Adhesive tape for processing electronic components and method for manufacturing electronic components

Abstract

To provide an adhesive tape for processing electronic components that has good expandability and is capable of suppressing misalignment during dicing.SOLUTION: An adhesive tape 10 for processing electronic components includes: a resin film 1 having a first surface S1 and a second surface S2 facing the first surface, the resin film 1 having an air blocking property in a surface direction and having a through hole 1h penetrating in a thickness direction; and an adhesive layer 2 arranged in the first surface of the resin film 1 and having a non-porous structure. The elongation at breakage of the adhesive tape 10 for processing electronic components is at least 100%.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an adhesive tape for processing electronic components and a method for manufacturing electronic components. [Background technology]

[0002] Conventionally, substrates to be processed are divided into chips in a dicing process. The dicing process places stress on the chips, which can lead to issues of reduced yield and quality. In recent years, as electronic devices have become more sophisticated, chips have become smaller, thinner, and more highly integrated. As a result, the problems of reduced yield and reduced quality have become more pronounced.

[0003] In recent years, a dicing method using a laser guided by a water jet has been proposed. This method is hereinafter referred to as water jet laser dicing. Water jet laser dicing offers the following advantages: It significantly reduces the mechanical load on the substrate. Therefore, chipping and microcracks are less likely to occur. Because the water jet is used as a guide and the substrate is cooled with water during dicing, thermal load is reduced despite the use of a laser. This reduces heat-related quality degradation. Compared to blade dicing, it uses less water, resulting in less wastewater. It significantly increases the processing speed, shortening processing time and reducing the load. Compared to laser dicing, dicing is performed within the stable range of the water jet, eliminating the need for focal position adjustment. Because the laser is guided by the water jet, the cut surface is perpendicular. This improves reliability. Therefore, it can also be applied to automotive semiconductors. It also allows for narrower chip spacing. The deep depth of focus allows for processing of thick substrates. It is possible to process substrates made of hard materials such as SiC. Therefore, it can also be applied to power semiconductors. It is also possible to process the substrate into a curved shape. The surface of the substrate is protected by water, so there is little adhesion to the surface. This simplifies cleaning work. After penetrating the substrate, the water jet can be used to remove processing debris, so there are fewer burrs on the backside. In this way, water jet laser processing is advantageous for making chips smaller, thinner, and more highly integrated, and is advantageous for improving yield and quality.

[0004] In the dicing process, an adhesive tape called dicing tape is used to protect and secure the substrate and chips. Adhesive tape typically has a substrate and an adhesive layer. In the case of water jet laser processing, if the substrate is impermeable to water, chipping and chipping due to water splashing are likely to occur. Therefore, as described in Patent Documents 1 and 2, for example, porous substrates such as woven or nonwoven fabrics that are permeable to water are used as the substrate for the adhesive tape in water jet laser processing. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-117943 [Patent Document 2] Patent No. 4128843 [Patent Document 3] Patent No. 3824874 [Patent Document 4] Japanese Patent Application Laid-Open No. 2008-60170 Summary of the Invention [Problem to be solved by the invention]

[0006] The adhesive tape is attached to a ring frame, and the substrate to be processed is fixed onto the adhesive tape. In the dicing process, the substrate to be processed, which is fixed to the adhesive tape, is then sucked and fixed onto a suction table for processing.

[0007] The inventors of the present disclosure have discovered a new problem: although adhesive tapes having a porous substrate can suppress chipping and chip flying due to water splashing by allowing water to pass through the porous substrate, gaps may occur between the surface of the adhesive tape facing the porous substrate and the suction table, and air leakage from these gaps reduces the suction force of the suction table, causing misalignment during dicing. As described above, with the recent trend toward smaller, thinner, and more highly integrated chips, high accuracy is required for the accuracy of misalignment of the cutting position during dicing.

[0008] In the method for manufacturing electronic components, the dicing step is followed by an expanding step in which the adhesive tape is stretched to increase the spacing between chips, and a pick-up step in which the chips are picked up from the adhesive tape.

[0009] However, when a porous substrate is used as the base material for an adhesive tape, there is a problem in that the spacing between chips cannot be sufficiently widened because many porous substrates generally have poor expandability, making it difficult to pick up the chips.

[0010] The present disclosure has been made in consideration of the above-described circumstances, and has as its main object to provide an adhesive tape for processing electronic components that has good expandability and can suppress misalignment during dicing. [Means for solving the problem]

[0011] One embodiment of the present disclosure provides an adhesive tape for electronic component processing, comprising: a resin film having a first surface and a second surface opposite the first surface, being non-breathable in the plane direction and having through holes penetrating in the thickness direction; and an adhesive layer having a non-porous structure, disposed on the first surface of the resin film, wherein the adhesive tape for electronic component processing has an elongation at break of 100% or more.

[0012] Another embodiment of the present disclosure provides a method for manufacturing electronic components, including an application step of applying the above-mentioned adhesive tape for electronic component processing to a first surface of a substrate to be processed, a dicing step of dividing the substrate to be processed into a plurality of chips, an expanding step of stretching the adhesive tape for electronic component processing to increase the spacing between the chips, and a pick-up step of picking up the chips from the adhesive tape for electronic component processing. [Effects of the Invention]

[0013] The present disclosure can provide an adhesive tape for processing electronic components that has good expandability and can suppress misalignment during dicing. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a schematic cross-sectional view illustrating an example of an adhesive tape for processing electronic components according to the present disclosure. [Figure 2]1A to 1C are process diagrams illustrating a dicing process using an adhesive tape for processing electronic components according to the present disclosure. [Figure 3] 1A to 1C are process diagrams illustrating a conventional dicing process using an adhesive tape. [Figure 4] 1A to 1C are process diagrams illustrating a conventional dicing process using an adhesive tape. [Figure 5] 1A to 1C are process diagrams illustrating a dicing process using an adhesive tape for processing electronic components according to the present disclosure. [Figure 6] 1A to 1C are process diagrams illustrating a method for manufacturing an electronic component according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0015] Embodiments of the present disclosure will be described below with reference to the drawings and the like. However, the present disclosure can be implemented in many different forms and should not be limited to the description of the embodiments exemplified below. Furthermore, in order to clarify the description, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the actual form, but these are merely examples and should not be interpreted as being limiting. Furthermore, in this specification and each drawing, elements similar to those described above with reference to the previous drawings will be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0016] In this specification, when describing a mode in which another component is placed on a certain component, the term "above" or "below" includes, unless otherwise specified, both a case in which another component is placed directly above or below a certain component so as to be in contact with the component, and a case in which another component is placed above or below a certain component with another component interposed therebetween. Also, in this specification, when describing a mode in which another component is placed on the surface of a certain component, the term "on the surface" includes, unless otherwise specified, both a case in which another component is placed directly above or below a certain component so as to be in contact with the component, and a case in which another component is placed above or below a certain component with another component interposed therebetween.

[0017] In this specification, the terms "film" and "sheet" are not distinguished from each other solely based on the difference in name.

[0018] The adhesive tape for processing electronic components and the method for manufacturing electronic components according to the present disclosure will be described below.

[0019] A. Adhesive tape for electronic component processing The adhesive tape for electronic component processing according to the present disclosure comprises a resin film having a first surface and a second surface opposite to the first surface, being non-breathable in the surface direction and having through holes penetrating in the thickness direction, and an adhesive layer having a non-porous structure disposed on the first surface of the resin film, and the adhesive tape for electronic component processing has an elongation at break of 100% or more.

[0020] Fig. 1 is a schematic cross-sectional view illustrating an example of an adhesive tape for electronic component processing according to the present disclosure. As illustrated in Fig. 1, the adhesive tape for electronic component processing 10 includes a resin film 1 that is non-breathable in a plane direction D1 and has through-holes 1h penetrating in a thickness direction D2, and an adhesive layer 2 that is disposed on a first surface S1 of the resin film 1 and has a non-porous structure.

[0021] 2(a) and 2(b) are process diagrams illustrating an example of a dicing process using an adhesive tape for electronic component processing according to the present disclosure. First, as shown in FIG. 2(a), a ring frame 21 is attached to the surface of the adhesive layer 2 of the adhesive tape for electronic component processing 10, and a workpiece substrate 11 is attached to the surface of the adhesive layer 2 of the adhesive tape for electronic component processing 10, thereby fixing the workpiece substrate 11 to the adhesive tape for electronic component processing 10. Next, the workpiece substrate 11 fixed to the adhesive tape for electronic component processing 10 is fixed to a suction table 22 by vacuum suction. Next, as shown in FIG. 2(b), the workpiece substrate 11 is divided into chips 12.

