Method for manufacturing film-like adhesives, film-like adhesive composite sheets, and film-like adhesive-coated chips

Abstract

The present invention provides a film-like adhesive that cuts quickly by plasma dicing, a film-like adhesive composite sheet equipped with the film-like adhesive, and a method for manufacturing a film-like adhesive-coated chip using the film-like adhesive. [Solution] A film-like adhesive 13 for use in plasma dicing, wherein the film-like adhesive 13 contains a binder resin (a) and a thermosetting component (b), and the weight loss rate of the film-like adhesive 13 when heated at 200°C for 1 hour is 6% by weight or more. A film-like adhesive composite sheet 101 comprising a support sheet 10 and a film-like adhesive 13 provided on one surface 10a of the support sheet 10.

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a film-like adhesive, a film-like adhesive composite sheet, and a chip coated with a film-like adhesive. [Background technology]

[0002] In the manufacturing of semiconductor devices, for example, a semiconductor chip with a film-like adhesive is manufactured, which comprises a semiconductor chip and a film-like adhesive provided on the back surface (the side opposite to the circuit surface) of the semiconductor chip. This film-like adhesive is then bonded and fixed to a circuit board using the film-like adhesive, and mounted. The film-like adhesive is usually thermosetting, meaning it hardens when heated. After bonding the semiconductor chip with the film-like adhesive to the circuit board, the film-like adhesive is heat-cured to fix the semiconductor chip to the circuit board.

[0003] The aforementioned film-like adhesive-coated semiconductor chip can be manufactured, for example, by the following method. Specifically, first, one film-like adhesive composite sheet (for example, a dicing die bonding sheet) is used, which comprises a support sheet and a film-like adhesive provided on one surface of the support sheet, and the film-like adhesive within the composite sheet is attached to the back surface of a semiconductor wafer. Next, on the support sheet, the semiconductor wafer is divided to produce semiconductor chips, and the film-like adhesive is cut, thereby producing multiple semiconductor chips with the film-like adhesive on the support sheet. (See Patent Document 1).

[0004] The aforementioned film-like adhesive semiconductor chip can also be manufactured by, for example, the following method. Specifically, first, numerous parallel grooves are formed on the semiconductor wafer in two directions that are perpendicular to each other, while remaining parallel to the circuit surface, extending from the circuit surface towards the back surface. At this time, the spacing between adjacent grooves is adjusted to obtain a semiconductor chip of the desired size. 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, one of the aforementioned film-like adhesive composite sheets (for example, a die bonding sheet) is used, and the film-like adhesive within it is attached to the back surface (in other words, the ground 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, and 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, some film-type adhesives have the problem of being slow to cut by plasma dicing.

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

[0012] The present invention aims to provide a film-like adhesive that cuts quickly by plasma dicing, a film-like adhesive composite sheet equipped with the film-like adhesive, and a method for manufacturing a film-like adhesive-coated chip using 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, wherein the film-like adhesive contains a binder resin (a) and a thermosetting component (b), and the weight loss rate of the film-like adhesive when heated at 200°C for 1 hour is 6% by weight or more. [2] The film-like adhesive according to [1], wherein the weight-average molecular weight of the binder resin (a) is 850,000 or less. [3] The film-like adhesive according to [1] or [2], wherein the film-like adhesive does not contain filler (d), or contains filler (d), and the ratio of the content of filler (d) to the total mass of the film-like adhesive is 5% by mass or less. [4] The film-like adhesive according to any one of [1] to [3], wherein the film-like adhesive contains an epoxy resin (b1) and a thermosetting agent (b2) as the thermosetting component (b), and the film-like adhesive contains an epoxy resin (b1) that is solid at room temperature.

[0014] [5] A film-like adhesive composite sheet comprising a support sheet and a film-like adhesive provided on one surface of the support sheet, wherein the film-like adhesive is the film-like adhesive according to any one of [1] to [4]. [6] The film-like adhesive composite sheet according to [5], wherein the support sheet consists only of a base material.

[0015] [7] A method for manufacturing a chip with a film-like adhesive, comprising a chip and a film-like adhesive provided on one surface of the chip. In the manufacturing method, a dicing die bonding sheet comprising the film-like adhesive according to any one of [1] to [4] and a dicing sheet provided on one surface of the film-like adhesive, or the film-like adhesive composite sheet according to [5] or [6] is used. The surface of the film-like adhesive in the dicing die bonding sheet or the film-like adhesive composite sheet, which is opposite to the side of the dicing sheet or the support sheet, is pasted on one surface of a wafer. On the dicing sheet or the support sheet, plasma is irradiated from the outside of the wafer side to the wafer and the film-like adhesive to divide the wafer to produce the chip, and by cutting the film-like adhesive, a chip with the film-like adhesive having been cut is obtained. A method for manufacturing a chip with a film-like adhesive. [Effect of the Invention]

[0016] According to the present invention, there are provided a film-like adhesive having a high cutting speed by plasma dicing, a film-like adhesive composite sheet including the film-like adhesive, and a method for manufacturing a chip with a film-like adhesive using the film-like adhesive. [Brief Description of the Drawings]

[0017] [Figure 1] It is a cross-sectional view for schematically explaining a method for measuring the cutting speed during plasma dicing of a film-like adhesive according to an embodiment of the present invention. [Figure 2]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 3] This is a schematic cross-sectional view illustrating a method for manufacturing a semiconductor chip 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 film-like adhesive contains a binder resin (a) and a thermosetting component (b), and the weight loss rate (sometimes referred to as "ΔW1" in this specification) when the film-like adhesive is heated at 200°C for 1 hour is 6% by weight or more. The film-like adhesive of this embodiment can be used to manufacture a chip coated with a film-like adhesive, comprising a chip and the film-like adhesive provided on one side of the chip. In this case, the weight loss rate (ΔW1) of the film-like adhesive is 6% by weight or more, which allows for a fast cutting speed of the film-like adhesive by plasma dicing.

[0019] The cutting of film-like adhesives by plasma irradiation proceeds through etching of the film-like adhesive by the plasma; therefore, the cutting speed is synonymous with the etching speed.

[0020] The aforementioned film-like adhesive-coated chip can be used in the manufacturing of the substrate device described later.

[0021] In this specification, "film adhesive" means a film adhesive that has not undergone both intentional thermal curing and intentional energy ray curing, unless otherwise specified.

[0022] In this specification, the 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 wafer is a semiconductor wafer, then the chip would be a semiconductor chip. One side of these wafers is the circuit side, on which the circuit is formed, and the side opposite to this is referred to in this specification as the "back side". The same applies to chips manufactured by dividing a wafer through methods such as dicing; the side of the chip opposite the circuit side on which the circuit is formed is called 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.

[0023] In this specification, "substrate device" means a device constructed by bonding and fixing a film-like adhesive chip to a circuit board using that film-like adhesive. For example, if a semiconductor wafer is used as the wafer, a semiconductor device can be considered a substrate device.

[0024] 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 support 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.

[0025] The film-like adhesive of this embodiment is thermosetting and may or may not be energy-ray curable (i.e., it may be either energy-ray curable or non-energy-ray curable). Preferably, the film-like adhesive of this embodiment is thermosetting and not energy-ray curable. The thermosetting product formed by thermosetting the film-like adhesive or its energy-ray cured product that adheres and fixes chips to a circuit board in a substrate device has high impact resistance and maintains sufficient adhesive properties even under severe high temperature and high humidity conditions.

[0026] 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. "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. "Thermosetting" refers to the property of hardening when heated.

