Dicing die-bonding film

Abstract

The cutting chip bonding film of the present application is provided with: a cutting tape in which an adhesive layer is layered on a base material layer, and a chip bonding layer layered on the adhesive layer of the aforementioned cutting tape, the aforementioned adhesive layer containing a photopolymerization initiator, in a molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the ratio of the weight average molecular weight Mw of the peak appearing on the highest molecular weight side to the number average molecular weight Mn of the peak appearing on the highest molecular weight side, that is, the polydispersity Mw / Mn is 1.3 or more.

Description

Technical Field

[0001] This invention relates to dicing chip bonding films. Background Technology

[0002] Previously, it was known that in the manufacture of semiconductor devices, diced chip bonding films were used to obtain semiconductor chips for chip bonding (e.g., Patent Document 1).

[0003] The aforementioned chip bonding film comprises a cutting strip having an adhesive layer laminated on a substrate layer, and a chip bonding layer peelably laminated on the adhesive layer of the cutting strip.

[0004] Furthermore, as a method for obtaining a semiconductor chip (Die) for chip bonding using the aforementioned dicing chip bonding film, a method comprising the following steps is known: a half-dicing step of forming grooves on a semiconductor wafer to be processed into a chip (Die) by dicing; a back-side grinding step of thinning the semiconductor wafer after the half-dicing step by grinding; a mounting step of attaching one side of the semiconductor wafer after the back-side grinding step (e.g., the side opposite to the circuit surface) to a chip bonding layer and fixing the semiconductor wafer to a dicing tape; an expansion step of increasing the spacing between the half-diced semiconductor chips; a cut-holding step of maintaining the spacing between the semiconductor chips; and a pick-up step of peeling the chip bonding layer from the adhesive layer and removing the semiconductor chip with the chip bonding layer attached.

[0005] Furthermore, in the aforementioned pick-up process, the semiconductor chip (hereinafter also referred to as the semiconductor chip with chip bonding layer) that is taken out in a state of being attached to the chip bonding layer is bonded to the wiring substrate that is the object to be bonded.

[0006] Furthermore, the aforementioned adhesive layer typically comprises: a resin such as a (meth)acrylic resin, a crosslinking agent that reacts with the resin to polymerize the resins together, and a photopolymerization initiator that generates an active species capable of chain polymerization of the resins when exposed to radiation such as ultraviolet light (e.g., Patent Document 2). In such an adhesive layer, the curing reaction occurs when exposed to radiation such as ultraviolet light, thereby reducing the peel force between the adhesive layer and the aforementioned chip bonding layer, thus making it easier to peel the adhesive layer from the aforementioned chip bonding layer.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 2019-9203

[0010] Patent Document 2: Japanese Patent Application Publication No. 2019-67996 Summary of the Invention

[0011] The problem the invention aims to solve

[0012] However, as described above, although the aforementioned chip bonding layer is peeled (separated) from the aforementioned adhesive layer in the aforementioned pick-up process, the aforementioned chip bonding layer and the aforementioned adhesive layer were in contact before the aforementioned pick-up process.

[0013] Therefore, as described above, when the aforementioned photopolymerization initiator is included in the aforementioned adhesive layer, the aforementioned photopolymerization initiator may sometimes transfer from the aforementioned adhesive layer to the aforementioned chip bonding layer.

[0014] Thus, when the aforementioned photopolymerization initiator is transferred from the aforementioned adhesive layer to the aforementioned chip bonding layer, it sometimes fails to meet the characteristics required by the aforementioned adhesive layer or the aforementioned chip bonding layer, and is therefore not preferred.

[0015] However, it is difficult to say that sufficient research has been conducted on suppressing the transfer of the aforementioned photopolymerization initiator from the aforementioned adhesive layer to the aforementioned chip bonding layer.

[0016] Therefore, the objective of this invention is to provide a die bonding film capable of relatively suppressing the transfer of photopolymerization initiator from the adhesive layer to the die bonding layer.

[0017] Solution for solving the problem

[0018] The chip bonding film of the present invention comprises:

[0019] A cut strip with an adhesive layer laminated on top of the substrate layer, and

[0020] A chip bonding layer is stacked on the adhesive layer of the aforementioned dicing tape.

[0021] The aforementioned adhesive layer comprises an adhesive and a photopolymerization initiator.

[0022] In the molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the ratio of the weight average molecular weight Mw of the peak appearing on the highest molecular weight side to the number average molecular weight Mn of the peak appearing on the highest molecular weight side, i.e., the polydispersity Mw / Mn, is 1.3 or higher.

[0023] In the aforementioned chip bonding film...

[0024] In the molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the peak molecular weight value of the peak appearing on the highest molecular weight side is preferably 33,000 or less.

[0025] In the aforementioned chip bonding film...

[0026] The aforementioned adhesive layer before curing preferably contains less than 32% by mass of sol component.

[0027] In the aforementioned chip bonding film...

[0028] After the aforementioned adhesive layer has cured, the peel force of the aforementioned chip bonding layer relative to the aforementioned adhesive layer is preferably less than 0.18 N / 20 mm. Attached Figure Description

[0029] Figure 1 This is a cross-sectional view illustrating the structure of a die-cutting bonding film according to one embodiment of the present invention.

[0030] Figure 2A It is a cross-sectional view schematically illustrating the half-cutting process in the manufacturing method of semiconductor integrated circuits.

[0031] Figure 2B It is a cross-sectional view schematically illustrating the half-cutting process in the manufacturing method of semiconductor integrated circuits.

[0032] Figure 2C This is a cross-sectional view schematically illustrating the back-side grinding process in the manufacturing method of semiconductor integrated circuits.

[0033] Figure 2D This is a cross-sectional view schematically illustrating the back-side grinding process in the manufacturing method of semiconductor integrated circuits.

[0034] Figure 3A It is a cross-sectional view schematically illustrating the mounting process in the manufacturing method of semiconductor integrated circuits.

[0035] Figure 3B It is a cross-sectional view schematically illustrating the mounting process in the manufacturing method of semiconductor integrated circuits.

[0036] Figure 4A This is a cross-sectional view schematically illustrating the low-temperature extension process in the manufacturing method of semiconductor integrated circuits.

[0037] Figure 4B This is a cross-sectional view schematically illustrating the low-temperature extension process in the manufacturing method of semiconductor integrated circuits.

[0038] Figure 4C This is a cross-sectional view schematically illustrating the low-temperature extension process in the manufacturing method of semiconductor integrated circuits.

[0039] Figure 5A This is a cross-sectional view schematically illustrating the extended process at room temperature in the manufacturing method of semiconductor integrated circuits.

[0040] Figure 5B This is a cross-sectional view schematically illustrating the extended process at room temperature in the manufacturing method of semiconductor integrated circuits.

[0041] Figure 6 This is a cross-sectional view schematically illustrating the cut-holding process in a semiconductor integrated circuit manufacturing method.

[0042] Figure 7 This is a cross-sectional view schematically illustrating the pick-up process in a semiconductor integrated circuit manufacturing method.

[0043] Explanation of reference numerals in the attached figures

[0044] 1. Substrate layer

[0045] 2 Adhesive layer

[0046] 3. Chip bonding layer

[0047] 10 Cutting strip

[0048] 20 Cut chip bonding film

[0049] G Backside Grinding Belt

[0050] H retainer

[0051] J Adsorption clamp

[0052] P pin components

[0053] R Cutting Ring

[0054] T-shaped wafer processing strip

[0055] U-shaped lifting component

[0056] W Semiconductor Wafer Detailed Implementation

[0057] The following describes one embodiment of the present invention.

[0058] [Cutting chip bonding film]

[0059] like Figure 1 As shown, the chip bonding film 20 of this embodiment includes a cutting strip 10 on a substrate layer 1 having an adhesive layer 2 stacked thereon, and a chip bonding layer 3 stacked on the adhesive layer 2 of the cutting strip 10.

[0060] In the chip bonding film 20, a semiconductor wafer is attached to the chip bonding layer 3.

[0061] In the dicing of a semiconductor wafer using the dicing chip bonding film 20, the chip bonding layer 3 is also diced along with the semiconductor wafer. The chip bonding layer 3 is diced to a size comparable to the dimensions of multiple monolithically mounted semiconductor chips. Thus, a semiconductor chip with the chip bonding layer 3 can be obtained.

[0062] In the dicing and bonding film 20 of this embodiment, the adhesive layer 2 comprises an adhesive and a photopolymerization initiator. The adhesive layer 2 holds the semiconductor wafer, which is to be monolithically formed into a semiconductor chip, by bonding.

[0063] As an example of the aforementioned adhesive, an adhesive that can reduce the adhesive force through external action during the use of the cutting strip 10 can be listed (hereinafter also referred to as an adhesive-reducing adhesive).

[0064] When using an adhesive-reducing adhesive as a binder, during the use of the cutting strip 10, the adhesive layer 2 can be used separately in a state showing high adhesive strength (hereinafter referred to as high adhesive state) and a state showing low adhesive strength (hereinafter referred to as low adhesive state).

[0065] For example, when a semiconductor wafer attached to a cutting strip 10 is cut, a high-adhesion state is utilized to prevent multiple semiconductor chips monolithized by cutting the semiconductor wafer from floating or peeling off from the adhesive layer 2.

[0066] In contrast, after the semiconductor wafer is cut, a low-adhesion state is used to pick up multiple monolithic semiconductor chips so that multiple semiconductor chips can be easily picked up from the adhesive layer 2.

[0067] Examples of adhesives that reduce adhesion include, for instance, adhesives that can be cured by radiation during the use of the cutting strip 10 (hereinafter referred to as radiation-curing adhesives).

[0068] Examples of radiation-curing adhesives include those that cure by irradiation with electron beams, ultraviolet light, alpha rays, beta rays, gamma rays, or X-rays. Among these, adhesives that cure by irradiation with ultraviolet light (UV-curing adhesives) are preferred.

[0069] Examples of radiation-curing adhesives include additive-type radiation-curing adhesives, which contain a base polymer as the main component, radiation-polymerizable monomer components with functional groups such as carbon-carbon double bonds that have radiation-polymerizable properties, and radiation-polymerizable oligomer components.

[0070] As the aforementioned base polymer, acrylic polymers are preferred.

[0071] Examples of the aforementioned acrylic polymers include acrylic polymers comprising monomer units derived from (meth)acrylates. Examples of (meth)acrylates include, for instance, alkyl (meth)acrylates, cycloalkyl (meth)acrylates, and aryl (meth)acrylates.

[0072] As the aforementioned acrylic polymers, preferred materials include, for example, 2-hydroxyethyl acrylate (HEA), ethyl acrylate (EA), butyl acrylate (BA), 2-ethylhexyl acrylate (2EHA), isononyl acrylate (INA), lauryl acrylate (LA), 4-acryloylmorpholine (AMCO), and 2-isocyanate ethyl-methacrylate (MOI).

[0073] These acrylic polymers can be used in combination, either using only one type or in combination of two or more.