[0022] FIG. 3 is a schematic cross-sectional view illustrating a case where a workpiece substrate is adsorbed and fixed to a suction table during a dicing process using a conventional adhesive tape having a porous substrate. As shown in FIG. 3, an adhesive tape 100A has a porous substrate 101 and an adhesive layer 102. In FIG. 3, the porous substrate 101 is a woven fabric. When such an adhesive tape 100A is used, the surface of the woven porous substrate 101 is uneven, resulting in a gap between the surface of the adhesive tape 100A facing the porous substrate 101 and the suction table 22. Air leakage from this gap reduces the suction force of the suction table 22. This problem is not limited to when the porous substrate 101 is a woven fabric; a similar problem occurs when the porous substrate 101 is a cloth such as a woven fabric, nonwoven fabric, or knitted fabric. Furthermore, when the porous substrate 101 is a cloth, the porous substrate 101 typically has air permeability in the planar direction. Therefore, air leaks from the end face of the porous substrate 101 or leaks from the cut portion 13 of the workpiece substrate 11 through the porous substrate 101, thereby reducing the suction force of the suction table 22. In this way, the inventors of the present disclosure discovered a new problem with conventional adhesive tapes having porous substrates: air leakage reduces the suction force of the suction table, causing misalignment during dicing.

[0023] Patent Document 4 also discloses an adhesive tape having a base material and an adhesive layer, the adhesive tape having through-holes penetrating in the thickness direction. FIG. 4 is a schematic cross-sectional view illustrating a case in which such an adhesive tape is used to suction-fix a workpiece substrate to a suction table during a dicing process. When such an adhesive tape 100B is used, the adhesive tape 100B has through-holes 100h, which allow air to leak from the through-holes 100h in areas of the adhesive tape 100B where the workpiece substrate 11 is not attached. Air also leaks from the cut portion 13 of the workpiece substrate 11 through the through-holes 100h. This significantly reduces the suction force of the suction table 22. This makes it difficult to fix the workpiece substrate 11 fixed to the adhesive tape 100B to the suction table 22.

[0024] FIG. 5 is a schematic cross-sectional view illustrating a case where a workpiece substrate is suction-fixed to a suction table during a dicing process using an adhesive tape for electronic component processing according to the present disclosure. In FIG. 5, in the adhesive tape for electronic component processing 10, the resin film 1 is non-breathable in the planar direction, thereby preventing air leakage from the end face of the resin film 1. Furthermore, although the resin film 1 has through-holes 1h, the adhesive layer 2 has a non-porous structure, and the through-holes 1h are covered by the adhesive layer 2. This prevents air leakage from the through-holes 1h even in areas of the adhesive tape for electronic component processing 10 where the workpiece substrate 11 is not attached. Furthermore, air leakage from the cut portion 13 of the workpiece substrate 11 through the through-holes 1h is also prevented. This prevents a decrease in the suction force of the suction table due to air leakage, thereby preventing misalignment during dicing. Specifically, it prevents misalignment of the cutting position during dicing.

[0025] In addition, in the present disclosure, the resin film having through-holes can be formed by punching or laser processing of the resin film, or mold printing using gravure printing, as described below. Therefore, unlike conventional porous substrates such as woven fabrics, nonwoven fabrics, and knitted fabrics, the formation of a gap between the resin film side of the adhesive tape for electronic component processing and the suction table during the dicing process can be suppressed. Therefore, the adhesive tape for electronic component processing attached to the substrate to be processed can be firmly fixed to the suction table, suppressing misalignment during dicing.

[0026] Therefore, the pressure-sensitive adhesive tape for electronic component processing according to the present disclosure can be suitably used when dicing a substrate to be processed by water jet laser processing.

[0027] In recent years, with the increasing sophistication of electronic devices, wafers have become thinner and chips have become smaller, thinner, and more highly integrated, resulting in a decrease in chip strength. Therefore, from the viewpoint of pickup performance, it is desirable to sufficiently widen the chip spacing in the expanding step, i.e., to sufficiently expand the adhesive tape for processing electronic components.

[0028] In the present disclosure, the elongation at break of the adhesive tape for electronic component processing is equal to or greater than a predetermined value, so that the chip spacing can be sufficiently widened in the expanding process. Furthermore, in the pick-up process, the adhesive tape for electronic component processing is pushed up and expanded by a needle, block, or the like, and the adhesive tape for electronic component processing can be sufficiently expanded during this process. Therefore, interference between chips can be suppressed, and chipping can be suppressed. Therefore, the chip processing accuracy and yield can be improved.

[0029] Hereinafter, each component of the adhesive tape for processing electronic components according to the present disclosure will be described.

[0030] 1. Resin film The resin film in the present disclosure is a member that is non-breathable in the plane direction, has through-holes that penetrate through in the thickness direction, and supports the adhesive layer.

[0031] (1) Characteristics of resin film (a) Non-breathable The resin film is non-breathable in the in-plane direction. The non-breathability of the resin film in the in-plane direction can be confirmed using the following method. First, a resin film is cut into a 210 mm x 210 mm size to obtain a test piece. The resin film is placed on the 200 mm diameter ceramic porous chuck table of a Harmotec tape remover "HTR0608-1." A 50 μm thick polyethylene terephthalate (PET) film is then placed on top of the resin film, and vacuum suction is initiated. During vacuum suction, a ULVAC vacuum pump "DA-20D" is used. While the vacuum is being drawn, the differential pressure between the inside of the ceramic porous chuck table and the atmosphere is measured using a dial-type differential pressure gauge attached to the device. If the differential pressure is -70 kPa or less, the resin film is determined to be non-breathable in the in-plane direction.

[0032] (b) Non-absorption of laser light Some laser beams are easily absorbed by water, while others are not. Therefore, in water jet laser processing, the use of short-wavelength laser beams is being considered to reduce the absorption rate in water and increase processing efficiency.

[0033] However, in general, the shorter the wavelength of the laser beam, the higher the energy and the higher the absorption rate of the laser beam in a material. Therefore, when a short-wavelength laser beam is used in water jet laser processing, the substrate of the adhesive tape may break during the water jet laser processing, or the substrate may become brittle during the water jet laser processing, making the substrate more susceptible to breakage during the expanding step.

[0034] Therefore, it is preferable that the material of the resin film is non-absorbent to laser light. By using a material that is non-absorbent to the laser light used in water jet laser processing, the resin film can be prevented from absorbing the laser light and generating heat. This can prevent the adhesive tape for electronic component processing from breaking during water jet laser processing, or prevent the resin film from becoming brittle during water jet laser processing.

[0035] "Non-absorbent to laser light" refers to being transmissive to or reflective to the wavelength of the laser light used in water jet laser processing. Specifically, when the region on the first surface of the resin film where through holes exist is defined as the through hole region and the region where no through holes exist is defined as the non-penetration region, and the transmittance of the laser light in the non-penetration region of the resin film is defined as T1 (%), it is preferable that the transmittance of the non-penetration region of the resin film in the range of the wavelength λ of the laser light ±20 nm is within T1 ±2.0%. When the transmission spectrum of the non-penetration region of the resin film is obtained based on the transmission spectrum of the entire resin film, if the transmittance in a predetermined wavelength range in the transmission spectrum of the non-penetration region of the resin film satisfies the above relationship, the resin film can be said to be non-absorbent to laser light, i.e., not have an absorption band at the wavelength of the laser light.

[0036] In particular, the material of the resin film is preferably transparent to the wavelength of the laser light used in water jet laser processing. The transmittance T1 of the laser light in the non-penetrating region of the resin film is, for example, 50% or more, or may be 70% or more, or may be 90% or more.

[0037] The transmittance T1 of the laser light through the non-penetrating region of the resin film is calculated by the following formula (1) using the transmittance T2 of the laser light through the resin film and the aperture ratio A of the resin film. T1 = (T2 - A) / (100 - A) × 100 (1)

[0038] The laser light transmittance T2 of the resin film is the laser light transmittance of the entire resin film.

[0039] The aperture ratio A (%) of a resin film is a value obtained by dividing the total area of all through-holes in a measurement region on the first surface of the resin film by the total area of the measurement region. The area of all through-holes in the measurement region is measured by microscopic observation. If the aperture ratio of the resin film is known, that aperture ratio may be used.

[0040] The laser light absorption and non-absorption properties of the resin film can be controlled, for example, by adjusting the material of the resin film.

[0041] When the material of the resin film is non-absorbent to laser light, the resin film may be colorless or colored.

[0042] Examples of wavelengths of laser light used in water jet laser processing include the 1064 nm wavelength of the fundamental wave of a YAG laser, the 532 nm wavelength of the second harmonic of a YAG laser, and the 355 nm wavelength of the third harmonic of a YAG laser. In recent years, in water jet laser processing, the use of laser light with a short wavelength has been considered to reduce the absorption rate in water and increase processing efficiency. Therefore, in the present disclosure, it is preferable to use laser light with a wavelength of 532 nm or 355 nm for non-absorbent or absorbent laser light.

[0043] (c) Load at 100% elongation The load at 100% elongation of the resin film is not particularly limited as long as it satisfies the elongation at break of the adhesive tape for electronic component processing described below, but may be, for example, 50 N or less, or may be 40 N or less, or may be 30 N or less. When the load at 100% elongation of the resin film is within the above range, the expandability can be improved, and the adhesive tape for electronic component processing can be expanded with a low load. On the other hand, the load at 100% elongation of the resin film is, for example, 5 N or more, or may be 10 N or more, or may be 20 N or more. If the load at 100% elongation of the resin film is too low, the flexibility may be too high, making it difficult to perform stable dicing processing. Specifically, the load at 100% elongation of the resin film is, for example, 5 N or more and 50 N or less, or may be 10 N or more and 40 N or less, or 20 N or more and 30 N or less.