[0027] 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 thermal curing of the film-like adhesive and its energy-ray cured product is preferably 100 to 200°C. The heating time during thermal curing is preferably 0.5 to 5 hours. During the energy ray curing of film-type adhesives, the illuminance of the energy rays is 60-320 mW / cm². 2 Preferably, the amount of light from the energy ray during the energy ray curing process is 100 to 1000 mJ / cm². 2 It is preferable that this be the case.

[0028] 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 oxygen (O2) gas.

[0029] <<Weight loss rate (ΔW1) when film-type adhesive is heated at 200°C for 1 hour>> The weight loss rate (ΔW1) of the film-like adhesive of this embodiment when heated at 200°C for 1 hour is 6% by weight or more. Because ΔW1 is above this specific value, the plasma dicing speed of the film-like adhesive is fast. To make the effect of such a film-like adhesive more pronounced, ΔW1 may be, for example, 6.8% by weight or more, or 8% by weight or more. On the other hand, film-like adhesives with ΔW1 of 11% by weight or less can be produced more easily.

[0030] The weight loss rate (ΔW1) can be adjusted, for example, by adjusting the types and amounts of components contained in the film-like adhesive. In particular, ΔW1 can be increased by setting the weight-average molecular weight of the binder resin (a) to below a specific value as described later, increasing the amount of such binder resin (a) in the film-like adhesive, reducing the amount of filler (d) described later in the film-like adhesive, selecting epoxy resin (b1) and thermosetting agent (b2) as the thermosetting component (b), and selecting an epoxy resin (b1) that is solid at room temperature. The components of the film-like adhesive in this embodiment will be described in detail later.

[0031] The weight loss rate (ΔW1) of the film-like adhesive can be measured, for example, by thermogravimetric-differential thermal analysis (TG-DTA) using the following method. Specifically, a small piece of an appropriate amount (for example, about 3 to 10 g) is cut from the film-like adhesive, and this is used as a test piece. Using TG-DTA, the test piece is heated in an air atmosphere at a heating rate of 10°C / min from 40°C to 200°C, and then heated at 200°C for 1 hour to obtain a heated object. Then, the weight loss rate ΔW1 of the film-like adhesive is calculated from the weight of the film-like adhesive before heating (W0) and the weight of the heated film-like adhesive (W1) according to the following formula (i). ΔW1 = W1 / W0 × 100 (i)

[0032] <Cutting speed of film-type adhesives during plasma dicing> The method for measuring the cutting speed during plasma dicing of film-like adhesives will be explained with reference to 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.

[0033] First, as shown in Figure 1(a), a test specimen 6 is prepared, comprising a film-like adhesive 13, a mask 7 attached to one side (sometimes referred to as the "first side" in this specification) 13a of the film-like adhesive 13, and a support 8 attached to the other side of the film-like adhesive 13.

[0034] The material of the mask 7 is not particularly limited as long as it can suppress the transmission of plasma, and may be, for example, an adhesive tape containing a high-strength resin such as polyimide as its main component. The shape, size, and position of the mask 7 are not particularly limited, as long as the exposed area of ​​the first surface 13a of the film-like adhesive 13 and the area masked (shielded) by the mask 7 are both of sufficient size.

[0035] The support 8 is not particularly limited as long as it can hold the film-like adhesive 13 when irradiated with plasma, and may be, for example, a sheet or plate made of resin or an inorganic material. The support 8 may be, for example, a semiconductor wafer or a semiconductor chip.

[0036] Then, the test piece 6 is irradiated with plasma P from the first surface 13a of the film-like adhesive 13. This etches the areas of the film-like adhesive that are not masked by the mask 7, as shown in Figure 1(b). In this case, if etching of the film-like adhesive 13 in the area to which the mask 7 is attached is suppressed, the mask 7 itself may or may not be etched.

[0037] After irradiation with plasma P (after etching), as shown in Figure 1(c), the mask 7 is removed from the film-like adhesive 13, and the height difference between the original first surface 13a of the film-like adhesive 13 (the surface of the film-like adhesive 13 that was masked by the mask 7) and the etched surface 13a' of the film-like adhesive 13 (the surface of the film-like adhesive 13 that was not masked by the mask 7), i.e., the etching distance L, is measured. The etching distance L may be measured as surface roughness using, for example, a surface roughness measuring instrument, or it may be measured using a laser microscope or the like.

[0038] Alternatively, after irradiation with plasma P (after etching), without removing the mask 7, the thickness of the test piece 6 in the area with the mask 7 (i.e., the total thickness of the support 8, the film adhesive 13, and the mask 7) T can be determined. 60 The thickness of the film-like adhesive 13 in the etched region (i.e., the total thickness of the support 8 and the etched film-like adhesive 13) T 61 The thickness T7 of the mask 7 after irradiation with plasma P was measured separately under the same conditions, and T 60 From T 61 Subtract T7 (T 60 -T 61The etching distance L can be calculated by (calculating the value of -T7).

[0039] Finally, the etching rate is calculated from the plasma irradiation time (etching time) t and L, using the formula L / t, and this is adopted as the cutting rate of the film-like adhesive.

[0040] To improve the accuracy of etching rate measurement, the etching distance L is preferably 0.5 μm or more, and more preferably 1 μm or more.

[0041] For example, by measuring the cutting speed during plasma dicing of both the film-like adhesive of this embodiment and a comparative film-like adhesive under arbitrary and identical conditions, and comparing these measured values, the superiority of the cutting speed of the film-like adhesive of this embodiment can be determined.

[0042] For example, with respect to the film-like adhesive of this embodiment, the cutting speed during plasma dicing, measured using plasma generated from oxygen (O2) gas under the conditions described in the later examples, is preferably 0.2 μm / min or higher, and may be any of the following: 0.5 μm / min or higher, 1 μm / min or higher, 1.5 μm / min or higher, and 2 μm / min or higher. On the other hand, a film-like adhesive with a cutting speed of 3.5 μm / min or less can be more easily realized.

[0043] <Other components of film-type adhesives> The film-like adhesive of this embodiment is suitable for storage in roll form, for example, by having a first release film on one side and a second release film on the other side opposite to the first side. One of the two surfaces of the film-like adhesive becomes the surface for attachment to the wafer, and the other becomes the surface for attachment to the support sheet or dicing sheet, as described later. 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 identical to each other, or they may be different, for example, having different peeling forces when peeled from a film-like adhesive.

[0044] 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.

[0045] 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."

[0046] The thickness of the film-like adhesive is preferably 3 to 25 μm, more preferably 4 to 20 μm, and may be, for example, 5 to 15 μm. A film-like adhesive thickness greater than or equal to the lower limit increases the strength of the film-like adhesive and improves the uniformity of its thickness. A film-like adhesive thickness less than or equal to the upper limit avoids excessive thickness. This allows the film-like adhesive to be cut more easily, for example, by plasma dicing. 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. This also applies to other layers such as the substrate, which will be discussed later.

[0047] 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.

[0048] <<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.

[0049] In this specification, "room temperature" means a temperature that is neither cooled nor heated, i.e., a normal temperature, such as 18-28°C.

[0050] 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.

[0051] 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.

[0052] Examples of the adhesive composition include a composition containing a binder resin (a) and a thermosetting component (b) (which may be abbreviated as "composition (III)" in this specification), and it is preferable that the adhesive composition further contains a curing accelerator (c).

[0053] The binder resin (a), thermosetting component (b), and curing accelerator (c) 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.

[0054] <Binder resin (a)> Binder resin (a) is a component that can be considered to be formed by a polymerization reaction of polymerizable compounds, and is a polymer compound for imparting film-forming properties, flexibility, etc., to film-like adhesives. In this specification, polymer compounds also include products of polycondensation reactions. On the other hand, binder resin (a) is also a component that cuts faster during plasma dicing than most other components that are expected to be included in film-like adhesives.