[0074] Examples of the aforementioned radiation-polymerizable monomer components include: urethane (meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxy penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and 1,4-butanediol di(meth)acrylate.

[0075] Examples of the aforementioned radiation-polymerizable oligomers include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based oligomers.

[0076] The proportions of the aforementioned radiation-curing adhesive components, including the aforementioned radiation-polymerizing monomers and the aforementioned radiation-polymerizing oligomers, can be selected within a range that appropriately reduces the adhesion of the adhesive layer 2.

[0077] Examples of photopolymerization initiators included in the adhesive layer 2 include α-keto alcohol compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, thioxanone compounds, camphorquinone, haloketones, acylphosphine oxides, and acylphosphonates.

[0078] As the aforementioned photopolymerization initiator, a photoradical initiator is preferred. Photoradical initiators generate free radicals by irradiation with active energy rays (e.g., electron beams, ultraviolet rays, alpha rays, beta rays, gamma rays, or X-rays).

[0079] Examples of photoradical initiators include 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropanoyl)benzoyl)phenyl)-2-methylpropane-1-one (commercially available as Omnirad 127 manufactured by IGM Resins), 2,2-dimethoxy-1,2-diphenylethane-1-one (commercially available as Omnirad 651 manufactured by IGM Resins), 1-hydroxy-cyclohexylphenyl one (commercially available as Omnirad 184 manufactured by IGM Resins), and 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propane-1-one (commercially available as Omnirad 184 manufactured by IGM Resins). 2959), 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1 (as a commercially available product, Omnirad 369E manufactured by IGM Resins), bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide (as a commercially available product, Omnirad 819 manufactured by IGM Resins), acetone-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]-1-(O-acetyl oxime) (as a commercially available product, OXE02 manufactured by Irgacure), etc.

[0080] Among these, 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropionyl)benzoyl)phenyl)-2-methylpropane-1-one (as a commercially available product, Omnirad127 manufactured by IGM Resins) is preferred.

[0081] The adhesive layer 2 preferably contains 0.1 parts by weight or more and 10 parts by weight of the aforementioned photopolymerization initiator.

[0082] In the chip bonding film 20 of this embodiment, the ratio of the weight average molecular weight Mw of the peak appearing on the highest molecular weight side to the number average molecular weight Mn of the peak appearing on the highest molecular weight side, i.e., the polydispersity Mw / Mn, is 1.3 or more in the molecular weight distribution curve obtained by measuring the adhesive layer 2 before curing using GPC (gel permeation chromatography).

[0083] By making the polydispersity Mw / Mn greater than 1.3, low molecular weight components are appropriately mixed among the high molecular weight components in the adhesive layer 2, thereby relatively suppressing the transfer of the aforementioned photopolymerization initiator from the adhesive layer 2 to the chip bonding layer 3.

[0084] Furthermore, the aforementioned polydispersity Mw / Mn is preferably 2.0 or higher. By setting the aforementioned polydispersity Mw / Mn to 2.0 or higher, the transfer of the aforementioned photopolymerization initiator from the adhesive layer 2 to the chip bonding layer 3 can be relatively suppressed. Moreover, in the pick-up process described later, where the chip bonding layer 3 is peeled off from the adhesive layer 2 and the semiconductor chip is removed in a state with the chip bonding layer 3 attached, the adhesive layer 2 can be peeled off from the chip bonding layer 3 more easily.

[0085] Furthermore, the aforementioned polydispersity Mw / Mn is preferably 10 or less, more preferably 5 or less, and even more preferably 3 or less.

[0086] It should be noted that, in this specification, the molecular weight distribution curve refers to the differential molecular weight distribution curve.

[0087] The GPC determination of the adhesive layer 2 before curing can be performed using the HLC-8220GPC manufactured by Tosoh Corporation as an analytical device, and the following test conditions can be applied to the test samples prepared in the following order.

[0088] [Preparation of the test sample]

[0089] (1) Take a sample of about 0.2g from the adhesive layer 2 before curing.

[0090] (2) After wrapping the aforementioned sample with a mesh sheet, it was immersed in about 30 mL of toluene at room temperature (23±2℃) for 1 week.

[0091] (3) Remove the mesh sheet from the toluene, remove the toluene-insoluble components contained in the mesh sheet, and obtain a toluene solution containing toluene-soluble components.

[0092] (4) The aforementioned toluene solution was treated under reduced pressure at a temperature below 45°C to remove toluene from the aforementioned toluene solution and obtain a solid substance containing the dissolved toluene components.

[0093] (5) Dissolve the aforementioned solid substance in tetrahydrofuran (THF) to a concentration of 0.2% by mass to prepare a THF solution, and then let it stand overnight.

[0094] (6) The THF solution that had been left overnight was filtered through a 0.45 μm membrane filter, and the resulting filtrate was used as the test sample.

[0095] [Measurement Conditions]

[0096] • Pillar: One TSKgel quaudcolumn SuperHZ-L (hereinafter referred to as Pillar 1) manufactured by Tosoh Corporation, and

[0097] Two TSKgel SuperHZM-M (hereinafter referred to as the second column) manufactured by Tosoh Corporation

[0098] The aforementioned columns are arranged in the aforementioned analytical apparatus such that two of the aforementioned second columns are connected in series on the downstream side of the aforementioned first column, and the eluent, described later, flows in from the side of the aforementioned first column.

[0099] Column temperature: 40℃

[0100] • Eluent: Tetrahydrofuran (THF)

[0101] • Flow rate: Sample pump flow rate 0.3 mL / min

[0102] Reference pump flow rate: 1.0 mL / min

[0103] Injection volume: 10μL

[0104] • Detector: Differential Refractive Index Detector (RI)

[0105] In addition, in order to obtain a molecular weight distribution curve (differential molecular weight distribution curve) based on the results obtained from the aforementioned test samples, each standard polystyrene manufactured by Tosoh Corporation was measured in a manner that resulted in the mixed mass shown in Table 1 below. Each measured standard polystyrene was dissolved in 100 mL of THF to obtain standard polystyrene solution STD1 and standard polystyrene solution STD2. These solutions were also subjected to GPC determination using the aforementioned measuring apparatus under the aforementioned measuring conditions.

[0106] [Table 1]

[0107]

[0108] The results obtained from GPC measurements of the aforementioned test samples, STD1, and STD2 were analyzed using GPC-8020 Model II (Data Management Version 5.10) software manufactured by Tosoh Corporation.

[0109] In the data analysis using the aforementioned analysis software, firstly, calibration curves for STD1 and STD2 are constructed (calibration curves with time (minutes) on the horizontal axis and the logarithm of weight-average molecular weight on the vertical axis). Data analysis of the molecular weight of the aforementioned test samples is then performed based on these calibration curves. The molecular weight analysis of the aforementioned test samples is conducted based on the molecular weight distribution curve of the earliest detected peak P1 (the peak on the highest molecular weight side) on the chromatogram. By analyzing the molecular weight distribution curve of peak P1, the number-average molecular weight Mn and weight-average molecular weight Mw of peak P1 can be obtained.

[0110] It should be noted that when the descending portion of the earliest detected peak P1 and the ascending portion of the peak P2 detected after peak P1 are observed to overlap, a baseline is drawn extending horizontally from the starting point of the ascending portion of peak P1. A vertical line is drawn from the aforementioned baseline to the valley portion (the most concave part) formed between the descending portion of peak P1 and the ascending portion of peak P2. The region separated by the aforementioned baseline from the starting point of the ascending portion of peak P1 to the aforementioned valley portion, and the line drawn vertically from the aforementioned baseline to the aforementioned valley portion is analyzed. Thus, the number-average molecular weight Mn and weight-average molecular weight Mw of peak P1 can be obtained.

[0111] In the molecular weight distribution curve obtained by GPC measurement of the adhesive layer 2 before curing, the peak molecular weight value of the peak appearing on the highest molecular weight side is preferably 33,000 or less, more preferably 25,000 or less. By keeping the peak molecular weight value of the peak appearing on the highest molecular weight side within the above-mentioned range, the space near the molecular chains of the polymer components contained in the adhesive layer 2 can be relatively reduced, thus further suppressing the transfer of the aforementioned photopolymerization initiator from the adhesive layer 2 to the chip bonding layer 3.

[0112] Furthermore, in the molecular weight distribution curve obtained by GPC measurement of the adhesive layer 2 before curing, the peak molecular weight value of the peak appearing on the highest molecular weight side is preferably 4000 or more, more preferably 8000 or more. By ensuring that the peak molecular weight value of the peak appearing on the highest molecular weight side is within the above-mentioned range, the space generated between the polymer components contained in the adhesive layer 2 can be relatively reduced. As a result, the transfer of the aforementioned photopolymerization initiator from the adhesive layer 2 to the chip bonding layer 3 can be further suppressed.

[0113] The adhesive layer 2 before curing preferably contains less than 32% by mass of sol component.

[0114] Although it is believed that the aforementioned photopolymerization initiator will transfer from the adhesive layer 2 to the chip bonding layer 3 with the help of the sol component, by making the sol component within the above-mentioned numerical range, the transfer of the aforementioned photopolymerization initiator from the adhesive layer 2 to the chip bonding layer 3 can be further suppressed.

[0115] Furthermore, the aforementioned adhesive layer 2 before curing preferably contains less than 23% by mass of sol component.

[0116] By setting the above-mentioned numerical range of the sol component, the transfer of the aforementioned photopolymerization initiator from the adhesive layer 2 to the chip bonding layer 3 can be further suppressed. Furthermore, in the pick-up process of peeling the chip bonding layer 3 from the adhesive layer 2 and removing the semiconductor chip with the chip bonding layer 3 attached, the chip bonding layer 3 can be more easily peeled off from the adhesive layer 2.

[0117] It should be noted that, in this specification, the sol component, as described in the determination of the mass ratio of the sol component below, refers to the component that dissolves in the aforementioned toluene after taking approximately 0.2 g of sample from the adhesive layer 2 before curing and immersing the sample in approximately 30 mL of toluene for one week.

[0118] The mass ratio of the sol component in the adhesive layer 2 before curing can be calculated as follows.

[0119] [Determination of the mass ratio of sol components]

[0120] (1) Take a sample of about 0.2g from the adhesive layer 2 before curing.

[0121] (2) After wrapping the aforementioned sample with a mesh sheet, it was immersed in about 30 mL of toluene for 1 week at room temperature.

[0122] (3) Remove the mesh sheet from the toluene and remove the toluene-insoluble components contained in the mesh sheet.

[0123] (4) After drying the aforementioned toluene-insoluble component at 130°C for about 2 hours under normal pressure, weigh the aforementioned toluene-insoluble component.

[0124] (5) Calculate the mass ratio of the gel component according to the following formula (1), and calculate the mass ratio of the sol component according to the following formula (2) based on the calculated value of the mass ratio of the gel rate.

