TW201923861A - Thermal peeling method for machining inspection objects - Google Patents

Abstract

A thermal peeling method for machining inspection objects, the method including steps (I) and (II) below. Step (I): a step for sticking a plurality of machining inspection objects to an adhesive surface of an adhesive layer (X1) of an adhesive sheet that includes the adhesive layer (X1) and a non-adhesive, thermally expandable base material that includes a resin and thermally expandable particles. Step (II): a step for heating a portion of the thermally expandable base material to at least the temperature at which the thermally expandable particles expand and selectively peeling off a portion of the plurality of machining inspection objects.

Description

Heat peeling method for processing inspection object

The present invention relates to a thermal peeling method for processing an inspection object. More specifically, the present invention relates to a method for selectively heating and peeling a part of a processing inspection object temporarily fixed to an adhesive sheet.

The adhesive sheet is used not only for the purpose of semi-permanently fixing members, but also for temporarily fixing such applications when processing building materials, interior decoration materials, and electronic parts. In such an adhesive sheet for temporary fixing purposes, it is required to have both adhesiveness to the adherend during use (temporary fixation) and peelability of the adherend after use.

For example, Patent Document 1 discloses an adhesive sheet for use in cutting an electronic component. This adhesive sheet is provided on at least one side of a substrate, and is provided with a thermally expandable adhesive layer containing thermally expandable particles. In addition, with respect to the thickness of the heat-expandable adhesive layer, the maximum thickness of the heat-expandable particles is adjusted with respect to the thickness of the heat-expandable adhesive layer, and the average roughness of the centerline of the surface of the heat-expandable adhesive layer before heating is adjusted to 0.4 μm or less. Patent Document 1 describes that the adhesive sheet can ensure the contact area with the adherend when the electronic component is cut (at the time of temporary fixation), and can exhibit the adhesiveness that can prevent bonding failures such as wafer scattering. In addition, it is described in the purpose after use (after the electronic component is cut) that the thermally expandable particles are expanded by heating, the contact area with the adherend can be reduced, and the object can be easily peeled off. Prior Art Literature Patent Literature

Patent Document 1: Japanese Invention Patent No. 3985853

Problems to be solved by the invention

However, as in the heat-peeling type adhesive sheet disclosed in Patent Document 1, when the adherend is peeled off from the adhesive sheet, heat treatment is applied to the entire surface of the adherend, so that all of the adherend is peeled off at one time. Use it like this. However, in recent years, when heat peeling is performed, among a plurality of adherends attached to an adhesive sheet, only a part of the adherend is peeled off, and there is an increasing demand for keeping the remainder in a state of being adhered to the adhesive sheet. Specifically, for example, the processing steps of FPC (Flexible Printed Circuit) parts in which a thin layer of copper foil and a polyimide film are laminated include attaching parts on a heat-peeling type adhesive sheet, After fixing and applying the cutting process, the entire surface of the adhesive sheet is heat-treated, and after all the parts are peeled off, a part of the cut pieces of the part is moved and separated. In this step, the vibration system that occurs when a part of the cutting pieces is moved and separated causes the other cutting pieces to deform or fall off. In the dicing step of the semiconductor wafer or the multilayer capacitor, after the dicing process, the heat-peeling type adhesive sheet holding the adherend is heated to peel off the adherend. The problem that the adherends of the object are separated from the adhesive sheet as a whole. In addition, due to the vibrations that occur during the movement and separation of the adherend after processing, there is a problem that the position of the adherend remaining on the adhesive sheet shifts or falls off. Furthermore, according to the inspection results of a plurality of adherends, there is also a requirement that only a part of the adherend is peeled off, and the remainder wants to maintain the state of being adhered to the adhesive sheet. Therefore, it is conceivable to temporarily fix the adherend (hereinafter, also referred to as a "process inspection object") to be adhered to at least one of processing and inspection using a heat-peelable adhesive sheet disclosed in Patent Document 1, and implement After at least one of processing and inspection, by partially heating the adhesive sheet, a part of the plurality of processing inspection objects attached to the adhesive sheet is selectively peeled off, and the remaining processing inspection objects are The state of being adhered to the adhesive sheet is thereby considered to prevent deformation, positional deviation, and positional deviation of the processing inspection object remaining on the adhesive sheet due to vibrations that occur during the movement and separation of the processing inspection object. It is thought that it can also respond to the request that only a part of the processing inspection object is peeled off according to the inspection result, and the remaining processing inspection object wants to maintain the state of being attached to the adhesive sheet.

However, when the adhesive sheet disclosed in Patent Document 1 contains thermally expandable particles in the adhesive layer, residues from the thermally expandable particles adhere to the surface of the object to be inspected for processing or are caused by the expansion of the thermally expandable particles. The adhesive layer is deformed, and a part of the adhesive layer adheres (so-called "residual glue") to the surface of the processing inspection object, which may contaminate the surface of the processing inspection object after heat peeling.

An object of the present invention is to provide a method for heating and peeling a processing inspection object using an adhesive sheet, in which residues from heat-expandable particles are prevented from adhering to the surface of the processing inspection object or due to residues on the surface of the processing inspection object. Due to the contamination on the surface of the processing inspection object after the heat peeling, at the same time, a desired portion can be selectively heated and peeled among the plurality of processing inspection objects attached to the adhesive sheet. Means of solving the problem

The present inventors have found that by using an adhesive sheet having a non-adhesive heat-expandable substrate and an adhesive layer, the non-adhesive heat-expandable substrate contains a resin and heat-expandable particles, and the above-mentioned problems can be solved.

That is, this invention relates to the following [1]-[14]. [1] A method for heating and peeling an object to be processed and inspected, which comprises the following steps (I) and (II), and step (I): a non-adhesive thermally expandable substrate and an adhesive layer (X1) A step of attaching a plurality of objects to be inspected on the adhesive surface of the adhesive layer (X1) of the adhesive sheet, the non-adhesive thermally expandable substrate contains resin and thermally expandable particles, step (II): the aforementioned thermally expandable substrate A step of heating a part of the material to a temperature at which the thermally expandable particles expand or more, and selectively peeling a part of the plurality of processing inspection objects. [2] The method according to [1], wherein the step (I) has the following steps (I-1) to (I-2), and the step (I-1): on the adhesive layer (X1) of the aforementioned adhesive sheet Step of attaching a piece of processing inspection object before slicing on the adhesive surface of step), Step (I-2): slicing the piece of processing inspection object before the singulation on the adhesive surface step. [3] The method according to [1] or [2], wherein the adhesive sheet has an adhesive layer (X2) on the opposite side of the side of the thermally expandable substrate laminated with the adhesive layer (X1). The double-sided adhesive sheet is used by attaching a hard support on the adhesive surface of the adhesive layer (X2) of the double-sided adhesive sheet. [4] The method according to [3], wherein step (I) has the following steps (I-A1) to (I-A3), and step (I-A1): placing a plurality of semiconductor wafers on the adjacent semiconductors A step of setting a gap between the wafers and placing them on the adhesive surface of the adhesive layer (X1), step (I-A2): covering the plurality of semiconductor wafers and a peripheral portion of the plurality of semiconductor wafers with a packaging material The step of adhering the surface to harden the packaging material to obtain the package in which the plurality of semiconductor wafers are packaged in the hardened packaging material. Step (I-A3): a step of singulating the package in units of the semiconductor wafer. . [5] The method according to [1] or [2], wherein the adhesive sheet is used by attaching a frame member having an opening formed on an adhesive surface of the adhesive layer (X1). [6] The method according to [5], wherein step (I) has the following steps (I-B1) to (I-B3), and step (I-B1): placing a plurality of semiconductor wafers on the adjacent adjacent semiconductor A step of setting a gap between the wafers and placing them on the adhesive surface of the adhesive layer (X1) exposed from the opening of the frame member, step (I-B2): covering the plurality of semiconductor wafers with a packaging material and The step of hardening the packaging material to obtain the package formed by hardening the packaging material on the adhesive surfaces of the peripheral portions of the plurality of semiconductor wafers. Step (I-B3): the semiconductor wafer unit The step of singulating the aforementioned package. [7] The method according to any one of [1] to [6], wherein the heating in step (II) is performed on the opposite side of the thermally expandable substrate from the side laminated with the adhesive layer (X1). . [8] The method according to any one of [1] to [7], wherein the thermally expandable base material satisfies the following requirement (1), • requirement (1): storage modulus E '(23 at 23 ° C) ) Is 1.0 × 10 ⁶ Pa or more. [9] The method according to any one of [1] to [8], wherein the thermally expandable base material satisfies the following requirements (2), • requirement (2): storage modulus E '(100 at 100 ° C) ) Is 2.0 × 10 ⁵ Pa or more. [10] The method according to any one of [1] to [9], wherein the expansion start temperature (t) of the thermally expandable particles is 120 to 250 ° C, and the thermally expandable substrate satisfies the following requirement (3) Requirement (3): The storage modulus E '(t) at the expansion start temperature (t) is 1.0 × 10 ⁷ Pa or less. [11] The method according to any one of [1] to [10], wherein the storage shear modulus G '(23) of the adhesive layer (X1) at 23 ° C is 1.0 × 10 ⁴ to 1.0 × 10 ⁸ Pa. [12] The method according to any one of [1] to [11], wherein the ratio of the thickness of the thermally expandable substrate to the thickness of the adhesive layer (X1) at 23 ° C (thermally expandable substrate / adhesion) The agent layer (X1)) is 0.2 or more. [13] The method according to any one of [1] to [12], wherein the thickness of the thermally expandable substrate at 23 ° C. is 10 to 1000 μm, and the thickness of the adhesive layer (X1) is 1 to 60 μm. [14] The method according to any one of [1] to [13], wherein the probe viscosity value on the surface of the thermally expandable substrate is less than 50 mN / 5 mmφ. [15] The method according to any one of the above [1] to [14], wherein the thermally expandable particles have an average particle diameter before expansion at 23 ° C. of 3 to 100 μm. Effect of the invention