[0044] The load at 100% elongation of the resin film is measured in accordance with JIS K7127:1999. Specific measurement conditions are shown below. The tensile tester used is, for example, the "Tensilon RTF1150" manufactured by A&D Co., Ltd.

[0045] <Measurement conditions> Test piece: rectangular test piece (width 10 mm, length 60 mm) ·Distance between gauge lines: 25mm Initial distance between chucks: 25mm Pulling speed: 200mm / min ·Temperature: 23±2℃ ·Humidity: 50±10%RH

[0046] (d) Energy ray transmittance As will be described later, when the adhesive layer is an energy ray-curable adhesive layer, the resin film has through holes, allowing energy rays to pass through. The energy ray transmittance of the resin film is, for example, 50% or more, or may be 70% or more, or 90% or more. When the energy ray transmittance of the resin film is high within the above range, reflection of energy rays by the resin film can be suppressed when the adhesive tape for electronic component processing is irradiated with energy rays from the resin film side to cure the adhesive layer. This can suppress poor curing of the adhesive layer. On the other hand, there is no particular limitation on the upper limit of the energy ray transmittance of the resin film.

[0047] In this specification, the energy ray transmittance refers to the transmittance of the energy ray used when dicing a substrate to be processed using the adhesive tape for electronic component processing. For example, when ultraviolet light is used, and a high-pressure mercury lamp or a light source that reproduces the spectrum of a high-pressure mercury lamp is used, the dominant wavelength of the high-pressure mercury lamp is 365 nm. Therefore, in this case, the energy ray transmittance refers to the transmittance of a wavelength of 365 nm.

[0048] When measuring the properties of the resin film, the adhesive layer is removed from the adhesive tape for electronic component processing, and the resin film is taken out. A method for removing the adhesive layer includes dissolving the adhesive layer in a solvent. The solvent used in forming the adhesive layer can be used as the solvent.

[0049] (2) Through holes The resin film has through holes that penetrate in the thickness direction. The resin film has through holes, which allows water permeability, i.e., water permeability. Furthermore, since the resin film has through holes, the resin film is non-breathable in the planar direction but breathable in the thickness direction. Furthermore, when the adhesive layer is an energy ray-curable adhesive layer, the resin film has through holes, which allows energy ray permeability.

[0050] In the resin film, the planar shape of the through hole is not particularly limited, and examples thereof include a circle, an ellipse, a triangle, a square, a rectangle, and a hexagon. Among these, the planar shape of the through hole is preferably a rounded shape. If the shape has corners, the resin film is more likely to break from the corners. Therefore, a rounded shape can prevent the resin film from breaking. Specifically, the planar shape of the through hole is preferably a circle, an ellipse, or a polygon with rounded corners, and more preferably a circle or an ellipse.

[0051] The size of the through holes is preferably smaller than the chip size, for example, on the order of millimeters or less. The size of the through holes is, for example, 3 mm or less, or may be 1 mm or less, 500 μm or less, 200 μm or less, or 100 μm or less. On the other hand, the size of the through holes is preferably, for example, 10 μm or more. That is, the size of the through holes is, for example, 10 μm or more to 3 mm or less, 10 μm or more to 1 mm or less, 10 μm or more to 500 μm or less, 10 μm or more to 200 μm or less, or 10 μm or more to 100 μm or less. If the size of the through holes is too small, water permeability may be impaired. On the other hand, if the size of the through holes is too large, adhesion to the adhesive layer may be reduced.

[0052] The size of the through hole is the arithmetic average of 10 randomly selected holes. The size of the through hole is defined according to the shape of the through hole in plan view. For example, the size of the through hole refers to the diameter in the case of a circle, the major axis in the case of an ellipse, the diagonal length in the case of a square or rectangle, the maximum height in the case of a triangle, and the maximum diagonal length in the case of a hexagon.

[0053] The through holes may be arranged regularly or irregularly. When the through holes are arranged regularly, the arrangement of the through holes is not particularly limited, and examples thereof include a lattice arrangement and a staggered arrangement.

[0054] The aperture ratio A of the resin film is, for example, 30% or more, or may be 40% or more, or 50% or more. On the other hand, the aperture ratio A of the resin film is, for example, 80% or less, or may be 70% or less, or may be 60% or less. That is, the aperture ratio A of the resin film is, for example, 30% or more and 80% or less, or may be 40% or more and 70% or less, or may be 50% or more and 60% or less. If the aperture ratio is too small, water permeability may be impaired. On the other hand, if the aperture ratio is too large, the elongation at break of the adhesive tape for electronic component processing may be small. Furthermore, if the aperture ratio is too large, adhesion to the adhesive layer may be reduced. The method for determining the aperture ratio A of the resin film is as described above.

[0055] The method for forming through holes in a resin film is not particularly limited, and examples thereof include punching, laser processing, etc. Another method for forming a resin film having through holes is mold printing using gravure printing. In this case, a resin film having through holes is formed on a separator by mold printing using gravure printing, and the separator is peeled off to obtain a resin film having through holes.

[0056] (c) Resin film material The resin film material is not particularly limited as long as it satisfies the elongation at break of the adhesive tape for electronic component processing described below, but preferably satisfies the above-mentioned characteristics. Examples of resin film materials include olefin-based resins, vinyl chloride resins, polyester resins, urethane resins, polystyrene resins, polycarbonate resins, fluororesins, thermoplastic elastomers, and rubber-based materials. Examples of olefin-based resins include low-density polyethylene, high-density polyethylene, polypropylene, polybutene, polymethylpentene, polybutadiene, ethylene-vinyl acetate copolymers, ionomer resins, ethylene (meth)acrylic acid copolymers, and ethylene (meth)acrylic acid ester copolymers. Examples of vinyl chloride resins include polyvinyl chloride and vinyl chloride copolymers. Examples of polyester resins include polyethylene terephthalate and polybutylene terephthalate. Examples of thermoplastic elastomers include olefin-based elastomers, vinyl chloride-based elastomers, polyester-based elastomers, styrene-based elastomers, urethane-based elastomers, acrylic elastomers, and amide-based elastomers. Examples of rubber-based materials include isoprene rubber, butadiene rubber, styrene butadiene rubber, chloroprene rubber, acrylonitrile butadiene rubber, butyl rubber, halogenated butyl rubber, acrylic rubber, urethane rubber, polysulfide rubber, etc. These may be used alone or in combination of two or more.

[0057] The resin film may contain additives as needed, such as plasticizers, fillers, antioxidants, light stabilizers, antistatic agents, lubricants, dispersants, flame retardants, and colorants.

[0058] The resin film may be, for example, a single layer or a multilayer.

[0059] The surface of the resin film facing the adhesive layer may be subjected to a surface treatment to improve adhesion to the adhesive layer. The surface treatment is not particularly limited, and examples thereof include corona treatment, plasma treatment, ozone treatment, flame treatment, primer treatment, vapor deposition treatment, and alkali treatment.

[0060] The resin film may be a stretched film or a non-stretched film. Of these, the resin film is preferably a non-stretched film, which can improve the expandability.

[0061] (d) Resin film thickness The thickness of the resin film is not particularly limited as long as it satisfies the elongation at break of the adhesive tape for electronic component processing described below. The thickness of the resin film is preferably 100 μm or more, and may be 150 μm or more. By having the thickness of the resin film within the above range, the elongation at break of the adhesive tape for electronic component processing described below can be easily adjusted to fall within a predetermined range. On the other hand, the thickness of the resin film is, for example, 1000 μm or less, may be 500 μm or less, or may be 300 μm or less. If the thickness of the resin film is within the above range, the expandability of the resin film is good. Specifically, the thickness of the resin film is 100 μm or more and 1000 μm or less, may be 100 μm or more and 500 μm or less, may be 150 μm or more and 500 μm or less, or may be 150 μm or more and 300 μm or less.

[0062] The thickness of the resin film is measured using a thickness gauge such as a dial thickness gauge or a digital thickness gauge, and the arithmetic mean value of the thicknesses at 10 randomly selected locations is used. When measuring the thickness of the resin film, the adhesive layer is removed from the adhesive tape for electronic component processing, and the resin film is taken out. One method for removing the adhesive layer is to dissolve the adhesive layer in a solvent. The method for removing the adhesive layer is as described above.

[0063] 2. Adhesive layer The adhesive layer in the present disclosure is disposed on the first surface of the resin film and has a non-porous structure.

[0064] (1) Shape of adhesive layer In this specification, "the adhesive layer has a non-porous structure" means that the adhesive layer does not have through-holes at least in the thickness direction. As described above, when the workpiece substrate fixed to the adhesive tape for electronic component processing is fixed to the suction table during dicing, the through-holes in the resin film are covered with the adhesive layer, thereby preventing air leakage from areas of the adhesive tape where the workpiece substrate is not attached, and air leakage through the through-holes in the resin film from the cut portion of the workpiece substrate. Therefore, the adhesive layer may have a small number of holes as long as the above effect is not impaired.