[0125] The mass ratio of the gel component (mass%) = [(weighed value of the toluene-insoluble component) / mass of the sample taken] × 100···(1)

[0126] Mass ratio of sol component (mass%) = 100 - Mass ratio of gel component obtained from formula (1) above...(2)

[0127] The peel force of the chip bonding layer 3 relative to the adhesive layer 2 is preferably less than 0.18 N / 20 mm after the adhesive layer 2 has cured, more preferably less than 0.15 N / 20 mm, and even more preferably less than 0.07 N / 20 mm.

[0128] By ensuring that the peel force of the chip bonding layer 3 relative to the adhesive layer 2 after the adhesive layer 2 has cured is within the aforementioned numerical range, the chip bonding layer 3 can be more easily peeled from the adhesive layer 2 during the aforementioned pick-up process.

[0129] Furthermore, the peel force of the chip bonding layer 3 relative to the adhesive layer 2 is preferably 0.01 N / 20 mm or more after the adhesive layer 2 has cured.

[0130] Furthermore, by ensuring that the peel force of the chip bonding layer 3 relative to the adhesive layer 2 after the adhesive layer 2 has been cured is less than 0.07 N / 20 mm, the chip bonding layer 3 can be peeled off from the adhesive layer 2 particularly easily during the pick-up process described above.

[0131] The cured adhesive layer 2 can be irradiated with radiation of a specified intensity (e.g., 150 J / cm) by the self-adhesive diced chip bonding film 20 with a backing tape 10. 2 It is obtained from ultraviolet rays.

[0132] The peel force of the chip bonding layer 3 relative to the adhesive layer 2 after the adhesive layer 2 has cured can be determined by a T-peel test. The T-peel test can be performed as follows: After the adhesive layer 2 is cured by irradiating a cut chip bonding film 20 with a backing tape (e.g., "ELP BT315" manufactured by Nitto Denko Corporation) attached to the exposed surface of the chip bonding layer 3 with radiation of a specified intensity, a sample of the adhesive layer 2 with a width of 50 mm and a length of 120 mm is cut from the cured adhesive layer 2 as a test sample. The test is performed using a tensile tester (e.g., "TG-1kN" manufactured by Minebea Mitsumi Inc.) at a temperature of 25°C and a tensile speed of 300 mm / min.

[0133] The peel force of the chip bonding layer 3 relative to the adhesive layer 2 is preferably 0.3 N / 20 mm or more before the adhesive layer 2 is cured.

[0134] In the adhesive layer 2 before curing, by making the peel force of the chip bonding layer 3 relative to the adhesive layer 2 within the aforementioned numerical range, the adhesive layer 2 can adequately hold the chip bonding layer 3. This further suppresses chip lifting that occurs after the chip bonding layer 3 is monolithized.

[0135] Furthermore, the peel force of the chip bonding layer 3 relative to the adhesive layer 2 is preferably less than 5.0 N / 20 mm before the adhesive layer 2 is cured.

[0136] Before the adhesive layer 2 is cured, the peel force of the chip bonding layer 3 relative to the adhesive layer 2 can be determined by a T-peel test. The T-peel test can be performed as follows: a film with a width of 20 mm and a length of 120 mm is cut from the chip bonding film 20 with a backing tape (e.g., "ELP BT315" manufactured by Nitto Denko Corporation) attached to the exposed surface of the chip bonding layer 3. This film is used as a test sample and is tested using a tensile tester (e.g., "TG-1kN" manufactured by Minebea Mitsumi Inc.) at a temperature of 25°C and a tensile speed of 300 mm / min.

[0137] The adhesive layer 2 may also include an external crosslinking agent. Any substance can be used as the external crosslinking agent, as long as it can react with the base polymer (e.g., an acrylic polymer) to form a crosslinked structure. Examples of such external crosslinking agents include polyisocyanate compounds, epoxy compounds, polyol compounds, aziridine compounds, and melamine-based crosslinking agents.

[0138] When the adhesive layer 2 contains an external crosslinking agent, the adhesive layer 2 preferably contains 0.1 parts by weight or more and 3 parts by weight of the aforementioned external crosslinking agent.

[0139] In addition to the above-mentioned components, the adhesive layer 2 may also contain tackifiers, antioxidants, crosslinking accelerators, anti-aging agents, pigments, or colorants such as dyes.

[0140] The thickness of the adhesive layer 2 is preferably 1 μm or more and 50 μm or less, more preferably 2 μm or more and 30 μm or less, and even more preferably 5 μm or more and 25 μm or less.

[0141] The thickness of adhesive layer 2 can be determined, for example, by measuring the thickness at any five randomly selected points using a digital micrometer (manufactured by PEACOCK, model R-205) and then averaging these thicknesses.

[0142] Substrate layer 1 supports adhesive layer 2. Substrate layer 1 is made using a resin film. Examples of resins included in the resin film include polyolefins, polyesters, polyurethanes, polycarbonates, polyetheretherketones, polyimides, polyetherimides, polyamides, fully aromatic polyamides, polyvinyl chloride, polyvinylidene chloride, polyphenylene sulfide, fluoropolymers, cellulose resins, and silicone resins.

[0143] Examples of polyolefins include homopolymers of α-olefins, copolymers of two or more α-olefins, block polypropylene, random polypropylene, and copolymers of one or more α-olefins with other vinyl monomers.

[0144] As a homopolymer of α-olefin, a homopolymer of α-olefin with 2 or more and 12 or fewer carbon atoms is preferred. Examples of such homopolymers include ethylene, propylene, 1-butene, and 4-methyl-1-pentene.

[0145] Examples of copolymers containing two or more α-olefins include ethylene-propylene copolymers, ethylene-1-butene copolymers, ethylene-propylene-1-butene copolymers, copolymers of ethylene with α-olefins having 5 or more but less than 12 carbon atoms, propylene-ethylene copolymers, propylene-1-butene copolymers, and copolymers of propylene with α-olefins having 5 or more but less than 12 carbon atoms.

[0146] Examples of copolymers of one or more α-olefins with other vinyl monomers include ethylene-vinyl acetate copolymer (EVA).

[0147] Polyolefins can be substances referred to as α-olefin-based thermoplastic elastomers. Examples of α-olefin-based thermoplastic elastomers include substances obtained by combining propylene-ethylene copolymers with propylene homopolymers, or propylene-ethylene-α-olefin terpolymers with 4 or more carbon atoms.

[0148] Commercially available α-olefin-based thermoplastic elastomers include, for example, Vistamaxx 3980 (manufactured by ExxonMobil Chemical Company), a propylene-based elastomer resin.

[0149] The resin film may contain one of the aforementioned resins, or it may contain two or more of the aforementioned resins.

[0150] It should be noted that when the adhesive layer 2 contains the UV-curable adhesive described later, the resin film used to make the substrate layer 1 is preferably constructed in a manner that is UV-transmittable.

[0151] The substrate layer 1 can be a single-layer structure or a multilayer structure. The substrate layer 1 can be obtained by non-stretch forming or by stretch forming, preferably by stretch forming. When the substrate layer 1 is a multilayer structure, the substrate layer 1 preferably has a layer containing an elastomer (hereinafter referred to as the elastomer layer) and a layer containing a non-elastomer (hereinafter referred to as the non-elastomer layer).

[0152] By incorporating both an elastomer layer and a non-elastomer layer into the substrate layer 1, the elastomer layer can function as a stress relaxation layer to relieve tensile stress. That is, because the tensile stress generated in the substrate layer 1 is relatively small, the substrate layer 1 can possess moderate hardness and be relatively easy to stretch.

[0153] This improves the cutting performance of semiconductor wafers into multiple semiconductor chips.

[0154] Furthermore, during the cutting process in the expansion step, it is possible to prevent the substrate layer 1 from cracking and being damaged.

[0155] It should be noted that, in this specification, the term "elastomeric layer" refers to a low elastic modulus layer whose tensile storage modulus at room temperature is lower than that of a non-elastomeric layer. Examples of elastomeric layers include those with a tensile storage modulus of 10 MPa or more and 200 MPa or less at room temperature; examples of non-elastomeric layers include those with a tensile storage modulus of 200 MPa or more and 500 MPa or less at room temperature.

[0156] The elastomer layer may contain one type of elastomer or two or more types of elastomers, preferably α-olefin thermoplastic elastomers and EVA (ethylene-vinyl acetate copolymer).

[0157] The non-elastic layer may contain one type of non-elastic material or two or more types of non-elastic materials, preferably metallocene PP as described later.

[0158] When the substrate layer 1 has an elastomer layer and a non-elastomer layer, the substrate layer 1 is preferably formed as a three-layer structure (non-elastomer layer / elastomer layer / non-elastomer layer) with an elastomer layer as the central layer and non-elastomer layers on two opposite sides of the central layer.

[0159] Furthermore, as described above, in the cut-holding process, since the cut-chip bonding film, which is maintained in an extended state, is thermally contracted by blowing hot air (e.g., 100–130°C) at room temperature (e.g., 23°C), and then cooled and cured, the outermost layer of the substrate layer 1 preferably contains a resin having a melting point similar to that of the hot air blown onto the cutting strip. This allows the outermost layer, which is melted by the blowing hot air, to cure more rapidly.

[0160] As a result, the incision can be maintained more effectively during the incision maintenance process.

[0161] The substrate layer 1 is a laminated structure of an elastomer layer and a non-elastomer layer. When the elastomer layer comprises an α-olefin-based thermoplastic elastomer and the non-elastomer layer comprises a metallocene PP or other polyolefin (described later), the elastomer layer preferably comprises an α-olefin-based thermoplastic elastomer in an amount of 50% to 100% by mass relative to the total mass of the elastomer forming the elastomer layer. More preferably, it comprises 70% to 100% by mass, even more preferably, it comprises 80% to 100% by mass, particularly preferably, it comprises 90% to 100% by mass, and most preferably, it comprises 95% to 100% by mass. By including an α-olefin-based thermoplastic elastomer within the aforementioned range, the affinity between the elastomer layer and the non-elastomer layer increases, thus making it easier to extrude the substrate layer 1. Furthermore, the elastomer layer can function as a stress relaxation layer, thereby enabling efficient cutting of semiconductor wafers adhered to dicing tapes.

[0162] When the substrate layer 1 is a laminated structure of an elastomer layer and a non-elastomer layer, the substrate layer 1 is preferably obtained by co-extrusion molding to form a laminated structure of elastomer and non-elastomer layers through co-extrusion of the elastomer and the non-elastomer. As a co-extrusion molding process, any suitable co-extrusion molding process commonly used in the manufacture of films, sheets, etc. can be used. From the viewpoint of obtaining the substrate layer 1 efficiently and inexpensively, blow molding and co-extrusion T-die molding are preferred in co-extrusion molding.