According to the present invention, it is possible to suppress the contamination of residues from heat-expandable particles on the surface of a processing inspection object or to remove contamination on the surface of a processing inspection object caused by heat-resistance caused by the residue on the surface of the processing inspection object. Among the plurality of processing inspection objects of the sheet, a desired portion is selectively peeled by heating.

Implementation of the invention

In the present invention, the "active ingredient" refers to a component obtained by removing a diluted solvent from components contained in a target composition. In addition, the mass average molecular weight (Mw) is a value converted into a standard polystyrene measured by a gel permeation chromatography (GPC) method, and specifically a value measured by a method described in Examples.

In the present invention, for example, "(meth) acrylic acid" means both "acrylic acid" and "methacrylic acid", and other similar terms are also the same. In addition, regarding the preferable numerical range (for example, the range of the content, etc.), the lower limit value and the upper limit value may be described independently in combination. For example, according to the description of "preferably 10 to 90, more preferably 30 to 60", it is also possible to combine "better lower limit (10)" and "better upper limit (60)" to become " 10 ~ 60 ".

<Thermal peeling method of the processing inspection object> (1) The thermal peeling method of the processing inspection object of this embodiment has the following steps (I) and (II), and (1): a non-adhesive thermally expandable substrate and A step of attaching a plurality of objects to be inspected on the adhesive surface of the adhesive layer (X1) of the adhesive sheet of the adhesive layer (X1). The non-adhesive thermally expandable substrate contains resin and thermally expandable particles. ， Step (II) : A step of selectively heating a part of the thermally expandable base material to a temperature at which the thermally expandable particles expand or more, and selectively peeling off a part of the plurality of processing inspection objects. Hereinafter, the outline of the configuration of the adhesive sheet used in the method for thermally peeling a processing inspection object according to this embodiment will be described first, and then each step including steps (I) and (II) will be described. The details of the constituent materials and the like of the adhesive sheet will be described later.

[Configuration of Adhesive Sheet] 的 The adhesive sheet of this embodiment is not particularly limited as long as it has a non-adhesive thermally expandable base material and an adhesive layer containing a resin and thermally expandable particles. Figures 1 and 2 show the structure of the adhesive sheet according to this embodiment, and are sectional model views of the adhesive sheet.

As an adhesive sheet of this embodiment, as shown in FIG.1 (a), the adhesive sheet (single-sided adhesive sheet) 1a which has the adhesive layer (X1) 121 on the heat-expandable base material 11 is mentioned. Furthermore, the adhesive sheet of this embodiment may also be an adhesive sheet 1b as shown in FIG. 1 (b), and further includes a release material 131 on the adhesive surface of the adhesive layer (X1) 121.

The adhesive sheet of this embodiment may be a double-sided adhesive sheet 2a as shown in FIG. 2 (a), which is sandwiched between a thermally expandable substrate 11 via an adhesive layer (X1) 121 and an adhesive layer (X2) 122. Hold the composition. Moreover, as shown in FIG. 2 (b), the double-sided adhesive sheet 2b may further include a release material 131 on the adhesive surface of the adhesive layer (X1) 121, and an adhesive surface on the adhesive layer (X2) 122. The upper part further has a configuration of a release material 132.

Moreover, in the double-sided adhesive sheet 2b shown in FIG. 2 (b), the peeling force when peeling the release material 131 from the adhesive layer (X1) 121 and the peeling material 132 from the adhesive layer (X2) 122 When the peeling force at the time is the same, if the release materials of both sides are pulled and peeled to the outside, the adhesive layer will be split and torn along with the two release materials. (2) From the viewpoint of suppressing such a phenomenon, it is preferable to use two types of release materials designed so that the peeling forces of the two release materials 131 and 132 from the adhesive layer to be adhered to each other are different.

As another adhesive sheet, in the double-sided adhesive sheet 2a shown in FIG. 2 (a), the adhesive surface of one of the adhesive layer (X1) 121 and the adhesive layer (X2) 122 may be laminated. A release material that has been subjected to a release treatment on both sides has a double-sided adhesive sheet having a configuration in which it is wound into a roll shape.

Furthermore, in the adhesive sheet of this embodiment, the adhesive sheets 1a and 1b shown in FIG. 1 and the double-sided adhesive sheets 2a and 2b shown in FIG. 2 may be directly laminated with a thermally expandable substrate and The structure of the adhesive layer may be a structure having another layer between the thermally expandable substrate and the adhesive layer.

[Step (I)] In step (I), a plurality of processing inspections are attached to the adhesive surface of the adhesive layer (X1) of the non-adhesive thermally expandable substrate and the adhesive sheet of the adhesive layer (X1). In the step of the object, the non-adhesive heat-expandable substrate contains a resin and heat-expandable particles. The 薄片 adhesive sheet is the aforementioned adhesive sheet. For example, the single-sided adhesive sheet 1a shown in FIG. 1 and the double-sided adhesive sheet 2a shown in FIG. 2 can be used. FIG. 3 (a) is a schematic cross-sectional view illustrating step (I) of the method for thermally peeling a processing inspection object using the single-sided adhesive sheet 1a according to this embodiment, and FIG. 3 (b) is a schematic plan view. In addition, FIG. 4 (a) is a schematic cross-sectional view illustrating step (I) of the method for thermally peeling a processing inspection object using the double-sided adhesive sheet 2a in this embodiment, and FIG. 4 (b) is a schematic plan view.

As shown in FIGS. 3 (a) and 3 (b) and FIGS. 4 (a) and 4 (b), the adhesive sheets 1a and 2a are preferably fixed by a fixing means 60 and used. Thereby, during processing or peeling of the processing inspection object, it is possible to suppress processing defects or positional shifts of the processing inspection object caused by the movement of the adhesive sheet. Examples of the fixing means 60 include ring frame fixing, base fixing, and vacuum suction fixing.

Here, in the method for heating and peeling an object to be processed and inspected in this embodiment, for example, when a single-sided adhesive sheet 1a as shown in FIG. 1 is used, as shown in FIG. X1) 121 is used by sticking the frame member 20 to the adhesive surface 121a. Thereby, the single-sided adhesive sheet 1a is supported by the frame member 20, and the single-sided adhesive sheet 1a is maintained in a flat state. Therefore, the operability of the single-sided adhesive sheet 1a in steps (I) and (II) is improved. In addition, workability when placing and attaching an inspection object to a single-sided adhesive sheet 1a is also improved. When the single-sided adhesive sheet 1 a has a release material 131, the release material 131 is previously peeled. (2) The frame member 20 includes one or more openings 21 that pass through holes on the front and back surfaces of the frame member 20. The shape of the opening 21 is not particularly limited as long as it can accommodate the processing inspection objects 7 and 7a in the frame. The depth of the hole in the opening 21 is not particularly limited as long as it can accommodate the processing inspection objects 7 and 7a in the frame. Furthermore, from the viewpoint of further improving the support function of the frame member 20 with respect to the single-sided adhesive sheet 1 a, the frame member 20 preferably includes a plurality of openings 21. When the frame member 20 includes a plurality of openings 21, the shape of the openings 21 is preferably, for example, a grid. In addition, in the present embodiment, when "the plurality of processing inspection objects are attached", when the frame member 20 includes the plurality of opening portions 21, it means that the adhesive surface exposed from the plurality of opening portions 21 Each person is attached with one or more processing inspection objects. Alternatively, when the frame member 20 includes one opening 21, it means that a plurality of objects to be inspected for processing are attached to the adhesive surface exposed from the one opening 21. In addition, when the frame member 20 includes a plurality of openings 21, the position of the processing inspection object attached to the adhesive sheet can be grasped by the addresses of the plurality of openings 21, and it also has It is easy to control the advantages of the heating means or the picking means described later. The frame member 20 is preferably formed of a material having heat resistance. Examples of the material of the frame member 20 include metals such as copper, stainless steel, and 42 alloy; polyimide resin, polyacetal resin, polyimide resin, polycarbonate resin, modified polyphenylene ether resin, and Polybutylene terephthalate resins are resins called engineering plastics; glass epoxy resins and other composite materials.厚度 The thickness of the frame member 20 (thickness in the vertical direction with respect to the adhesive surface of the adhesive layer (X1)) may be appropriately determined in consideration of mechanical strength and operability, and is, for example, 100 μm to 3 mm.

