Pressure-sensitive adhesive tape for processing electronic parts and process for producing electronic parts

Abstract

To provide a pressure-sensitive adhesive tape for processing an electronic component, which has a pressure-sensitive adhesive tape using a woven fabric as a base material and can suppress positional deviation during dicing by water jet laser processing.SOLUTION: An adhesive tape 10 for processing electronic components includes a base material 1 having a first surface S1 and a second surface S2 opposite to the first surface, and an adhesive layer 2 disposed on the first surface of the base material, wherein the base material is a woven fabric 20 including warps and wefts, and the woven fabric has a void area per inch of 2. 00mm2 or less in a first cross section taken along a warp direction in which the warps extend and a void area per inch of 2. LA or less in a second cross section taken along a weft direction in which the wefts extend.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 or chipping due to water splashing is likely to occur. Therefore, as described in Patent Documents 1 to 3, for example, porous substrates such as woven fabrics and nonwoven fabrics that are permeable to water are used as the substrates constituting the adhesive tape in water jet laser processing. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 3824874 [Patent Document 2] Patent No. 4087144 [Patent Document 3] Japanese Patent Application Laid-Open No. 2005-167042 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: adhesive tapes using a woven fabric as a substrate can prevent chipping and chip flying due to water splashing by allowing the woven fabric to permeate water, but gaps can sometimes form between the woven fabric side of the adhesive tape and the suction table. Air leakage from these gaps reduces the suction force of the suction table, resulting in misalignment during dicing. Because the woven fabric used as the substrate of adhesive tapes must be resistant to cutting during water jet laser processing, it is considered desirable for the threads constituting the fabric to have a large diameter. However, if the thread diameter is large, the gap between the woven fabric side of the adhesive tape and the suction table becomes larger, exacerbating the above-mentioned problem. As mentioned above, with the recent trend toward smaller, thinner, and more highly integrated chips, high precision is required for the accuracy of the misalignment of the cutting position during dicing.

[0008] The present disclosure has been made in consideration of the above-mentioned situation, and its main object is to provide an adhesive tape for processing electronic components that has a woven fabric as a substrate and is capable of suppressing misalignment during dicing. [Means for solving the problem]

[0009] One embodiment of the present disclosure is an adhesive tape for electronic component processing, comprising: a substrate having a first surface and a second surface opposing the first surface; and an adhesive layer disposed on the first surface of the substrate, wherein the substrate is a woven fabric including warp threads and weft threads, and the woven fabric has a first cross-section cut along a warp direction in which the warp threads extend and a second cross-section cut along a weft direction in which the weft threads extend, each having a gap area per inch of 2.00 mm or less. 2 The present invention provides the following adhesive tape for processing electronic components.

[0010] Another embodiment of the present disclosure provides an adhesive tape for electronic component processing, the adhesive tape having a substrate having a first surface and a second surface opposite to the first surface, and an adhesive layer disposed on the first surface of the substrate, wherein the substrate is a woven fabric including warp and weft threads, and when the substrate side surface of the adhesive tape for electronic component processing is vacuum-adsorbed onto a porous chuck table, the differential pressure between the inside of the porous chuck table and the atmosphere is -30 kPa or less.

[0011] Another embodiment of the present disclosure provides a method for manufacturing electronic components, comprising: an attachment step of attaching the above-mentioned adhesive tape for electronic component processing to a first surface of a workpiece substrate; a dicing step of dividing the workpiece substrate into a plurality of chips; and a peeling step of peeling the adhesive tape for electronic component processing from the chips. [Effects of the Invention]

[0012] The present disclosure can provide an adhesive tape for processing electronic components that can suppress misalignment during dicing. [Brief explanation of the drawings]

[0013] [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 and 1B are schematic plan and cross-sectional views illustrating examples of woven fabrics constituting an adhesive tape for processing electronic components according to the present disclosure. [Figure 3] 1A to 1C are process diagrams illustrating a dicing process using an adhesive tape for processing electronic components according to the present disclosure. [Figure 4] 1A to 1C are process diagrams illustrating a conventional dicing process using adhesive tape. [Figure 5] FIG. 10 is a schematic diagram for calculating the gap area of ​​the first cross section and the gap area of ​​the second cross section. [Figure 6] 1 is a schematic cross-sectional view illustrating an example of an adhesive tape for processing electronic components according to the present disclosure. [Figure 7] 1A to 1C are process diagrams illustrating a method for manufacturing an electronic component according to the present disclosure. [Figure 8] 1A to 1C are process diagrams illustrating a method for manufacturing an electronic component according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] 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.

[0015] 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.

[0016] Furthermore, in this specification, "film" and "sheet" are not distinguished from each other solely based on the difference in name.

[0017] The adhesive tape for processing electronic components and the method for manufacturing electronic components according to the present disclosure will be described below. The adhesive tape for processing electronic components according to the present disclosure can be broadly divided into a first embodiment and a second embodiment.

[0018] A. Adhesive tape for electronic component processing A-1. First embodiment The adhesive tape for electronic component processing in this embodiment is an adhesive tape for electronic component processing, comprising: a substrate having a first surface and a second surface opposite to the first surface; and an adhesive layer disposed on the first surface of the substrate, wherein the substrate is a woven fabric including warp threads and weft threads, and the woven fabric has a first cross section cut along the warp direction in which the warp threads extend and a second cross section cut along the weft direction in which the weft threads extend, each having a gap area per inch of 2.00 mm or less. 2 The following is the result.

[0019] Fig. 1 is a schematic cross-sectional view illustrating an example of an adhesive tape for processing electronic components according to this embodiment. As illustrated in Fig. 1, the adhesive tape for processing electronic components 10 includes a substrate 1 having a first surface S1 and a second surface S2 opposing the first surface S1, and an adhesive layer 2 disposed on the first surface S1 of the substrate 1. The substrate 1 is a woven fabric 20.

[0020] 2(a) to 2(d) are schematic plan views and cross-sectional views illustrating examples of woven fabrics in the adhesive tape for electronic component processing according to this embodiment. Fig. 2(b) is an enlarged view of Fig. 2(a). Fig. 2(c) is a first cross-sectional view taken along the warp direction D1 (YY) of Fig. 2(b), and Fig. 2(d) is a second cross-sectional view taken along the weft direction D2 (XX) of Fig. 2(b). As shown in Figs. 2(a) to 2(d), woven fabric 20 is composed of warp yarns 21 and weft yarns 22.