[0055] Examples of binder resin (a) include acrylic resin, saturated polyester resin, urethane resin, phenoxy resin, and silicone resin, with acrylic resin and saturated polyester resin being preferred, and acrylic resin being more preferred.

[0056] The weight-average molecular weight (Mw) of the binder resin (a) is preferably 850,000 or less, and may be, for example, 800,000 or less, 700,000 or less, 600,000 or less, or 500,000 or less. By having a weight-average molecular weight of the binder resin (a) that is below the upper limit, the weight reduction rate (ΔW1) of the film-like adhesive can be increased more easily, and as a result, the cutting speed of the film-like adhesive during plasma dicing becomes faster. On the other hand, in terms of achieving better film-forming properties of the film-like adhesive, it is preferable that the weight-average molecular weight of the binder resin (a) be 100,000 or more.

[0057] Furthermore, the larger the weight-average molecular weight of the binder resin (a) is within the above numerical range, the better the shape stability (stable over time during storage) of the film-like adhesive; and the smaller the molecular weight, the easier the film-like adhesive is to conform to the uneven surface of the adherend.

[0058] The weight-average molecular weight (Mw) of the binder resin (a) may be appropriately adjusted within a range of 850,000 or less, depending on the type of binder resin (a).

[0059] For example, if the binder resin (a) is the acrylic resin, the weight-average molecular weight (Mw) of the binder resin (a) (acrylic resin) is preferably 850,000 or less for the same reasons as above, and may be any of 800,000 or less, 700,000 or less, 600,000 or less, and 500,000 or less. On the other hand, the weight-average molecular weight (Mw) of the binder resin (a) (acrylic resin) is preferably 350,000 or more for the same reasons as above. When the binder resin (a) is the acrylic resin, the weight-average molecular weight (Mw) of the binder resin (a) (acrylic resin) is preferably 350,000 to 600,000, as this improves both the weight loss rate (ΔW1) and film-forming properties of the film-like adhesive. For example, it may be 350,000 to 550,000 or 350,000 to 450,000.

[0060] For example, if the binder resin (a) is the saturated polyester resin, the weight-average molecular weight (Mw) of the binder resin (a) (saturated polyester resin) is preferably 80,000 or less for the same reasons as above, and may be, for example, 60,000 or less, 50,000 or less, or 40,000 or less. On the other hand, the weight-average molecular weight (Mw) of the binder resin (a) (saturated polyester resin) is preferably 10,000 or more for the same reasons as above.

[0061] In this specification, not only in the case of binder resin (a), but also in general, both "weight-average molecular weight" and "number-average molecular weight" are polystyrene-converted values ​​measured by gel permeation chromatography (GPC), unless otherwise specified.

[0062] Of the binder resins (a), the glass transition temperature (Tg) of the acrylic resin is preferably -60 to 70°C, more preferably -50 to 40°C, and even more preferably -35 to 15°C, and may be, for example, -20 to 15°C and -10 to 15°C. Having a Tg of the acrylic resin above the lower limit makes it easier to increase the weight loss rate (ΔW1) of the film-like adhesive. Furthermore, the adhesive strength between the film-like adhesive and the adherend is suppressed, making it easier to pick up the film-like adhesive-coated chip from the support sheet or dicing sheet described later. On the other hand, having a Tg of the acrylic resin below the upper limit improves the film-forming properties of the film-like adhesive. Furthermore, the adhesive strength between the film-like adhesive and the chip is improved.

[0063] When an acrylic resin has two or more constituent units, the glass transition temperature (Tg) of the acrylic resin 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.

[0064] [Acrylic resin] Examples of the acrylic resin include known acrylic polymers, more specifically, polymers of one or more (meth)acrylic acid esters; copolymers of two or more monomers selected from the (meth)acrylic acid ester, (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, and N-methylolacrylamide, etc.

[0065] 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.

[0066] Examples of the (meth)acrylic acid esters that constitute the acrylic resin include alkyl (meth)acrylates, cycloalkyl (meth)acrylates, hydroxyl group-containing (meth)acrylic acid esters, and glycidyl group-containing (meth)acrylic acid esters.

[0067] Examples of the alkyl (meth)acrylate esters include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate, in which the alkyl group constituting the alkyl ester has a chain structure (linear or branched) with 1 to 18 carbon atoms. The number of carbon atoms in the alkyl group is preferably 1 to 12, and may be any of 1 to 10, 1 to 8, or 1 to 6.

[0068] Examples of the (meth)acrylate cycloalkyl ester include isobornyl (meth)acrylate and dicyclopentanyl (meth)acrylate, in which the cycloalkyl group constituting the cycloalkyl ester has a cyclic structure (monocyclic or polycyclic) with 6 to 18 carbon atoms.

[0069] Examples of the hydroxyl group-containing (meth)acrylic acid esters include 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, in which the hydroxyalkyl group constituting the hydroxyalkyl ester has a chain structure (linear or branched) with 1 to 18 carbon atoms. The number of carbon atoms in the hydroxyalkyl group is preferably 1 to 12, and may be any of 1 to 10, 1 to 8, or 1 to 6.

[0070] Examples of the glycidyl group-containing (meth)acrylic acid ester include (meth)acrylic acid glycidyl, in which the glycidyl group-containing group constituting the ester has 3 to 18 carbon atoms. The number of carbon atoms in the glycidyl group-containing group is preferably 3 to 12, and may be any of 3 to 10, 3 to 8, or 3 to 6.

[0071] The monomers that make up the acrylic resin 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.

[0072] The acrylic resin may or may not have functional groups that can bond to other compounds, such as vinyl groups, (meth)acryloyl groups, amino groups, carboxyl groups, and isocyanate groups, in addition to the hydroxyl groups and glycidyl groups described above. The functional groups of the acrylic resin may be bonded to other compounds via a crosslinking agent (f) described later, or they may be directly bonded to other compounds without the crosslinking agent (f).

[0073] [Saturated polyester resin] The saturated polyester resin comprises structural units derived from polycarboxylic acids and structural units derived from polyols. The constituent units derived from polycarboxylic acids and those derived from polyols in a saturated polyester resin may be one type each, or two or more types each. If there are two or more types, their combinations and ratios can be arbitrarily selected.

[0074] Examples of the polycarboxylic acid 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.

[0075] Examples of the aforementioned polyol 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.

[0076] The saturated polyester resin is preferably an amorphous saturated polyester resin.

[0077] In terms of superior cohesive strength and mechanical strength of saturated polyester resins, the number-average molecular weight of the saturated polyester resin is preferably 500 to 100,000, and may be, for example, 1,000 to 80,000 or 1,500 to 50,000. These number-average molecular weights are particularly preferred when the saturated polyester resin is an amorphous saturated polyester resin.

[0078] In the film-like adhesive, the ratio of the total content (parts by mass) of acrylic resin and saturated polyester resin to the total content (parts by mass) of binder resin (a) is preferably 80% by mass or more, more preferably 90% by mass or more, and may be, for example, 93% by mass or more and 95% by mass or more. When the ratio is above the lower limit, the cutting speed of the film-like adhesive during plasma dicing becomes faster. On the other hand, the aforementioned ratio is 100% by mass or less. Here, if the film-like adhesive does not contain acrylic resin as the binder resin (a), the acrylic resin content is 0 parts by mass. The same applies to saturated polyester resin.

[0079] In a film-like adhesive, the ratio of the binder resin (a) content to the total mass of the film-like adhesive is preferably 10 to 40% by mass, regardless of the type of binder resin (a), and may be, for example, 10 to 30% by mass or 10 to 23% 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 binder resin (a) is suppressed.