[0163] When the substrate layer 1 forming the laminated structure is obtained by co-extrusion molding, the aforementioned elastomer layer and the aforementioned non-elastic layer are heated and brought into contact in a molten state. Therefore, it is preferable that the melting point difference between the aforementioned elastomer and the aforementioned non-elastic material is small. By making the melting point difference small, overheating of either the aforementioned elastomer or the aforementioned non-elastic material, which has a low melting point, is suppressed. Therefore, it is possible to suppress the generation of byproducts due to thermal degradation of either the aforementioned elastomer or the aforementioned non-elastic material, which has a low melting point. In addition, it is also possible to suppress poor lamination between the aforementioned elastomer layer and the aforementioned non-elastic material due to excessive reduction in viscosity of either the aforementioned elastomer or the aforementioned non-elastic material, which has a low melting point. The melting point difference between the aforementioned elastomer and the aforementioned non-elastic material is preferably 0°C or higher and 70°C or lower, more preferably 0°C or higher and 55°C or lower.

[0164] The melting points of the aforementioned elastomers and non-elastic materials can be determined using differential scanning calorimetry (DSC). For example, they can be determined by using a differential scanning calorimeter (TA INSTRUMENTS, model: DSC Q2000) to heat the material to 200°C at a rate of 5°C / min under a nitrogen flow and then determining the peak temperature of the endothermic peak.

[0165] The thickness of the substrate layer 1 is preferably 55 μm or more and 195 μm or less, more preferably 55 μm or more and 190 μm or less, even more preferably 55 μm or more and 170 μm or less, and most preferably 60 μm or more and 160 μm or less. By making the thickness of the substrate layer 1 within the aforementioned range, the dicing tape can be manufactured efficiently, and the semiconductor wafers attached to the dicing tape can be cut efficiently.

[0166] The thickness of substrate layer 1 can be determined, for example, by using a direct-reading thickness gauge (PEACOCK, model: R-205) to measure the thickness at any five randomly selected points and then taking the arithmetic mean of these thicknesses.

[0167] In the substrate layer 1 formed by stacking an elastomer layer and a non-elastomer layer, the ratio of the thickness of the non-elastomer layer to the thickness of the elastomer layer is preferably 1 / 25 or more and 1 / 3 or less, more preferably 1 / 25 or more and 1 / 3.5 or less, even more preferably 1 / 25 or more and 1 / 4 or less, particularly preferably 1 / 22 or more and 1 / 4 or less, and most preferably 1 / 20 or more and 1 / 4 or less. By setting the ratio of the thickness of the non-elastomer layer to the thickness of the elastomer layer to the above range, the semiconductor wafer attached to the dicing tape can be cut more efficiently.

[0168] The elastomer layer can be a single-layer (1-layer) structure or a multilayer structure. The elastomer layer is preferably a structure of 1 to 5 layers, more preferably a structure of 1 to 3 layers, even more preferably a structure of 1 to 2 layers, and a single-layer structure is most preferred. When the elastomer layer is a multilayer structure, all layers may contain the same elastomer, or at least two layers may contain different elastomers.

[0169] The non-elastic layer can be a single-layer (1-layer) structure or a multilayer structure. The non-elastic layer is preferably a structure of 1 to 5 layers, more preferably a structure of 1 to 3 layers, even more preferably a structure of 1 to 2 layers, and most preferably a single-layer structure. When the non-elastic layer is a multilayer structure, all layers may contain the same non-elastic material, or at least 2 layers may contain different non-elastic materials.

[0170] The non-elastic layer preferably comprises polypropylene resin (hereinafter referred to as metallocene PP), which is a polymerization product obtained using a metallocene catalyst, as the non-elastic layer. Examples of metallocene PP include propylene-α-olefin copolymers, which are polymerization products obtained using a metallocene catalyst. By including metallocene PP in the non-elastic layer, it is possible to efficiently manufacture dicing tapes and efficiently cut semiconductor wafers attached to the dicing tapes.

[0171] It should be noted that, as a commercially available metallocene PP, WINTEC WFX4M (manufactured by Japan Polypropylene Co., Ltd.) is an example.

[0172] Here, the metallocene catalyst is a catalyst comprising a transition metal compound of Group 4 of the periodic table (so-called metallocene compound), and a co-catalyst capable of reacting with the metallocene compound to activate it into a stable ionic state. The Group 4 transition metal compound comprises a ligand having a cyclopentadienyl skeleton, and the metallocene catalyst may, as needed, contain an organoaluminum compound. The metallocene compound is a cross-linked metallocene compound capable of stereoregular polymerization of propylene.

[0173] Among the aforementioned propylene-α-olefin copolymers that are polymerization products of metallocene catalysts, propylene-α-olefin random copolymers that are polymerization products of metallocene catalysts are preferred. Among the aforementioned propylene-α-olefin random copolymers that are polymerization products of metallocene catalysts, copolymers selected from propylene-2-carbon α-olefin random copolymers, propylene-4-carbon α-olefin random copolymers, and propylene-5-carbon α-olefin random copolymers that are polymerization products of metallocene catalysts are preferred. Among these, propylene-ethylene random copolymers that are polymerization products of metallocene catalysts are most suitable.

[0174] For the aforementioned propylene-α-olefin random copolymers that are polymer products of metallocene catalysts, from the viewpoint of co-extrusion film formation with the aforementioned elastomer layer and cuttable properties when attached to a semiconductor wafer with a dicing tape, a melting point of 80°C or higher and 140°C or lower, particularly 100°C or higher and 130°C or lower, is preferred.

[0175] The melting point of the propylene-α-olefin random copolymer, which is the polymerization product of the aforementioned metallocene catalyst, can be determined using the aforementioned method.

[0176] Here, if the aforementioned elastomer layer is disposed on the outermost layer of the substrate layer 1, the aforementioned elastomer layers disposed on the outermost layer tend to stick together when the substrate layer 1 is rolled into a roll. Therefore, it becomes difficult to unwind the substrate layer 1 from the roll. In contrast, the preferred configuration of the aforementioned laminated substrate layer 1 is a non-elastic layer / elastic layer / non-elastic layer, that is, the non-elastic layer is disposed on the outermost layer, and therefore the substrate layer 1 in this configuration has excellent resistance to adhesion. As a result, it is possible to suppress the manufacturing delay of the semiconductor device using the dicing tape 10 caused by adhesion.

[0177] The aforementioned non-elastic layer preferably comprises a resin having a melting point of 100°C or higher and 130°C or lower, and a molecular weight dispersion (weight-average molecular weight / number-average molecular weight) of 5 or lower. Metallocene PP is an example of such a resin.

[0178] By including the aforementioned non-elastomeric layer in the resin as described above, the non-elastomeric layer can be cooled and cured more rapidly during the cut-holding process. Therefore, shrinkage of the substrate layer 1 after the cutting strip has been thermally shrunk can be more effectively suppressed.

[0179] Therefore, the incision can be maintained more effectively during the incision maintenance process.

[0180] The chip bonding layer 3 preferably has thermosetting properties. The chip bonding layer 3 can be given thermosetting properties by including at least one of a thermosetting resin and a thermoplastic resin having thermosetting functional groups.

[0181] When the chip bonding layer 3 comprises a thermosetting resin, examples of such thermosetting resins include epoxy resin, phenolic resin, amino resin, unsaturated polyester resin, polyurethane resin, silicone resin, and thermosetting polyimide resin. Among these, epoxy resin is preferred.

[0182] Examples of epoxy resins include bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenolic varnish type, o-cresol phenolic varnish type, trihydroxyphenylmethane type, tetraphenol ethane type, hydantoin type, triglycidyl isocyanurate type, and glycidylamine type epoxy resins.

[0183] Phenolic resins used as curing agents for epoxy resins include, for example, phenolic varnish-type phenolic resins, methyl phenolic resins, and polyoxystyrene such as polyoxystyrene.

[0184] When the chip bonding layer 3 comprises a thermoplastic resin having thermosetting functional groups, examples of such thermoplastic resins include, for example, acrylic resins containing thermosetting functional groups. Examples of acrylic resins containing thermosetting functional groups include acrylic resins comprising monomer units derived from (meth)acrylates.

[0185] For thermosetting resins with thermosetting functional groups, the curing agent can be selected according to the type of thermosetting functional group.

[0186] From the viewpoint of ensuring the full progress of the curing reaction of the resin components or increasing the curing reaction rate, the chip bonding layer 3 may also contain a thermosetting catalyst (curing accelerator). Examples of thermosetting catalysts include imidazole compounds, triphenylphosphine compounds, amine compounds, and trihaloborane compounds.

[0187] The chip bonding layer 3 may contain a thermoplastic resin. The thermoplastic resin acts as an adhesive. Examples of thermoplastic resins include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylate copolymer, polybutadiene resin, polycarbonate resin, thermoplastic polyimide resin, polyamide 6, polyamide 6,6 and other polyamide resins, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamide-imide resins, and fluoropolymers. Only one of the above-mentioned thermoplastic resins may be used, or two or more may be used in combination. From the viewpoint of having fewer ionic impurities and higher heat resistance, thus easily ensuring the reliability of the connection based on the chip bonding layer, acrylic resins are preferred as the above-mentioned thermoplastic resins.

[0188] The aforementioned acrylic resin is preferably a polymer in which monomer units derived from (meth)acrylates are the most abundant monomer units by mass proportion. Examples of (meth)acrylates include, for example, alkyl (meth)acrylates, cycloalkyl (meth)acrylates, and aryl (meth)acrylates. The aforementioned acrylic resin may contain monomer units derived from other components capable of copolymerizing with (meth)acrylates. Examples of such other components include, for example, carboxyl-containing monomers, anhydride monomers, hydroxyl-containing monomers, glycidyl-containing monomers, sulfonic acid-containing monomers, phosphate-containing monomers, acrylamide, acrylonitrile, and other functionalized monomers, as well as various multifunctional monomers. From the viewpoint of achieving high cohesion in the chip bonding layer, the aforementioned acrylic resin is preferably a copolymer of (meth)acrylate (especially alkyl (meth)acrylate with alkyl groups having 4 or fewer carbon atoms) and carboxyl-containing monomers, nitrogen-containing monomers, and polyfunctional monomers (especially polyglycidyl polyfunctional monomers), and more preferably a copolymer of ethyl acrylate and butyl acrylate, acrylic acid, acrylonitrile, and polyglycidyl (meth)acrylate.

[0189] Depending on the requirements, the chip bonding layer 3 may contain one or more other components. Examples of other components include flame retardants, silane coupling agents, and ion trapping agents.

[0190] The thickness of the chip bonding layer 3 is not particularly limited, for example, it can be 1 μm or more and 200 μm or less. The thickness can be 3 μm or more and 150 μm or less, or 5 μm or more and 100 μm or less.

[0191] The die-cutting bonding film 20 of this embodiment can be used, for example, as an auxiliary tool for manufacturing semiconductor integrated circuits. Specific examples of using the die-cutting bonding film 20 will be described below.

[0192] The following describes an example of a die bonding film 20 using a substrate layer 1 as a single layer.

