like adhesive according to the above-described embodiment of the present invention. A film-like adhesive composite sheet according to another embodiment of the present invention comprises a dicing sheet and a film-like adhesive provided on one surface of the dicing sheet, wherein the dicing sheet comprises a substrate and an adhesive layer provided on one surface of the substrate, the adhesive layer is disposed between the substrate and the film-like adhesive, and the film-like adhesive is the film-like adhesive according to the above-described embodiment. The film-like adhesive composite sheet of this embodiment can be used, for example, as a sheet for cutting a film-like adhesive that has been attached to a wafer by plasma irradiation. In either case, ultimately, as will be described later, the workpiece with the film-like adhesive obtained after plasma irradiation is separated from the substrate or dicing sheet and picked up.

[0116] The film-like adhesive composite sheet of this embodiment may be the same as a conventional film-like adhesive composite sheet, except that it comprises the film-like adhesive of this embodiment described above.

[0117] Each layer constituting the film-like adhesive composite sheet, such as the base material, adhesive layer, and film-like adhesive, may consist of one layer (single layer) or two or more layers. If it consists of multiple layers, these layers may be identical or different, and the combination of these layers is not particularly limited.

[0118] A film-like adhesive composite sheet, comprising a base material and a film-like adhesive, but without an adhesive layer, can have a lower overall content of low-molecular-weight components than a film-like adhesive composite sheet with a dicing sheet. When using such a film-like adhesive composite sheet without an adhesive layer, the volatilization of the contained components is suppressed when the vacuum chamber of the plasma irradiation device is evacuated for plasma dicing, allowing the desired vacuum level to be achieved in a short time. Furthermore, contamination due to the adhesion of volatile components within the plasma irradiation device can also be suppressed.

[0119] Figure 1 is a schematic cross-sectional view showing an example of a film-like adhesive composite sheet according to this embodiment. The film-like adhesive composite sheet 101 shown in Figure 1 comprises a support sheet 10 and a film-like adhesive 13 provided on one surface (sometimes referred to as the "first surface" in this specification) 10a of the support sheet 10.

[0120] The support sheet 10 consists only of the base material 11, and one side (first side) 10a of the support sheet 10 is the same as one side 11a of the base material 11. The other side (the side opposite to the film-like adhesive 13) 10b of the support sheet 10 is the same as the other side 11b of the base material 11.

[0121] In the film-like adhesive composite sheet 101, a jig adhesive layer 16 is provided in the region near the peripheral edge of the film-like adhesive 13 (a region with an annular planar shape along the peripheral edge) of the first surface 13a of the film-like adhesive 13 that is opposite to the support sheet 10 side.

[0122] The film-like adhesive composite sheet 101 further includes a release film 15 in the area of ​​the first surface 13a of the film-like adhesive 13 where the jig adhesive layer 16 is not provided. The release film 15 is further provided on the jig adhesive layer 16 in the area near the peripheral edge of the film-like adhesive 13. In the film-like adhesive composite sheet 101, the release film 15 has any configuration.

[0123] The film-like adhesive composite sheet 101 is used by attaching a workpiece or workpiece compound to the first surface 13a of the film-like adhesive 13 after the release film 15 has been removed. The side of the jig adhesive layer 16 opposite to the film-like adhesive 13 is attached to the fixing jig.

[0124] The film-like adhesive composite sheet of this embodiment is not limited to that shown in Figure 1, and for example, some components of this film-like adhesive composite sheet may be modified, deleted, or added without departing from the spirit of the present invention.

[0125] For example, the film-like adhesive composite sheet of this embodiment may or may not include other layers at any location that do not fall under any of the following categories: the base material, the adhesive layer, the film-like adhesive, or the release film. The aforementioned other layers can be arbitrarily selected depending on the purpose and are not particularly limited.

[0126] <Base material> The substrate may be in the form of a sheet or a film, and may be one of known types. The substrate is preferably one that allows energy rays to pass through. Examples of constituent materials for the base material include various resins. The resin constituting the base material may consist of only one type, or two or more types. If there are two or more types, their combination and ratio can be arbitrarily selected.