[0080] The above-mentioned statement regarding the ratio of the binder resin (a) content to the total mass of the film-like adhesive is equivalent to stating that in composition (III), the ratio of the binder resin (a) content to the total content of all components other than the solvent is preferably 10 to 40% by mass, regardless of the type of binder resin (a), and may be, for example, 10 to 30% by mass and 10 to 23% 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.

[0081] <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. 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.

[0082] [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.

[0083] (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.

[0084] In terms of achieving a faster cutting speed during plasma dicing of film-like adhesives, the epoxy equivalent of the epoxy resin (b1) is preferably 100 to 1000 g / eq, more preferably 100 to 600 g / eq, and even more preferably 150 to 300 g / eq.

[0085] In terms of increasing the cutting speed during plasma dicing of the film-like adhesive, the softening point of the epoxy resin (b1) is preferably 40 to 150°C, more preferably 50 to 100°C, and may be, for example, 60 to 90°C.

[0086] It is preferable that the epoxy resin (b1) is solid at room temperature, as this provides particularly excellent film-forming properties and adhesive characteristics for the film-like adhesive, and also allows for easier increase of the ΔW1 of the film-like adhesive, resulting in a faster cutting speed during plasma dicing of the film-like adhesive. Specifically, it is preferable that the film-like adhesive contains epoxy resin (b1) and thermosetting agent (b2) as thermosetting components (b), and that the film-like adhesive contains epoxy resin (b1) that is solid at room temperature.

[0087] In the film-type adhesive, the ratio of epoxy resin (b1) content to the total mass of the film-type adhesive is preferably 30 to 70% by mass, more preferably 40 to 65% by mass, and even more preferably 50 to 60% by mass. Having this ratio within this range results in better adhesive properties of the film-type adhesive.

[0088] In composition (III) and the film-like adhesive, the ratio of the content of epoxy resin (b1) that is solid at room temperature (referred to herein as "solid epoxy resin (b1)") to the total content of epoxy resin (b1) is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more, for example, it may be 93% by mass or more and 96% by mass or more. The effect obtained by using solid epoxy resin (b1) is further enhanced when the ratio is above the lower limit. On the other hand, the aforementioned ratio may be 100% by mass or less, or it may be 100% by mass.

[0089] (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.

[0090] 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).

[0091] The hydroxyl group equivalent of the thermosetting agent (b2) is preferably 10 to 120 g / eq, and may be, for example, 40 to 120 g / eq and 80 to 120 g / eq.

[0092] 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.

[0093] In order to improve the heat resistance and adhesive strength of the thermosetting film adhesive and further enhance the reliability of the substrate device, the softening point of the thermosetting agent (b2) is preferably 50 to 110°C, and may be any of 50 to 90°C, 60 to 100°C, and 70 to 110°C.

[0094] In composition (III) and the film-like adhesive, the content of the thermosetting agent (b2) is preferably 20 to 60 parts by mass per 100 parts by mass of the epoxy resin (b1), and may be, for example, 20 to 50 parts by mass, 30 to 60 parts by mass, or 30 to 50 parts by mass. When the content of the thermosetting agent (b2) is above the lower limit, the thermal curing 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.

[0095] In composition (III) and the film-like adhesive, the content of the thermosetting component (b) (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 the binder resin (a). 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-like adhesive and the support sheet or dicing sheet described later.

[0096] <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.

[0097] 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 obtained by using the curing accelerator (c) is increased. 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 increased, and the reliability of the package obtained using the film adhesive is further improved.

[0098] ○Other ingredients Composition (III) and the film-like adhesive may contain, or may not contain, any other components that do not fall under any of the following categories: binder resin (a), thermosetting component (b), or curing accelerator (c). Examples of the other components mentioned above include fillers (d), 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 fillers (d), coupling agents (e), crosslinking agents (f), energy-ray curable resins (g), photopolymerization initiators (h), colorants (i), and general-purpose additives (j), may consist of only one type or two or more types, and if there are two or more types, their combinations and ratios can be arbitrarily selected.

[0099] <Filling material (d)> By using a film-like adhesive containing filler (d), it is possible to reduce the moisture absorption rate and improve the heat dissipation of the cured product, and furthermore, improve the reliability of the package.

[0100] The average particle size of the filler (d) is not particularly limited, but is preferably 10 nm to 5 μm.

[0101] In this specification, unless otherwise specified, the "average particle diameter" means the particle diameter (D 50 ) at the 50% integration value in the particle size distribution curve obtained by the laser diffraction scattering method.

[0102] The filler (d) may be either an organic filler or an inorganic filler, but is preferably an inorganic filler. Preferred inorganic fillers include, for example, powders such as silica, alumina, talc, calcium carbonate, titanium white, red iron oxide, silicon carbide, boron nitride; beads obtained by spheroidizing these inorganic fillers; surface-modified products of these inorganic fillers; single crystal fibers of these inorganic fillers; glass fibers, and the like. Among these, the inorganic filler is preferably silica, alumina or a surface-modified product thereof.

[0103] When the film adhesive contains the filler (d), in the film adhesive, the ratio of the content of the filler (d) to the total mass of the film adhesive is preferably 2% by mass or more, and more preferably 3% by mass or more. By the ratio being at least the lower limit value, the effect obtained by using the filler (d) becomes higher. On the other hand, the filler (d) tends to reduce the cutting speed during plasma dicing of the film adhesive, and this is particularly remarkable when an inorganic filler is used as the filler (d). Therefore, in order to increase the cutting speed during plasma dicing of the film adhesive while obtaining the effect of using the filler (d), it is preferable that the ratio is 10% by mass or less, and more preferably 7% by mass or less.

[0104] In terms of the cutting speed during plasma dicing of the film-like adhesive being higher, it is preferable that the film-like adhesive does not contain the filler (d), or contains the filler (d) and, in the film-like adhesive, the ratio of the content of the filler (d) to the total mass of the film-like adhesive is 5% by mass or less, that is, in the film-like adhesive, the ratio of the content of the filler (d) to the total mass of the film-like adhesive is 0 to 5% by mass. In this case, the ratio may be, for example, either 2 to 5% by mass or 3 to 5% by mass.

[0105] <Coupling agent (e)> The film-like adhesive contains the coupling agent (e), whereby the adhesiveness and the adhesion to the adherend are improved. Further, since the film-like adhesive contains the coupling agent (e), the cured product thereof has improved water resistance without impairing the heat resistance. The coupling agent (e) has a functional group capable of reacting with an inorganic compound or an organic compound.

[0106] The coupling agent (e) is preferably a compound having a functional group capable of reacting with the functional groups of the binder resin (a), the thermosetting component (b), etc., and more preferably a silane coupling agent.

[0107] When using the coupling agent (e), in the composition (III) and the film-like adhesive, the content of the coupling agent (e) 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 with respect to 100 parts by mass of the total content of the binder resin (a) and the thermosetting component (b). When the content of the coupling agent (e) is at least the lower limit value, the effects of using the coupling agent (e), such as the improvement of the dispersibility of the filler (d) in the resin and the improvement of the adhesiveness of the film-like adhesive to the adherend, can be obtained more significantly. When the content of the coupling agent (e) is at most the upper limit value, the generation of outgas is more suppressed.

[0108] <Crosslinking agent (f)> If the binder resin (a), such as the acrylic resin mentioned above, has functional groups such as hydroxyl groups, glycidyl groups, vinyl groups, (meth)acryloyl groups, amino groups, carboxyl groups, and isocyanate groups that can bond with other compounds, the crosslinking agent (f) crosslinks the functional groups in the binder resin (a) with other compounds. In this case, the initial adhesive strength and cohesive strength of the film-like adhesive can be adjusted.