In addition, in the method for heat-peeling an object to be processed and inspected in this embodiment, for example, when a double-sided adhesive sheet 2a shown in FIG. 2 is used, it is preferable to be as shown in FIG. 4 in the adhesive layer (X2). A hard support 14 is attached to the adhesive surface 122a and used. Thereby, the double-sided adhesive sheet 2a is supported by the hard support 14, and the double-sided adhesive sheet 2a is maintained in a flat state. Therefore, the operability of the double-sided adhesive sheet 2a in steps (I) and (II) is improved. Moreover, workability at the time of placing and sticking an adherend on the double-sided adhesive sheet 2a is also improved. When the double-sided adhesive sheet 2 a has a release material 132, the release material 132 is previously peeled. From the viewpoint of achieving the above-mentioned object, the hard support 14 is preferably the entire surface of the adhesive surface 122a adhered to the adhesive layer (X2) 122. Therefore, the rigid support 14 is preferably plate-shaped. The area of the surface of the hard support 14 attached to the adhesive surface 122 a of the adhesive layer (X2) 122 is preferably equal to or greater than the area of the adhesive surface 122 a of the adhesive layer (X2) 122. The material of the hard support 14 may be appropriately determined in consideration of mechanical strength and heat resistance. Examples include metal materials such as SUS; non-metallic inorganic materials such as glass and silicon wafers; polyimide and polyimide Resin materials such as arsenim; composite materials such as glass epoxy resin; among these, SUS, glass, and silicon wafers are preferred. The thickness of the hard support 14 may be appropriately determined in consideration of mechanical strength, operability, and the like, and is, for example, 100 μm to 50 mm.

The plurality of processing inspection objects 7, 7a are not particularly limited as long as they are temporarily attached to the adhesive sheets 1a, 2a, and are necessary for at least one of processing and inspection. An object to be processed and inspected is, for example, a substrate such as a silicon wafer that has been singulated (single-piece). The object to be processed and inspected may be a laminated body in which two or more members are laminated. The two or more component systems may be the same type or different types. The processing system to be processed and inspected is not particularly limited, and examples thereof include wiring formation, resin encapsulation described later, and the like.的 There is no particular limitation on the inspection performed on the processing inspection object, and examples include defect inspection using an optical microscope or laser (for example, dust inspection, surface flaw inspection, wiring pattern inspection, etc.), visual inspection of the surface, and the like.

[Step (II)] In step (II), a part of the thermally expandable substrate is heated to a temperature at which the thermally expandable particles expand or more, and a part of the plurality of processing inspection objects is selectively peeled. The plurality of processing inspection objects are selectively peeled, for example, after at least one of the processing and inspection is performed. FIG. 5 is a schematic cross-sectional view illustrating step (II) of the method for heating and peeling a processing inspection object using the single-sided adhesive sheet 1a of this embodiment, and FIG. 5 (a) is a diagram illustrating the processing inspection object 7a to be peeled off FIG. 5 (b) shows the state before the peeling of the processing inspection object 7a to be peeled off, and the state is recovered. 6 is a schematic cross-sectional view illustrating step (II) of the method for heating and peeling a process inspection object using the double-sided adhesive sheet 2a of this embodiment, and FIG. 6 (a) is a process inspection object to be peeled off. FIG. 6 (b) shows a state before the peeling of 7a, and FIG. 6 (b) shows a state where the processing inspection object 7a to be peeled is peeled off and recovered.

Here, in the method for heat-peeling an object to be processed and inspected in this embodiment, a single-sided adhesive sheet 1a is used, and a frame member 20 is attached to the adhesive surface 121a of the adhesive layer (X1) 121 of the single-sided adhesive sheet 1a. During use, the entire surface of the heat-expandable substrate 11 on the side opposite to the side where the adhesive layer (X1) 121 is laminated (hereinafter, also simply referred to as the "back surface") can be fixed by a fixture or the like. In a fixed state, step (II) is performed. By fixing the back surface with a fixing jig or the like, it is possible to suppress formation of unevenness on the back surface side due to expansion of the thermally expandable particles. Thereby, unevenness can be efficiently formed on the adhesive surface 121a side of the adhesive layer (X1) 121. Therefore, a desired object to be inspected for processing can be easily peeled from the single-sided adhesive sheet 1a. For example, as the fixing jig, a suction table having a plurality of suction holes and a pressure reducing mechanism such as a vacuum pump can be used. The pressure reducing mechanism can attract the adhesive sheet from the plurality of suction holes, and the adhesive sheet can be fixed to the suction surface.

Furthermore, in the method for heat-peeling an object to be processed and inspected in this embodiment, as shown in FIG. 4 (b), a double-sided adhesive sheet 2a is used, and an adhesive layer (X2) 122 of the double-sided adhesive sheet 2a is used. When the hard support 14 is attached to the adhesive surface 122a and used, the formation of unevenness in the adhesive surface 122a on the adhesive layer (X2) 122 side can be suppressed when the thermally expandable particles are expanded. Thereby, unevenness can be efficiently formed on the adhesive surface 121a side of the adhesive layer (X1) 121. Therefore, a desired processing inspection object can be easily peeled from the double-sided adhesive sheet 2a. In addition, such an effect can also be achieved when a hard support is used after the rigid support is adhered to the back surface of the single-sided adhesive sheet 1a.

The heating method in step (II) is not particularly limited as long as it can be heated to a temperature at which the thermally expandable particles in the thermally expandable substrate 11 expand, and for example, an electric heater; dielectric heating; magnetic heating can be suitably used. ; Heating of electromagnetic waves such as infrared rays, such as near-infrared, mid-infrared, and far-infrared. The heating method may be any of a direct heating method and an indirect heating method.

In step (II), the heating means 80 for heating the heat-expandable substrate 11 of the adhesive sheet includes a heating section 81. The material of the heating portion 81 is appropriately selected according to the heating method. For example, when an electric heating heater is used as the heating method, the heating section 81 is composed of a material having a high thermal conductivity such as a metal material, and a heat insulating material such as an artificial mineral fiber. In addition, from the viewpoint of more selectively and efficiently heating the region to be heated, an elastic body such as rubber (thermally conductive elastomer) may be provided at the tip of the heating portion, and the elastic body may be pressed to the region to be heated. While heating.

The shape or size of the heating portion 81 in the heating means 80 can be appropriately designed in accordance with the shape of the processing inspection object 7a to be peeled. When the application site is heated by using the heating means 80 having a heating part 81 that matches the shape of the inspection object 7a to be peeled, the thermal expansion substrate 11 thermally expands in a region corresponding to the application site. Sex particles expand. As a result, the contact area of the adhesive surface 121a of the adhesive layer (X1) 121 with the processing inspection object 7a to be peeled off in the area corresponding to the attachment portion is reduced, and the adhesive force is lost. Therefore, the processing inspection object 7a to be peeled can be selectively peeled off, and for example, it can be easily recovered by a pickup means such as the suction nozzle 15. Furthermore, from the viewpoint of selectively peeling a processing inspection object attached to a desired position on the adhesive sheet, the heating means 80 is preferably in the X-axis direction and Y-axis direction of the XY plane of the adhesive sheet. Can move. The picking means such as the suction nozzle 15 is also preferably one capable of moving in the X-axis direction and the Y-axis direction of the XY plane of the adhesive sheet. In addition, the heating means 80 and the pickup means such as the suction nozzle 15 can be moved in the Z-axis direction.所谓 The "XY plane" in this specification means a plane orthogonal to the lamination direction (thickness direction) of the adhesive sheet. The X-axis and Y-axis are orthogonal to each other and become axes in the XY plane. The Z axis is orthogonal to the X axis and the Y axis, and is an axis parallel to the lamination direction (thickness direction) of the adhesive sheet. Furthermore, a plurality of heating means and picking means may be provided. In this case, for example, among n (n is an integer of 3 or more) processing inspection objects, m (m is an integer satisfying 1 <m <n) processing and inspection objects may be heated and peeled off at the same time and recovered. In addition, the heating means and the picking means may have a size capable of simultaneously heating and peeling two or more adjacent processing inspection objects. In this case, a plurality of objects to be inspected for processing and inspection may be simultaneously peeled and recovered. In addition, a plurality of heating means and pick-up means capable of simultaneously heating and peeling off two or more adjacent processing inspection objects can be provided.