[0021] In the woven fabric 20 of this embodiment, the gap area per inch of a first cross section cut along the warp direction D1 in which the warp threads 21 extend, and the gap area per inch of a second cross section cut along the weft direction D2 in which the weft threads 22 extend are each less than a predetermined value.

[0022] 3(a) and 3(b) are process diagrams illustrating an example of a dicing process using the adhesive tape for electronic component processing according to this embodiment. First, as shown in FIG. 3(a), a ring frame 31 is attached to the adhesive layer surface of the adhesive tape for electronic component processing 10, and a workpiece substrate 11 is attached to the adhesive layer surface of the adhesive tape for electronic component processing 10, thereby securing the workpiece substrate 11 to the adhesive tape for electronic component processing 10. Next, the workpiece substrate 11 secured to the adhesive tape for electronic component processing 10 is secured to a suction table 32 by vacuum suction. Next, as shown in FIG. 3(b), the workpiece substrate 11 is divided into chips 12.

[0023] When dicing a substrate to be processed using water jet laser processing, it is necessary to ensure that the substrate does not break during the water jet laser processing. Therefore, when using a woven fabric as the substrate, it is desirable that the threads constituting the woven fabric have a relatively large diameter. FIG. 4 is a schematic cross-sectional view illustrating a conventional adhesive tape having a woven fabric as a substrate, in which a substrate to be processed is fixed to a suction table by suction during a dicing process. As shown in FIG. 4, the adhesive tape 100 includes a woven fabric 101 as a substrate and an adhesive layer 102. Because the surface of the woven fabric 101 has irregularities, a gap is formed between the surface of the adhesive tape 100 facing the woven fabric 101 and the suction table 32. If the threads constituting the woven fabric 101 have a large diameter, the irregularities on the surface of the woven fabric 101 become larger, resulting in a larger gap between the surface of the adhesive tape 100 facing the woven fabric 101 and the suction table 32. Such a large gap reduces the suction force of the suction table 32 due to air leakage through the gap. Furthermore, if the diameter of the threads constituting the woven fabric 101 is large, the voids become large in a cross section cut in the thickness direction of the woven fabric 101. If the woven fabric 101 has large voids in the cross section, the breathability in the plane direction of the woven fabric 101 increases, and air leaks from the edge of the woven fabric 101 or from the cut portion 13 of the workpiece substrate 11 through the woven fabric 101, thereby reducing the suction force of the suction table 32. Thus, the inventors of the present disclosure have discovered a new problem with conventional adhesive tapes having a woven fabric as a base material: air leakage reduces the suction force of the suction table, causing misalignment during dicing.

[0024] In the present disclosure, a woven fabric is used as the substrate, in which the void area per inch of a first cross section cut along the warp direction (in which the warp threads extend) and the void area per inch of a second cross section cut along the weft direction (in which the weft threads extend) are each below a predetermined value. This reduces the gap between the substrate-side surface of the adhesive tape for electronic component processing and the suction table. Furthermore, because the substrate is a woven fabric, although the substrate is breathable in the surface direction, air leakage from the edge of the substrate and from the cut portion of the substrate to be processed can be suppressed. This prevents a decrease in the suction force of the suction table due to air leakage, and suppresses positional deviation during dicing. Specifically, it suppresses deviation of the cutting position during dicing.

[0025] Therefore, the adhesive tape for processing electronic parts according to this embodiment can be suitably used when dicing a substrate to be processed by water jet laser processing.

[0026] Hereinafter, each component of the adhesive tape for processing electronic components according to this embodiment will be described.

[0027] 1. Base material The substrate in this embodiment is a woven fabric containing warp and weft threads, and is a member that supports the adhesive layer. The woven fabric has water permeability, that is, water permeability.

[0028] (1) Fabric type As shown in Figures 2(a) to 2(d), the woven fabric 20 is composed of warp threads 21 and weft threads 22. In plan view, the woven fabric 20 has openings 23 surrounded by the warp threads 21 and weft threads 22, and non-openings 24 that have the warp threads 21 and weft threads 22 but are not the openings 23. In Figures 2(a) to 2(d), a1 indicates the diameter of the warp threads 21, a2 indicates the diameter of the weft threads 22, b1 indicates the opening between the warp threads 21, and b2 indicates the opening between the weft threads 22.

[0029] In the woven fabric 20 of this embodiment, the gap area per inch of the first cross section cut along the warp direction D1 in which the warp yarns 21 extend, and the gap area per inch of the second cross section cut along the weft direction D2 in which the weft yarns 22 extend are each 2.00 mm 2 Less than or equal to 1.50mm 2 It may be less than 1.00 mm 2 On the other hand, in the woven fabric, the void area per inch of the first cross section and the void area per inch of the second cross section may each be, for example, 0.10 mm 2 or more, 0.30 mm 2 It may be more than 0.50 mm 2 That is, in the woven fabric, the void area per inch of the first cross section and the void area per inch of the second cross section may be, for example, 0.10 mm 2 Over 2.00mm 2 Less than 0.30mm 2 Over 1.50mm 2 May be less than 0.50 mm 2 Over 1.00mm 2 It may be the following:

[0030] When calculating the gap area per inch of a first cross section of the woven fabric 20 cut along the warp direction D1 in which the warp yarns 21 extend, the first cross section of the woven fabric 20 actually has the warp yarns 21 and weft yarns 22 positioned alternately above and below, as shown in FIG. 2(c), but a model is assumed in which the warp yarns 21 are positioned below and the weft yarns 22 are positioned above, as shown in FIG. 5(a). In the model shown in FIG. 5(a), the weft yarns 22 are considered to be perfectly circular and the warp yarns 21 are considered to be arranged linearly in the first cross section of the woven fabric 20 cut along the warp direction D1 in which the warp yarns 21 extend. In FIG. 5(a), D3 is the thickness direction of the woven fabric 20. The gap area S11 per inch of the first cross section is calculated using the following formula (1): S11=S1-(S121+S122) Formula (1) (In the above formula (1), S1 represents the total area per inch of the first cross section, S121 represents the area of ​​the warp yarn per inch of the first cross section, and S122 represents the area of ​​the weft yarn per inch of the first cross section.)

[0031] The total area S1 per inch of the first cross section is calculated by the following formula (2). S1=T av ×1 formula (2) (In the above formula (2), T av indicates the average thickness of the fabric.)

[0032] The area S121 of the warp yarns per inch in the first cross section is calculated by the following formula (3). S121=a1 av ×1 formula (3) (In the above formula (3), a1 av indicates the average diameter of the warp yarn.)