[0109] 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).

[0110] 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 binder resin (a). On the other hand, the content is 0 parts by mass or more. Since the pickability of the film-like adhesive-coated chip 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).

[0111] In this specification, the characteristic of being able to normally pick up an object, such as a chip with a film-like adhesive, from a support sheet or dicing sheet is sometimes referred to as "pickupability."

[0112] <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.

[0113] 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.

[0114] Examples of the acrylate compounds include (meth)acrylates containing a chain-like aliphatic skeleton, (meth)acrylates containing a cyclic aliphatic skeleton, polyalkylene glycol (meth)acrylates, oligoester (meth)acrylates, urethane (meth)acrylate oligomers, epoxy-modified (meth)acrylates, polyether (meth)acrylates other than the aforementioned polyalkylene glycol (meth)acrylates, itaconic acid oligomers, and the like.

[0115] The molecular weight or weight-average molecular weight of the energy ray-curable component (g) is preferably 100 to 30,000, and more preferably 300 to 10,000.

[0116] When using an energy ray-curable component (g), 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).

[0117] <Photopolymerization initiator (h)> The photopolymerization initiator (h) is a component that efficiently promotes the polymerization reaction of the energy ray curable component (g).

[0118] 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, benzyl, dibenzyl, benzophenone, 2,4-diethylthioxanthone, 1,2-diphenylmethane, 2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)propanone, quinone compounds, and the like. Examples of photopolymerization initiators (h) include photosensitizers such as amines.

[0119] 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).

[0120] <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.

[0121] 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.

[0122] <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).

[0123] The content of composition (III) and the general-purpose additive (i) in the film-like adhesive is not particularly limited and can be appropriately selected depending on the type of general-purpose additive (i), for example.

[0124] When composition (III) and the film-like adhesive contain antioxidant (j1), the ratio of 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 chip with the film-like adhesive is further improved. When the ratio is below the upper limit, excessive use of antioxidant (j1) is suppressed.

[0125] 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.

[0126] <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.

[0127] 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.

[0128] 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.

[0129] <<An example of a film-type adhesive>> An example of a preferred film-like adhesive in this embodiment is a film-like adhesive for use in plasma dicing, The aforementioned film-like adhesive contains a binder resin (a) and a thermosetting component (b), The weight loss rate of the aforementioned film-like adhesive when heated at 200°C for 1 hour is 6% by weight or more. The aforementioned film-like adhesive contains either an acrylic resin or a saturated polyester resin, or both, as the binder resin (a). The film-like adhesive contains an epoxy resin (b1) and a thermosetting agent (b2) as the thermosetting component (b), In the aforementioned film-like adhesive, the ratio of the epoxy resin (b1) content to the total mass of the film-like adhesive is 30 to 70% by mass. The aforementioned film-like adhesive contains, as the epoxy resin (b1), which is solid at room temperature. Examples of film-like adhesives include those that do not contain filler (d), or that contain filler (d), and in the film-like adhesive, the ratio of the content of filler (d) to the total mass of the film-like adhesive is 5% by mass or less.

[0130] In such a preferred film-like adhesive, the weight-average molecular weight of the binder resin (a) is preferably 800,000 or less. In such a preferred film-like adhesive, the ratio of the binder resin (a) content to the total mass of the film-like adhesive is preferably 10 to 40% by mass. In such a preferred film-like adhesive, the ratio of the epoxy resin (b1) content, which is solid at room temperature, to the total content of the epoxy resin (b1) is preferably 70% by mass or more. In such a preferred film-like adhesive, the total content of the epoxy resin (b1) and thermosetting agent (b2) is preferably 50 to 800 parts by mass per 100 parts by mass of the binder resin (a). In such a preferred film-like adhesive, the content of the thermosetting agent (b2) is preferably 20 to 60 parts by mass per 100 parts by mass of the epoxy resin (b1). However, these are merely examples of preferred film-like adhesives.

[0131] <<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.

[0132] ◇Film-type adhesive composite sheet A film-like adhesive composite sheet according to one embodiment of the present invention comprises a support sheet and a film-like adhesive provided on one surface of the support sheet, wherein the film-like adhesive is the film-like adhesive according to the above-described embodiment of the present invention. The film-like adhesive composite sheet of this embodiment can be used, for example, as a sheet for cutting a film-like adhesive attached to a chip by plasma irradiation. Finally, as will be described later, the chip with the film-like adhesive obtained after plasma irradiation is pulled away from the support sheet and picked up. By using the film-like adhesive composite sheet of this embodiment, the film-like adhesive can be quickly cut by plasma irradiation.

[0133] 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.

[0134] <<Support Sheet>> Examples of the support sheet include one consisting only of a base material; or one comprising a base material and an adhesive layer provided on one surface of the base material.

[0135] If the support sheet comprises the base material and the adhesive layer, in the film-like adhesive composite sheet, the adhesive layer is positioned between the base material and the film-like adhesive. The adhesive layer is a layer designed to facilitate the pickup of the film-type adhesive semiconductor chip, which will be described later, from the support sheet.

[0136] The base material and the adhesive layer may each consist of one layer (single layer) or two or more layers. If there are multiple layers, these layers may be identical or different, and the combination of these layers is not particularly limited.

[0137] Figure 2 is a schematic cross-sectional view showing an example of a film-like adhesive composite sheet according to this embodiment. In Figures 2 and beyond, components identical to those shown in previously explained figures are denoted by the same reference numerals, and their detailed explanations are omitted.

[0138] The film-like adhesive composite sheet 101 shown in Figure 2 comprises a support sheet 10 and a film-like adhesive 13 provided on one surface 10a of the support sheet 10. The support sheet 10 comprises a base material 11 and an adhesive layer 12 provided on one surface 11a of the base material 11. In the film-like adhesive composite sheet 101, the adhesive layer 12 is positioned between the substrate 11 and the film-like adhesive 13. The film-like adhesive 13 is a film-like adhesive according to the above-described embodiment of the present invention.

[0139] The film-like adhesive composite sheet 101 further includes a release film 15 on one side 13a of the film-like adhesive 13. In the film-like adhesive composite sheet 101, the release film 15 has any configuration. The other side (sometimes referred to as the "second side" in this specification) 13b of the film-like adhesive 13 is bonded to the adhesive layer 12 in the support sheet 10.

[0140] The film-like adhesive composite sheet 101 is used by attaching a wafer to the first surface 13a of the film-like adhesive 13 after the release film 15 has been removed.

[0141] The film-like adhesive composite sheet of this embodiment is not limited to that shown in Figure 2, and some components of this film-like adhesive composite sheet may be modified, deleted, or added without departing from the spirit of the present invention.

[0142] For example, the film-like adhesive composite sheet of this embodiment does not need to have an adhesive layer. An example of such a film-like adhesive composite sheet is the film-like adhesive composite sheet 101 shown in Figure 2, in which the adhesive layer 12 is omitted and the second surface 13b of the film-like adhesive 13 is bonded to the substrate 11.

[0143] 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 the categories of base material, adhesive layer, film-like adhesive, or release film. The aforementioned other layers can be arbitrarily selected depending on the purpose and are not particularly limited.

[0144] In the film-like adhesive composite sheet of this embodiment, it is preferable that the support sheet consists only of a substrate and that the film-like adhesive is provided in direct contact with the substrate. When a support sheet consisting only of a substrate is used, the film-like adhesive composite sheet can be manufactured at a low cost.