The heating temperature of the heating means 80 is a temperature of "the temperature at which the thermally expandable particles expand". The temperature of "the temperature at which the thermally expandable particles expand" is "the temperature at which the expansion coefficient of the thermal expansion particles (t) or more", preferably "the expansion start temperature (t) + 10 ° C" or more "the expansion start temperature (t) + 60 ° C "or less, more preferably" Expansion start temperature (t) + 15 ° C "or more, and" Expansion start temperature (t) + 40 ° C "or less. Specifically, the thermally expandable particles can be expanded by heating to a range of 120 to 250 ° C, for example.

The heating time of the heating means 80 is set so that only the processing inspection object 7a to be peeled off can be peeled off, and the attachment areas of the other processing inspection objects 7 are not heated to a temperature "above the temperature at which the thermally expandable particles expand". .

Here, the heating means 80 may be provided on the processing inspection object side, or may be provided on the side opposite to the processing inspection object side. In other words, the heating means 80 may be provided on the side of the laminated adhesive layer (X1) 121 of the heat-expandable substrate 11 or on the side of the heat-expandable substrate 11 and the laminated adhesive layer (X1) 121. The opposite side. Alternatively, it may be provided on both sides to shorten the heating time. Here, in one aspect of the present invention, it is preferable that the heating means 80 is provided on the side opposite to the object to be processed and inspected. When the adhesive sheet used in the present invention contains thermally expandable particles in a base material, the thermally expandable particle system is compared with the case where thermally expandable particles are included in an adhesive layer (adhesive layer of an object to be inspected by an attacher). It exists closer to the heating means 80. Therefore, the heat-expandable particles can be easily heated, and the heating time can be shortened. Furthermore, the farther the distance between the heating system 80 from the heating means 80 and the heating means 80 is, the easier it is to diffuse in a direction that is horizontal to the direction in which the heat advances. Therefore, when the heating means 80 is provided on the side opposite to the object to be processed and inspected, if the adhesive layer (adhesive layer of the object to be inspected by the attacher) includes thermally expandable particles, the adhesive layer is heated. In a wider range than the desired area, the thermally expandable particles swell, and the object to be inspected for processing attached to the area where peeling is not desired may be peeled off. On the other hand, the adhesive sheet used in the present invention expands the thermally expandable particles in the thermally expandable substrate closer to the heating means 80 than the adhesive layer, so that the object to be inspected is peeled off from the heating means 80. The thermal system is irradiated in a state where diffusion is suppressed in the adhesive layer (X1) than in the thermally expandable substrate. Therefore, it is easy to selectively peel only a desired object to be inspected for processing by selectively heating only a desired area.

In addition, when the heating means 80 is provided on the processing inspection object side, if the processing inspection object is a substance having low thermal conductivity, heat is not spread to the lower layer of the processing inspection object, and the thermally expandable particles are not expanded, and the processing inspection object is processed. Peeling of objects becomes difficult. This point is as described above. When the heating means 80 is provided on the side opposite to the processing inspection object side, it does not depend on the type of the processing inspection object, and can be easily peeled off even for all the processing inspection objects. Therefore, since the heating means 80 is provided on the processing inspection object side, it does not depend on the type of the processing inspection object, and also has the advantage of being able to selectively peel only the desired processing inspection object.

In addition, when the back surface of the single-sided adhesive sheet is fixed with a fixing jig, or when a hard support is attached to the adhesive layer (X2) of the double-sided adhesive sheet and used, it is preferably opposite to the object to be processed and inspected. A heating means 80 is installed on the side, and at the same time, in the fixing jig and the rigid support, a material having a high thermal conductivity such as a metal material is used to constitute an area corresponding to the attachment area of the processing inspection object, and a material having a low thermal conductivity such as a heat insulation material is used. Make up other areas. Thereby, it is possible to selectively heat a desired area by the heating means 80, and it is easy to selectively peel only a desired processing inspection object.

In addition, from the viewpoint of peeling the inspection object more quickly, the entire adhesive sheet may be heated in advance to a temperature at which the thermally expandable particles do not swell, and then step (II) may be performed. In this way, since the entire adhesive sheet is first heated to a temperature at which the thermally expandable particles do not swell, when heating is performed to selectively peel the processing inspection object, the desired area can quickly reach the temperature at which the thermally expandable particles expand. Above the temperature. Therefore, the selective peeling of the processing inspection object can be performed more quickly.

The adhesive sheet used in the heat-peeling method for a process inspection object according to this embodiment is not included in the adhesive layer of the applicator inspection object, but includes a thermally expandable substrate in a thermally expandable substrate. (2) When thermally expansive particles are contained in the adhesive of the inspection object, the residue from the thermally expansive particles adheres to the surface of the processing inspection object, and the cleanliness of the surface of the inspection object cannot be processed. In addition, when the thermally expandable particles are foamed or expanded by heating, the adhesive layer may be greatly deformed, and there may be a concern that residues may occur on the surface of the object to be processed and inspected after thermal peeling. In contrast, in the adhesive sheet of this embodiment, since the thermally expandable particles are contained in the thermally expandable substrate, the processing inspection object attached to the adhesive surface of the adhesive layer does not directly contact the thermally expandable particles. . Therefore, those who suppress the residue from the thermally expandable particles and a part of the adhesive layer that is greatly deformed from adhering to the surface of the processing inspection object can ensure the cleanliness of the surface of the processing inspection object after heat peeling and the suppression of residues. It is possible to selectively heat and peel a desired portion among a plurality of processing inspection objects attached to the adhesive sheet. In the following, the thermal peeling method of the object to be processed and inspected in this embodiment is described in detail about the storage modulus and thickness of the thermally expandable substrate, the storage shear modulus and thickness of the adhesive layer (X1), and the thermally expandable substrate. A preferable range of the relationship between the thickness of the SiO 2 and the thickness of the adhesive layer (X1).

(Storage Modulus and Thickness of Thermally Expandable Base Material) The thermally expandable base material of the adhesive sheet of this embodiment is preferably a storage modulus E '(23) at 23 ° C of 1.0 × 10 ⁶ Pa or more, more preferably 5.0 × 10 ⁶ to 5.0 × 10 ¹² Pa, particularly preferably 1.0 × 10 ⁷ to 1.0 × 10 ¹² Pa, even more preferably 5.0 × 10 ⁷ to 1.0 × 10 ¹¹ Pa, and particularly preferably 1.0 × 10 ⁸ to 1.0 × 10 ¹⁰ Pa. Hereinafter, the above range of the storage modulus E '(23) at 23 ° C is referred to as a requirement (1). The use of a thermally expandable substrate that satisfies the above-mentioned requirement (1) makes it possible to suppress the positional deviation of the processing inspection object when the processing inspection object is placed and attached to the adhesive sheet. In addition, it is possible to suppress the process inspection object from being stuck in the adhesive layer (X1) when the process inspection object is placed and attached to the adhesive sheet, and good peelability can be ensured. For example, a well-known device such as a flip-chip wafer bonding machine or a die bonding machine may be used for placing the processing inspection object on the adhesive layer (X1) of the adhesive sheet. When using such a device, when an object to be inspected for processing is placed on the adhesive layer (X1) of the adhesive sheet, a pressing force is applied to the object to be inspected for processing in the thickness direction of the adhesive sheet. Therefore, there is a possibility that the object to be inspected for processing may be excessively caught in the thickness direction of the adhesive layer (X1). Moreover, when such a device is used to place the processing inspection object on the adhesive sheet, a force is also applied to move the processing inspection object in the horizontal direction of the adhesive sheet, so there is also a processing inspection object on the adhesive layer. There may be a position shift in the horizontal direction of. In addition, due to the weight of the processing inspection object itself, there is a possibility that the processing inspection object may excessively fall into the thickness direction side of the adhesive layer (X1). These problems can be solved by using a thermally expandable substrate that satisfies the above-mentioned requirement (1). In addition, in this specification, the storage modulus E 'of a thermally expandable base material at a specific temperature means the value measured by the method described in an Example.