[0127] Examples of the aforementioned resins include polyolefins such as low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), high-density polyethylene (HDPE), and polypropylene; ethylene-based copolymers such as ethylene-vinyl acetate copolymer and ethylene-(meth)acrylic acid copolymer (polymers obtained using ethylene as a monomer); vinyl chloride resins (resins obtained using vinyl chloride as a monomer); polyester; polyurethane; polyurethane acrylate; and polyimide. The aforementioned resin may be any of the following: a polymer alloy such as a mixture of two or more of the above-mentioned resins; a crosslinked resin obtained by crosslinking one or more of the above-mentioned resins; or a modified resin such as an ionomer using one or more of the above-mentioned resins. In particular, a film-like adhesive composite sheet without an adhesive layer, where the base material is polyolefin, polyester, polyurethane, or polyurethane acrylate, is preferable because when the vacuum chamber of the plasma irradiation device is evacuated, the volatilization of the contained components is suppressed, and the desired vacuum level can be achieved in a short time.

[0128] In addition to the main constituent materials such as the aforementioned resin, the base material may also contain various known additives such as fillers, colorants, antioxidants, organic lubricants, catalysts, and plasticizers.

[0129] The surface of the substrate may or may not be treated with oxidation, lipophilicity, hydrophilicity, or primer treatment, and may or may not have other layers deposited on it.

[0130] The substrate thickness is preferably 50 to 300 μm. A substrate thickness within this range improves the flexibility of the film-like adhesive composite sheet and its suitability for adhesion to wafers.

[0131] The substrate can be manufactured by known methods. For example, a substrate containing a resin can be manufactured by molding a resin composition containing the resin.

[0132] <Adhesive layer> The adhesive layer contains an adhesive resin, which may be either energy-ray curable or non-energy-ray curable, and may be a known type.

[0133] <Release film> The release film may be a known type, for example, one or both sides of a release film substrate being a release surface.

[0134] ◇Method of manufacturing a film-like adhesive composite sheet The film-like adhesive composite sheet of this embodiment can be manufactured by laminating the above-mentioned layers in corresponding positional relationships and, if necessary, adjusting the shape of some or all of the layers. The method for forming each layer is as described above. The film-like adhesive composite sheet of this embodiment can be manufactured in the same way as a conventional film-like adhesive composite sheet, except that the film-like adhesive is used.

[0135] For example, when laminating a film-like adhesive onto a substrate, the adhesive composition is applied to a release film and dried as necessary to form a film-like adhesive on the release film. Then, the exposed surface of this film-like adhesive is bonded to one side of the substrate.

[0136] ◇Method for manufacturing workpieces with film-like adhesive (Method for using film-like adhesive and film-like adhesive composite sheets) The aforementioned film-like adhesive and film-like adhesive composite sheet can be used to manufacture workpieces coated with the film-like adhesive, and the resulting workpieces coated with the film-like adhesive can further be used to manufacture substrate devices. A method for manufacturing a workpiece with a film-like adhesive according to one embodiment of the present invention includes a workpiece group holder comprising a support sheet, a film-like adhesive provided on one surface of the support sheet, and a plurality of workpieces held in alignment on the side of the film-like adhesive opposite to the side of the support sheet, and a step of producing a workpiece group holder with a film-like adhesive in which a plurality of workpieces with film-like adhesive provided on one surface of the support sheet are held in alignment, by irradiating the film-like adhesive exposed between the plurality of workpieces in the workpiece group holder with plasma from the side of the plurality of workpieces, dry etching the film-like adhesive and cutting the film-like adhesive along the workpieces, wherein the film-like adhesive is the film-like adhesive according to the above embodiment.

[0137] Since the film-like adhesive is the film-like adhesive according to the above embodiment, when plasma is irradiated from the side of the multiple workpieces onto the film-like adhesive exposed between the multiple workpieces, the time required to reach the target vacuum level in the vacuum chamber containing the film-like adhesive can be shortened compared to conventional methods, and the film-like adhesive can be cut quickly by plasma dicing.

[0138] In this specification, a workpiece is defined as a product obtained by machining a workpiece. Examples of the aforementioned workpieces include wafers and semiconductor device panels.

[0139] Examples of the aforementioned wafers include semiconductor wafers composed of elemental semiconductors such as silicon, germanium, and selenium, and compound semiconductors such as GaAs, GaP, InP, CdTe, ZnSe, and SiC; and insulating wafers composed of insulators such as sapphire and glass. For example, if the workpiece is a semiconductor wafer, the workpiece could be a semiconductor chip. A circuit is formed on one side of these wafers, and in this specification, the side of the wafer on which the circuit is formed is referred to as the "circuit side." The side of the wafer opposite to the circuit side is referred to as the "back side." A wafer is divided into chips by means of dicing or other methods. In this specification, as with the wafer, the side of the chip on which the circuit is formed is referred to as the "circuit side," and the side of the chip opposite the circuit side is referred to as the "back side." Both the circuit surface of the wafer and the circuit surface of the chip are provided with protruding electrodes such as bumps and pillars. Preferably, these protruding electrodes are made of solder.