[0145] <Base material> The substrate may be in the form of a sheet or a film, and may be one of known types. Examples of constituent materials for the base material include various resins. The resins that make up the base material may be of one type or two or more types, and if there are two or more types, their combination and ratio can be arbitrarily selected.

[0146] 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); polyesters such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyethylene isophthalate, and polyethylene-2,6-naphthalenedicarboxylate; and polyimides. 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.

[0147] 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.

[0148] 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.

[0149] The thickness of the substrate is preferably 50 to 300 μm, and more preferably 60 to 140 μm. Having the substrate thickness within this range improves the flexibility of the film-like adhesive composite sheet and its suitability for adhesion to wafers.

[0150] 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.

[0151] <Adhesive layer> The adhesive layer is in the form of a sheet or film and contains an adhesive. Examples of the adhesive include adhesive resins such as acrylic resin, urethane resin, rubber resin, silicone resin, epoxy resin, polyvinyl ether, polycarbonate, and ester resin.

[0152] The thickness of the adhesive layer is not particularly limited, but is preferably 1 to 100 μm.

[0153] The adhesive layer may be either energy-ray curable or non-energy-ray curable. If the adhesive layer is energy-ray curable, the semiconductor chip with the film-like adhesive can be picked up more easily by curing the adhesive layer with energy rays before picking it up from the support sheet.

[0154] The adhesive layer can be formed using an adhesive composition containing an adhesive. For example, the adhesive composition can be applied to the surface on which the adhesive layer is to be formed, and then dried as necessary to form the adhesive layer in the desired location. The coating and drying of the adhesive composition can be carried out, for example, in the same manner as in the coating and drying of the adhesive composition described above.

[0155] <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.

[0156] <<Manufacturing Method for Film-Like Adhesive Composite Sheets>> 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.

[0157] For example, when laminating a film-like adhesive onto a substrate, the adhesive composition is applied to a release film and dried as needed 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. When manufacturing a film-like adhesive composite sheet with an adhesive layer, for example, an adhesive layer is formed on a release film in the same manner as in the case of the film-like adhesive described above, and a support sheet is made by bonding the exposed surface of this adhesive layer to one side of the substrate. Separately, a film-like adhesive is made on a release film in the same manner as described above. Then, the release film is removed from the adhesive layer in the support sheet, and the exposed surface of the adhesive layer resulting from this is bonded to the exposed surface of the film-like adhesive on the release film to obtain a film-like adhesive composite sheet with a release film.

[0158] ◇Manufacturing method for chips with film-like adhesive (Method of using film-like adhesive and film-like adhesive composite sheet) The aforementioned film-like adhesive and film-like adhesive composite sheet can be used to manufacture a film-like adhesive coated chip comprising a chip and a film-like adhesive provided on one side of the chip, and the resulting film-like adhesive coated chip can further be used to manufacture substrate devices. By using the aforementioned film-like adhesive or film-like adhesive composite sheet, the film-like adhesive can be quickly cut by plasma dicing during the manufacturing process of chips coated with the film-like adhesive.

[0159] In a method for manufacturing a chip with a film-like adhesive according to one embodiment of the present invention, a dicing die bonding sheet or a film-like adhesive composite sheet is used, comprising the film-like adhesive and a dicing sheet provided on one side of the film-like adhesive. The side of the film-like adhesive in the dicing die bonding sheet or the film-like adhesive composite sheet that is opposite to the side of the dicing sheet or support sheet (in this specification, in either case, may be referred to as the "first side") is attached to one side of the wafer. Plasma is irradiated onto the wafer and the film-like adhesive from outside the wafer side on the dicing sheet or support sheet to divide the wafer and produce the chip, and the film-like adhesive is cut to obtain the film-like adhesive chip with the cut film-like adhesive.

[0160] The method for manufacturing a film-like adhesive chip according to this embodiment may be the same as the conventional method for manufacturing a film-like adhesive chip, except that the film-like adhesive or film-like adhesive composite sheet of this embodiment described above is used instead of the conventional film-like adhesive or film-like adhesive composite sheet.

[0161] As a method for manufacturing a film-type adhesive-coated chip according to this embodiment, the method for manufacturing a film-type adhesive-coated semiconductor chip, where the wafer is a semiconductor wafer and the chip is a semiconductor chip, will be described below with reference to the drawings.

[0162] <<Manufacturing method for semiconductor chips with film-like adhesive>> Figure 3 is a schematic cross-sectional view illustrating the manufacturing method of a semiconductor chip with a film-like adhesive according to this embodiment. Here, the manufacturing method using the film-like adhesive composite sheet 101 shown in Figure 2 will be described.

[0163] In the above manufacturing method, first, as shown in Figure 3(a), the side 13a of the film-like adhesive 13 in the film-like adhesive composite sheet 101 that is opposite to the side of the support sheet 10 is attached to the back surface 9b of the semiconductor wafer 9. This obtains a semiconductor wafer 901 with a film-like adhesive composite sheet.

[0164] The attachment of the film-like adhesive composite sheet 101 (film-like adhesive 13) to the semiconductor wafer 9 can be carried out by known methods, for example, at room temperature (e.g., room temperature) or under heated conditions.

[0165] In the above manufacturing method, plasma is then irradiated onto the semiconductor wafer 9 and the film-like adhesive 13 from outside the semiconductor wafer 9 side on the support sheet 10 in the semiconductor wafer 901 with the film-like adhesive composite sheet, thereby dividing the semiconductor wafer 9 to produce a semiconductor chip 90 and cutting the film-like adhesive 13. Through this plasma dicing, a semiconductor chip 91 with a film-like adhesive is obtained, comprising the semiconductor chip 90 and the cut film-like adhesive 130 provided on the back surface 90b of the semiconductor chip 90, as shown in Figure 3(b). At this time, the film-like adhesive 13 according to the above-described embodiment is quickly cut by plasma dicing.

[0166] In this specification, not only in the case of the manufacturing method described above, "pre-cut film-like adhesive" may be simply referred to as "film-like adhesive."

[0167] These multiple semiconductor chips 91 with film-like adhesive are aligned and held on one surface 10a of the support sheet 10, and together with the support sheet 10, they constitute a semiconductor chip group holder 902 with film-like adhesive. The first surface 130a and the second surface 130b of the cut film-like adhesive 130 are derived from the first surface 13a and the second surface 13b of the film-like adhesive 13 before cutting, respectively. 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, when the semiconductor wafer 9 is divided.

[0168] The process gas used to generate the irradiated plasma may be any known gas, such as oxygen (O2) gas or sulfur hexafluoride (SF6) gas. Among these, oxygen gas is preferred as the process gas because it allows for particularly fast cutting of film-like adhesives by plasma dicing.

[0169] When cutting the film-like adhesive 13 by irradiating it with plasma and dry etching it, the plasma irradiation conditions are not particularly limited as long as the film-like adhesive 13 can be sufficiently cut, and can be appropriately adjusted depending on the type of film-like adhesive 13, the type of process gas used to generate the plasma, etc. For example, when generating plasma using oxygen (O2) gas, the oxygen gas flow rate may be 50-300 mL, the RF (Radio Frequency; the same applies hereafter) output may be 300-500 W, and the RF duration may be 2-5 min. However, these conditions are just examples.

[0170] The splitting of the semiconductor wafer 9 by plasma irradiation and the cutting of the film-like adhesive 13 may be performed continuously using the same operation, or they may be performed continuously under different conditions. When performing the operations continuously under different conditions, for example, when splitting the semiconductor wafer 9, the plasma may be irradiated onto the semiconductor wafer 9 under conditions suitable for this purpose, and then, when cutting the film-like adhesive 13, the plasma may be irradiated onto the film-like adhesive 13 under different conditions than those used for splitting the semiconductor wafer 9.