In addition, the thermally expansible base material of the adhesive sheet of this embodiment has a storage modulus E '(100) at 100 ° C of preferably 2.0 × 10 ⁵ Pa or more, more preferably 4.0 × 10 ⁵ Pa or more, and particularly preferably It is 6.0 × 10 ⁵ Pa or more, particularly preferably 8.0 × 10 ⁵ Pa or more, and particularly preferably 1.0 × 10 ⁶ Pa or more. The storage modulus E '(100) at 100 ° C is preferably 1.0 × 10 ¹² Pa or less, more preferably 1.0 × 10 ¹¹ Pa or less, even more preferably 1.0 × 10 ¹⁰ Pa or less, and even more preferably 1.0 ×. 10 ⁹ Pa or less. Hereinafter, the above range of the storage modulus E '(100) at 100 ° C is referred to as a requirement (2). Since a thermally expandable substrate that satisfies the above-mentioned requirement (2) is used, it is possible to suppress the positional shift of the adhesive sheet during a temperature rise process in which a part of the adhesive sheet is heated to a temperature at which the thermally expandable particles expand. In addition, during a temperature increase process in which a part of the adhesive sheet is heated to a temperature at which the thermally expandable particles expand, the process inspection object can be prevented from sinking into the adhesive layer (X1), and good peelability can be ensured. Generally, the thermally expandable adhesive layer included in the adhesive sheet described in Patent Document 1 contains an adhesive resin, and as the temperature increases, the degree of decrease in storage modulus E ′ tends to be very large. Here, if the degree of decrease in the storage modulus E ′ of the thermally expandable adhesive layer becomes very large, the thermally expandable particles and the adhesive resin contained in the thermally expandable adhesive layer will easily flow, and the thermally expandable adhesive will accompany this. The adhesive surface of the layer is easily deformed. As a result, during a temperature increase process in which a part of the adhesive sheet is heated to a temperature at which the thermally expandable particles expand, the position of the object to be inspected for processing is liable to shift. In addition, the object to be inspected for processing may sink into the adhesive sheet side, which may cause the problem that the object to be inspected for processing becomes difficult to peel off. These problems can be solved by using a thermally expandable substrate that satisfies the above-mentioned requirement (2).

The thermally expansible base material of the adhesive sheet of this embodiment has a storage modulus E '(t) at t ° C of preferably 1.0 × 10 ⁷ Pa or less, more preferably 9.0 × 10 ⁶ Pa or less, and particularly preferably It is 8.0 × 10 ⁶ Pa or less, particularly preferably 6.0 × 10 ⁶ Pa or less, and particularly preferably 4.0 × 10 ⁶ Pa or less. In addition, "t" is the expansion start temperature of a thermal expansion particle, and is 120-250 degreeC here. Hereinafter, the above range of the storage modulus E '(t) at t ° C is referred to as a requirement (3). Since it has a thermally expandable base material that satisfies the requirement (3), the thermally expandable base material is easily deformed in accordance with the volume expansion of the thermally expandable particles at a temperature at which the thermally expandable particles are expanded, and the adhesive layer (X1) becomes easy. Thereby, the peeling property of the process inspection object from the adhesive sheet can be made more excellent. In addition, from the viewpoint of suppressing the flow of the expanded thermally expandable particles, improving the shape retention of the unevenness formed on the adhesive surface of the adhesive layer (X1), and improving the peelability, the storage pattern of the thermally expandable substrate The number E '(t) is preferably 1.0 × 10 ³ Pa or more, more preferably 1.0 × 10 ⁴ Pa or more, and even more preferably 1.0 × 10 ⁵ Pa or more.

The thickness of the thermally expandable base material of the adhesive sheet of this embodiment is preferably 10 to 1,000 μm, more preferably 20 to 500 μm, even more preferably 25 to 400 μm, and even more preferably 30 to 300 μm. In addition, in this specification, the thickness of a thermally expandable base material means the value measured by the method as described in an Example.

(Storage Shear Modulus and Thickness of Adhesive Layer (X1)) In the adhesive sheet of this embodiment, the storage shear modulus G '(23) of the adhesive layer (X1) at 23 ° C is preferably 1.0. × 10 ⁴ to 1.0 × 10 ⁸ Pa, more preferably 5.0 × 10 ⁴ to 5.0 × 10 ⁷ Pa, and even more preferably 1.0 × 10 ⁵ to 1.0 × 10 ⁷ Pa. If the storage shear modulus G '(23) of the adhesive layer (X1) is 1.0 × 10 ⁴ Pa or more, the position of the processing inspection object can be prevented, and the processing inspection object can also be prevented from moving to the adhesive layer. (X1). On the other hand, if the storage shear modulus G '(23) of the adhesive layer (X1) is 1.0 × 10 ⁸ Pa or less, the unevenness caused by the expanded thermally expandable particles is likely to be formed on the adhesive surface. It is easy to peel off the inspection object. In addition, in this specification, the storage shear modulus G '(23) of the adhesive layer (X1) means the value measured by the method described in an Example.

In addition, the thickness of the adhesive layer (X1), from the viewpoint of exhibiting excellent adhesion, and the viewpoint that it is easy to form irregularities on the surface of the adhesive layer by the expansion of the thermally expandable particles in the thermally expandable substrate due to heat treatment. From the viewpoint, it is preferably 1 to 60 μm, more preferably 2 to 50 μm, even more preferably 3 to 40 μm, and even more preferably 5 to 30 μm. The thermally expandable adhesive layer included in the adhesive sheet described in Patent Document 1 must have a certain thickness in order to sufficiently contain the thermally expandable particles. Therefore, there is a possibility that the position of the processing inspection object is shifted, or the processing inspection object may fall into the adhesive sheet side. In contrast, the adhesive sheet of this embodiment is composed of thermal expansion particles contained in a non-adhesive base material having a high elastic modulus, and the thickness, adhesive force, and adhesiveness of the adhesive layer (X1) on which the semiconductor wafer is placed are adjusted. The degree of freedom in controlling the viscoelastic modulus and the like is increased. Thereby, the occurrence of the positional deviation of the semiconductor wafer can be suppressed, and at the same time, the semiconductor wafer can be prevented from sinking into the adhesive sheet.

(Relationship between the thickness of the thermally expandable substrate and the thickness of the adhesive layer (X1)) In the adhesive sheet of this embodiment, the thickness of the thermally expandable substrate at 23 ° C from the viewpoint of exhibiting better peelability. The ratio to the thickness of the adhesive layer (thermally expandable substrate / adhesive layer) is preferably 0.2 or more, more preferably 0.5 or more, particularly preferably 1.0 or more, and even more preferably 5.0 or more. It is preferably 1,000 or less, more preferably 200 or less, particularly preferably 60 or less, and even more preferably 30 or less.

(Steps (I-1) to (I-2)) In the method for heat-peeling a processing inspection object according to this embodiment, a plurality of processing inspection objects may be attached to a processing inspection object before being singulated. It is temporarily fixed on an adhesive sheet, and cut into pieces to give a piece. That is, step (I) may have the following steps (I-1) to (I-2), (1) Step (I-1): attaching a sheet to the adhesive surface of the adhesive layer (X1) of the aforementioned adhesive sheet The step of processing and inspecting the object before conversion, (1) Step (I-2): the step of performing the individualization of the object of the inspection and processing before the individualization to be adhered to the aforementioned adhesive surface, followed by step (I-1) Here, the object of processing and inspection before the individualization of the adhered sheet is, for example, a silicon wafer or an FPC part. In addition, in step (I-2), the method of singulating the processing inspection object before singulation is not particularly limited, and for example, it is performed by a cutting means such as a dicing saw. Alternatively, the processing inspection object having grooves formed on the front side of the processing inspection object along the predetermined division line may be attached so that the front side contacts the adhesive surface of the adhesive sheet, and the process inspection object is attached from the back side of the processing inspection object to At least until the groove is reached, a thinning process such as grinding of the processing inspection object is performed, and the processing inspection object is singulated by a so-called "first cutting method". In addition, it is also possible to use invisible cutting (registered trademark) to form a modified area inside the processing inspection object, and then attach it so that the front side of the processing inspection object contacts the adhesive surface of the adhesive sheet, from the back of the processing inspection object. It performs grinding, thins the processing inspection object, and applies an external force, such as pressure, to the processing inspection object into pieces. Furthermore, the adhesive sheet to which the processed inspection objects are divided into pieces can be expanded to arbitrarily increase the interval between the processed inspection objects. In addition, it is possible to perform the singulation and expansion processing of the inspection target at the same time. In addition, the processing inspection object that has been sliced through steps (I-1) to (I-2) or the processing inspection object that is further expanded may be directly supplied to step (II), or may be further processed. After at least one of the processing and inspection is performed, it is supplied to step (II).

(Steps (I-A1) to (I-A3), Steps (I-B1) to (I-B3)) In the method of heating and peeling the processing inspection object of this embodiment, a plurality of processing inspection objects are preferred In order to form a package in which a plurality of semiconductor wafers obtained in a semiconductor package manufacturing process are packaged with a packaging material, the packages are singulated in units of semiconductor wafers. That is, in the method for heating and peeling an object to be processed and inspected in this embodiment, it is preferable to continuously process the packaging of a plurality of semiconductor wafers through a packaging material on the same adhesive sheet, and the unit of the package is a semiconductor wafer unit. And the selective heating and peeling of the package formed by the semiconductor wafer unit.

In recent years, the miniaturization, weight reduction, and high performance of electronic devices have progressed, and along with this, semiconductor devices mounted on electronic devices have also been required to be reduced in size, thickness, and density. As a semiconductor package capable of responding to such requirements, FOWLP (Fan out Wafer Level Package) or FOPLP (Fan out Panel Level Package) have attracted attention. In the manufacturing process of FOWLP and FOPLP, the semiconductor wafer is covered with a packaging material so as to become a larger area than the wafer size, and a package of the semiconductor wafer is formed (hereinafter, also referred to as "package" only), not only the semiconductor wafer Circuit surface, and in the surface area of the package body, a redistribution layer and an external electrode are also formed.