[0193] A method for manufacturing semiconductor integrated circuits includes the following steps: a half-dicing step, which forms grooves on a semiconductor wafer to be processed into a chip (die) by dicing; a back-side grinding step, which reduces the thickness of the semiconductor wafer after the half-dicing step by grinding; a mounting step, which attaches one side of the semiconductor wafer after the back-side grinding step (e.g., the side opposite to the circuit surface) to a chip bonding layer 3 and fixes the semiconductor wafer to a dicing tape 10; an expansion step, which increases the spacing between the half-diced semiconductor chips; a cut-holding step, which maintains the spacing between the semiconductor chips; a pick-up step, which peels the chip bonding layer 3 from the adhesive layer 2 and removes the semiconductor chip (die) with the chip bonding layer 3 attached; and a chip bonding step, which attaches the semiconductor chip (die) with the chip bonding layer 3 attached to a substrate. When performing these steps, the dicing tape (dicing chip bonding film) of this embodiment is used as a manufacturing aid.

[0194] In the semi-cutting process, such as Figure 2A and Figure 2B As shown, a half-dicing process is implemented to cut a semiconductor integrated circuit into dies. Specifically, a wafer processing tape T (see reference) is attached to the side of the semiconductor wafer W opposite to the circuit surface. Figure 2A Additionally, the dicing ring R is mounted on the wafer processing belt T (see reference). Figure 2A (Refer to) forming cleaving grooves while wafer processing tape with a T-shaped marking is attached (see...) Figure 2B In the back-side grinding process, such as Figure 2C and Figure 2D As shown, the semiconductor wafer is thinned by grinding. Specifically, a back-side grinding tape G is attached to the grooved surface, while the initially attached wafer processing tape T is peeled off (see reference). Figure 2C Grinding is performed with the back-side grinding tape G attached until the semiconductor wafer W reaches the specified thickness (see reference). Figure 2D ).

[0195] It should be noted that in the back-side grinding process, when the semiconductor wafer is particularly thin with a thickness of 20 μm or more and less than 30 μm, the semiconductor chip is prone to deformation and breakage when the pin member P is used to lift the semiconductor chip in the pick-up process described later. However, since the chip bonding film 20 of this embodiment is constructed as described above, it is possible to relatively suppress the deformation and breakage of the semiconductor chip in the pick-up process.

[0196] During the installation process, such as Figures 3A-3B As shown, after the dicing ring R is mounted on the adhesive layer 2 of the dicing tape 10, the semi-diced semiconductor wafer W is pasted onto the exposed chip bonding layer 3 (see reference). Figure 3A Then, the back-side polishing tape G is peeled off from the semiconductor wafer W (refer to...). Figure 3B ).

[0197] In extended processes, such as Figures 4A to 4C As shown, the cutting ring R is fixed to the retaining member H of the expansion device. The chip bonding film 20 is lifted from below using the lifting member U of the expansion device, thereby stretching the chip bonding film 20 and expanding it along the surface direction (see reference). Figure 4B Therefore, the semi-cut semiconductor wafer W is cut under specific temperature conditions. These temperature conditions are, for example, -20 to 5°C, preferably -15 to 0°C, and more preferably -10 to -5°C. The extended state is released by lowering the lifting member U (see reference). Figure 4C ).

[0198] Furthermore, in the extended process, such as Figures 5A-5B As shown, the dicing strip 10 is stretched under higher temperature conditions (e.g., room temperature (23±2℃)) to increase its area. This causes the adjacent, cut semiconductor chips to separate in the planar direction of the thin film surface, further increasing the spacing.

[0199] In the incision maintenance process, such as Figure 6 As shown, hot air (e.g., 100-130°C) is blown onto the cutting strip 10 to cause it to shrink thermally, and then it is cooled and solidified to maintain the distance (cut) between adjacent semiconductor chips.

[0200] In the picking process, such as Figure 7 As shown, the semiconductor chip with the chip bonding layer 3 attached is peeled off from the adhesive layer 2 of the dicing tape 10. Specifically, the pin member P is raised, thereby lifting the semiconductor chip being picked up across the dicing tape 10. The lifted semiconductor chip is held in place by an adsorption clamp J.

[0201] In the chip bonding process, a semiconductor chip with chip bonding layer 3 attached is bonded to a substrate.

[0202] The matters disclosed in this specification include the following. (1)

[0204] A chip bonding film for cutting chips, comprising:

[0205] A cut strip with an adhesive layer laminated on top of the substrate layer, and

[0206] A chip bonding layer is stacked on the adhesive layer of the aforementioned dicing tape;

[0207] The aforementioned adhesive layer comprises an adhesive and a photopolymerization initiator.

[0208] In the molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the ratio of the weight average molecular weight Mw of the peak appearing on the highest molecular weight side to the number average molecular weight Mn of the peak appearing on the highest molecular weight side, i.e., the polydispersity Mw / Mn, is 1.3 or higher.

[0209] According to this configuration, the transfer of the aforementioned photopolymerization initiator from the aforementioned adhesive layer to the aforementioned chip bonding layer can be relatively suppressed. (2)

[0211] According to the chip bonding film described in (1) above, the aforementioned polydispersity Mw / Mn is 2.0 or higher.

[0212] According to this configuration, the transfer of the aforementioned photopolymerization initiator from the aforementioned adhesive layer to the aforementioned chip bonding layer can be relatively suppressed, and in the pick-up process of peeling the aforementioned chip bonding layer and the aforementioned adhesive layer apart and taking out the semiconductor chip in a state with the aforementioned chip bonding layer attached, the aforementioned chip bonding layer can be peeled off from the aforementioned adhesive layer more easily. (3)

[0214] According to the chip bonding film cut as described in (1) or (2) above, wherein,

[0215] The aforementioned polydispersity Mw / Mn is below 10. (4)

[0217] According to the chip bonding film cut as described in (1) or (2) above, wherein,

[0218] The aforementioned polydispersity Mw / Mn is below 5. (5)

[0220] According to the chip bonding film cut as described in (1) or (2) above, wherein,

[0221] The aforementioned polydispersity Mw / Mn is below 3. (6)

[0223] The chip bonding film according to any one of (1) to (5) above, wherein,

[0224] In the molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the peak molecular weight of the peak appearing on the highest molecular weight side is below 33,000. (7)

[0226] The chip bonding film according to any one of (1) to (6) above, wherein,

[0227] In the molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the peak molecular weight of the peak appearing on the highest molecular weight side is below 25,000.

[0228] According to this configuration, the transfer of the aforementioned photopolymerization initiator from the aforementioned adhesive layer to the aforementioned chip bonding layer can be further suppressed. (8)

[0230] According to the chip bonding film cut according to (6) or (7) above, wherein,

[0231] In the molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the peak molecular weight of the peak appearing on the highest molecular weight side is above 4000. (9)

[0233] According to the chip bonding film cut according to (6) or (7) above, wherein,

[0234] In the molecular weight distribution curve obtained by GPC measurement of the aforementioned adhesive layer before curing, the peak molecular weight of the peak appearing on the highest molecular weight side is above 8000. (10)

[0236] The chip bonding film according to any one of (1) to (9) above, wherein,

[0237] The aforementioned adhesive layer before curing contains less than 32% by mass of sol component.

[0238] According to this configuration, the transfer of the aforementioned photopolymerization initiator from the aforementioned adhesive layer to the aforementioned chip bonding layer can be further suppressed. (11)

[0240] The chip bonding film according to any one of (1) to (10) above, wherein,

[0241] The aforementioned adhesive layer before curing contains less than 23% by mass of sol components.

[0242] According to this configuration, the transfer of the aforementioned photopolymerization initiator from the aforementioned adhesive layer to the aforementioned chip bonding layer can be further suppressed, and in the pick-up process of peeling the aforementioned chip bonding layer and the aforementioned adhesive layer apart and taking out the semiconductor chip in a state with the aforementioned chip bonding layer attached, the aforementioned chip bonding layer can be peeled off from the aforementioned adhesive layer more easily. (12)

[0244] The chip bonding film according to any one of (1) to (11) above, wherein,

[0245] The peel force of the aforementioned chip bonding layer relative to the aforementioned adhesive layer is less than 0.18 N / 20 mm after the aforementioned adhesive layer has cured. (13)

[0247] According to any one of (1) to (12) above, the chip bonding film is cut, wherein,

[0248] The peel force of the aforementioned chip bonding layer relative to the aforementioned adhesive layer is less than 0.15 N / 20 mm after the aforementioned adhesive layer has cured. (14)

[0250] The chip bonding film according to any one of (1) to (13) above, wherein,

[0251] The peel force of the aforementioned chip bonding layer relative to the aforementioned adhesive layer is less than 0.07 N / 20 mm after the aforementioned adhesive layer has cured.

[0252] According to this configuration, in the pick-up process of removing a semiconductor chip in a state where the chip bonding layer is attached by peeling it off from the aforementioned chip bonding layer and the aforementioned adhesive layer, the aforementioned chip bonding layer can be peeled off from the aforementioned adhesive layer more easily. (15)

[0254] The chip bonding film according to any one of (12) to (14) above, wherein the peel force of the chip bonding layer relative to the adhesive layer is 0.01 N / 20 mm or more after the adhesive layer is cured. (16)

[0256] The chip bonding film according to any one of (1) to (15) above, wherein the peel force of the chip bonding layer relative to the adhesive layer is 0.3 N / 20 mm or more before the adhesive layer is cured.

[0257] According to this configuration, the aforementioned chip bonding layer can be adequately held in place by the adhesive layer. This further suppresses chip floating that occurs after the aforementioned chip bonding layer is monolithized. (17)

[0259] According to the chip bonding film cutter described in (16) above, wherein,

[0260] The peel force of the aforementioned chip bonding layer relative to the aforementioned adhesive layer is less than 5.0 N / 20 mm before the aforementioned adhesive layer is cured.

[0261] It should be noted that the chip-dicing bonding film of the present invention is not limited to the foregoing embodiments. Furthermore, the chip-dicing bonding film of the present invention is not limited by the aforementioned effects. Various modifications can be made to the chip-dicing bonding film of the present invention without departing from the spirit of the invention.

[0262] Example

[0263] The present invention will now be further described in detail with reference to specific embodiments. These embodiments are merely examples used to further illustrate the invention and are not intended to limit the scope of the invention.

[0264] [Example 1]

[0265] <Making of Cutting Strips>

[0266] 11 parts by mass of 2-hydroxyethyl acrylate (hereinafter referred to as HEA), 89 parts by mass of isononyl acrylate (hereinafter referred to as INA), and 0.2 parts by mass of azobisisobutyronitrile (hereinafter referred to as AIBN) as a thermal polymerization initiator were added to a reaction vessel equipped with a condenser, a nitrogen inlet pipe, a thermometer, and a stirring device. Then, butyl acetate as a reaction solvent was added in such a way that the concentration of the aforementioned monomers reached 38%. The polymerization was carried out at 62°C for 4 hours under a nitrogen gas flow and then at 75°C for 2 hours to obtain acrylic polymer A.

[0267] 12 parts by mass of 2-methacryloyloxyethyl isocyanate (hereinafter referred to as MOI) and 0.06 parts by mass of dibutyltin dilaurate were added to the acrylic polymer A, and the addition reaction was carried out at 50°C for 12 hours under an air flow to obtain acrylic polymer A'.