[0140] The aforementioned semiconductor device panel is handled during the manufacturing process of a semiconductor device. A specific example of such a panel is a semiconductor device in which one or more electronic components are sealed with a sealing resin, and multiple such semiconductor devices are arranged planarly within a circular, rectangular, or other shaped area.

[0141] In this specification, "substrate device" means a device constructed by bonding and fixing a workpiece with a film-like adhesive to a circuit board using the film-like adhesive or its cured product. For example, if a semiconductor wafer is used as the workpiece, a semiconductor device can be considered as the substrate device.

[0142] The film-like adhesive can be laminated with a support sheet to form the aforementioned film-like adhesive composite sheet. This film-like adhesive composite sheet can be used in the same way as known die bonding sheets.

[0143] <Manufacturing method for semiconductor chips with film-like adhesive (Manufacturing method (1))> A method for manufacturing a semiconductor chip with a film-like adhesive, where the workpiece is a semiconductor wafer and the workpiece is a semiconductor chip, includes a semiconductor chip group holder comprising a support sheet, a film-like adhesive provided on one surface of the support sheet, and a plurality of semiconductor chips held in alignment on the side of the film-like adhesive opposite to the side of the support sheet, wherein the semiconductor chip group holder is manufactured by irradiating the film-like adhesive exposed between the plurality of semiconductor chips in the semiconductor chip group holder with plasma from the side of the plurality of semiconductor chips, dry etching the film-like adhesive, and cutting the film-like adhesive along the semiconductor chips, thereby manufacturing a semiconductor chip group holder with a film-like adhesive in which the plurality of semiconductor chips with film-like adhesive provided on one surface of the support sheet are held in alignment.

[0144] The manufacturing method (1) will be explained below with reference to the drawings. Figures 2A to 2D are cross-sectional views illustrating an example of manufacturing method (1). Here, we will explain manufacturing method (1) using the film-like adhesive composite sheet 101 shown in Figure 1. Please note that the diagrams used in the following explanation may be enlarged for convenience in order to make the features of the present invention easier to understand, and the dimensional ratios of each component may not be the same as in reality.

[0145] First, a semiconductor chip group holder 901 is prepared as shown in Figures 2A and 2B. The semiconductor chip group holder 901 can be fabricated by known methods. The semiconductor chip group holder 901 is constructed by holding a plurality of semiconductor chips 90 in an aligned state on the first surface 13a of the film-like adhesive 13 in the film-like adhesive composite sheet 101. All of the semiconductor chips 90 are held on the first surface 13a of the film-like adhesive 13 on their back surfaces 90b.

[0146] Multiple semiconductor chips 90 are obtained by splitting a semiconductor wafer 9 into individual pieces. The semiconductor wafer 9 can be separated into individual pieces using a known method. For example, using a laminate 900 in which the semiconductor wafer 9 is attached to a film-like adhesive composite sheet 101 as shown in Figure 2A, a mask (not shown) matching the desired size for individual pieces can be applied to the surface of the semiconductor wafer 9, and the wafer can be separated by plasma irradiation. The circuit surface 9a and back surface 9b of the semiconductor wafer 9 become the circuit surface 90a and back surface 90b of the semiconductor chip 90, respectively, after the semiconductor wafer 9 is divided. As a result, the semiconductor chip group holder 901 shown in Figure 2B is obtained. In this case, the film-like adhesive can also be cut by continuously irradiating it with plasma.

[0147] Other methods for individualizing the semiconductor chips include transferring the individualized semiconductor chips 90, which have been separated on a dicing tape using a blade, onto a film-like adhesive according to the present invention, or obtaining individualized semiconductor chips 90 by making grooves in a semiconductor wafer 9 and then performing thinning grinding. Furthermore, individual pieces can also be formed by creating a modified layer inside the semiconductor wafer 9 using a laser and then cutting the wafer from the modified layer using the pressure of back grinding. In individual pieces formed by creating a modified layer, there are no so-called kerfs between the semiconductor chips 90, so it is preferable to expand the spacing between multiple semiconductor chips 90 when transferring them onto the film-like adhesive according to the present invention.