[0171] All semiconductor chips 91 with film adhesive in the semiconductor chip group holder 902 are held on the first surface 10a of the support sheet 10 by the second surface 130b of the cut film adhesive 130.

[0172] In the above manufacturing method, prior to plasma irradiation, a patterned mask is laminated onto the circuit surface 9a of the semiconductor wafer 9 in the semiconductor wafer 901 with a film-like adhesive composite sheet, in order to produce a semiconductor chip 90 of the desired size and shape. Then, by irradiating the semiconductor wafer 9 on which the mask is laminated with plasma from the mask side, the semiconductor wafer 9 is divided and the film-like adhesive 13 is cut. After that, the mask laminated on the semiconductor chip 90 can be removed by known methods such as using adhesive tape.

[0173] In the semiconductor chip group holder 902 with film adhesive, as shown in Figure 3(c), the film adhesive semiconductor chip 91 can be picked up by using a separation means 5 such as a vacuum collet to separate it from the support sheet 10 in the direction of arrow P. At this time, delamination occurs between the second surface 130b of the cut film adhesive 130 in the film adhesive semiconductor chip 91 and the first surface 10a of the support sheet 10. In this embodiment, if necessary, the support sheet 10 may be expanded in a direction parallel to its first surface 10a to increase the distance between adjacent semiconductor chips 91 with film adhesive before picking up the semiconductor chips 91 with film adhesive.

[0174] Up to this point, a method for manufacturing a semiconductor chip with a film-like adhesive using a film-like adhesive composite sheet has been described. However, in this embodiment, the dicing die bonding sheet may be used instead of the film-like adhesive composite sheet. In that case, for example, a dicing die bonding sheet can be used, which has a dicing sheet instead of a support sheet in the film-like adhesive composite sheet 101 shown in Figure 2. As a dicing sheet, one can be used that has the same configuration as the support sheet 10 in Figure 2, comprising a base material and an adhesive layer provided on one surface of the base material. In such a dicing die bonding sheet, the adhesive layer is positioned between the base material and the film-like adhesive.

[0175] When the dicing die bonding sheet is used, instead of the semiconductor wafer 901 with a film-like adhesive composite sheet shown in Figure 3(a), a semiconductor wafer with a dicing die bonding sheet is manufactured in which the back surface 9b of the semiconductor wafer 9 is attached to the side 13a of the film-like adhesive 13 in the dicing die bonding sheet that is opposite to the side of the dicing sheet. By using this in the same way as the semiconductor wafer 901 with a film-like adhesive composite sheet, a semiconductor chip 91 with a film-like adhesive similar to the one described above can be manufactured and picked up from the dicing sheet.

[0176] ◇Manufacturing method for substrate devices (Method of using film-type adhesive-coated chips) A substrate device can be manufactured using the film-like adhesive-coated chip obtained by the above manufacturing method. The substrate device can be manufactured by known methods, except for the use of the aforementioned film-like adhesive-coated chip. For example, a chip with a film-like adhesive attached is picked up and bonded to a circuit board using the film-like adhesive within it. Then, the film-like adhesive is heat-cured to fix the chip to the circuit board, thereby mounting the chip to the circuit board. The film-like adhesive may also be heat-cured simultaneously by the heating that occurs when the chip is sealed with resin on the circuit board. Furthermore, by adding other processes as needed, the desired circuit board device can be manufactured. [Examples]

[0177] 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.

[0178] The full names of the resin manufacturing raw materials, which are abbreviated in this example and comparative example, are shown below. MA: Methyl acrylate BA: n-butyl acrylate GMA: Glycidyl methacrylate HEA: 2-hydroxyethyl acrylate

[0179] <<Raw materials for manufacturing adhesive compositions>> The raw materials used in the manufacture of the adhesive composition are listed below. [Binder resin (a)] (a)-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 -28.1°C). (a)-2: Acrylic resin obtained by copolymerizing MA (85 parts by mass) and HEA (15 parts by mass) (weight-average molecular weight 400,000, glass transition temperature 6°C). (a)-3: 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 -6°C). (a)-4: Amorphous saturated polyester resin (Byron 220, manufactured by Toyobo Co., Ltd., weight-average molecular weight 35,000, number-average molecular weight 3,000, glass transition temperature 53°C) [Epoxy resin (b1)] (b1)-1: A dicyclopentadiene-type epoxy resin that is solid at room temperature (DIC Corporation's "HP7200HH", softening point 88-98°C, epoxy equivalent 274-285 g / eq) (b1)-2: Liquid bisphenol F type epoxy resin at room temperature (Mitsubishi Chemical Corporation's "YL983U", epoxy equivalent 165-175 g / eq) [Thermosetting agent (b2)] (b2)-1: o-cresol-type novolac resin (DIC Corporation's "Phenolite® KA-1160", hydroxyl group equivalent 117 g / eq, softening point 80°C) [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)

[0180] [Example 1] <<Manufacturing of film-type adhesives>> <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.

[0181] <Manufacturing of film-type adhesives> A release film (second release film, Lintec Corporation's "SP-PET38 2150", 38 μm thick) made of polyethylene terephthalate film with one side treated with silicone release 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-PET38 1031", 38 μm thick) was bonded to the exposed surface of the obtained film-like adhesive to produce a film-like adhesive with release films on both sides.

[0182] <<Evaluation of film-type adhesives>> <Measurement of weight loss rate ΔW1 of film-like adhesive> A 5g piece was cut from the film-like adhesive obtained above, and this was designated as the first test specimen. Using a TG-DTA simultaneous measurement device (Shimadzu Corporation "DTG-60"), the first test specimen was heated in an air atmosphere from 40°C to 200°C at a heating rate of 10°C / min, and then heated at 200°C for 1 hour to obtain a heated sample. The weight loss rate ΔW1 of the film-like adhesive was then calculated from the weight of the film-like adhesive before heating (W0) and the weight of the heated film-like adhesive (W1) according to formula (i) above. The results are shown in the table.

[0183] <Measurement of cutting speed of film-type adhesives> The cutting speed of the film-like adhesive was measured using the method described earlier with reference to Figure 1. Specifically, a rectangular piece was cut from the film-like adhesive obtained above. On this piece, the second release film was removed, and a 10 mm wide, strip-shaped adhesive tape mainly composed of polyimide (Teraoka Seisakusho Co., Ltd.'s "Kapton® Adhesive Tape 650S #25", 50 μm thick) was applied to the exposed surface of the film-like adhesive, in a strip-shaped region parallel to one pair of opposing sides and connecting the other pair of opposing sides, thereby forming a strip-shaped mask on the exposed surface of the film-like adhesive and thus producing a second test specimen.

[0184] Next, a dry etching apparatus (Samco RIE apparatus) was used as the plasma irradiation device, and the pressure was reduced to 20 Pa using a Pfeiffer Pascal 2015 C2 dual-stage rotary vane vacuum pump. Under this reduced pressure environment, the second test specimen was irradiated with plasma from the side with the adhesive tape. At this time, the plasma was irradiated under the conditions of RF (Radio Frequency) output of 400 W, RF time of 3 min, and oxygen gas flow rate of 100 mL. This etched the areas of the film-like adhesive that were not covered (not masked) by the adhesive tape.