[0268] Next, relative to 100 parts by weight of acrylic polymer A, 0.8 parts by weight of a polyisocyanate compound (trade name "CORONATE L", manufactured by Nippon Polyurethane Co., Ltd.) as an external crosslinking agent, 2 parts by weight of a photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.), and 0.01 parts by weight of an antioxidant (trade name "Irganox 1010", manufactured by BASF JAPAN) were added to prepare an adhesive solution (hereinafter sometimes referred to as adhesive solution A).

[0269] Next, adhesive solution A was applied using an applicator to the silicone-treated surface of the PET release liner (50 μm thick), which had undergone silicone release treatment. The surface was dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Subsequently, a polyolefin film (trade name "FUNCRARENED#125", 125 μm thick) manufactured by Gunze was adhered to this adhesive layer as a substrate layer and stored at 50°C for 24 hours to obtain cutting tape A.

[0270] <Fabrication of Chip Bonding Layer>

[0271] To prepare an adhesive composition A with a solid content of 30% by weight, 200 parts by weight of epoxy resin (trade name "KI-3000-4", manufactured by Toto Chemical Industries, Ltd.), 200 parts by weight of phenolic resin (trade name "MEHC-7851SS", manufactured by Meiwa Chemical Industries, Ltd.), 350 parts by weight of silica filler (trade name "SE2050-MCV", manufactured by ADMATECHS, Ltd., average particle size of 500 nm) and 2 parts by weight of curing accelerator (trade name "CUREZOL 2PHZ-PW", manufactured by Shikoku Chemical Industries, Ltd.) were added to methyl ethyl ketone, relative to 100 parts by weight of acrylic resin (trade name "TEISANRESIN SG-70L", manufactured by NAGASE CHEMTEX, weight average molecular weight of 900,000).

[0272] Next, adhesive composition A is applied to the silicone-treated surface of the PET separator (50 μm thick) with a smearer to form a coating film. This coating film is then subjected to a solvent removal treatment at 120°C for 2 minutes. This results in the fabrication of a chip bonding layer with an average thickness of 10 μm on the PET separator.

[0273] <Fabrication of chip bonding films>

[0274] A 330mmφ PET isolator with chip bonding layer is obtained by punching a PET isolator with chip bonding layer (hereinafter referred to as PET isolator with chip bonding layer) into a 330mmφ circle.

[0275] Next, after removing the PET separator from the cutting tape A to expose one side of the adhesive layer, a laminator is used to bond the PET separator with the chip bonding layer to the cutting tape A at room temperature (23±2℃) with the exposed side of the chip bonding layer against the exposed side of the adhesive layer, thereby obtaining the chip bonding film A.

[0276] That is, the cutting tape A in Example 1 is composed of a polyolefin film, an adhesive layer, a chip bonding layer and a PET separator stacked in sequence.

[0277] [Example 2]

[0278] <Making of Cutting Strips>

[0279] 16 parts by mass of HEA as a monomer, 84 parts by mass of butyl acrylate (hereinafter referred to as BA), and 0.2 parts by mass of AIBN as a thermal polymerization initiator were added to the same reaction vessel as described in Example 1. Then, butyl acetate as a reaction solvent was added at a concentration of 32% of the aforementioned monomers. The polymerization was carried out at 62°C for 4 hours under a nitrogen gas flow and then at 75°C for 2 hours to obtain acrylic polymer B.

[0280] Add 17 parts by mass of MOI and 0.09 parts by mass of dibutyltin dilaurate to the acrylic polymer B, and carry out an addition reaction at 50°C for 12 hours under an air flow to obtain acrylic polymer B'.

[0281] Next, relative to 100 parts by weight of acrylic polymer B, 0.8 parts by weight of a polyisocyanate compound (trade name "CORONATE L", manufactured by Nippon Polyurethane Co., Ltd.) as an external crosslinking agent, 2 parts by weight of a photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.), and 0.01 parts by weight of an antioxidant (trade name "Irganox 1010", manufactured by BASF JAPAN) were added to prepare an adhesive solution (hereinafter sometimes referred to as adhesive solution B).

[0282] Next, adhesive solution B was applied using an applicator to the silicone-treated surface of the PET release liner (50 μm thick), which had undergone silicone release treatment. The surface was dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Subsequently, a polyolefin film (trade name "FUNCRARENED#125", 125 μm thick) manufactured by Gunze was adhered to this adhesive layer as a substrate layer and stored at 50°C for 24 hours to obtain cutting tape B.

[0283] <Fabrication of Chip Bonding Layer>

[0284] Prepared in the same manner as in Example 1.

[0285] <Fabrication of chip bonding films>

[0286] After obtaining a 330mmφ PET separator with a chip bonding layer in the same manner as in Example 1, the PET separator is removed from the cutting tape B to expose one side of the adhesive layer. Using a laminator, the PET separator with the chip bonding layer is bonded to the cutting tape B at room temperature with the exposed side of the chip bonding layer abutting against the exposed side of the adhesive layer, thereby obtaining the chip bonding film B.

[0287] [Example 3]

[0288] <Making of Cutting Strips>

[0289] 11 parts by mass of HEA as a monomer, 89 parts by mass of 2-ethylhexyl acrylate (hereinafter referred to as 2EHA), and 0.2 parts by mass of AIBN as a thermal polymerization initiator were added to the same reaction vessel as described in Example 1. Then, butyl acetate as a reaction solvent was added at a concentration of 36% of the aforementioned monomers. The polymerization was carried out at 62°C for 4 hours under a nitrogen gas flow and then at 75°C for 2 hours to obtain acrylic polymer C.

[0290] Add 13 parts by mass of MOI and 0.07 parts by mass of dibutyltin dilaurate to the acrylic polymer C, and carry out an addition reaction at 50°C for 12 hours under an air flow to obtain acrylic polymer C'.

[0291] Next, relative to 100 parts by weight of the acrylic polymer C, 0.8 parts by weight of a polyisocyanate compound (trade name "CORONATE L", manufactured by Nippon Polyurethane Co., Ltd.) as an external crosslinking agent, 2 parts by weight of a photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.), and 0.01 parts by weight of an antioxidant (trade name "Irganox 1010", manufactured by BASF JAPAN) were added to prepare an adhesive solution (hereinafter sometimes referred to as adhesive solution C).

[0292] Next, adhesive solution C was applied using an applicator to the silicone-treated surface of the PET release liner (50 μm thick), which had undergone silicone release treatment. The surface was dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Subsequently, a polyolefin film (trade name "FUNCRARENED#125", 125 μm thick) manufactured by Gunze was adhered to this adhesive layer as a substrate layer and stored at 50°C for 24 hours to obtain the cutting tape C.

[0293] <Fabrication of Chip Bonding Layer>

[0294] Prepared in the same manner as in Example 1.

[0295] <Fabrication of chip bonding films>

[0296] After obtaining a 330mmφ PET separator with a chip bonding layer in the same manner as in Example 1, the PET separator is removed from the cutting tape C to expose one side of the adhesive layer. Using a laminator, the PET separator with the chip bonding layer is bonded to the cutting tape C at room temperature with the exposed side of the chip bonding layer against the exposed side of the adhesive layer, thereby obtaining the cut chip bonding film C.

[0297] [Example 4]

[0298] <Making of Cutting Strips>

[0299] In the same reaction vessel as described in Example 1, 16 parts by mass of HEA as monomers, 84 parts by mass of INA, and 0.2 parts by mass of AIBN as a thermal polymerization initiator were added. Then, butyl acetate as a reaction solvent was added at a concentration of 32% of the aforementioned monomers. The polymerization was carried out at 62°C for 4 hours under a nitrogen gas flow and then at 75°C for 2 hours to obtain acrylic polymer D.

[0300] Add 17 parts by mass of MOI and 0.12 parts by mass of dibutyltin dilaurate to the acrylic polymer D, and carry out an addition reaction at 50°C for 12 hours under an air flow to obtain acrylic polymer D'.

[0301] Next, relative to 100 parts by weight of acrylic polymer D, 0.8 parts by weight of a polyisocyanate compound (trade name "CORONATE L", manufactured by Nippon Polyurethane Co., Ltd.) as an external crosslinking agent, 2 parts by weight of a photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.), and 0.01 parts by weight of an antioxidant (trade name "Irganox 1010", manufactured by BASF JAPAN) were added to prepare an adhesive solution (hereinafter sometimes referred to as adhesive solution D).

[0302] Next, adhesive solution D was applied using an applicator to the silicone-treated surface of the PET release liner (50 μm thick), which had undergone silicone release treatment. The surface was dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Subsequently, a polyolefin film (trade name "FUNCRARENED#125", 125 μm thick) manufactured by Gunze was adhered to this adhesive layer as a substrate layer and stored at 50°C for 24 hours to obtain the cutting tape D.

[0303] <Fabrication of Chip Bonding Layer>

[0304] Prepared in the same manner as in Example 1.

[0305] <Fabrication of chip bonding films>

[0306] After obtaining a 330mmφ PET separator with a chip bonding layer in the same manner as in Example 1, the PET separator is removed from the cutting tape D to expose one side of the adhesive layer. Using a laminator, the PET separator with the chip bonding layer is bonded to the cutting tape D at room temperature with the exposed side of the chip bonding layer abutting against the exposed side of the adhesive layer, thereby obtaining the chip bonding film D.

[0307] [Example 5]

[0308] <Making of Cutting Strips>

[0309] In the same reaction vessel as described in Example 1, 9 parts by mass of HEA as a monomer, 91 parts by mass of lauryl acrylate (hereinafter referred to as LA), and 0.2 parts by mass of AIBN as a thermal polymerization initiator were added. Then, butyl acetate as a reaction solvent was added at a concentration of 30% of the aforementioned monomers. The polymerization was carried out at 62°C for 4 hours under a nitrogen gas flow and then at 75°C for 2 hours to obtain acrylic polymer E.

[0310] Add 10 parts by mass of MOI and 0.21 parts by mass of dibutyltin dilaurate to the acrylic polymer E, and carry out an addition reaction at 50°C for 12 hours under an air flow to obtain acrylic polymer E'.

[0311] Next, relative to 100 parts by weight of acrylic polymer E, 0.8 parts by weight of a polyisocyanate compound (trade name "CORONATE L", manufactured by Nippon Polyurethane Co., Ltd.) as an external crosslinking agent, 2 parts by weight of a photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.), 0.01 parts by weight of an antioxidant (trade name "Irganox 1010", manufactured by BASF JAPAN) and 5 parts by weight of a terpene phenolic resin (trade name "YS Polystar S145", manufactured by Yasuhara Chemical Co., Ltd.) as a tackifier were added to prepare an adhesive solution (hereinafter also referred to as adhesive solution E).