[0148] Next, as shown in Figures 2B and 2C, plasma is irradiated from the side of the semiconductor chips 90 to the film-like adhesive 13 exposed between the multiple semiconductor chips 90 in the semiconductor chip group holder 901, thereby dry etching the film-like adhesive 13 and cutting the film-like adhesive 13 along the semiconductor chips 90. As a result, as shown in Figure 2C, multiple semiconductor chips 91 with film-like adhesive are fabricated, each comprising a semiconductor chip 90 and a pre-cut film-like adhesive 133 provided on the back surface 90b of the semiconductor chip 90.

[0149] Since the film-like adhesive 13 is the film-like adhesive according to the above-described embodiment, when plasma is irradiated from the side of the multiple semiconductor chips 90 to the film-like adhesive 13 exposed between the multiple semiconductor chips 90, the time required to bring the vacuum chamber containing the semiconductor chip group holder 901 to the target vacuum level can be shortened compared to conventional methods, and the film-like adhesive 13 can be cut quickly by plasma dicing. Even when plasma dicing a semiconductor wafer 9 and then subsequently plasma dicing the film-like adhesive 13, it is necessary to readjust the plasma irradiation conditions in the state of the semiconductor chip group holder 901 as shown in Figure 2B. In this case as well, since the film-like adhesive 13 is the film-like adhesive according to the above-described embodiment, when plasma is irradiated from the side of the multiple semiconductor chips 90 to the film-like adhesive 13 exposed between the multiple semiconductor chips 90, the time required to bring the vacuum chamber containing the semiconductor chip group holder 901 to the target vacuum level again can be shortened compared to conventional methods, and the film-like adhesive 13 can be cut quickly.

[0150] These multiple semiconductor chips 91 with film-like adhesive are aligned and held on a support sheet 10 (in other words, a substrate 11), and together with the support sheet 10, they constitute a semiconductor chip group holder 902 with film-like adhesive. The first surface 133a and the second surface 133b of the cut film-like adhesive 133 are derived from the first surface 13a and the second surface 13b of the film-like adhesive 13 before cutting, respectively.

[0151] When dry etching the film-like adhesive 13 by irradiating it with plasma from the side of multiple semiconductor chips 90, the plasma irradiation conditions are not particularly limited as long as the film-like adhesive 13 can be sufficiently dry-etched, and can be appropriately selected depending on the type of film-like adhesive 13. For example, when using SF6 gas, the plasma can be irradiated under the conditions of SF6 gas flow rate (sccm) / argon gas flow rate (sccm) being 50 / 3, under a reduced pressure environment of 20 Pa, and with an RF (Radio Frequency) power of 250 W. Similarly, when using O2 gas, the plasma can be irradiated under the conditions of O2 gas flow rate (sccm) / argon gas flow rate (sccm) being 50 / 3, under a reduced pressure environment of 20 Pa, and with an RF (Radio Frequency) power of 250 W.

[0152] In this specification, not only in the case of manufacturing method (1), "pre-cut film-like adhesive" may be simply referred to as "film-like adhesive."

[0153] The semiconductor chip group holder with film adhesive is constructed by holding multiple semiconductor chips with film adhesive in an aligned state on the first surface 10a of a support sheet 10. All of the semiconductor chips with film adhesive are held on the first surface 10a of the support sheet 10 by the second surface of the cut film adhesive.

[0154] In the semiconductor chip group holder 902 with film adhesive shown in Figure 2C, the semiconductor chips 91 with film adhesive can be pulled away from the support sheet 10 and picked up, as shown in Figure 2D. At this time, delamination occurs between the second surface 133b of the cut film adhesive 133 in the semiconductor chip 91 and the first surface 10a of the support sheet 10 (the first surface 11a of the substrate 11). If necessary, the support sheet 10 can be expanded to increase the distance between the semiconductor chips 91 with film adhesive before picking them up.

[0155] ◇Manufacturing method for substrate devices (Method of using workpieces with film-like adhesive) A substrate device can be manufactured using the workpiece with film-like adhesive obtained by the manufacturing method described above. The substrate device can be manufactured by known methods, except for the use of the workpiece with the aforementioned film-like adhesive. For example, a workpiece with a film-like adhesive attached can be mounted on a circuit board by bonding it to the circuit board using the film-like adhesive or the cured adhesive (cured film-like adhesive) contained within it (mounting process). If the film-like adhesive is thermosetting, the workpiece can be firmly fixed to the circuit board by further thermosetting the film-like adhesive after mounting. The film-like adhesive may also be thermosetting simultaneously by heating when the workpiece is sealed on the circuit board with resin. In addition to mounting the workpiece onto the circuit board, the desired circuit board device can be manufactured by adding other processes as needed. [Examples]

[0156] The present invention will be described in more detail below with reference to specific examples. However, the present invention is not limited in any way to the examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or other reasons, the desired measurements can be performed using other instruments with equivalent performance.