[0065] (2) Shape of adhesive layer The adhesive layer in the present disclosure is not particularly limited as long as it can sufficiently fix the substrate and chip to the adhesive tape for electronic component processing in the dicing step, and can easily peel the chip from the adhesive tape for electronic component processing in the peeling step. Examples of adhesive layers include an energy ray-curable adhesive layer having energy ray curability and a weak adhesive layer exhibiting weak adhesiveness. Of these, an energy ray-curable adhesive layer is preferred. An energy ray-curable adhesive layer can increase the initial adhesive strength. Each adhesive layer will be described below.

[0066] (a) Energy ray curable adhesive layer The energy ray-curable adhesive layer is an adhesive layer whose adhesive strength decreases when irradiated with energy rays. In the energy ray-curable adhesive layer, the initial adhesive strength allows the substrate and chip to be sufficiently fixed to the adhesive tape for electronic component processing during the dicing process. Furthermore, during the peeling process, the adhesive strength decreases and the peelability improves when irradiated with energy rays, allowing the chip to be easily peeled from the adhesive tape for electronic component processing.

[0067] Examples of energy rays include light rays such as far ultraviolet rays, ultraviolet rays, near ultraviolet rays, visible light rays, and infrared rays, electromagnetic waves such as X-rays and gamma rays, as well as electron beams, proton beams, and neutron beams. Among these, from the viewpoint of versatility, ultraviolet rays and electron beams are preferred, and ultraviolet rays are more preferred.

[0068] The energy ray-curable adhesive layer is not particularly limited as long as it satisfies the desired adhesive properties, and can contain, for example, at least a resin (main adhesive agent) and an energy ray-curable compound. When the adhesive layer contains the energy ray-curable compound, the adhesive strength can be reduced by curing the energy ray-curable compound by irradiation with energy rays, and at the same time, the cohesive force is increased, making it easier to peel.

[0069] (i) Resin (main adhesive) Examples of resins (adhesive bases) include resins generally used as bases for adhesives, such as acrylic resins, polyester resins, polyimide resins, and silicone resins. Among these, acrylic resins are preferred. By using acrylic resins, adhesive residue on the adherend can be reduced.

[0070] Therefore, the adhesive layer preferably contains at least an acrylic resin, an energy ray-curable compound, and a crosslinking agent. In the adhesive layer, the acrylic resin is usually present as a crosslinked body formed by crosslinking between acrylic resin molecules with the crosslinking agent, but the acrylic resin may also be present as a simple substance together with the crosslinked body.

[0071] (acrylic resin) The acrylic resin is not particularly limited, and examples thereof include (meth)acrylic acid ester polymers obtained by homopolymerizing (meth)acrylic acid esters, and (meth)acrylic acid ester copolymers obtained by copolymerizing (meth)acrylic acid esters with other monomers and (meth)acrylic acid esters as the main component. Among these, (meth)acrylic acid ester copolymers are preferred. Specific examples of (meth)acrylic acid esters and other monomers include those disclosed in JP 2012-31316 A. The other monomers can be used alone or in combination of two or more. Here, "main component" means that the copolymerization ratio is 51% by mass or more, preferably 65% by mass or more.

[0072] Among these, as the acrylic resin, a (meth)acrylic acid ester copolymer having a (meth)acrylic acid ester as the main component and obtained by copolymerizing a hydroxyl group-containing monomer copolymerizable with the (meth)acrylic acid ester, or a (meth)acrylic acid ester copolymer having a (meth)acrylic acid ester as the main component and obtained by copolymerizing a hydroxyl group-containing monomer and a carboxyl group-containing monomer copolymerizable with the (meth)acrylic acid ester can be suitably used.

[0073] In this specification, (meth)acrylic acid refers to at least one of acrylic acid and methacrylic acid.

[0074] The copolymerizable hydroxyl group-containing monomer and carboxyl group-containing monomer are not particularly limited, and for example, the hydroxyl group-containing monomer and carboxyl group-containing monomer disclosed in JP-A-2012-31316 can be used.

[0075] The weight-average molecular weight of the acrylic resin is, for example, preferably from 200,000 to 1,000,000, and more preferably from 200,000 to 800,000. By setting the weight-average molecular weight of the acrylic resin within the above range, sufficient initial adhesive strength can be exhibited.

[0076] Here, in this specification, the weight-average molecular weight is a polystyrene-equivalent value measured by gel permeation chromatography (GPC). The weight-average molecular weight is measured, for example, using a measuring device HLC-8220GPC manufactured by Tosoh Corporation, a column TSKGEL-SUPERMULTIPORE-HZ-M manufactured by Tosoh Corporation, THF as a solvent, and standard polystyrenes with molecular weights of 1050, 5970, 18100, 37900, 96400, and 706000 as standards.

[0077] Furthermore, when the acrylic resin is a (meth)acrylic acid ester copolymer of a hydroxyl group-containing monomer copolymerizable with a (meth)acrylic acid ester and a carboxyl group-containing monomer, the mass ratio of the hydroxyl group-containing monomer to the carboxyl group-containing monomer is, for example, preferably 51:49 to 100:0, and more preferably 75:25 to 100:0. When the mass ratio of the monomers is within the above range, effective reduction in adhesive strength due to energy ray irradiation can be expected, and the occurrence of adhesive residue can be suppressed.

[0078] The acrylic resin may be energy ray-curable, for example, may have an energy ray-curable functional group in a side chain. The energy ray-curable functional group preferably has, for example, an ethylenically unsaturated bond, and specific examples thereof include a (meth)acryloyl group, a vinyl group, and an allyl group.

[0079] (ii) Energy ray curable compound The energy ray-curable compound is not particularly limited as long as it is polymerizable upon irradiation with energy rays, and examples thereof include compounds having an energy ray-curable functional group.

[0080] Examples of energy ray-curable compounds include energy ray-curable monomers, energy ray-curable oligomers, and energy ray-curable polymers. The energy ray-curable polymers are polymers different from the resins (adhesive bases) described above. Among them, energy ray-curable oligomers are preferred from the viewpoint of the balance of adhesive strength before and after energy ray irradiation. Furthermore, energy ray-curable monomers, energy ray-curable oligomers, and energy ray-curable polymers may be used in combination. For example, when an energy ray-curable monomer is used in addition to an energy ray-curable oligomer, the adhesive layer is cured by three-dimensional crosslinking upon irradiation with energy rays, thereby reducing adhesive strength and increasing cohesive strength to prevent transfer to the chip side.

[0081] Examples of the energy ray-curable compound include radically polymerizable compounds, cationically polymerizable compounds, and anionically polymerizable compounds. Among these, radically polymerizable compounds are preferred. They have a high curing rate, can be selected from a wide variety of compounds, and can easily control physical properties such as adhesive strength before and after energy ray irradiation.

[0082] In addition, the adhesive strength after the energy ray irradiation can be controlled by adjusting the number of energy ray-curable functional groups in the energy ray-curable compound. As described above, for example, as the number of energy ray-curable functional groups increases, the crosslink density of the adhesive layer after the energy ray irradiation increases, and the adhesive strength after the energy ray irradiation tends to decrease.

[0083] In the energy ray-curable compound, the number of energy ray-curable functional groups per molecule is preferably 2 or more, more preferably 3 or more, and even more preferably 4 or more. If the number of energy ray-curable functional groups is within the above range, the crosslinking density of the adhesive layer after energy ray irradiation is sufficient, thereby achieving the desired peelability. In addition, the occurrence of adhesive residue due to a decrease in cohesive force can be suppressed. In addition, the upper limit of the number of energy ray-curable functional groups is not particularly limited.

[0084] The energy ray-curable compound is preferably a radical polymerizable oligomer, more preferably a radical polymerizable polyfunctional oligomer, such as those disclosed in JP 2012-31316 A.

[0085] In addition, as the energy ray-curable compound, a radical polymerizable oligomer or a radical polymerizable monomer may be used, and in particular, a radical polymerizable polyfunctional oligomer or a radical polymerizable polyfunctional monomer may be used. Examples of the radical polymerizable monomer include those disclosed in JP 2010-173091 A.

[0086] Examples of the energy ray curable compound include (meth)acrylate monomers, (meth)acrylate oligomers, (meth)acrylate polymers, etc. Examples of the energy ray curable compound that can be used include urethane (meth)acrylate, polyester (meth)acrylate, and epoxy (meth)acrylate.

[0087] Commercially available energy ray-curable compounds may also be used. For example, Mitsubishi Chemical Corporation's urethane acrylate "Shikou UV7620EA (molecular weight: 4100)" and Negami Chemical Industrial Co., Ltd.'s urethane acrylates "Art Resin UN-905 (molecular weight: 50,000 to 210,000)," "Art Resin UN-905DU1 (molecular weight: 26,000)," "Art Resin UN-951SC (molecular weight: 12,500)," "Art Resin UN-952 (molecular weight: 6,500 to 9,500)," "Art Resin UN-953 (molecular weight: 14,000 to 40,000)," "Art Resin UN-954 (molecular weight: 4,200)," and "Art Resin H-219 (molecular weight: 14,000 to 40,000)" are available. Examples of suitable polymers include "Art Resin H-315M (molecular weight: 6600)" and "Art Resin H-417M (molecular weight: 4000)" manufactured by Taisei Fine Chemical Co., Ltd., "8BR-600 (molecular weight: 100000)" acrylic urethane polymer manufactured by Taisei Fine Chemical Co., Ltd., "Unidic V-6850" polymer acrylate manufactured by DIC Corporation, "SMP-250AP (molecular weight: 20000-30000)" and "SMP-360A (molecular weight: 20000-30000)" acrylic polymer manufactured by Kyoeisha Chemical Co., Ltd., and "HA7975" acrylic resin acrylate manufactured by Showa Denko Materials Co., Ltd.