[0033] The area S122 of the weft yarn per inch in the first cross section is calculated by the following formula (4). S122=n2×(π×(a2 av / 2) 2 ) Formula (4) (In the above formula (4), a2 av is the average diameter of the weft yarn, and n2 is the average number of weft yarns per inch in the first cross section.)

[0034] Similarly, when calculating the gap area per inch of a second cross section of the woven fabric 20 cut along the weft direction D2 in which the weft yarn 22 extends, the warp yarns 21 and the weft yarns 22 are actually positioned alternately above and below each other in the second cross section of the woven fabric 20, as shown in FIG. 2(d), for example. However, a model is assumed in which the weft yarns 22 are positioned below and the warp yarns 21 are positioned above, as shown in FIG. 5(b). In the model shown in FIG. 5(b), the warp yarns 21 are considered to be perfectly circular and the weft yarns 22 are considered to be arranged linearly in the second cross section of the woven fabric 20 cut along the weft direction D2 in which the weft yarns 22 extend. The gap area S12 per inch of the second cross section is then calculated using the following formula (5): S12=S2-(S221+S222) Formula (5) (In the above formula (5), S2 represents the total area per inch of the second cross section, S221 represents the area of ​​the warp yarn per inch of the second cross section, and S222 represents the area of ​​the weft yarn per inch of the second cross section.)

[0035] The total area S2 per inch of the second cross section is calculated by the following formula (6). S2=T av ×1 formula (6) (In the above formula (6), T av indicates the average thickness of the fabric.)

[0036] The area S221 of the warp yarns per inch of the second cross section is calculated by the following formula (7). S221=n1×(π×(a1 av / 2) 2 ) Formula (7) (In the above formula (7), a1 av is the average diameter of the warp threads, and n1 is the average number of warp threads per inch in the first cross section.)

[0037] The area S222 of the weft yarn per inch in the second cross section is calculated by the following formula (8). S222=a2 av ×1 formula (8) (In the above formula (8), a2 av indicates the average diameter of the weft yarn.)

[0038] Methods for adjusting the void area of ​​the first cross section and the void area of ​​the second cross section to a predetermined value or less include increasing the mesh size (number of threads per inch) of the fabric, reducing the thread diameter, calendering the fabric, and using a plain weave for the fabric. When the mesh size of the fabric is large, the void area of ​​the first cross section and the void area of ​​the second cross section tend to be smaller. When the thread diameter is small, the void area of ​​the first cross section and the void area of ​​the second cross section tend to be smaller. When the fabric is calendered, the void area of ​​the first cross section and the void area of ​​the second cross section tend to be smaller. When the fabric is woven using a plain weave, the void area of ​​the first cross section and the void area of ​​the second cross section tend to be smaller.

[0039] In this embodiment, the yarn occupancy rate in the first cross section and the yarn occupancy rate in the second cross section may each be 66% or more, or 70% or more. Meanwhile, the yarn occupancy rate in the first cross section and the yarn occupancy rate in the second cross section may each be 95% or less, or 80% or less. That is, the yarn occupancy rate in the first cross section and the yarn occupancy rate in the second cross section may each be 66% or more and 95% or less, or 70% or more and 80% or less. When the yarn occupancy rate is a predetermined value or more, the void area in the first cross section and the void area in the second cross section tend to be less than a predetermined value. Furthermore, when the yarn occupancy rate is less than a predetermined value, sufficient water permeability is obtained. The yarn occupancy rate in the first cross section refers to the occupancy rate of the warp and weft yarns in the first cross section. Similarly, the yarn occupancy rate in the second cross section refers to the occupancy rate of the warp and weft yarns in the second cross section.

[0040] The occupancy rate C1 of the yarn in the first cross section is calculated by the following formula (9). C1={(S121+S122) / S1}×100 Formula (9) (In the above formula (9), S1 represents the total area per inch of the first cross section, S121 represents the area of ​​the warp yarn per inch of the first cross section, and S122 represents the area of ​​the weft yarn per inch of the first cross section.) The methods for determining the total area S1 per inch of the first cross section, the warp area S121 per inch of the first cross section, and the weft area S122 per inch of the first cross section are as described above.

[0041] Similarly, the occupancy rate C2 of the yarn in the second cross section is calculated by the following formula (10). C2={(S221+S222) / S2}×100 Equation (10) (In the above formula (10), S2 represents the total area per inch of the second cross section, S221 represents the area of ​​the warp yarn per inch of the second cross section, and S222 represents the area of ​​the weft yarn per inch of the second cross section.) The methods for calculating the total area S2 per inch of the second cross section, the area S221 of the warp yarns per inch of the second cross section, and the area S222 of the weft yarns per inch of the second cross section are as described above.

[0042] Average diameter a1 of warp thread 21 av and the average diameter a2 of the weft yarn 22 av The average diameter a1 of the warp yarns 21 is not particularly limited as long as it is a diameter that can set the gap area of ​​the first cross section and the gap area of ​​the second cross section within the above ranges. av and the average diameter a2 of the weft yarn 22 av and may be, for example, 20 μm or more, 40 μm or more, or 60 μm or more. av and the average diameter a2 of the weft yarn 22 av are, for example, 130 μm or less, may be 105 μm or less, or may be 80 μm or less. av and the average diameter a2 of the weft yarn 22 av are, for example, 20 μm or more and 130 μm or less, 40 μm or more and 105 μm or less, or 60 μm or more and 80 μm or less. If the average wire diameter is a predetermined value or more, it is possible to prevent the fabric from being cut or weakened by the pressure of the water jet and the heat of the laser during water jet laser processing. Furthermore, if the average wire diameter is a predetermined value or less, the void area of ​​the first cross section and the void area of ​​the second cross section tend to be less than a predetermined value. Furthermore, if the average wire diameter is a predetermined value or less, sufficient water permeability can be obtained. Note that, when the yarn is multifilament, the average wire diameter of the yarn refers to the average wire diameter of the multifilament.

[0043] Here, the average diameter of the warp threads a1 av is the arithmetic mean value of the diameters of 10 randomly selected warp threads. Similarly, the average diameter of the weft threads, a2 avis the arithmetic mean value of the diameters of 10 randomly selected weft threads. The diameters of the warp threads and the weft threads are measured using a digital microscope, avoiding the intersections of the warp and weft threads. The digital microscope used can be the Keyence Digital Microscope VHX-2000.

[0044] The diameter of the warp threads may be one type or two or more types, and similarly, the diameter of the weft threads may be one type or two or more types.