[0185] The second test specimen, after plasma irradiation (etching), was removed from the plasma irradiation device, and a laser microscope (Keyence "VK-9700") was used to measure the thickness of the adhesive tape application area on the removed second test specimen (in other words, the total thickness of the first release film, the non-plasma-irradiated area of ​​the film-like adhesive, and the adhesive tape, as shown in Figure 1, T 60 ) and the thickness of the non-adhered portion of the adhesive tape (in other words, the total thickness of the first release film and the plasma-irradiated portion of the film-like adhesive, T in Figure 1) 61The thickness of the adhesive tape was measured. Furthermore, a second test specimen was prepared separately, and under the same conditions, only the adhesive tape was irradiated with plasma P, and then the thickness of the adhesive tape (T7 in Figure 1) was measured. From these measurements, the height of the step difference (etching distance L) between the first surface of the original film-like adhesive and the surface of the etched area of ​​the film-like adhesive was calculated using the method described with reference to Figure 1. The thickness of the adhesive tape after irradiation with plasma P was 49.8 μm.

[0186] Furthermore, the etching rate was calculated from the calculated etching distance L and the plasma irradiation time (etching time), and this was adopted as the cutting speed (μm / min) of the film-like adhesive. The cutting speed was then evaluated according to the following criteria. These results, along with the etching distance L, are shown in Table 1. [Evaluation Criteria] A: The cutting speed of the film-like adhesive is 1 μm / min or more, and is particularly fast. B: The cutting speed of the film-like adhesive is 0.1 μm / min or more and less than 1 μm / min, which is fast. C: The cutting speed of the film-like adhesive is less than 0.1 μm / min, which is slow, or the film-like adhesive cannot be cut.

[0187] <Evaluation of film-forming properties of film-like adhesives> During the manufacturing of the above-mentioned film-like adhesive, the film-like adhesive on the second release film before the first release film was applied was visually observed. Focusing on the fact that the film-forming ability of the film-like adhesive is most reflected at the edges of the adhesive, the film-forming ability of the film-like adhesive was evaluated according to the following criteria based on the presence or absence of dripping at the edges of the adhesive. The results are shown in Table 1. [Evaluation Criteria] A: No dripping was observed at the edges of the film-like adhesive, indicating good film-forming properties. B: Dripping was observed at the edges of the film-like adhesive, indicating poor film formation.

[0188] <Overall evaluation of film-type adhesives> A film-like adhesive that received an A rating for both its film-forming ability and cutting speed was given an overall rating of A. A film-forming adhesive that received an A rating for film-forming ability and a B rating for cutting speed was given an overall rating of B. At a minimum, film-forming adhesives with a film-forming ability rating of B or a cutting speed rating of C were given an overall rating of C. These results are shown in Table 1.

[0189] <<Manufacturing and Evaluation of Film-Type Adhesives>> [Examples 2-5, Comparative Examples 1-2] The film adhesive was manufactured in the same manner as in Example 1, except that the type and amount of components in the adhesive composition were changed, or both, so that the types and amounts of components in the film adhesive were as shown in Table 1. In Table 1, a "-" in the column for the components of the film-type adhesive means that the film-type adhesive does not contain that component. Furthermore, these film-like adhesives were evaluated using the same method as in Example 1. The results are shown in Table 1.

[0190] [Table 1]

[0191] As is clear from the results above, in Examples 1 to 5, the cutting speed when cutting the film-like adhesive by plasma irradiation was 0.13 μm / min or higher, which was fast. In Examples 1 to 5, the weight loss rate ΔW1 of the film-like adhesive was 6.3% by weight or more.

[0192] In Examples 1-5, the weight-average molecular weight of the binder resin (a) contained in the film-like adhesive was 800,000 or less, and the film-like adhesives in Examples 1-4 contained acrylic resin as the binder resin (a). In particular, in Examples 2-4, where the weight-average molecular weight of the acrylic resin was 400,000 and the glass transition temperature was -6°C or higher, the etching distance L was clearly larger and the cutting speed of the film-like adhesive was significantly faster than in Example 1, where the weight-average molecular weight of the acrylic resin was 800,000 and the glass transition temperature was -28.1°C.

[0193] The film-like adhesives of Examples 3 and 4 differ from each other only in the presence or absence of filler (d). However, Example 3, in which the film-like adhesive did not contain filler (d), had a significantly larger etching distance L and a faster cutting speed than Example 4, in which the film-like adhesive did contain filler (d).

[0194] Among Examples 1-5, Examples 2-3, in particular, showed a significantly larger etching distance L and a significantly faster cutting speed of the film-like adhesive. The film-like adhesives in Examples 2-3 contained a relatively small acrylic resin with a weight-average molecular weight of 400,000 and did not contain filler (d).

[0195] From a comparison of Examples 1-3 and Example 5, no superiority or inferiority in suitability as binder resin (a) was observed between acrylic resin and saturated polyester resin.

[0196] In contrast, in Comparative Example 1, the film-like adhesive could not be cut by plasma irradiation. In Comparative Example 1, the weight loss rate ΔW1 of the film-like adhesive was 0% by weight.

[0197] In Comparative Example 2, the film-like adhesive could be cut by plasma irradiation, but the cutting speed of the film-like adhesive was slow. In Comparative Example 2, the weight loss rate ΔW1 of the film-like adhesive was 4% by weight. [Industrial applicability]

[0198] This invention can be used in the manufacture of substrate devices. [Explanation of Symbols]

[0199] 10...Support sheet, 10a...One side of the support sheet (first side) 101...Film-type adhesive composite sheet 11...Substrate, 11a...One side of the substrate 12. Adhesive layer 13...Film-like adhesive, 13a...One side of the film-like adhesive, 13b...The other side of the film-like adhesive 130... Pre-cut film-type adhesive 9... Semiconductor wafer, 9b... Back side of semiconductor wafer 90... Semiconductor chip, 90b... Back side of semiconductor chip 901... Semiconductor wafer with film-like adhesive composite sheet 91... Semiconductor chip with film-type adhesive

Claims

1. A film-like adhesive for use in plasma dicing, The aforementioned film-like adhesive contains a binder resin (a) and a thermosetting component (b), A film-like adhesive in which the weight loss rate when the film-like adhesive is heated at 200°C for 1 hour is 6% by weight or more.

2. The film-like adhesive according to claim 1, wherein the weight-average molecular weight of the binder resin (a) is 850,000 or less.

3. The film-like adhesive according to claim 1 or 2, wherein the film-like adhesive does not contain filler (d), or contains filler (d), and the ratio of the content of filler (d) to the total mass of the film-like adhesive is 5% by mass or less.

4. The film-like adhesive contains an epoxy resin (b1) and a thermosetting agent (b2) as the thermosetting component (b), The film-like adhesive according to claim 1 or 2, wherein the film-like adhesive contains an epoxy resin (b1) that is solid at room temperature.

5. The device comprises a support sheet and a film-like adhesive provided on one surface of the support sheet, A film-like adhesive composite sheet wherein the film-like adhesive is the film-like adhesive described in claim 1.

6. The film-like adhesive composite sheet according to claim 5, wherein the support sheet consists only of a base material.

7. A method for manufacturing a chip with a film-like adhesive, comprising a chip and a film-like adhesive provided on one side of the chip, In the above manufacturing method, a dicing die bonding sheet comprising the film-like adhesive described in claim 1 and a dicing sheet provided on one side of the film-like adhesive, or a film-like adhesive composite sheet described in claim 5 is used. The side of the film-like adhesive in the dicing die bonding sheet or the film-like adhesive composite sheet that is opposite to the side of the dicing sheet or support sheet is attached to one side of the wafer. A method for manufacturing a chip with a film-like adhesive, comprising: irradiating the wafer and the film-like adhesive with plasma from outside the wafer side on the dicing sheet or support sheet to divide the wafer and produce the chip, and cutting the film-like adhesive to obtain the chip with the cut film-like adhesive.

Images