[0157] <<Raw materials for resin manufacturing>> The full names of the resin manufacturing raw materials, which are abbreviated in this example and comparative example, are shown below. BA: n-butyl acrylate MA: Methyl acrylate GMA: Glycidyl methacrylate HEA: 2-hydroxyethyl acrylate

[0158] <<Raw materials for manufacturing adhesive compositions>> The raw materials used in the manufacture of the adhesive composition are listed below. [Acrylic resin (a1)] (a1)-1: Acrylic resin obtained by copolymerizing BA (55 parts by mass), MA (10 parts by mass), GMA (20 parts by mass), and HEA (15 parts by mass) (weight-average molecular weight: 800,000, glass transition temperature: -28°C). (a1)-2: Acrylic resin obtained by copolymerizing BA (10 parts by mass), MA (70 parts by mass), GMA (5 parts by mass), and HEA (15 parts by mass) (weight-average molecular weight: 400,000, glass transition temperature: -1°C). [Polyester resin (a2)] (a2)-1: Amorphous polyester resin (manufactured by Toyobo MC Corporation, Byron® 220, number average molecular weight (Mn): 3000, glass transition temperature: 53℃)

[0159] [Epoxy resin (b1)] (b1)-1: Liquid bisphenol F type epoxy resin (YL983U manufactured by Mitsubishi Chemical Corporation, epoxy equivalent 169 g / eq) (b1)-2: Dicyclopentadiene type epoxy resin (DIC Corporation's "Epiclon" (registered trademark) HP-7200HH, epoxy equivalent 274-286 g / eq) [Thermosetting agent (b2)] (b2)-1: Dicyandiamide (ADEKA Corporation's "ADEKA Hardener® EH-3636AS", solid dispersion latent curing agent, softening point 209°C, hydroxyl group equivalent 21 g / eq) [Curing accelerator (c)] (c)-1:2-phenyl-4,5-dihydroxymethylimidazole (Shikoku Chemicals Co., Ltd. "Curesol (registered trademark) 2PHZ-PW") [Filler (d)] (d)-1: Silica filler (SC2050MA, manufactured by Admatex, silica filler surface modified with epoxy compounds, average particle size 0.5 μm)

[0160] <<Manufacturing of film-type adhesives>> [Example 1] <Manufacturing of adhesive compositions> Adhesive compositions were prepared by dissolving or dispersing each component in methyl ethyl ketone and stirring at 23°C, so that the types and amounts of components contained in the film-like adhesive were as shown in Table 1, and the mixture was stirred to obtain an adhesive composition in which the total concentration of all components other than the solvent was 50% by mass. In Table 1, a "-" in the "Components (Content (parts by mass))" column indicates that the film adhesive does not contain that component. This is also true for other tables.

[0161] <Manufacturing of film-type adhesives> A release film (second release film, Lintec Corporation's "SP-PET381031", thickness 38 μm) made of polyethylene terephthalate film, in which one side was treated with silicone to release the adhesive, was used. The adhesive composition obtained above was applied to the treated surface and dried at 110°C for 1 minute to produce a 20 μm thick film-like adhesive. Furthermore, the treated surface of a separate release film (first release film, Lintec Corporation's "SP-PET381031", thickness 38 μm) was bonded to the exposed surface of the obtained film-like adhesive to produce a film-like adhesive with release films on both sides.

[0162] [Examples 2-7, Comparative Example 1] <Manufacturing of adhesive compositions and film-like adhesives> Except for changing the type of components in the adhesive composition, or the type and amount of components, so that the types and amounts of components in the film adhesive are as shown in Tables 1 to 2, the film adhesives with release films (film adhesives with a thickness of 20 μm) of Examples 2 to 7 and Comparative Example 1 were manufactured using the same method as in Example 1.

[0163] <<Evaluation of film-type adhesives>> <Measurement of weight loss rate (ΔW1) after heating at 200°C for 1 hour> For the film-like adhesives of Examples 1-7 and Comparative Example 1, approximately 5 mg of test specimens were heated using a TG / DTA simultaneous measurement device (Shimadzu Corporation, DTG-60) from 40°C to 200°C at a heating rate of 10°C / min, and then held at 200°C for 1 hour. The weight loss rate (ΔW1) [weight %] was calculated from the weight of the film-like adhesive before heating (W0) and the weight of the film-like adhesive after heating (W1) using the following formula (1). The results are shown in Tables 1 and 2. ΔW1=(W0-W1) / W0×100 (1)

[0164] Cases where the weight loss rate (ΔW1) [weight %] is 10% by weight or less are indicated as A, and cases where it exceeds 10% by weight are indicated as B.