[0312] Next, adhesive solution E was applied using an applicator to the silicone-treated surface of the PET release liner (50 μm thick), which had undergone silicone release treatment. The surface was dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Subsequently, a polyolefin film (trade name "FUNCRARENED#125", 125 μm thick) manufactured by Gunze was adhered to this adhesive layer as a substrate layer and stored at 50°C for 24 hours to obtain the cutting tape E.

[0313] <Fabrication of Chip Bonding Layer>

[0314] Prepared in the same manner as in Example 1.

[0315] <Fabrication of chip bonding films>

[0316] After obtaining a 330mmφ PET separator with a chip bonding layer in the same manner as in Example 1, the PET separator is removed from the cutting tape E to expose one side of the adhesive layer. Using a laminator, the PET separator with the chip bonding layer is bonded to the cutting tape E at room temperature with the exposed side of the chip bonding layer abutting against the exposed side of the adhesive layer, thereby obtaining the chip bonding film E.

[0317] [Example 6]

[0318] <Making of Cutting Strips>

[0319] In the same reaction vessel as described in Example 1, 9 parts by mass of HEA as monomer, 91 parts by mass of LA, and 0.2 parts by mass of AIBN as thermal polymerization initiator were added. Then, butyl acetate as reaction solvent was added at a concentration of 34% of the aforementioned monomers. The polymerization was carried out at 62°C for 4 hours under a nitrogen gas flow and then at 75°C for 2 hours to obtain acrylic polymer F.

[0320] Add 10 parts by mass of MOI and 0.08 parts by mass of dibutyltin dilaurate to the acrylic polymer F, and carry out an addition reaction at 50°C for 12 hours under an air flow to obtain acrylic polymer F'.

[0321] Next, relative to 100 parts by weight of acrylic polymer F, 0.8 parts by weight of a polyisocyanate compound (trade name "CORONATE L", manufactured by Nippon Polyurethane Co., Ltd.) as an external crosslinking agent, 2 parts by weight of a photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.), and 0.01 parts by weight of an antioxidant (trade name "Irganox 1010", manufactured by BASF JAPAN) were added to prepare an adhesive solution (hereinafter also referred to as adhesive solution F).

[0322] Next, adhesive solution F was applied using an applicator to the silicone-treated surface of the PET release liner (50 μm thick), which had undergone silicone release treatment. The surface was dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Subsequently, a polyolefin film (trade name "FUNCRARENED#125", 125 μm thick) manufactured by Gunze was adhered to this adhesive layer as a substrate layer and stored at 50°C for 24 hours to obtain the cutting tape F.

[0323] <Fabrication of Chip Bonding Layer>

[0324] Prepared in the same manner as in Example 1.

[0325] <Fabrication of chip bonding films>

[0326] After obtaining a 330mmφ PET separator with a chip bonding layer in the same manner as in Example 1, the PET separator is removed from the cutting tape F to expose one side of the adhesive layer. Using a laminator, the PET separator with the chip bonding layer is bonded to the cutting tape F at room temperature with the exposed side of the chip bonding layer abutting against the exposed side of the adhesive layer, thereby obtaining the chip bonding film F.

[0327] [Comparative Example 1]

[0328] <Making of Cutting Strips>

[0329] In the same reaction vessel as described in Example 1, 19 parts by mass of HEA as a monomer, 81 parts by mass of ethyl acrylate (hereinafter referred to as EA), and 0.2 parts by mass of AIBN as a thermal polymerization initiator were added. Then, butyl acetate as a reaction solvent was added at a concentration of 42% of the aforementioned monomers. The polymerization was carried out at 62°C for 4 hours under a nitrogen gas flow and then at 75°C for 2 hours to obtain acrylic polymer G.

[0330] Add 21 parts by mass of MOI and 0.03 parts by mass of dibutyltin dilaurate to the acrylic polymer G, and carry out an addition reaction at 50°C for 12 hours under an air flow to obtain acrylic polymer G'.

[0331] Next, relative to 100 parts by weight of acrylic polymer G, 0.8 parts by weight of a polyisocyanate compound (trade name "CORONATE L", manufactured by Nippon Polyurethane Co., Ltd.) as an external crosslinking agent, 2 parts by weight of a photopolymerization initiator (trade name "Omnirad 127", manufactured by IGM Resins Co., Ltd.), and 0.01 parts by weight of an antioxidant (trade name "Irganox 1010", manufactured by BASF JAPAN) were added to prepare an adhesive solution (hereinafter sometimes referred to as adhesive solution G).

[0332] Next, adhesive solution G was applied using an applicator to the silicone-treated surface of the PET release liner (50 μm thick), which had undergone silicone release treatment. The surface was dried at 120°C for 2 minutes to form an adhesive layer with a thickness of 10 μm. Subsequently, a polyolefin film (trade name "FUNCRARENED#125", 125 μm thick) manufactured by Gunze was adhered to this adhesive layer as a substrate layer and stored at 50°C for 24 hours to obtain the cutting tape G.

[0333] <Fabrication of Chip Bonding Layer>

[0334] Prepared in the same manner as in Example 1.

[0335] <Fabrication of chip bonding films>

[0336] After obtaining a 330mmφ PET separator with a chip bonding layer in the same manner as in Example 1, the PET separator is removed from the cutting tape G to expose one side of the adhesive layer. Using a laminator, the PET separator with the chip bonding layer is bonded to the cutting tape G at room temperature with the exposed side of the chip bonding layer abutting against the exposed side of the adhesive layer, thereby obtaining the chip bonding cut film G.

[0337] (Mass ratio of sol components)

[0338] For the adhesive layer before curing of the die-cutting bonding film in each example, the mass ratio of the sol component is determined by following the steps below.

[0339] (1) Take a sample of about 0.2g from the adhesive layer before curing.

[0340] (2) After wrapping the aforementioned sample with a mesh sheet, it was immersed in about 30 mL of toluene for 1 week at room temperature.

[0341] (3) Remove the mesh sheet from the toluene and remove the toluene-insoluble components contained in the mesh sheet.

[0342] (4) After drying the aforementioned toluene-insoluble component at atmospheric pressure and 130°C for about 2 hours, weigh the aforementioned toluene-insoluble component.

[0343] (5) Calculate the mass ratio of the gel component according to the following formula (1), and calculate the mass ratio of the sol component according to the following formula (2) based on the calculated value of the mass ratio of the gel rate.

[0344] The results are shown in Table 2 below.

[0345] The mass ratio of the gel component (mass%) = [(weighed value of the toluene-insoluble component) / mass of the sample taken] × 100···(1)

[0346] Mass ratio of sol component (mass%) = 100 - Mass ratio of gel component obtained from formula (1) above...(2)

[0347] (GPC measurement)

[0348] For the adhesive layer of the die-cutting bonding film before curing in each example, the HLC-8220GPC manufactured by Tosoh Corporation was used as the analytical device. GPC determination was performed according to the following steps, and the results of the GPC determination obtained according to the following steps were analyzed to obtain information about the molecular weight.

[0349] [Preparation of the test sample]

[0350] (1) Take a sample of about 0.2g from the adhesive layer 2 before curing.

[0351] (2) After wrapping the aforementioned sample with a mesh sheet, it was immersed in about 30 mL of toluene for 1 week at room temperature.

[0352] (3) Remove the mesh sheet from the toluene, remove the toluene-insoluble components contained in the mesh sheet, and obtain a toluene solution containing toluene-soluble components.

[0353] (4) The aforementioned toluene solution was treated under reduced pressure at a temperature below 45°C to remove toluene from the aforementioned toluene solution and obtain a solid substance containing the dissolved toluene components.

[0354] (5) Dissolve the aforementioned solid substance in tetrahydrofuran (THF) to a concentration of 0.2% by mass to prepare a THF solution, and then let it stand overnight.

[0355] (6) The THF solution that had been left overnight was filtered through a 0.45 μm membrane filter, and the resulting filtrate was used as the test sample.

[0356] [Measurement Conditions]

[0357] • Pillar: One TSKgel quaudcolumn SuperHZ-L (hereinafter referred to as Pillar 1) manufactured by Tosoh Corporation, and

[0358] Two TSKgel SuperHZM-M (hereinafter referred to as the second column) manufactured by Tosoh Corporation

[0359] The aforementioned columns are arranged in the aforementioned analytical apparatus such that two of the aforementioned second columns are connected in series on the downstream side of the aforementioned first column, and the eluent, described later, flows in from the side of the aforementioned first column.

[0360] Column temperature: 40℃

[0361] • Eluent: Tetrahydrofuran (THF)

[0362] • Flow rate: Sample pump flow rate 0.3 mL / min

[0363] Reference pump flow rate: 1.0 mL / min

[0364] Injection volume: 10μL

[0365] • Detector: Differential Refractive Index Detector (RI)

[0366] In addition, in order to obtain a molecular weight distribution curve based on the results obtained from the aforementioned test samples, each standard polystyrene manufactured by Tosoh Corporation was measured in a manner that resulted in the mixed mass shown in Table 1 above. Each measured standard polystyrene was dissolved in 100 mL of THF to obtain standard polystyrene solution STD1 and standard polystyrene solution STD2. These solutions were also subjected to GPC determination using the aforementioned measuring apparatus under the aforementioned measuring conditions.

[0367] The results obtained from GPC measurements of the aforementioned test samples, STD1, and STD2 were analyzed using GPC-8020 Model II (Data Management Version 5.10) software manufactured by Tosoh Corporation.

[0368] In the data analysis using the aforementioned analysis software, firstly, calibration curves for STD1 and STD2 are constructed (calibration curves with time (minutes) on the horizontal axis and the logarithm of weight-average molecular weight on the vertical axis). Data analysis of the molecular weight of the aforementioned test samples is then performed based on these calibration curves. The molecular weight analysis of the aforementioned test samples is conducted based on the molecular weight distribution curve of the earliest detected peak P1 (the peak on the highest molecular weight side) on the chromatogram. By analyzing the molecular weight distribution curve of peak P1, the number-average molecular weight Mn and weight-average molecular weight Mw of peak P1 can be obtained.

[0369] It should be noted that the test samples obtained from the adhesive layer of the chip bonding film in each example all showed overlap in the descending portion of the earliest detected peak P1 and the ascending portion of the peak P2 detected after peak P1. Therefore, a baseline was drawn with the starting portion of the ascending peak P1 as the base point and extended horizontally. A vertical line was drawn from the aforementioned baseline to the valley portion (the most concave portion) generated between the descending portion of peak P1 and the ascending portion of peak P2. The region separated by the aforementioned baseline from the starting portion of the ascending peak P1 to the aforementioned valley portion, and the line drawn vertically from the aforementioned baseline to the aforementioned valley portion was analyzed. Thus, the number-average molecular weight Mn and weight-average molecular weight Mw of peak P1 can be obtained.

[0370] Table 2 below shows the number-average molecular weight Mn of peak P1, the weight-average molecular weight Mw of peak P1, and the ratio of the weight-average molecular weight Mw of peak P1 to the number-average molecular weight Mn of peak P1.

[0371] In addition, the peak molecular weight of peak P1 is shown in Table 2 below.