[0088] The energy ray-curable compounds may be used alone or in combination of two or more.

[0089] The weight-average molecular weight of the energy ray-curable compound is not particularly limited, but is preferably 30,000 or less, more preferably 10,000 or less, and even more preferably 8,000 or less. If the weight-average molecular weight of the energy ray-curable compound is within the above range, it exhibits sufficient compatibility with the acrylic resin (main adhesive agent), and the adhesive layer exhibits the desired adhesive strength before energy ray irradiation, and after energy ray irradiation, the occurrence of adhesive residue is suppressed and it can be easily peeled off. On the other hand, the weight-average molecular weight of the energy ray-curable resin composition is, for example, 500 or more.

[0090] Furthermore, the adhesive strength after irradiation with energy rays can be controlled by adjusting the content of the energy ray-curable compound. If the content of the energy ray-curable compound is high, the adhesive strength after irradiation with energy rays tends to be low.

[0091] The content of the energy ray-curable compound is, for example, preferably 5 to 150 parts by mass, more preferably 20 to 100 parts by mass, and even more preferably 50 to 80 parts by mass, per 100 parts by mass of the resin (main adhesive agent). If the content of the energy ray-curable compound is within the above range, the crosslink density of the adhesive layer after energy ray irradiation is sufficient, thereby achieving the desired peelability. In addition, the occurrence of adhesive residue due to a decrease in cohesive force can be suppressed.

[0092] (iii) Polymerization initiator The adhesive layer may contain a polymerization initiator in addition to the resin (main adhesive agent) and the energy ray-curable compound.

[0093] As the polymerization initiator, a general photopolymerization initiator can be used. Specific examples include acetophenones, benzophenones, α-hydroxyketones, benzyl methyl ketals, α-aminoketones, and bisacylphosphine oxides. When a urethane acrylate is used as the energy ray-curable compound, the polymerization initiator is preferably a bisacylphosphine-based polymerization initiator. Because this polymerization initiator has heat resistance, it can reliably cure the energy ray-curable compound even when the adhesive layer is irradiated with energy rays through a resin film.

[0094] The polymerization initiator preferably has absorption at wavelengths of 230 nm or more, and preferably at wavelengths of 300 nm to 400 nm. Such polymerization initiators can absorb energy rays with a wide wavelength range of 300 nm or more and efficiently generate active species that induce polymerization reactions of energy ray-curable compounds. Therefore, even with a small amount of energy ray irradiation, the energy ray-curable compound can be efficiently cured and easily peeled off. Furthermore, many resin films absorb energy rays with wavelengths up to about 300 nm but transmit energy rays with wavelengths of about 300 nm or more. Furthermore, in recent years, LED lamps with wavelengths of 300 nm or more are often used in energy ray irradiation devices. Therefore, by using a polymerization initiator with absorption at wavelengths of 230 nm or more, the energy ray-curable compound can be cured using energy rays that have transmitted through the resin film.

[0095] The content of the polymerization initiator is, for example, preferably 0.01 to 10 parts by mass, more preferably 0.5 to 6 parts by mass, per 100 parts by mass of the total of the resin (main adhesive agent) and the energy ray-curable compound. If the content of the polymerization initiator is below the above range, the polymerization reaction of the energy ray-curable compound may not occur sufficiently, resulting in excessively high adhesive strength of the adhesive layer after energy ray irradiation and inability to achieve peelability. On the other hand, if the content of the polymerization initiator exceeds the above range, the energy ray may only reach the vicinity of the energy ray-irradiated surface, resulting in insufficient curing of the adhesive layer. Furthermore, the cohesive force may decrease, which may cause adhesive residue.

[0096] (iv) Crosslinking agent The adhesive layer may contain a crosslinking agent in addition to the resin (main adhesive agent) and the energy ray-curable compound.

[0097] The crosslinking agent is not particularly limited as long as it crosslinks at least between resins (main adhesive agents), and is appropriately selected depending on the type of resin (main adhesive agent), etc. Examples include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, and metal chelate-based crosslinking agents. Specific examples of isocyanate-based crosslinking agents and epoxy-based crosslinking agents include those disclosed in JP 2012-31316 A. The crosslinking agents can be used alone or in combination of two or more.

[0098] The content of the crosslinking agent is appropriately set depending on the type of crosslinking agent, and is, for example, preferably 0.01 to 15 parts by mass, more preferably 0.01 to 10 parts by mass, per 100 parts by mass of the resin (main adhesive). If the content of the crosslinking agent is below the above range, the adhesion may be poor, or the adhesive layer may undergo cohesive failure when peeling the chip, resulting in adhesive residue. On the other hand, if the content of the crosslinking agent exceeds the above range, the crosslinking agent may remain in the adhesive layer as unreacted monomer after energy ray irradiation, which may reduce cohesive strength and cause adhesive residue.

[0099] (v) Additives The adhesive layer may contain various additives as needed, such as a tackifier, an antistatic agent, a plasticizer, a silane coupling agent, a metal chelating agent, a surfactant, an antioxidant, an ultraviolet absorber, a colorant, a preservative, an antifoaming agent, and a wettability adjuster.

[0100] (vi) Other The energy ray-curable adhesive layer can be formed, for example, by applying an adhesive composition onto a separator. After the adhesive layer is formed, a resin film is placed on the adhesive layer to obtain an adhesive tape for processing electronic components, which has the resin film, adhesive layer, and separator in this order.

[0101] (b) Slightly adhesive adhesive layer The weak adhesive layer is an adhesive layer that exhibits weak adhesion. Although the weak adhesive layer has low initial adhesive strength, it can sufficiently fix the substrate and chip to the adhesive tape for electronic component processing during the dicing process. Furthermore, because the initial adhesive strength is low, it has excellent removability, and during the peeling process, the chip can be easily peeled from the adhesive tape for electronic component processing.

[0102] Here, the term "weak adhesive layer exhibits weak adhesion" means that the adhesive layer exhibits sufficient adhesive strength to fix the substrate and chip to the adhesive tape for electronic component processing sufficiently during the dicing process, and to easily peel the chip from the adhesive tape for electronic component processing during the peeling process.

[0103] The weak adhesive layer is not particularly limited as long as it has the desired adhesive properties. In particular, the weak adhesive layer preferably contains at least an acrylic resin, and more preferably contains an acrylic resin and a crosslinking agent.

[0104] Here, when the low-tack adhesive layer contains an acrylic resin, it means that the acrylic resin may exist in the low-tack adhesive layer as a single entity without forming crosslinks, or as a crosslinked entity formed by crosslinking between acrylic resins or between acrylic resins and other resins, or both the single entity and the crosslinked entity may be present.

[0105] Here, the adhesive layer containing an acrylic resin means that the acrylic resin may exist in the adhesive layer as a single entity without forming crosslinks, or as a crosslinked entity formed by crosslinking between acrylic resins or between an acrylic resin and another resin, or both the single entity and the crosslinked entity may be present.

[0106] (i) Acrylic resin The acrylic resin is not particularly limited, and examples thereof include a (meth)acrylic acid ester polymer obtained by homopolymerizing a (meth)acrylic acid ester, and a (meth)acrylic acid ester copolymer obtained by copolymerizing a (meth)acrylic acid ester as a main component with a (meth)acrylic acid ester and other monomers. Among these, a (meth)acrylic acid ester copolymer is preferred.

[0107] Here, in a (meth)acrylic acid ester copolymer, "having a (meth)acrylic acid ester as the main component" means that the proportion of the (meth)acrylic acid ester relative to other monomers in the copolymer is greater than 30% by mass, and specifically means that the copolymerization proportion is 51% by mass or more.

[0108] In this specification, (meth)acrylic acid refers to at least one of acrylic acid and methacrylic acid.

[0109] Examples of (meth)acrylic acid esters that can be used include (meth)acrylic acid alkyl esters, such as linear or branched alkyl esters having from 1 to 30 carbon atoms, and (meth)acrylic acid cycloalkyl esters. Specific examples of (meth)acrylic acid alkyl esters include those disclosed in JP 2014-101457 A. One or more types of (meth)acrylic acid esters may be used. Of these, (meth)acrylic acid esters having from 1 to 18 carbon atoms, and particularly from 1 to 8 carbon atoms, are preferred. The glass transition temperature of the acrylic resin is likely to fall within the range described below, which can improve the adhesiveness of the adhesive layer.