[0045] The average number n1 of warp threads 21 per inch in the second cross section and the average number n2 of weft threads 22 per inch in the first cross section are each 80 or more, 100 or more, or 120 or more. Meanwhile, the average number n1 of warp threads 21 per inch in the second cross section and the average number n2 of weft threads 22 per inch in the first cross section are, for example, 500 or less, 300 or less, or 200 or less. That is, the average number n1 of warp threads 21 per inch in the second cross section and the average number n2 of weft threads 22 per inch in the first cross section are, for example, 80 or more and 500 or less, 100 or more and 300 or less, or 120 or more and 200 or less. When the average number is a predetermined value or more, the void area of ​​the first cross section and the void area of ​​the second cross section are easily within the above ranges. Furthermore, when the average number is a predetermined value or less, sufficient water permeability is obtained.

[0046] Here, the average number n1 of warp threads 21 per inch in the second cross section is the arithmetic mean value of the numbers of warp threads 21 per inch in 10 randomly selected second cross sections. Similarly, the average number n2 of weft threads 22 per inch in the first cross section is the arithmetic mean value of the numbers of weft threads 22 per inch in 10 randomly selected first cross sections.

[0047] The opening rate of the woven fabric is not particularly limited, but may be, for example, 10% or more, 20% or more, or 30% or more. The opening rate of the woven fabric may be, for example, 80% or less, 70% or less, or 60% or less. That is, the opening rate of the woven fabric may be, for example, 10% or more and 80% or less, 20% or more and 70% or less, or 30% or more and 60% or less. When the opening rate is a predetermined value or more, sufficient water permeability is obtained. When the opening rate is a predetermined value or less, sufficient adhesion to the adhesive layer is obtained.

[0048] The opening rate B (%) of the fabric is calculated by the following formula. B=[b1 av / (b1 av +a1 av )]×[b2 av / (b2 av +a2 av )] x 100 In the above formula, a1 av is the average diameter of the warp thread (μm), a2 av is the average diameter of the weft yarn (μm), b1 av is the average opening between warp threads (μm), b2 av indicates the average opening between weft yarns (μm).

[0049] The openings between warp threads and between weft threads are preferably smaller than the chip size, for example, on the order of millimeters or less. The average opening between warp threads and between weft threads is, for example, 500 μm or less, or may be 200 μm or less, or 100 μm or less. The average opening between warp threads and between weft threads is, for example, 20 μm or more, or 30 μm or more, or 40 μm or more. That is, the average opening between warp threads and between weft threads is, for example, 20 μm or more and 500 μm or less, or 30 μm or more and 200 μm or less, or 40 μm or more and 100 μm or less. If the average opening is a predetermined value or more, sufficient water permeability can be obtained. If the average opening is a predetermined value or less, sufficient adhesion to the adhesive layer can be obtained.

[0050] The average opening between warp threads is the arithmetic mean value of the opening between warp threads at 10 randomly selected locations. The average opening between weft threads is the arithmetic mean value of the opening between weft threads at 10 randomly selected locations. The opening between warp threads and the opening between weft threads are each measured using a digital microscope. The digital microscope that can be used is the Keyence Digital Microscope VHX-2000.

[0051] When measuring the diameter of the warp yarns, the diameter of the weft yarns, the opening between the warp yarns, and the opening between the weft yarns, the adhesive layer is removed from the adhesive tape for electronic component processing, and the woven fabric 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.

[0052] The warp and weft threads may each be monofilaments or multifilaments, with monofilaments being preferred because they are less likely to break during water jet laser processing.

[0053] In this embodiment, a woven fabric having the above-mentioned void area of ​​the first cross section and the void area of ​​the second cross section may be selected and used, or a woven fabric having the above-mentioned void area of ​​the first cross section and the void area of ​​the second cross section may be manufactured and used by subjecting the woven fabric to a calendaring process.

[0054] Calendering is a process in which a fabric is passed between two rolls at a constant speed, applying pressure and, if necessary, heat to the fabric. Calendering can reduce the thickness of the fabric, thereby making it possible to reduce the void area of ​​the first cross section and the void area of ​​the second cross section.

[0055] The load in the calendering process is not particularly limited as long as it can reduce the thickness of the woven fabric, and the temperature in the calendering process is not particularly limited as long as it can reduce the thickness of the woven fabric and is lower than the melting point of the material of the woven fabric.

[0056] The surface of the fabric 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, and alkali treatment.

[0057] Average thickness of fabric T av The average thickness T of the woven fabric is not particularly limited as long as it can support the adhesive layer. av is, for example, 30 μm or more, and may be 50 μm or more. av is preferably 250 μm or less, more preferably 200 μm or less. av For example, the average thickness of the woven fabric may be 30 μm or more and 250 μm or less, or 50 μm or more and 200 μm or less. If the average thickness of the woven fabric is within the above range, the void area of ​​the first cross section and the void area of ​​the second cross section described above can be reduced.

[0058] Average thickness of fabric T av is measured using a thickness gauge such as a dial thickness gauge or digital thickness gauge, and is the arithmetic mean value of the thickness at 10 randomly selected points.

[0059] When measuring the thickness of the woven fabric, the adhesive layer is removed from the adhesive tape for processing electronic components, and the woven fabric is taken out. The method for removing the adhesive layer is as described above.

[0060] The weaving method of the woven fabric is not particularly limited, and examples thereof include plain weave, twill weave, and satin weave. Among these, plain weave is preferred because it allows the thickness of the woven fabric to be thin and makes it easier to obtain the above-mentioned ranges of void area in the first cross section and void area in the second cross section.

[0061] (2) Characteristics of fabrics The woven fabric of this embodiment has the above-described void area of ​​the first cross section and the void area of ​​the second cross section, and therefore has reduced air permeability in the plane direction. The reduced air permeability of the woven fabric of this embodiment can be confirmed by the following method. First, the woven fabric is cut into a size of 210 mm x 210 mm to obtain a test piece. The woven fabric is placed on a 200 mm diameter ceramic porous chuck table of a HARMOTECH tape remover "HTR0608-1," and a 50 μm thick polyethylene terephthalate (PET) film is placed on the fabric, and vacuum suction is initiated. During vacuum suction, a ULVAC vacuum pump "DA-20D" is used. During vacuum suction, 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. For the woven fabric of this embodiment, the differential pressure is preferably -25 kPa or less, more preferably -40 kPa or less, and even more preferably -60 kPa or less.