However, the manufacturing process of semiconductor packages typified by FOWLP and FOPLP includes the steps of placing a plurality of semiconductor wafers on a temporarily fixed adhesive sheet (hereinafter, also referred to as a "temporarily fixed sheet"). And a coating step of covering with a packaging material that imparts fluidity due to heating, and a hardening step of thermally curing the packaging material. After these steps, a package is formed. For the temporary fixing sheet used in the manufacture of a semiconductor package, it is required that the position of the semiconductor wafer does not shift between the coating step and the hardening step (hereinafter, these are also referred to as "packaging steps"), and Adhesiveness to the extent that the packaging material does not enter the bonding interface between the semiconductor wafer and the temporary fixing sheet. In addition, after the encapsulation step, a peelability that can be easily removed without residual adhesive is required. That is, the temporarily fixed sheet used in the manufacture of a semiconductor package requires both the adhesiveness at the time of use (at the time of temporary fixation) and the peelability after use.

Here, for example, in the manufacturing processes of FOWLP and FOPLP, after the packaging step, a separation step is generally performed after the package is peeled off from the temporarily fixed sheet, and a rewiring layer is formed on the surface of the semiconductor wafer side of the package. A wiring layer forming step and a cutting step of cutting the package in which the rewiring layer has been formed into individual semiconductor wafer units, and manufacturing the FOWLP and FOPLP. However, in the manufacturing process of FOWLP and FOPLP, a modification example of the above general steps is also considered. For example, it is also considered that after the packaging step, the package is not peeled off from the temporarily fixing sheet to be separated, and is divided into individual semiconductor wafers to form individual pieces (hereinafter, also referred to as "package individual piece forming step"). A part of the packaged pieces is selectively peeled and separated from the temporarily fixing sheet (Modification 1). In the modification 1, the redistribution layer forming step is performed after the packaging step, but before the step of singulating the package body (modification 1a). The redistribution layer forming step is performed after, for example, the step of forming the package into pieces, and then selectively peeling the piece of package from the sheet for temporary fixing (modified example 1b). Alternatively, the redistribution layer forming step is performed after, for example, selectively peeling the individual package from the sheet for temporary fixation (Modification 1c). According to these modified examples 1a to 1c, only the package containing the required semiconductor wafer can be selectively peeled from the sheet for temporary fixing among the individual packaged packages and recovered. In addition, only the package containing the required semiconductor wafer may be left in a state of being attached to the temporarily fixed sheet, and other packaging systems may be peeled off and recovered. For example, when a packaging system including a plurality of semiconductor wafers with different wiring patterns is mixed, only a package containing a semiconductor wafer with a specific wiring pattern can be selectively removed from the adhesive sheet, or left on the adhesive sheet. on. Further, in the case of the modified examples 1a and 1b, in the step of forming the redistribution layer, it is possible to selectively remove a person who has a problem in the wiring from the adhesive sheet, or to leave it on the adhesive sheet. And these are not only applicable to the process of FOWLP and FOPLP, but also applicable to other semiconductor packaging processes.

Therefore, it is also considered to use the adhesive sheet described in Patent Document 1 as a temporary fixing sheet in the packaging step and the individualization step of the package in the manufacturing process of the semiconductor package. However, according to the review by the present inventors, it was found that when the adhesive sheet described in Patent Document 1 is used as a temporary fixing sheet, the elastic modulus of the thermally expandable adhesive layer is reduced due to the heating in the encapsulation step, and the The semiconductor wafer is stuck on the side of the adhesive sheet. It was also found that the positional displacement of the semiconductor wafer occurred in the mounting step and the packaging step. Because of this, in the surface on the semiconductor wafer side of the package, a step occurs between the surface of the semiconductor wafer and the surface of the packaging material, resulting in poor flatness, or a result that the position accuracy of the semiconductor wafer is reduced. Such a decrease in the flatness of the surface of the semiconductor wafer side of the package and a decrease in the positional accuracy of the semiconductor wafer may be related to a defect in a later step. For example, when a redistribution layer is formed on the surface of the semiconductor wafer side of the package, a decrease in redistribution accuracy may occur. Therefore, it is desirable to suppress a decrease in the flatness of the surface of the semiconductor wafer side of the package and a decrease in the positional accuracy of the semiconductor wafer. In addition, when the package is peeled from the adhesive sheet, the thermally expandable adhesive layer is also expanded by heating. Because the semiconductor wafer is trapped on the adhesive sheet side, if there is no external force to a certain degree, the package is divided into pieces. Peeling becomes difficult. In addition, as described above, when the adhesive sheet described in Patent Document 1 is used as a temporary fixing sheet, the adhesive layer contains thermally expandable particles, and contamination is caused by residues from the thermally expandable particles and / or the adhesive layer. Anxiety on the surface of the processing inspection object after heat peeling. In addition, the uneven shape on the surface of the adhesive layer formed of the thermally expandable particles is transferred to the surface on the semiconductor wafer side of the package, and there is a concern that the smoothness is reduced.

For these problems, by using the same adhesive sheet having a heat-expandable substrate containing heat-expandable particles, the semiconductor wafer packaging by the packaging material, the singulation of the package, and the singulated package are continuously processed. The selective heating and peeling can suppress the occurrence of the positional deviation of the semiconductor wafer, and at the same time ensure the flatness of the surface of the semiconductor wafer side of the package, which can make the rewiring accuracy and the peelability of the package from the adhesive sheet good. In addition, an extremely excellent effect of selectively heating and peeling the individual packages into pieces is achieved. Hereinafter, steps (I-A1) to (I-A3) and steps (I-B1) to (I-B3) in a state where the individualized package is attached to the adhesive sheet will be described in detail.

(Steps (I-A1) to (I-A3)) 时 When a single-piece package is attached to a double-sided adhesive sheet, step (I) has the following steps (I-A1) to (I-A3) (1) Step (I-A1): a step of placing a plurality of semiconductor wafers on the adhesive surface of the adhesive layer (X1) while setting a gap between the semiconductor wafers adjacent to the semiconductor wafers, and (1-A2): A step of covering the plurality of semiconductor wafers and the adhesive surfaces of the peripheral portions of the plurality of semiconductor wafers with a packaging material to harden the packaging material to obtain a package in which the plurality of semiconductor wafers are packaged in a hardened packaging material; I-A3): a step of singulating the package into individual semiconductor wafer units. Hereinafter, each step will be described while referring to the drawings.

In steps (I-A1) to (I-A3), as shown in FIG. 7 (a), a double-sided adhesive sheet 2a having a hard support 14 attached to the adhesive surface of the adhesive layer (X2) is used. Thereby, the double-sided adhesive sheet is supported by the rigid support, and is kept flat. Therefore, a package excellent in flatness can be obtained. In addition, the double-sided adhesive sheet is also excellent in operability, and a semiconductor wafer can be easily placed on the double-sided adhesive sheet. The structure, material, and thickness of the rigid support are as described above.

FIG. 7 (b) is a cross-sectional view illustrating a step of placing a gap between adjacent semiconductor wafers CP on the adhesive surface 121a of the adhesive layer (X1) 121 and simultaneously placing a plurality of semiconductor wafers CP (I- A1). Furthermore, when the double-sided adhesive sheet 2a has the release material 131, the release material 131 is peeled beforehand. Semiconductor wafer CP system can be used by a known person. The semiconductor wafer CP is formed on the circuit surface W1 of an integrated circuit composed of circuit elements such as a transistor, a resistor, and a capacitor. In addition, the semiconductor wafer CP is not limited to a single-layer structure, and can also be used as a laminated body in which two or more semiconductor wafers are laminated to manufacture a multi-stage laminated package of a wafer. The semiconductor wafer CP is mounted, for example, such that the circuit surface W1 is covered with the adhesive surface 121 a. For mounting the semiconductor wafer CP, a well-known device such as a flip-chip wafer bonding machine or a die bonding machine can be used. Here, the plurality of semiconductor wafers CP are preferably arranged neatly at a certain interval, and are placed on the adhesive surface 121a of the adhesive layer (X1) 121. The plurality of semiconductor wafers CP are more preferably separated by a certain distance. The matrix-like state in which a plurality of rows and a plurality of columns are neatly arranged at regular intervals is placed on the adhesive surface 121a. The interval between the semiconductor wafers CP can be appropriately determined according to the intended package form and the like.