[0110] The acrylic resin may be a copolymer of a (meth)acrylic acid ester and a monomer or oligomer. In addition to the (meth)acrylic acid ester, other monomers or oligomers may be included as copolymerization components, if necessary, to improve properties such as cohesive strength and heat resistance. Examples of the copolymerization component include functional group-containing (meth)acrylates copolymerizable with the (meth)acrylic acid ester. Specific examples include carboxyl group-containing monomers, acid anhydride group-containing monomers, hydroxyl group-containing monomers, sulfonic acid group-containing monomers, phosphate group-containing monomers, epoxy group-containing monomers, vinyl esters, vinyl ethers, and aromatic vinyl compounds. Nitrogen-containing monomers such as cyano group-containing monomers, amide group-containing monomers, amino group-containing monomers, and isocyanate group-containing monomers may also be used as copolymerization components. The copolymerization component may be included in an acrylic acid ester polymer as a copolymerization component.

[0111] The weight-average molecular weight of the acrylic resin is, for example, preferably 100,000 or more and 2,000,000 or less, more preferably 200,000 or more and 1,000,000 or less, and even more preferably 400,000 or more and 800,000 or less. If the weight-average molecular weight is smaller than the above range, adhesive residue may occur in the adhesive layer. On the other hand, if the weight-average molecular weight is larger than the above range, the adhesive strength may increase and the peelability may decrease.

[0112] The glass transition temperature of the acrylic resin is, for example, preferably −100° C. or higher and 0° C. or lower, and more preferably −80° C. or higher and −20° C. or lower. By using an acrylic resin having a glass transition temperature within the above range as the main component, desired adhesive properties can be easily obtained.

[0113] The glass transition temperature of an acrylic resin can be adjusted appropriately by changing the type of monomer unit used, the ratio of the monomer units to be combined, etc. Even in the case of an acrylic resin in the form of a polymer (homopolymer) obtained by homopolymerizing a monomer, the glass transition temperature may be within the above range. However, the use of a monomer unit whose homopolymer glass transition temperature is not within the above range is not restricted. It is sufficient that the glass transition temperature of a copolymer obtained by copolymerizing a combination of various monomer units is within the above range.

[0114] In this specification, the glass transition temperature refers to a value measured by a method (DMA method) based on the peak-top value of the loss tangent (tan δ). The loss tangent is determined by the value of loss modulus / storage modulus. These moduli are measured using a dynamic viscoelasticity measuring device to measure the stress when a force is applied to a polymer or copolymer at a certain frequency.

[0115] The acrylic resin can be obtained by polymerizing a monomer such as the above-mentioned (meth)acrylic acid ester, monomer, or oligomer by a conventional method such as solution polymerization, bulk polymerization, emulsion polymerization, or suspension polymerization.

[0116] (ii) Crosslinking Agent The crosslinking agent may be any common crosslinking agent capable of crosslinking the acrylic resin, such as an epoxy crosslinking agent, an isocyanate crosslinking agent, a metal chelate crosslinking agent, or a carbodiimide crosslinking agent.

[0117] The content of the crosslinking agent is, for example, 0.1 to 20 parts by mass, preferably 0.3 to 10 parts by mass, relative to 100 parts by mass of the acrylic resin. When the content of the crosslinking agent is within the above range, desired adhesive properties can be easily obtained.

[0118] (iii) Other ingredients The adhesive layer may contain any additives, such as a lubricant, a plasticizer, a bulking agent, an antistatic agent, an antiblocking agent, a light stabilizer, a colorant, etc., as needed.

[0119] (iv) Other The method for forming the weakly adhesive layer is the same as the method for forming the energy ray curable adhesive layer.

[0120] (3) Thickness of adhesive layer The thickness of the adhesive layer may be any thickness that provides the desired adhesive strength, for example, 10 μm or more, 25 μm or more, or even 50 μm or more. When the thickness of the adhesive layer is within the above range, the adhesion between the adhesive sheet for electronic components and the substrate or chip to be processed is improved, and chip flying during water jet laser processing can be suppressed. On the other hand, the thickness of the adhesive layer is, for example, 200 μm or less. If the adhesive layer is too thick, water permeability may be reduced.

[0121] 3. Other configurations The adhesive tape for processing electronic components according to the present disclosure may have other components as needed in addition to the resin film and adhesive layer described above. The adhesive tape for processing electronic components according to the present disclosure may have a separator on the surface of the adhesive layer opposite to the resin film.

[0122] 4. Characteristics of adhesive tape for electronic component processing (1) Elongation at break In the present disclosure, the elongation at break of the adhesive tape for electronic component processing is 100% or more, or may be 500% or more, or even 1000% or more. When the elongation at break is within the above range, breakage of the adhesive tape for electronic component processing during expansion can be suppressed. Furthermore, when the elongation at break is within the above range, it can be said that the adhesive tape for electronic component processing has good expandability. Meanwhile, there is no particular upper limit for the elongation at break of the adhesive tape for electronic component processing.

[0123] The elongation at break of adhesive tapes for electronic component processing is measured in accordance with JIS K7127:1999. Specific measurement conditions are shown below. The tensile tester used is, for example, the "Tensilon RTF1150" manufactured by A&D Co., Ltd.

[0124] <Measurement conditions> Test piece: rectangular test piece (width 10 mm, length 60 mm) ·Distance between gauge lines: 25mm Initial distance between chucks: 25mm Pulling speed: 200mm / min ·Temperature: 23±2℃ ·Humidity: 50±10%RH

[0125] Methods for controlling the elongation at break of the adhesive tape for processing electronic components include, for example, adjusting the material of the resin film, adjusting the tensile modulus of elasticity of the resin film, adjusting the opening ratio of the resin film, and adjusting the manufacturing method of the resin film.

[0126] When adjusting the material of the resin film, for example, if an olefin resin, vinyl chloride resin, or thermoplastic elastomer is used, the elongation at break of the adhesive tape for processing electronic components tends to be large.

[0127] If the tensile modulus of the resin film is small, the resin film tends to be soft, and therefore the elongation at break of the adhesive tape for processing electronic components tends to be large, whereas if the tensile modulus of the resin film is large, the resin film tends to be hard, and therefore the elongation at break of the adhesive tape for processing electronic components tends to be small.

[0128] When the resin film material is the same, if the resin film has a small opening ratio, the adhesive tape for electronic component processing tends to have a large elongation at break, while if the resin film has a large tensile modulus, the adhesive tape for electronic component processing tends to have a small elongation at break.

[0129] When adjusting the manufacturing method of the resin film, if the resin film is a non-stretched film, the elongation at break of the adhesive tape for processing electronic components tends to be large, whereas if the resin film is a stretched film, the elongation at break of the adhesive tape for processing electronic components tends to be small.

[0130] (2) Adhesive strength (a) Energy ray curable adhesive layer When the adhesive layer is an energy ray-curable adhesive layer, the peel strength between the resin film and the adhesive layer after irradiation with energy rays is preferably equal to or greater than the adhesive strength to the glass substrate after irradiation with energy rays, thereby preventing adhesive residue on the adherend.

[0131] When the adhesive layer is an energy ray-curable adhesive layer, the adhesive strength of the adhesive tape for electronic component processing to a glass plate before energy ray irradiation may be, for example, 0.5 N / 25 mm or more and 40 N / 25 mm or less. Furthermore, the adhesive strength to a glass plate after energy ray irradiation is preferably, for example, 2.0 N / 25 mm or less. The lower limit of the adhesive strength to a glass plate after energy ray irradiation is not particularly limited, and is, for example, 0.01 N / 25 mm or more.

[0132] The adhesive strength to the glass plate is measured according to Method 1 of JIS Z0237:2022 (Test Methods for Adhesive Tapes and Sheets) (a test method in which the tape or sheet is peeled off at an angle of 180° from the stainless steel test plate at a temperature of 23°C and humidity of 50%), by peeling the test piece lengthwise at a width of 25 mm, a peel angle of 180°, and a peel speed of 300 mm / min. The glass plate used is float glass (150 mm x 70 mm, 2 mm thick) manufactured by Osaka Glass Industry Co., Ltd.

[0133] When the adhesive layer is an energy ray-curable adhesive layer, the peel strength between the resin film and the adhesive layer in the adhesive tape for electronic component processing after energy ray irradiation may be, for example, equal to or greater than the adhesive strength to a glass plate after energy ray irradiation, and may be at least twice the adhesive strength to a glass plate after energy ray irradiation. When the peel strength is within the above range, the adhesion between the resin film and the adhesive layer after energy ray irradiation is high, thereby suppressing adhesive residue on the adherend. On the other hand, the upper limit of the peel strength is not particularly limited. For example, when the peel strength between the resin film and the adhesive layer after energy ray irradiation is very high, the peel strength between the resin film and the adhesive layer may be equal to or greater than the peel strength between the adhesive tape for electronic component processing and the adherend in the method for measuring the peel strength between the resin film and the adhesive layer after energy ray irradiation described below, and peeling may not occur between the resin film and the adhesive layer.