[0165] <5×10 ―5 Measurement of the time [min] taken to reduce the pressure to Pa > The plasma irradiation device is connected to an Adixen vacuum pump and has a chamber capacity of approximately 5000 cm³. 3 Using a dry etching apparatus (Samco RIE-10NR), various test pieces were placed in the chamber, and 5 × 10 ―5 The time [min] required to reduce the pressure to Pa was measured. As test specimens, the release film from one side of the release film attached to the film adhesive prepared in Examples 1-7 and Comparative Example 1 above was used. The measurement results are shown in Tables 1 and 2.

[0166] Achieve the target vacuum level of 5x10 within 20 minutes. ―5 A indicates that Pa is reached, and the target vacuum level of 5 × 10⁻¹⁰ is reached within 20 minutes. ―5 The case where Pa was not reached is indicated as B.

[0167] [Table 1]

[0168] [Table 2]

[0169] As is clear from the above results, in the film-like adhesive of Comparative Example 1, the weight loss rate (ΔW1) when the film-like adhesive was heated at 200°C for 1 hour was more than 10%, and the target vacuum level was 5 × 10 ―5 In contrast to the long time (min) required to reduce the pressure to Pa, the film-like adhesives of Examples 1-7 show a weight loss rate (ΔW1) of 10% or less when the film-like adhesive is heated at 200°C for 1 hour, so 5 × 10 ―5 We were able to reduce the time (in minutes) required to reduce the pressure to Pa. As a result, plasma dicing can now be used to quickly cut film-like adhesives. [Industrial applicability]

[0170] This invention can be used in the manufacture of substrate devices. [Explanation of Symbols]

[0171] 10...Support sheet, 10a...First side of the support sheet 11...Base material 13...Film-type adhesive, 13a...First side of film-type adhesive 101...Film-type adhesive composite sheet 133... Pre-cut film-type adhesive 9... Semiconductor wafer, 90... Semiconductor chip, 90b... Back side of semiconductor chip 900...Laminate 901... Semiconductor chip group holder 902... Semiconductor chip group holder with film-like adhesive 91... Semiconductor chip with film-type adhesive

Claims

1. A film-like adhesive for use in plasma dicing, The weight loss rate (ΔW) of the aforementioned film-like adhesive when heated at 200°C for 1 hour. １ A film-type adhesive in which the content of ) is 10% or less.

2. The film-like adhesive according to claim 1, wherein the film-like adhesive contains a filler (d), and the ratio of the content of the filler (d) to the total mass of the film-like adhesive is 2% by mass or more.

3. The film-like adhesive according to claim 1, wherein the film-like adhesive contains an epoxy resin (b1) which is solid at room temperature, and the ratio of the content of the epoxy resin (b1) which is solid at room temperature to the total mass of the epoxy resin (b1) is 50% by mass or more.

4. The film-like adhesive according to claim 1, wherein the film-like adhesive contains an epoxy resin (b1), and the ratio of the epoxy resin (b1) content to the total mass of the film-like adhesive is 30% by mass or more and 80% by mass or less.

5. The film-like adhesive according to claim 1, wherein the film-like adhesive contains a binder resin (a), and the weight-average molecular weight (Mw) of the binder resin (a) is greater than 3000.

6. The invention comprises a base material and a film-like adhesive provided on one surface of the base material, A film-like adhesive composite sheet wherein the film-like adhesive is the film-like adhesive described in any one of claims 1 to 5.

7. The process includes using a workpiece group holder comprising a support sheet, a film-like adhesive provided on one surface of the support sheet, and a plurality of workpieces held in alignment on the side of the film-like adhesive opposite to the side of the support sheet, to produce a workpiece group holder with film-like adhesive attached in which a plurality of workpieces with film-like adhesive attached provided on one surface of the support sheet are held in alignment, by irradiating the film-like adhesive exposed between the plurality of workpieces in the workpiece group holder with plasma from the side of the plurality of workpieces, dry etching the film-like adhesive and cutting the film-like adhesive along the workpieces, A method for manufacturing a workpiece coated with a film-like adhesive, wherein the film-like adhesive is the film-like adhesive described in any one of claims 1 to 5.

Images