[0062] As will be described later, when the adhesive layer is an energy ray-curable adhesive layer, the woven fabric preferably transmits energy rays. The energy ray transmittance of the woven fabric is, for example, 50% or more, or may be 70% or more, or 90% or more. When the energy transmittance of the woven fabric is high within the above range, reflection of energy rays by the woven fabric can be suppressed when the adhesive tape for electronic component processing is irradiated with energy rays from the woven fabric side to cure the adhesive layer. This can suppress poor curing of the adhesive layer. On the other hand, there is no particular upper limit for the energy transmittance of the woven fabric.

[0063] In this specification, the energy ray transmittance refers to the transmittance of the energy ray used when irradiating the energy ray-curable adhesive layer with energy rays to cure it. For example, when ultraviolet rays are used, the ultraviolet irradiation device often uses a high-pressure mercury lamp or an electrodeless lamp that reproduces the spectrum of a high-pressure mercury lamp. The dominant wavelength of a high-pressure mercury lamp is 365 nm. Therefore, in this case, the energy ray transmittance refers to the transmittance at a wavelength of 365 nm.

[0064] (3) Textile materials The woven material preferably has high transmittance to the laser light used in water jet laser processing. Examples of woven materials include chemical fibers, natural fibers, and inorganic fibers. Examples of chemical fiber materials include polyolefin, polyester, polyamide, polycarbonate, acrylic resin, polyvinyl chloride, polyurethane, polystyrene, styrene-ethylene-butene copolymer, styrene-ethylene-pentene copolymer, rayon, and cellulose acetate. Examples of polyolefins include polyethylene, polypropylene, polybutene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-methyl methacrylate copolymer (EMMA), and ionomer. Examples of polyesters include polyethylene terephthalate. Examples of polyamides include nylon 6, nylon 6,6, nylon 12, and aramid. Examples of natural fiber materials include cotton, silk, and wool. Examples of inorganic fibers include glass fiber and carbon fiber. These may be used alone or in combination.

[0065] 2. Adhesive layer The adhesive layer in this embodiment 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] (1) 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] (a) 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] (b) 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] (c) 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 woven fabric.

[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 a polymerization reaction of the energy ray-curable compound. Therefore, even with a small amount of energy ray irradiation, the energy ray-curable compound can be efficiently cured and easily peeled off. Furthermore, as mentioned above, resins and the like can be used for the textile, and many resins 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 the energy rays that have transmitted through the textile.

[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] (d) 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] (e) 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] (f) 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 woven fabric is placed on the adhesive layer to obtain an adhesive tape for processing electronic components, which has the woven fabric, adhesive layer, and separator in this order.

[0101] (2) 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, when a low-adhesion adhesive layer exhibits low adhesion, it means that the adhesive layer exhibits adhesive strength sufficient to sufficiently fix the substrate to be processed and the chip to the adhesive tape for electronic component processing during the dicing process, and sufficient adhesive strength sufficient 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] (a) 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, the (meth)acrylic acid ester copolymer containing 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, 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] (b) 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] (c) 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] (d) 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 50 μm or more. The first and second surfaces of the fabric tend to be uneven. By ensuring that the thickness of the adhesive layer is at least a predetermined value, the unevenness of the first surface of the fabric can be smoothed out. This improves adhesion between the adhesive sheet for electronic components and the substrate or chip to be processed, thereby suppressing chipping during water jet laser processing. Furthermore, if the adhesive layer is too thin, adhesion to the fabric may be reduced. Furthermore, if the adhesive layer is too thin, oxygen inhibition from the fabric side of the adhesive layer may result in poor curing. 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] As illustrated in Figure 6, the thickness T2 of the adhesive layer 2 is the length from the reference plane S to the outermost surface of the adhesive layer 2 on the opposite side to the fabric 20, when the outermost surface of the adhesive layer 2 on the fabric 20 side is taken as the reference plane S.

[0122] 3. Other configurations The adhesive tape for processing electronic parts in this embodiment may have other components in addition to the above-mentioned substrate and adhesive layer, if necessary.

[0123] The pressure-sensitive adhesive tape for processing electronic parts in this embodiment may have a separator on the surface of the pressure-sensitive adhesive layer opposite to the substrate.

[0124] 4. Characteristics of adhesive tape for electronic component processing (1) Vacuum suction The adhesive tape for electronic component processing in this embodiment has the above-mentioned woven fabric as a substrate, which can prevent a decrease in the suction force of the suction table due to air leakage and suppress misalignment during dicing. For example, in this embodiment, when the substrate side of the adhesive tape for electronic component processing is vacuum-sucked to the porous chuck table, the pressure difference between the inside of the porous chuck table and the atmosphere is preferably small. The pressure difference is preferably within the range described in the second embodiment described below.

[0125] (2) Peeling force (a) Energy ray curable adhesive layer When the adhesive layer is an energy ray-curable adhesive layer, the peel strength between the fabric 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.

[0126] 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.

[0127] 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.

[0128] When the adhesive layer is an energy ray-curable adhesive layer, the peel strength between the woven fabric and the adhesive layer in the adhesive tape for electronic component processing after irradiation with energy rays may be, for example, equal to or greater than the adhesive strength to a glass plate after irradiation with energy rays, and may be at least twice the adhesive strength to a glass plate after irradiation with energy rays. When the peel strength is within the above range, the adhesion between the woven fabric and the adhesive layer after irradiation with energy rays is high, thereby preventing 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 woven fabric and the adhesive layer after irradiation with energy rays is very high, the peel strength between the woven fabric 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 woven fabric and the adhesive layer after irradiation with energy rays described below, and peeling may not occur between the woven fabric and the adhesive layer.

[0129] Here, the peel strength between the woven fabric 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 woven fabric, an adhesive layer, and a separator in this order. If the adhesive tape for electronic component processing does not have a separator on the side of the adhesive layer opposite the woven fabric, a separator is placed on the side of the adhesive layer opposite the woven fabric. 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 woven fabric 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 aging for 6 hours, a test specimen is prepared. Next, the fabric and adhesive layer of the test specimen are forcibly peeled in the longitudinal direction of the specimen. The edges of the peeled portion between the fabric and adhesive layer 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 fabric 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.

[0130] Examples of means for controlling the peel force between the woven fabric and the adhesive layer after irradiation with energy rays include adjusting the diameter of the woven fabric threads, applying a surface treatment to the woven fabric, 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 woven fabric and adhesive layer.