[0134] Here, the peel strength between the resin film and the adhesive layer after energy ray irradiation is measured by a T-peel test. Specifically, first, an adhesive tape for electronic component processing is prepared, which has a resin film, an adhesive layer, and a separator in this order. At this time, if a separator is not arranged on the adhesive layer side opposite the resin film in the adhesive tape for electronic component processing, a separator is arranged on the adhesive layer side opposite the resin film. Next, the adhesive layer of the adhesive tape for electronic component processing is irradiated with energy rays to harden it. For example, the energy rays are irradiated from the resin film side of the adhesive tape for electronic component processing. Next, the separator is peeled from the adhesive tape for electronic component processing to expose the adhesive layer. Next, an adherend (polyester adhesive tape No. 31B manufactured by Nitto Denko Corporation) is bonded to the adhesive layer side of the adhesive tape for electronic component processing (one reciprocating motion) using a 2 kg roller, and cut to a width of 25 mm. After that, the adhesive tape is aged for 6 hours to prepare a test specimen. Next, the resin film and adhesive layer of the test specimen are forcibly peeled in the longitudinal direction of the test specimen. The edges of the peeled portion between the resin film and adhesive layer of the test specimen are clamped with the gripping tools of a tensile tester, and a T-shaped peel is performed at a peel speed of 300 mm / min and a peel distance of 50 mm to measure the peel strength between the resin film and adhesive layer after energy beam irradiation. The measurement environment is a temperature of 23°C and a humidity of 50% RH. An example of a tensile tester used is a Tensilon RTF1150 manufactured by A&D Corporation.

[0135] Examples of means for controlling the peel force between the resin film and the adhesive layer after irradiation with energy rays include adjusting the opening ratio of the resin film, applying a surface treatment to the resin film, adjusting the thickness of the adhesive layer, adjusting the components and composition contained in the adhesive layer, and adjusting the aging temperature when forming the adhesive layer or when laminating the resin film and adhesive layer.

[0136] In a method for adjusting the opening rate of a resin film, for example, when the thickness of the adhesive layer is constant, a smaller opening rate of the resin film increases the contact area between the resin film and the adhesive layer, which improves the adhesion between the resin film and the adhesive layer and tends to increase the peel force.

[0137] In addition, in the method of subjecting a resin film to a surface treatment, for example, the peeling force can be increased by subjecting the resin film to a surface treatment.

[0138] In addition, in the method of adjusting the thickness of the adhesive layer, the thicker the adhesive layer, the better the adhesion between the resin film and the adhesive layer, and the peel force tends to be greater.

[0139] Specific examples of methods for adjusting the components and composition of the adhesive layer include adjusting the content, number of functional groups, and molecular weight of the energy ray-curable compound, and adding a tackifier. For example, when the content of the energy ray-curable compound is low, the peel force tends to be high, while when the content of the energy ray-curable compound is high, the peel force tends to be low. For example, when the number of energy ray-curable functional groups in the energy ray-curable compound is low, the peel force tends to be high, while when the number of energy ray-curable functional groups in the energy ray-curable compound is high, the peel force tends to be low. For example, when the molecular weight of the energy ray-curable compound is low, the peel force tends to be high, while when the molecular weight of the energy ray-curable compound is high, the peel force tends to be low. For example, adding a tackifier tends to increase the peel force.

[0140] In addition, in a method of adjusting the aging temperature when forming the adhesive layer or when laminating the resin film and adhesive layer, for example, if the aging temperature is high, the peel force tends to be large, while if the aging temperature is low, the peel force tends to be small.

[0141] (b) Slightly adhesive adhesive layer When the adhesive layer is a weak adhesive layer, the peel strength between the resin film and the adhesive layer is preferably equal to or greater than the adhesive strength to the glass substrate, thereby preventing adhesive residue on the adherend.

[0142] When the adhesive layer is a weak adhesive layer, the adhesive strength of the adhesive tape for electronic component processing to a glass plate is 6.0 N / 25 mm or less, or may be 3.0 N / 25 mm or less, or may be 0.5 N / 25 mm or less, while the adhesive strength to a glass plate is, for example, 0.05 N / 25 mm or more.

[0143] Here, the method for measuring the adhesive strength to the glass plate is the same as the method for measuring the adhesive strength to the glass plate in the case of the energy ray curable adhesive layer.

[0144] When the adhesive layer is a weak adhesive layer, the peel strength between the resin film and the adhesive layer in the adhesive tape for electronic component processing may be, for example, equal to or greater than the adhesive strength to a glass plate after the above-mentioned energy ray irradiation, and may be at least twice the adhesive strength to a glass plate after the above-mentioned energy ray irradiation. When the peel strength is within the above range, the adhesion between the resin film and the adhesive layer is high, thereby suppressing adhesive residue on the adherend. On the other hand, the upper limit of the peel strength is not particularly limited. For example, when the peel strength between the resin film and the adhesive layer after energy ray irradiation is very high, in the method for measuring the peel strength between the resin film and the adhesive layer after energy ray irradiation described below, the peel strength between the resin film and the adhesive layer may be equal to or greater than the peel strength between the adhesive tape for electronic component processing and the adherend, and the resin film and the adhesive layer may not peel.

[0145] The peel strength between the resin film and the adhesive layer is measured using a T-peel test. Specifically, an adherend (Nitto Denko Corporation's polyester adhesive tape No. 31B) is first bonded to the adhesive layer of an adhesive tape for electronic component processing (one round trip) using a 2 kg roller, and then cut to a width of 25 mm. This is then aged for 6 hours to prepare a test specimen. Next, the resin film and adhesive layer of the test specimen are forcibly peeled along the length of the specimen. The edges of the peeled portion between the resin film and adhesive layer of the test specimen are clamped with the grips of a tensile tester, and a T-peel test is performed at a peel speed of 300 mm / min and a peel distance of 50 mm to measure the peel strength between the resin film and adhesive layer after energy beam irradiation. The measurement environment is a temperature of 23°C and a humidity of 50% RH. A Tensilon RTF1150 manufactured by A&D Corporation, for example, is used as the tensile tester.

[0146] Examples of means for controlling the peel force between the resin film and the adhesive layer include adjusting the opening ratio of the resin film, applying a surface treatment to the resin film, adjusting the thickness of the adhesive layer, adjusting the components and composition contained in the adhesive layer, and adjusting the aging temperature when forming the adhesive layer or when laminating the resin film and adhesive layer.

[0147] The methods for adjusting the opening ratio of the resin film, the method for surface treating the resin film, the method for adjusting the thickness of the adhesive layer, and the method for adjusting the aging temperature during formation of the adhesive layer or during lamination of the resin film and adhesive layer are the same as those for the energy ray-curable adhesive layer described above.

[0148] Furthermore, a specific example of a method for adjusting the components and composition contained in the adhesive layer is to add a tackifier. For example, adding a tackifier tends to increase the peel strength.

[0149] 5.Applications The adhesive tape for electronic component processing according to the present disclosure can be used as a dicing tape. In particular, the adhesive tape for electronic component processing according to the present disclosure can be suitably used as a dicing tape when dicing a workpiece substrate by laser processing. In particular, the adhesive tape for electronic component processing according to the present disclosure can be suitably used as a dicing tape when dicing a workpiece substrate by water jet laser processing.

[0150] B. Manufacturing methods for electronic components The method for manufacturing electronic components in the present disclosure includes an application step of applying the above-mentioned adhesive tape for electronic component processing to a first surface of a substrate to be processed, a dicing step of dividing the substrate to be processed into a plurality of chips, an expanding step of stretching the adhesive tape for electronic component processing to increase the spacing between the chips, and a pick-up step of picking up the chips from the adhesive tape for electronic component processing.

[0151] 6(a) to 6(f) are process diagrams illustrating an example of a method for manufacturing an electronic component according to the present disclosure. First, as shown in FIG. 6(a), a bonding process is performed in which the adhesive layer surface of the adhesive tape 10 for electronic component processing is bonded to a ring frame 21, and then a substrate 11 to be processed is bonded to the adhesive layer surface of the adhesive tape 10 for electronic component processing. Next, as shown in FIG. 6(b), a dicing process is performed in which the substrate 11 to be processed is divided into chips 12. Next, as shown in FIG. 6(c), an expanding process is performed in which the adhesive tape 10 for electronic component processing is stretched to increase the spacing between the chips 12. Next, if the adhesive layer of the adhesive tape 10 for electronic component processing is an energy ray-curable adhesive layer, as shown in FIG. 6(d), an irradiation process is performed in which the adhesive layer of the adhesive tape 10 for electronic component processing is irradiated with energy rays 25 from the resin film side to harden and reduce the adhesive strength. Next, as shown in FIG. 6(e), a pick-up process is performed in which the chips 12 are peeled off from the adhesive tape 10 for electronic component processing and picked up. Next, as shown in FIG. 6(f), a mounting (die bonding) step is performed in which the picked-up chip 12 is bonded to a substrate 26.

[0152] In the present disclosure, the adhesive tape for electronic component processing described above is used, thereby suppressing misalignment during the dicing process. Furthermore, in the present disclosure, the adhesive tape for electronic component processing described above is used, thereby improving the expandability of the adhesive tape for electronic component processing. Therefore, breakage of the adhesive tape for electronic component processing during the dicing process and the expanding process can be suppressed.

[0153] A general method can be applied to each step in the method for manufacturing an electronic component according to the present disclosure.

[0154] In the dicing process, the substrate to be processed, which is fixed to the adhesive tape for electronic component processing, is fixed by suction to a suction table. A porous chuck or the like is used as the suction table. A glass suction table is preferably used as the suction table because it does not absorb laser light.

[0155] In particular, in the dicing step, it is preferable to divide the substrate into a plurality of chips by a laser guided by a water jet. General conditions can be adopted for the water jet laser processing.