[0372] (Transfer ratio of photopolymerization initiator)

[0373] For each example of diced chip bonding film, the transfer rate of photopolymerization initiator from the adhesive layer to the chip bonding layer was determined.

[0374] The transfer ratio of the photopolymerization initiator is calculated from the mass ratio of the photopolymerization initiator contained in the sample taken from the adhesive layer portion that does not overlap with the chip bonding layer (first mass ratio) and the mass ratio of the photopolymerization initiator contained in the sample taken from the chip bonding layer portion that overlaps with the adhesive layer (second mass ratio).

[0375] The aforementioned first mass ratio is determined by the following steps.

[0376] (1) For each example of the die bonding film, take about 0.1g of the adhesive layer portion that is not stacked with the die bonding layer and is more than 1cm away from the die bonding layer.

[0377] (2) After adding the adhesive layer to 4 mL of chloroform, shake it in the dark overnight (about 16 hours) to extract the photopolymerization initiator in the adhesive layer from the chloroform.

[0378] (3) Add 7 mL of methanol to the chloroform solution after the photopolymerization initiator is extracted to allow the components other than the photopolymerization initiator to redeprecipitate. Filter the redeprecipitated components using a membrane filter to obtain a solution of the photopolymerization initiator (a mixed solution of chloroform and methanol). Use this solution as the test sample.

[0379] (4) The aforementioned test sample was analyzed by HPLC to determine the concentration of the aforementioned photopolymerization initiator in the aforementioned test sample (in μg / mL).

[0380] (5) Multiply the concentration of the aforementioned photopolymerization initiator by the volume of the mixed solvent (a mixture of chloroform and methanol) containing the aforementioned photopolymerization initiator (11 mL) to calculate the mass (in μg) of the aforementioned photopolymerization initiator in the aforementioned test sample.

[0381] (6) The mass ratio of the aforementioned photopolymerization initiator in the adhesive layer is calculated by dividing the mass of the aforementioned photopolymerization initiator in the aforementioned test sample by the mass of the adhesive layer taken, and this ratio is taken as the first mass ratio.

[0382] The aforementioned second mass ratio is determined by the following steps. It should be noted that steps (1) to (4) are all performed in the dark.

[0383] (1) Peel off about 0.1g of the chip bonding layer from the adhesive layer.

[0384] (2) After adding the stripped chip bonding layer to 4 mL of chloroform, shake it in the dark overnight (about 16 hours) to extract the photopolymerization initiator in chloroform.

[0385] (3) Add 7 mL of methanol to the chloroform solution after the photopolymerization initiator is extracted to allow the components other than the photopolymerization initiator to redeprecipitate. Filter the redeprecipitated components using a membrane filter to obtain a solution of the photopolymerization initiator (a mixed solution of chloroform and methanol). Use this solution as the test sample.

[0386] (4) The aforementioned test sample was analyzed by HPLC to determine the concentration of the aforementioned photopolymerization initiator in the aforementioned test sample (in μg / mL).

[0387] (5) Multiply the concentration of the aforementioned photopolymerization initiator by the volume of the mixed solvent (a mixture of chloroform and methanol) containing the aforementioned photopolymerization initiator (11 mL) to calculate the mass (in μg) of the aforementioned photopolymerization initiator in the aforementioned test sample.

[0388] (6) The mass ratio of the aforementioned photopolymerization initiator in the aforementioned chip bonding layer is calculated by dividing the mass of the aforementioned photopolymerization initiator in the aforementioned test sample by the mass of the chip bonding layer taken, and this ratio is taken as the second mass ratio.

[0389] It should be noted that the HPLC analysis was performed under the following conditions.

[0390] Analytical device

[0391] Waters, Acquity HPLC

[0392] Measurement conditions

[0393] • Standard solutions: Three solutions were prepared by dissolving Omnirad at a concentration of 5.54 μg / mL in a mixture of chloroform and methanol (Standard Solution 1); a solution prepared by dissolving Omnirad at a concentration of 55.4 μg / mL in a mixture of chloroform and methanol (Standard Solution 2); and a solution prepared by dissolving Omnirad at a concentration of 166.2 μg / mL in a mixture of chloroform and methanol (Standard Solution 3).

[0394] • Column: GL Science, Inertsil (registered trademark) (2.1mm φ × 10cm, average particle size of the carrier 1.7μm)

[0395] Column temperature: 40℃

[0396] • Column flow rate: 0.8 mL / min

[0397] • Eluent composition: Gradient conditions of ultrapure water / acetonitrile

[0398] Injection volume: 10μL

[0399] • Detector: PDA detector

[0400] • Detection wavelength: 260nm

[0401] Substituting the values ​​of the first and second mass ratios mentioned above into equation (3) below, the transfer ratio of the photopolymerization initiator is calculated. The results are shown in Table 2 below.

[0402] The transfer rate (mass%) of the photopolymerization initiator = -second mass ratio / first mass ratio × 100 (3)

[0403] (Peeling force)

[0404] For each example of diced chip bonding film, the peel force of the chip bonding layer relative to the adhesive layer was measured. The peel force of the chip bonding layer relative to the adhesive layer was measured after the adhesive layer had cured.

[0405] The peel force of the chip bonding layer relative to the adhesive layer is determined using a T-type peel test.

[0406] The T-type peel test is performed as follows: The PET separator is peeled off from the chip bonding layer, forming an exposed surface on the chip bonding layer. For the die-cutting bonding film with a backing tape (trade name "ELP BT315", manufactured by Nitto Denko Corporation) bonded to this exposed surface, a Nitto Seiki "UM-810" high-pressure mercury lamp (60mW / cm²) is used. 2 Irradiation intensity from the cutting strip side: 150 J / cm 2 After the adhesive layer is cured by ultraviolet light, it is cut into a size of 50mm wide × 120mm long and used as a test sample. The test is performed using a tensile tester (e.g., "TG-1kN", manufactured by MinebeaMitsumi Inc.) at a temperature of 25°C and a tensile speed of 300mm / min.

[0407] The peel force measured by the above operation is shown in Table 2 below.

[0408] (Pickup)

[0409] For a diced semiconductor chip with a chip bonding layer, the pick-up capability is evaluated. The diced semiconductor chip with a chip bonding layer is obtained as follows: On a 12-inch bare wafer (300mm diameter, 55μm thickness) with dicing grooves (10mm x 10mm) formed by half-cutting, a back-grinding tape is attached to the surface with the dicing grooves. Then, using a back-grinding machine (DISCO, model DGP8760), the 12-inch bare wafer is ground from the side opposite to the side with the attached back-grinding tape until a thickness of 25μm is obtained, resulting in a back-grinded bare wafer. A chip bonding layer of various diced chip bonding films is attached to the side of the back-grinded bare wafer opposite to the side with the back-grinding tape, resulting in a bare wafer with a diced chip bonding film. This bare wafer with the diced chip bonding film is then expanded using a chip separator (trade name "Die separator DDS3200, DISCO"), thereby obtaining the desired chip bonding layer.

[0410] It should be noted that the expansion using the chip separation device was carried out with the aforementioned back-side polishing tape stripped from the bare wafer.

[0411] In the expansion process using a chip separation device, cold expansion is performed followed by room temperature expansion.

[0412] Cold spreading is performed as follows: A 12-inch diameter SUS ring frame (manufactured by DISCO) is attached to the frame bonding area on the adhesive layer of the die bonding film attached to the bare wafer at room temperature. The bare wafer with the SUS ring frame attached is then mounted on a die separation device, and the dicing strip of the die bonding film is spread using the cold spreading unit of this device. Cold spreading is performed at a spreading temperature of -15°C, a spreading speed of 100 mm / s, and a spreading amount of 7 mm.

[0413] It should be noted that after cold expansion, while the semiconductor wafer is monolithically divided into multiple semiconductor chips, the chip bonding layer is also monolithically divided into a size equivalent to that of the semiconductor chip, resulting in multiple semiconductor chips with chip bonding layers.

[0414] Room temperature spreading is performed by spreading the diced strip of the die bonding film using the room temperature spreading unit of the aforementioned die separation device after cold spreading. The room temperature spreading is carried out at a spreading temperature of 23±2℃, a spreading speed of 1mm / second, and a spreading amount of 10mm.

[0415] For the cut strip that has been expanded at room temperature, a heat shrinking treatment is performed. The heat shrinking treatment is carried out at a temperature of 200℃ for 20 seconds.

[0416] After the dicing tape is heated and shrunk, a pick-up test is performed on the monolithic semiconductor chip with a chip bonding layer using a device with a pick-up mechanism (trade name "Die bonder SPA-300", manufactured by Shinkawa). In the device with the aforementioned pick-up mechanism, the lifting speed of the pin member is set to 1 mm / s and the lifting amount is set to 2000 μm.

[0417] The aforementioned pickup test used the Nitto Seiki brand product "UM-810" (high-pressure mercury lamp, 60mW / cm²). 2 Irradiation intensity from the cutting strip side: 150 J / cm 2 The process is carried out after the adhesive layer has been cured by ultraviolet light.

[0418] Pickup tests were performed on five semiconductor chips with chip bonding layers. Pickup performance was judged according to the following criteria.

[0419] ◎All five semiconductor chips with chip bonding layers can be picked up.

[0420] Of the 5 semiconductor chips with chip bonding layers, 3 or 4 can be picked up.

[0421] All five semiconductor chips with chip bonding layers could not be picked up.

[0422] [Table 2]

[0423]

[0424] As shown in Table 2, compared with the chip bonding film of Comparative Example 1, the chip bonding films of Examples 1 to 6 have a lower rate of photopolymerization initiator transfer from the adhesive layer to the chip bonding layer, and the adhesion strength after radiation irradiation is also significantly reduced.

[0425] Furthermore, regarding pick-up performance, the chip bonding films of Examples 1-6 are 0 or ◎, which is good, while the chip bonding film of Comparative Example 1 is ×, which is bad.

Claims

1. A chip-cutting bonding film, comprising: A cut strip with an adhesive layer laminated on top of the substrate layer, and A chip bonding layer is stacked on the adhesive layer of the cutting strip; The adhesive layer comprises an adhesive and a photopolymerization initiator. In the molecular weight distribution curve obtained by GPC measurement of the adhesive layer before curing, the ratio of the weight average molecular weight Mw of the peak appearing on the highest molecular weight side to the number average molecular weight Mn of the peak appearing on the highest molecular weight side, i.e., the polydispersity Mw / Mn, is 2.0 or higher. The adhesive layer before curing contains less than 23% by mass of sol component.

2. The chip bonding film according to claim 1, wherein, In the molecular weight distribution curve obtained by GPC measurement of the adhesive layer before curing, the peak molecular weight of the peak appearing on the highest molecular weight side is below 33,000.

3. The chip-cutting bonding film according to claim 1 or 2, wherein, After the adhesive layer has cured, the peel force of the chip bonding layer relative to the adhesive layer is less than 0.18 N / 20 mm.

Images