[0131] In a method of adjusting the diameter of the threads of a woven fabric, for example, when the thickness of the adhesive layer is constant, a smaller average diameter of the threads increases the contact area between the woven fabric and the adhesive layer, which improves adhesion between the woven fabric and the adhesive layer and tends to increase the peel force.

[0132] In addition, in the method of subjecting the fabric to a surface treatment, for example, the peeling force can be increased by subjecting the fabric to a surface treatment.

[0133] In addition, in the method of adjusting the thickness of the adhesive layer, when the average wire diameter of the threads of the woven fabric is constant, the thicker the adhesive layer, the larger the contact area between the woven fabric and the adhesive layer, which improves the adhesion between the woven fabric and the adhesive layer and tends to increase the above-mentioned peel force.

[0134] 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, when a tackifier is added, the peel force tends to be high.

[0135] In addition, in a method of adjusting the aging temperature when forming the adhesive layer or when laminating the woven fabric and the 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.

[0136] (b) Slightly adhesive adhesive layer When the adhesive layer is a weak adhesive layer, the peel strength between the fabric 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.

[0137] 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.

[0138] 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.

[0139] When the adhesive layer is a weak adhesive layer, the peel strength between the woven fabric 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 woven fabric 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 woven fabric and the adhesive layer after energy ray irradiation is very high, the peel strength between the woven fabric 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 woven fabric and the adhesive layer after energy ray irradiation described below, and peeling may not occur between the woven fabric and the adhesive layer.

[0140] The peel strength between the fabric 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 electronic component processing adhesive tape using a 2 kg roller (one round trip), and then cut to a width of 25 mm. The resulting adhesive tape is then aged for 6 hours to prepare a test specimen. Next, the fabric and adhesive layer of the test specimen are forcibly peeled along the length of the specimen. The edges of the peeled portion between the fabric and adhesive layer 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 fabric 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 is used as the tensile tester, for example.

[0141] Examples of means for controlling the peel force between the woven fabric and the adhesive layer include adjusting the diameter of the woven fabric thread, applying a surface treatment to the woven fabric, 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 woven fabric and adhesive layer.

[0142] The methods for adjusting the diameter of the threads of the woven fabric, the method for surface treating the woven fabric, the method for adjusting the thickness of the adhesive layer, and the method for adjusting the aging temperature when forming the adhesive layer or when laminating the woven fabric and the adhesive layer are the same as those for the above-mentioned energy ray-curable adhesive layer.

[0143] 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.

[0144] 5.Applications The adhesive tape for electronic component processing according to this embodiment can be used as a dicing tape. In particular, the adhesive tape for electronic component processing according to this embodiment can be suitably used as a dicing tape when dicing a substrate to be processed by laser processing. In particular, the adhesive tape for electronic component processing according to this embodiment can be suitably used as a dicing tape when dicing a substrate to be processed by water jet laser processing.

[0145] A-2. Second embodiment The adhesive tape for electronic component processing in this embodiment is an adhesive tape for electronic component processing having a substrate having a first surface and a second surface opposite to the first surface, and an adhesive layer arranged on the first surface of the substrate, wherein the substrate is a woven fabric including warp and weft threads, and when the substrate side surface of the adhesive tape for electronic component processing is vacuum-adsorbed onto a porous chuck table, the differential pressure between the inside of the porous chuck table and the atmosphere is -30 kPa or less.

[0146] Fig. 1 is a schematic cross-sectional view illustrating an example of an adhesive tape for processing electronic components according to this embodiment. As illustrated in Fig. 1, the adhesive tape for processing electronic components 10 includes a substrate 1 having a first surface S1 and a second surface S2 opposing the first surface S1, and an adhesive layer 2 disposed on the first surface S1 of the substrate 1. The substrate 1 is a woven fabric 20.

[0147] 2(a) to 2(d) are schematic plan views and cross-sectional views illustrating examples of woven fabrics in the adhesive tape for electronic component processing according to this embodiment. Fig. 2(b) is an enlarged view of Fig. 2(a). Fig. 2(c) is a first cross-sectional view taken along the warp direction D1 (YY) of Fig. 2(b), and Fig. 2(d) is a second cross-sectional view taken along the weft direction D2 (XX) of Fig. 2(b). As shown in Figs. 2(a) to 2(d), woven fabric 20 is composed of warp yarns 21 and weft yarns 22.

[0148] As described in the first embodiment above, the inventors of the present disclosure discovered a new problem with conventional adhesive tapes having a woven fabric as a base material: air leakage reduces the suction force of the suction table, causing misalignment during dicing.

[0149] In the present disclosure, when the substrate side surface of the adhesive tape for electronic component processing is vacuum-sucked to the porous chuck table, the differential pressure between the inside of the porous chuck table and the atmosphere is kept below a predetermined value, thereby preventing a decrease in the suction force of the suction table due to air leakage and preventing positional deviation during dicing. Specifically, deviation of the cutting position during dicing can be prevented.

[0150] Therefore, the adhesive tape for processing electronic parts according to this embodiment can be suitably used when dicing a substrate to be processed by water jet laser processing.

[0151] Hereinafter, each component of the adhesive tape for processing electronic components according to this embodiment will be described.

[0152] 1. Characteristics of adhesive tape for electronic component processing (1) Vacuum suction In this embodiment, when the substrate side surface of the adhesive tape for electronic component processing is vacuum-adsorbed onto the porous chuck table, the differential pressure between the inside of the porous chuck table and the atmosphere is −30 kPa or less, preferably −40 kPa or less, and more preferably −50 kPa or less. Meanwhile, the differential pressure may be, for example, −80 kPa or more, or −70 kPa or more, or even −60 kPa or more. That is, the differential pressure is −80 kPa or more to −30 kPa or less, preferably −70 kPa or more to −40 kPa or less, and more preferably −60 kPa or more to −50 kPa or less.

[0153] The differential pressure was measured as follows. First, the adhesive tape for electronic component processing was cut into a size of 210 mm x 210 mm to obtain a test piece. If the adhesive tape for electronic component processing had a separator on the adhesive layer opposite the substrate, the separator was removed. 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" with the substrate side of the adhesive tape facing the ceramic porous chuck table. A 50 μm thick polyethylene terephthalate (PET) film was then placed on the adhesive layer side of the adhesive tape for electronic component processing, and vacuum suction was initiated. If the adhesive tape for electronic component processing had a separator on the adhesive layer opposite the substrate, and the separator was a 50 μm thick polyethylene terephthalate (PET) separator, the PET separator was used without being removed. In this case, the PET separator was used as the 50 μm thick PET film. For vacuum suction, the vacuum pump used is the DA-20D vacuum pump manufactured by ULVAC, Inc. Under vacuum conditions, the differential pressure between the pressure inside the ceramic porous chuck table and atmospheric pressure is measured using a dial-type differential pressure gauge attached to the device.