7 (c) and 7 (d) are cross-sectional views illustrating that a plurality of semiconductor wafers CP and a peripheral surface of the plurality of semiconductor wafers CP are covered with a sealing material 40, and the sealing material 40 is hardened to obtain a plurality of Step (I-A2) of the package 50 in which the semiconductor wafer CP is sealed in a hardened sealing material 41. In addition, in the following, the step of covering the plurality of semiconductor wafers CP and the adhesive surface 30 of the peripheral portion of the plurality of semiconductor wafers CP with the packaging material 40 may be referred to as a "coating step", and the packaging material 40 may be hardened. The step of obtaining the package 50 in which the semiconductor wafer CP is encapsulated in the hardened sealing material 41 is referred to as a "hardening step".

As shown in FIG. 7 (c), in the coating step, first, the sealing surface 40 of the plurality of semiconductor wafers CP and the peripheral surface of the plurality of semiconductor wafers CP is covered with a sealing material 40. The packaging material 40 is filled in the gap between the semiconductor wafers CP while covering the entire exposed surface of the plurality of semiconductor wafers CP.

The packaging material 40 has a function of protecting a plurality of semiconductor wafers CP and elements accompanying them, and preventing an external environment. As the packaging material 40, there is no particular limitation, and any one of the users who have been conventionally used as a semiconductor packaging material can be appropriately selected and used.封装 From the viewpoints of mechanical strength, heat resistance, insulation, and the like, the sealing material 40 is a material having a curability, and examples thereof include a thermosetting resin composition, an energy ray curable resin composition, and the like. Hereinafter, in this embodiment, a case where the sealing material 40 is a thermosetting resin composition will be described.

Examples of the thermosetting resin contained in the thermosetting resin composition of the sealing material 40 include epoxy resins, phenol resins, cyanate resins, and the like, but they include mechanical strength, heat resistance, insulation properties, and moldability. From a viewpoint, an epoxy resin is preferable. The thermosetting resin composition may contain, in addition to the thermosetting resin, a hardener such as a phenol resin hardener, an amine hardener, a hardening accelerator, an inorganic filler such as silica, and elasticity, if necessary. Additives. The encapsulation material 40 is solid at room temperature, and may be liquid. In addition, the form of the solid sealing material 40 at room temperature is not particularly limited, and may be, for example, granular, flake, or the like.

As a method of covering the plurality of semiconductor wafers CP, the peripheral portions of the plurality of semiconductor wafers CP, and the adhesive surface 30 of the gap with the packaging material 40, any method suitable for the semiconductor packaging step in the past may be appropriately selected. The method can be applied, for example, a roll lamination method, a vacuum pressure method, a vacuum lamination method, a spin coating method, a die coating method, a transfer molding method, and a compression molding method can be applied. In these methods, in order to improve the filling property of the sealing material 40, the sealing material 40 is heated during coating to provide fluidity.

The encapsulation step is performed under a temperature condition that does not reach the expansion start temperature (t) of the thermally expandable particles.

As shown in FIG. 7 (d), after the coating step is performed, the packaging material 40 is hardened to obtain a package 50 in which a plurality of semiconductor wafers CP are packaged in the hardened packaging material 41. In addition, the coating treatment and thermal curing treatment of the packaging material 40 can be performed separately. However, when the packaging material 40 is heated during the coating treatment, the packaging material 40 can be directly hardened by the heating, and the coating treatment and thermal treatment can be performed at the same time. Hardened. Here, as described above, the double-sided adhesive sheet 2a used in the present embodiment has a heat-expandable substrate 11 containing heat-expandable particles. In step (II), the heat-expandable particles are expanded to reduce the adhesive layer. The contact area between the adhesive surface 121a of (X1) 121 and the package 50 reduces the adhesive force, and the package 50 is peeled from the double-sided adhesive sheet 2a to separate it. Therefore, in the coating step and the hardening step, it is preferable to appropriately select conditions under which the thermally expandable particles do not swell, and cover and harden the sealing material 40. For example, the heating conditions (heating temperature and heating time) in the coating step and the hardening step are preferably heating conditions in which the increase rate of the thickness of the double-sided adhesive sheet 2a due to the expansion of the thermally expandable particles is 10% or less, and more preferably The heating condition is the heating condition in which the aforementioned increase rate is 5% or less, and the heating condition in which the aforementioned increase rate is 0% (that is, the heating condition in which the thermally expandable particles do not expand) is particularly preferred. In addition, the increase rate of the thickness of the double-sided adhesive sheet 2a can be measured under specific conditions using a constant pressure thickness measuring device (manufactured by TECLOCK, product name "PG-02") in accordance with JIS K6783, Z1702, Z1709, for example. The thickness of the double-sided adhesive sheet 2a before and after heating is calculated according to the following formula. Thickness increase rate (%) = (thickness after heating-thickness before heating) × 100 / thickness before heating Furthermore, the coating step and the hardening step may be performed separately, but when the sealing material 40 is heated in the coating step, By this heating, the sealing material 40 can be hardened directly. That is, at that time, the coating step and the hardening step can be performed simultaneously.

Specific examples of the temperature at which the thermosetting resin composition is heated in the aforementioned coating step vary depending on the type of the sealing material 40 used, the type of the thermally expandable particles, and the like, but it is, for example, 30 to 180 ° C., preferably 50 to 170 ° C, more preferably 70 to 150 ° C. The heating time is, for example, 5 seconds to 60 minutes, preferably 10 seconds to 45 minutes, and more preferably 15 seconds to 30 minutes. Specific examples of the temperature at which the sealing material 40 is hardened in the aforementioned hardening step also vary depending on the type of the sealing material 40 used, the type of the thermally expandable particles, etc., but are, for example, 80 to 240 ° C, preferably 90 ~ 200 ° C, more preferably 100 to 170 ° C. The heating time is, for example, 10 to 180 minutes, preferably 20 to 150 minutes, and more preferably 30 to 120 minutes.

Here, in this embodiment, it is preferable to use a sheet-shaped packaging material (hereinafter, also referred to as "sheet-shaped packaging material"), and to perform a coating step and a curing step. (2) In the method using the sheet-shaped packaging material, the sheet-shaped packaging material is placed so as to cover the plurality of semiconductor wafers CP and the adhesive surface 30 on the peripheral portion of the plurality of semiconductor wafers CP, and is covered with the packaging material 40. At that time, in the gap between the semiconductor wafers CP, it is preferable to heat and press-bond while reducing the pressure appropriately by vacuum lamination or the like so as not to cause unfilled portions of the packaging material 40. Then, the laminated sealing material 40 is heated and hardened. A preferred aspect of the curing temperature is as described above. (2) The sheet-shaped packaging material may be a laminated sheet supported by a resin sheet such as polyethylene terephthalate. At this time, the sheet-like packaging material is placed so as to cover the plurality of semiconductor wafers CP and the adhesive surfaces 30 on the peripheral portions of the plurality of semiconductor wafers CP. After being covered with the packaging material 40, the resin sheet can be peeled from the packaging material 40.

In step (I-A2), a package body 50 in which a plurality of semiconductor wafers CP spaced apart from each other at a specific distance and embedded in the hardened packaging material 41 is obtained.

FIG. 7 (e) is a cross-sectional view illustrating a step of dividing the package into 50 pieces in units of a semiconductor wafer CP. In step (I-A3), 50 packages are divided into semiconductor wafer CP units. The method of forming 50 pieces of packages is not particularly limited, and can be implemented by a cutting means such as a dicing saw. (2) By dividing 50 packages into pieces, a package 50a of a semiconductor wafer CP unit is obtained. As a result, a plurality of packages 50 a are attached to the double-sided adhesive sheet 2 a as a process inspection object.

Here, in the above-mentioned embodiments of steps (I-A1) to (I-A3), the description of the redistribution layer formation step is omitted, but when the redistribution layer is formed, the redistribution layer formation step may be, for example, in step ( It is carried out between I-A2) and (I-A3) or after step (I-A3). (2) When the package is not peeled from the adhesive sheet, and the rewiring is formed, the rewiring layer is formed on the opposite side of the semiconductor wafer from the adhesive surface of the adhesive sheet (hereinafter, also referred to as the "package surface side"). When the redistribution layer is formed on the surface of the package, the metal terminal electrode on the circuit surface W1 of the semiconductor wafer is drawn from the circuit surface W1 through the periphery of the semiconductor wafer toward the surface of the package to produce a package. Then, after the package is formed, the package is ground from the front surface of the package to expose the metal terminal electrode, and then a redistribution layer is formed so as to be in contact with the exposed metal terminal electrode. However, it is not necessary to be limited to such a method. For example, in step (I-A1), the semiconductor wafer is placed such that the surface of the semiconductor wafer opposite to the circuit surface W1 is in contact with the adhesive surface of the adhesive sheet, and the semiconductor wafer is placed on the circuit surface W1. The metal terminal electrode system has a certain thickness (thickness in a direction perpendicular to the surface of the semiconductor wafer). Then, after the package is formed in the same manner as described above, the package is ground from the front surface of the package to expose the metal terminal electrode, and then a redistribution layer is formed so as to be in contact with the exposed metal terminal electrode.