[0156] When the adhesive layer is an energy ray-curable adhesive layer, a curing step is performed after the dicing step and before the pick-up step, in which the adhesive layer of the adhesive tape for processing electronic components is irradiated with energy rays to be cured. The curing step may be performed between the dicing step and the expanding step, or between the expanding step and the pick-up step.

[0157] The present disclosure is not limited to the above-described embodiments. The above-described embodiments are merely examples, and any configuration that is substantially identical to the technical idea described in the claims of the present disclosure and that provides similar effects is included within the technical scope of the present disclosure. [Example]

[0158] Hereinafter, the present disclosure will be further described with reference to examples and comparative examples.

[0159] [Example 1] A pressure-sensitive adhesive composition was prepared by diluting 100 parts by mass of the adhesive base (acrylic acid copolymer), 50 parts by mass of urethane acrylate (ultraviolet-curable compound, 9 functional groups, molecular weight 4100, active content 65%), 7.5 parts by mass of a photopolymerization initiator (IGM Resins BV "Omnirad 819"), and 3 parts by mass of a crosslinking agent (isocyanate-based curing agent (tolylene diisocyanate (TDI)-based adduct type (trimethylolpropane adduct)), solid content 75%) with a mixed solvent of toluene and methyl ethyl ketone (mass ratio 1:1) and thoroughly dispersing the mixture.

[0160] The resin film used was a 265 μm thick polyolefin film (manufactured by Meiwa Gravure Co., Ltd.) with through holes. The polyolefin film was formed by mold printing using gravure printing. In the polyolefin film, the through holes had a circular shape in plan view, a diameter of 1 mm, a pitch of 2 mm, a staggered arrangement, and an aperture ratio of 39%.

[0161] The adhesive composition was applied to a polyethylene terephthalate (PET) separator (Nippa Corporation, "PET50x1-M-J2", thickness 50 μm) so that the thickness after drying was 50 μm, and the adhesive layer was formed by drying in an oven at 110°C for 3 minutes. Next, the resin film was laminated onto the adhesive layer, and then aged at 40°C for 3 days. This produced an adhesive tape for processing electronic components, which had a resin film, adhesive layer, and separator in that order.

[0162] [Example 2] An adhesive tape for processing electronic components was produced in the same manner as in Example 1, except that a 150 μm thick polystyrene film (manufactured by Meiwa Gravure Co., Ltd.) with through holes was used as the resin film. The polystyrene film was formed by mold printing using gravure printing. In the polystyrene film, the through holes had a circular shape in plan view, a diameter of 1 mm, a pitch of 2 mm, a staggered arrangement, and an aperture ratio of 39%.

[0163] [Example 3] An adhesive tape for processing electronic components was produced in the same manner as in Example 1, except that a 220 μm thick polystyrene elastomer film (manufactured by Meiwa Gravure Co., Ltd.) with through holes was used as the resin film. The polystyrene elastomer film was formed by mold printing using gravure printing. In the polystyrene elastomer film, the through holes had a circular shape in plan view, a diameter of 1 mm, a pitch of 2 mm, a staggered arrangement, and an aperture ratio of 39%.

[0164] [Example 4] An adhesive tape for electronic component processing was produced in the same manner as in Example 1, except that the following polypropylene film was used as the resin film. Circular through-holes with a diameter of 1 mm were randomly formed in the 150 μm-thick polypropylene film using a hole punch. The opening ratio of the polypropylene film was 39%.

[0165] [Comparative Example 1] Except for using a 270 μm thick nylon mesh ("NB90" manufactured by NBC Meshtec Co., Ltd.) instead of the resin film, an adhesive tape for processing electronic components was produced in the same manner as in Example 1. The opening of the nylon mesh was approximately 0.1 mm.

[0166] [Comparative Example 1] An adhesive tape for processing electronic parts was produced in the same manner as in Example 1, except that a polypropylene film having no through holes and a thickness of 150 μm was used as the resin film.

[0167] [evaluation] (1) Elongation at break of adhesive tape for electronic component processing The adhesive tape for electronic component processing was cut into 10 mm x 60 mm pieces to obtain test pieces. A tensile test was performed using an A&D "Tensilon RTF1150" tensile tester under the following conditions in accordance with JIS K7127:1999 to determine the elongation at break.

[0168] <Measurement conditions> Test piece: rectangular test piece (width 10 mm, length 60 mm) ·Distance between gauge lines: 25mm Initial distance between chucks: 25mm Pulling speed: 200mm / min ·Temperature: 23±2℃ ·Humidity: 50±10%RH

[0169] (2) Vacuum suction The adhesive tape for electronic component processing was cut to a size of 210 mm x 210 mm to obtain a test piece. The adhesive tape for electronic component processing was placed on the 200 mm diameter ceramic porous chuck table of a Harmotec tape remover "HTR0608-1," and vacuum suction was initiated. The vacuum pump used for vacuum suction was the ULVAC vacuum pump "DA-20D." While the vacuum was being drawn, the differential pressure between the pressure inside the ceramic porous chuck table and atmospheric pressure was measured using a dial-type differential pressure gauge attached to the device. The vacuum suction was evaluated according to the following criteria. A: The differential pressure was -30kPa or less. B: The differential pressure was greater than -30 kPa.

[0170] (3) Positional deviation Adhesive tape for electronic component processing was applied to a ring frame for 6-inch wafers, and a 100 μm-thick 6-inch silicon wafer was adhered and fixed to the adhesive tape for electronic component processing. Using a water jet laser dicing device (SYNOVA's "Laser Microjet"), 30 cutting lines were cut vertically and horizontally at a cutting speed of 100 mm / s, a laser wavelength of 532 nm, a water jet diameter of 40 μm, and a water pressure of 250 bar. The wafer was then diced into 841 chips measuring 1.8 mm x 1.8 mm. The deviation of the actual cutting line positions from the center line of the dicing street (scribe line) as designed was then observed under a microscope. The deviation was evaluated according to the following criteria. A: The positional deviation was 10 μm or less. B: The positional deviation was more than 10 μm.

[0171] (4) Chip cracking The silicon wafer was diced in the same manner as in the evaluation of misalignment described above, and the presence or absence of chip cracks was checked.

[0172] [Table 1]

[0173] As in Examples 1 to 3, it was confirmed that misalignment was suppressed by the resin film being non-breathable in the plane direction, having through holes, and the adhesive layer having a non-porous structure. In Example 4, only the elongation at break and vacuum suction were evaluated. It is believed that Example 4 also achieves the same effects as Examples 1 to 3. On the other hand, in Comparative Example 1, the nylon mesh was breathable in the plane direction, so the adhesive tape for electronic component processing was not vacuum-sucked to the porous chuck table. In Comparative Example 2, water was not able to pass through the polypropylene film, so the rebound of the water jet caused chip cracking.

[0174] The present disclosure provides the following inventions. [1] A resin film having a first surface and a second surface opposite to the first surface, having non-air permeability in the surface direction, and having through holes penetrating in the thickness direction; an adhesive layer having a non-porous structure, the adhesive layer being disposed on the first surface of the resin film; An adhesive tape for processing electronic components, comprising: The adhesive tape for processing electronic components has an elongation at break of 100% or more. [2] The adhesive tape for processing electronic parts according to [1], wherein the resin film is non-absorbent to laser light. [3] The adhesive tape for processing electronic parts according to [1] or [2], wherein the resin film has a thickness of 100 μm or more. [4] a bonding step of bonding the adhesive tape for electronic component processing to a first surface of a substrate to be processed; a dicing step of dividing the substrate into a plurality of chips; an expanding step of stretching the adhesive tape for electronic component processing to widen the spaces between the chips; a pick-up step of picking up the chip from the adhesive tape for electronic component processing; The method for manufacturing an electronic component includes the steps of: [5] The method for manufacturing an electronic component according to [4], wherein the dicing step divides the substrate into a plurality of chips using a laser guided by a water jet. [Explanation of symbols]

[0175] 1... Resin film 2 … Adhesive layer 10...Adhesive tape for electronic component processing

Claims

1. a resin film having a first surface and a second surface opposite to the first surface, being non-air permeable in a surface direction, and having through holes penetrating in a thickness direction; an adhesive layer having a non-porous structure, the adhesive layer being disposed on the first surface of the resin film; An adhesive tape for processing electronic components, comprising: The adhesive tape for processing electronic components has an elongation at break of 100% or more.

2. 2. The adhesive tape for processing electronic parts according to claim 1, wherein the resin film is non-absorbent to laser light.

3. 2. The adhesive tape for processing electronic parts according to claim 1, wherein the resin film has a thickness of 100 μm or more.

4. a bonding step of bonding the adhesive tape for electronic component processing according to any one of claims 1 to 3 to a first surface of a substrate to be processed; a dicing step of dividing the workpiece substrate into a plurality of chips; an expanding step of stretching the adhesive tape for electronic component processing to widen the spaces between the chips; a pick-up step of picking up the chip from the adhesive tape for electronic component processing; The method for manufacturing an electronic component includes the steps of:

5. The method for manufacturing an electronic component according to claim 4 , wherein the dicing step divides the substrate into a plurality of chips by a laser guided by a water jet.

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