[0154] Methods for adjusting the differential pressure to a predetermined value or less include increasing the mesh size (number of threads per inch) of the fabric, reducing the thread diameter, subjecting the fabric to calendering, and using a plain weave for the fabric. When the mesh size of the fabric is large, the differential pressure tends to be smaller. When the thread diameter is small, the differential pressure tends to be smaller. When the fabric is calendered, the differential pressure tends to be smaller. When the fabric is plain weave, the differential pressure tends to be smaller.

[0155] (2) Other characteristics Other properties of the adhesive tape for processing electronic components in this embodiment are the same as those described in detail in the first embodiment above.

[0156] 2. Base material The substrate in this embodiment is a woven fabric. The woven fabric is not particularly limited as long as the differential pressure between the inside of the porous chuck table and the atmosphere satisfies the above-mentioned range when the substrate-side surface of the adhesive tape for processing electronic components is vacuum-adsorbed onto the porous chuck table. However, a woven fabric having reduced air permeability in the surface direction is preferably used.

[0157] The suppression of breathability in the in-plane direction of the woven fabric was confirmed by the following method. First, the woven fabric was cut into a size of 210 mm x 210 mm to obtain a test piece. The woven fabric was placed on a 200 mm diameter ceramic porous chuck table of a tape remover "HTR0608-1" manufactured by Harmotec Corporation, and a 50 μm thick polyethylene terephthalate (PET) film was placed on the fabric, and vacuum suction was initiated. During vacuum suction, a vacuum pump "DA-20D" manufactured by ULVAC was used. During vacuum suction, the differential pressure between the inside of the ceramic porous chuck table and the atmosphere was measured using a dial-type differential pressure gauge attached to the device. In the woven fabric of this embodiment, the differential pressure is preferably −25 kPa or less, more preferably −30 kPa or less, and even more preferably −50 kPa or less.

[0158] Other features of the fabric of this embodiment are the same as those described in detail in the first embodiment above.

[0159] 3. Adhesive layer The adhesive layer in this embodiment is the same as that described in detail in the first embodiment above.

[0160] 4. Other configurations The adhesive tape for processing electronic components according to the present embodiment may have other components as needed in addition to the above-described woven fabric and adhesive layer. The adhesive tape for processing electronic components according to the present embodiment may have a separator on the surface of the adhesive layer opposite to the substrate.

[0161] 5.Applications The uses of the adhesive tape for processing electronic parts in this embodiment are the same as those described in detail in the first embodiment above.

[0162] B. Manufacturing methods for electronic components The method for manufacturing electronic components in the present disclosure includes an attachment step of attaching the above-mentioned adhesive tape for electronic component processing to one side of a workpiece substrate, a dicing step of dividing the workpiece substrate into a plurality of chips, and a peeling step of peeling the adhesive tape for electronic component processing from the chips.

[0163] 7(a) to 7(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. 7(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 31, 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. 7(b), a dicing process is performed in which the substrate 11 to be processed is divided into chips 12. Next, as shown in FIG. 7(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, when the adhesive layer of the adhesive tape 10 for electronic component processing is an energy ray-curable adhesive layer, as shown in FIG. 7(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 32 from the fabric side to harden and reduce the adhesive strength. Next, as shown in FIG. 7(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. This pick-up step is the peeling step. Next, as shown in Fig. 7(f), a mounting (die bonding) step is carried out in which the picked-up chip 12 is attached to a substrate 30.

[0164] 8(a) to 8(e) are process diagrams illustrating another example of a method for manufacturing an electronic component according to the present disclosure. First, as shown in FIG. 8(a), an attachment step is performed in which the adhesive layer surface of the adhesive tape 10 for electronic component processing is attached to a ring frame 31, and then a substrate 11 to be processed is attached to the adhesive layer surface of the adhesive tape 10 for electronic component processing. Next, as shown in FIG. 8(b), a dicing step is performed in which the substrate 11 is divided into chips 12. Next, as shown in FIG. 8(c), a transfer tape 40 is attached to the surface of the chip 12 opposite to the adhesive tape 10 for electronic component processing. Thereafter, if the adhesive layer of the adhesive tape 10 for electronic component processing is an energy ray-curable adhesive layer, an irradiation step is performed in which the adhesive layer of the adhesive tape 10 for electronic component processing is irradiated with energy rays 32 from the fabric side to harden and thereby reduce its adhesive strength, as shown in FIG. 8(d). 8(e), a transfer step is performed in which the adhesive tape 10 for processing electronic components is peeled off from the chip 12 and the ring frame 31, and the chip 12 and the ring frame 31 are transferred to the transfer tape 40. This transfer step is the peeling step.

[0165] In the present disclosure, since the above-described pressure-sensitive adhesive tape for processing electronic components is used, it is possible to suppress misalignment during the dicing process.

[0166] A general method can be applied to each step in the method for manufacturing an electronic component according to the present disclosure.

[0167] 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.

[0168] 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.

[0169] 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]

[0170] The present disclosure will be further described below with reference to examples and comparative examples.

[0171] [Comparative 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.

[0172] The woven fabric shown in Table 1 was used as the substrate. The pressure-sensitive adhesive composition was applied to a polyethylene terephthalate (PET) separator (Nippa Corporation's "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, a woven fabric was laminated onto the adhesive layer, and then aging was carried out at 40°C for 3 days. This produced an adhesive tape for processing electronic components having, in order, a woven fabric, an adhesive layer, and a separator.

[0173] In the woven fabric, the warp and weft yarns had the same diameter, and the mesh size in the weft direction and the mesh size in the warp direction were also the same. av (= average diameter of warp thread a1 av = average diameter of weft yarn a2 av), mesh size n (= average number of warp threads per inch in the second cross section n1 = average number of weft threads per inch in the first cross section n2), opening rate of the fabric, average opening between threads b av (=Average opening between warp threads b1 av = average opening between weft yarns b2 av ), the average thickness of the fabric T av and weaving method are shown in Table 1.

[0174] Then, the void area per inch in the second cross section was calculated using equation (5). S12=S2-(S221+S222) Formula (5) (In the above formula (5), S2 represents the total area per inch of the second cross section, S221 represents the area of ​​the warp yarn per inch of the second cross section, and S222 represents the area of ​​the weft yarn per inch of the first cross section.) In a woven fabric, the warp and weft threads have the same wire diameter, and the mesh size in the weft direction and the mesh size in the warp direction are also the same, so the gap area per inch in the first cross section and the gap area per inch in the second cross section are the same value.

[0175] Furthermore, the occupancy rate of the yarn in the second cross section was calculated using equation (10). C2 = {(S221 + S222) / S2} × 100(%) (In the above formula (10), S2 represents the total area per inch of the second cross section, S221 represents the area of ​​the warp yarn per inch of the second cross section, and S222 represents the area of ​​the weft yarn per inch of the second cross section.) In a woven fabric, the warp and weft threads have the same wire diameter, and the mesh size in the weft direction and the mesh size in the warp direction are also the same, so the yarn occupancy rate in the first cross section and the yarn occupancy rate in the second cross section are the same value.

[0176] [Example 1] An adhesive tape for processing electronic parts was produced in the same manner as in Example 1, except that the woven fabric used in Comparative Example 1 was subjected to a calendering process and used as the substrate.

[0177] [Examples 2 to 10] Adhesive tapes for electronic component processing were produced in the same manner as in Example 1, except that the woven fabrics shown in Table 1 were used as the substrate. In all of the woven fabrics, the warp and weft yarns had the same wire diameter, and the mesh openings in the weft and warp directions were the same.

[0178] [evaluation] (1) Degree of vacuum The adhesive tape for electronic component processing was cut to a size of 210 mm x 210 mm to obtain a test specimen. 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" with the fabric side facing the ceramic porous chuck table, and vacuum suction was initiated. A ULVAC vacuum pump, "DA-20D," was used for vacuum suction. 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 results are shown in Table 1.

[0179] (2) 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.

[0180] [Table 1]

[0181] It was confirmed that misalignment was suppressed when the gap area per inch of the first cross section of the woven fabric and the gap area per inch of the second cross section were equal to or less than a predetermined value, as in Examples 1 to 10. On the other hand, in Comparative Example 1, the gap area per inch of the first cross section of the woven fabric and the gap area per inch of the second cross section were larger than the predetermined values, resulting in a large misalignment of about 50 μm.

[0182] Furthermore, it was confirmed that misalignment was suppressed by keeping the differential pressure between the inside of the porous chuck table and the atmosphere at or below a predetermined value when the substrate side surface of the adhesive tape for electronic component processing was vacuum-adsorbed to the porous chuck table, as in Examples 1 to 10. On the other hand, in Comparative Example 1, the differential pressure was greater than the predetermined value, resulting in a large misalignment of about 50 μm.

[0183] Furthermore, a comparison between Comparative Example 1 and Example 1 confirmed that in the calendared fabric (Example 1), the gap area per inch of the first cross section and the gap area per inch of the second cross section can be set to a predetermined value or less, and that misalignment is more effectively suppressed than in the non-calendered fabric (Comparative Example 1).

[0184] The present disclosure provides the following inventions. [1] An adhesive tape for processing electronic components, comprising: a substrate having a first surface and a second surface opposite to the first surface; and an adhesive layer disposed on the first surface of the substrate, the substrate is a woven fabric including warp yarns and weft yarns, The woven fabric has a first cross section cut along the warp direction in which the warp yarns extend and a second cross section cut along the weft direction in which the weft yarns extend, each having a gap area per inch of 2.00 mm 2 The following is an adhesive tape for processing electronic components. [2] An adhesive tape for processing electronic components, comprising: a substrate having a first surface and a second surface opposite to the first surface; and an adhesive layer disposed on the first surface of the substrate, the substrate is a woven fabric including warp yarns and weft yarns, When the substrate side surface of the adhesive tape for electronic component processing is vacuum-adsorbed onto a porous chuck table, the differential pressure between the inside of the porous chuck table and the atmosphere is -30 kPa or less. [3] The adhesive tape for processing electronic components according to [1] or [2], wherein the thickness of the woven fabric is 250 μm or less. [4] The adhesive tape for electronic component processing according to any one of [1] to [3], wherein in the woven fabric, the occupancy rate of the warp threads and the weft threads in the first cross section and the occupancy rate of the warp threads and the weft threads in the second cross section are each 66% or more. [5] a step of attaching the adhesive tape for electronic component processing according to any one of [1] to [4] to a first surface of a substrate to be processed; a dicing step of dividing the substrate into a plurality of chips; a peeling step of peeling the adhesive tape for processing electronic components from the chip; The method for manufacturing an electronic component includes the steps of: [6] The method for manufacturing an electronic component according to [5], wherein the dicing step divides the substrate to be processed into a plurality of chips using a laser guided by a water jet. [Explanation of symbols]

[0185] 1 … Base material 2 … Adhesive layer 20… Textiles 21... Warp threads 22... Weft thread 10...Adhesive tape for electronic component processing

Claims

1. An adhesive tape for processing electronic components, comprising: a substrate having a first surface and a second surface opposite to the first surface; and an adhesive layer disposed on the first surface of the substrate, the substrate is a woven fabric including warp yarns and weft yarns; In the woven fabric, the gap area per inch of a first cross section cut along the warp direction in which the warp yarns extend and the gap area per inch of a second cross section cut along the weft direction in which the weft yarns extend are each 2.00 mm ２ The following is an adhesive tape for processing electronic components.

2. An adhesive tape for processing electronic components, comprising: a substrate having a first surface and a second surface opposite to the first surface; and an adhesive layer disposed on the first surface of the substrate, the substrate is a woven fabric including warp yarns and weft yarns; When the substrate side surface of the adhesive tape for electronic component processing is vacuum-adsorbed onto a porous chuck table, a differential pressure between the inside of the porous chuck table and the atmosphere is −30 kPa or less.

3. 3. The adhesive tape for processing electronic components according to claim 1, wherein the woven fabric has a thickness of 250 μm or less.

4. 3. The adhesive tape for electronic component processing according to claim 1, wherein in the woven fabric, the occupancy rate of the warp threads and the weft threads in the first cross section and the occupancy rate of the warp threads and the weft threads in the second cross section are each 66% or more.

5. a bonding step of bonding the adhesive tape for electronic component processing according to any one of claims 1 to 4 to a first surface of a substrate to be processed; a dicing step of dividing the workpiece substrate into a plurality of chips; a peeling step of peeling the adhesive tape for electronic component processing from the chip; The method for manufacturing an electronic component includes the steps of:

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

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