(Steps (I-B1) to (I-B3)) 时 When a single-piece package is attached to a single-sided adhesive sheet, step (I) includes, for example, the following steps (I-B1) to (I-B3) ). The frame member used in step (I-B1) is the same as the "frame member 20" described in the above [step (I)], and includes one or more openings 21 penetrating the holes on the front surface and the back surface. Step (I-B1): a step of placing a plurality of semiconductor wafers on the adhesive surface of the adhesive layer (X1) exposed from the opening portion of the frame member while providing a gap between the semiconductor wafers adjacent to the semiconductor wafers Step (I-B2): Covering the plurality of semiconductor wafers and the adhesive surface of the peripheral portion of the plurality of semiconductor wafers and the adhesive surface of the gap with a packaging material, curing the packaging material, and obtaining the plurality of semiconductor wafers to be packaged The step of hardening the package made of the packaging material, (i) Step (I-B3): a step of singulating the package by the aforementioned semiconductor wafer unit. Hereinafter, each step will be described with reference to the drawings.

In steps (I-B1) to (I-B3), as shown in FIG. 8 (a), the frame member 20 having the opening 21 formed thereon is attached to the adhesive surface 121a of the adhesive layer (X1) 121. Sheet 1a is adhered on one side. Thereby, the single-sided adhesive sheet is supported by the frame member and is kept flat. Therefore, a package excellent in flatness can be obtained. In addition, the single-sided adhesive sheet is also excellent in operability, and a semiconductor wafer can be easily placed on the single-sided adhesive sheet. The structure and material of the frame member are as described above. Furthermore, the thickness of the frame member used in steps (I-B1) to (I-B3) is as described above, and is, for example, 100 μm to 3 mm, more preferably 100 μm to 1 mm, and even more preferably 100 to 500 μm. When the thickness of the frame member is 100 μm or more, warpage of the package can be suppressed even when a relatively wide area is packaged. When the thickness of the frame member is 3 mm or less, the productivity of the package can be prevented from being lowered.

Step (I-B1) is shown in Fig. 8 (b), step (I-B2) is shown in Figs. 8 (c) and 8 (d), and step (I-B3) is shown in Fig. 8 (e). The differences between steps (I-B1) to (I-B3) and steps (I-A1) to (I-A3) are the adhesives exposed at the openings of the frame members in step (I-B1) On the adhesive surface of the layer (X1), a gap is provided between the adjacent semiconductor wafers, and a plurality of semiconductor wafers are placed at the same time, and the others are common. Therefore, this common part can be implemented in the same manner as that described in steps (I-A1) to (I-A3). In the same manner as the above-mentioned embodiments of steps (I-A1) to (I-A3), when a redistribution layer is formed, the redistribution layer formation step is, for example, between steps (I-B2) and (I-B3). Occasionally after step (I-B3). Alternatively, the package that is selectively peeled through step (II) is implemented.

The adhesive sheet of this embodiment is used in the process of semiconductor packaging in the steps (I-A1) to (I-A3) or steps (I-B1) to (I-B3), which can solve the following problems: A positional deviation of the semiconductor wafer occurs between the mounting step and the packaging step of the semiconductor wafer, or the semiconductor wafer sinks into the adhesive sheet side, and the surface of the semiconductor wafer side of the package cannot be made flat. That is, in the adhesive sheet of this embodiment, since the non-adhesive base material having a high elastic modulus contains thermally expandable particles, the thickness, adhesive force, and viscoelastic modulus of the adhesive layer (X1) on which the semiconductor wafer is placed are adjusted. The degree of freedom of control and the like is increased. Thereby, the occurrence of the positional displacement of the semiconductor wafer can be suppressed, and the semiconductor wafer can be prevented from sinking into the adhesive sheet, so that a package having excellent flatness on the surface of the semiconductor wafer side can be formed. In addition, in the adhesive sheet of this embodiment, since the semiconductor wafer is placed on the adhesive surface of the adhesive layer (X1), the thermally expandable substrate does not directly contact the surface on the semiconductor wafer side of the package. As a result, it is possible to prevent a part of the residue from the thermally expandable particles and the greatly deformed adhesive layer from adhering to the surface of the semiconductor wafer side of the package or the uneven shape formed on the thermally expandable adhesive layer to be transferred to the semiconductor of the package. The surface of the wafer side has a reduced smoothness; the cleanliness and smoothness of the surface of the semiconductor wafer side of the package can be made excellent.

In addition, when the adhesive sheet of this embodiment, such as steps (I-A1) to (I-A3) or steps (I-B1) to (I-B3), is used in the manufacturing process of a semiconductor package, the use satisfies the above requirements. The thermally expandable substrate of (1) can more reliably prevent the positional shift of the processing inspection object of the semiconductor wafer and the like, and can also more reliably prevent the processing inspection object of the semiconductor wafer and the like from coming to the adhesive layer (X1). Fall into. In addition, the use of a thermally expandable substrate that satisfies the above-mentioned requirement (2) can be appropriately suppressed even in a temperature environment of a packaging step of a manufacturing process of a semiconductor package, such as a manufacturing process of a fan-out package such as FOWLP and FOPLP The flow of the thermally expandable particles makes it difficult to deform the adhesive surface of the adhesive layer (X1) provided on the thermally expandable substrate. As a result, it is possible to more surely prevent the positional deviation of the semiconductor wafer in the packaging step, and it is also possible to more surely prevent the semiconductor wafer from sinking into the adhesive layer (X1). Furthermore, since the ratio of the thickness of the thermally expandable substrate to the thickness of the adhesive layer (X1) (the thermally expandable substrate / adhesive layer (X1)) at 23 ° C is set to the above range, the semiconductor of the package can be made. The wafer-side surface becomes flatter, and the positional deviation of the semiconductor wafer can be prevented more reliably.

Further, in step (I), when the processing inspection object (package) is singulated on the adhesive sheet as described above, the entire processing inspection object (package) can be completely singulated. When step (II) is carried out, step (II) may be sequentially performed while the individual pieces of the processing inspection object (package) are being processed, and the processed inspection objects (package) that are singulated may be recovered.

Here, in this embodiment, after the packaging step, the entire adhesive sheet is heated to peel off the package, and then the package is attached to the new adhesive sheet. After the package is subjected to a rewiring layer forming step, The wafer unit is cut into individual pieces, and step (II) is performed, and only a part of the packaged pieces is selectively peeled from the adhesive sheet and separated. At this time, by using the above-mentioned adhesive sheet at the time of the packaging step, the occurrence of the positional displacement of the semiconductor wafer can be suppressed, and the semiconductor wafer can be prevented from sinking into the adhesive sheet. The package is subjected to selective peeling of the package.

Next, each constituent material and the like of the adhesive used in the present invention will be described in detail below.

[Thermally expandable base material] (1) The heat-expandable base material is a non-adhesive base material containing a resin and heat-expandable particles.

In the present invention, the judgment of whether the thermally expandable substrate is a non-adhesive substrate is the probe viscosity value measured on the surface of the target substrate according to JIS Z0237: 1991, as long as it does not reach 50mN / 5mmφ, The substrate is judged to be a "non-adhesive substrate". Here, the probe viscosity value on the surface of the thermally expandable substrate is usually less than 50mN / 5mmφ, preferably less than 30mN / 5mmφ, more preferably less than 10mN / 5mmφ, and even more preferably less than 5mN / 5mmφ. Furthermore, in this specification, the specific measurement method of the probe viscosity value on the surface of a thermally expandable base material is according to the method described in an Example.

The heat-expandable base material contains a resin and heat-expandable particles, but as long as the effect of the present invention is not impaired, an additive for the base material may be contained as necessary. In addition, the thermally expandable base material can be formed from a resin composition (y) containing a resin and thermally expandable particles. Hereinafter, each component contained in the resin composition (y) of the material which forms a thermally expandable base material is demonstrated.

[Resin] The resin contained in the resin composition (y) is not particularly limited as long as it is a non-adhesive resin having a thermally expandable base material, and may be a non-adhesive resin or an adhesive resin. That is, even if the resin contained in the resin composition (y) is an adhesive resin, as long as the adhesive resin and the polymerizable compound are polymerized during the process of forming a thermally expandable base material from the resin composition (y), The obtained resin may be a non-adhesive resin, and the thermally expandable substrate containing the resin may be non-adhesive.

The mass average molecular weight (Mw) of the resin contained in the resin composition (y) is preferably 10 to 1 million, more preferably 10 to 700,000, and even more preferably 10 to 500,000. In addition, when the resin is a copolymer having two or more constituent units, the morphology of the copolymer is not particularly limited, and may be any of a block copolymer, a random copolymer, and a graft copolymer.

The content of the aforementioned resin is preferably 50 to 99% by mass, more preferably 60 to 95% by mass, and even more preferably 65 to 90% by mass, with respect to the total amount (100% by mass) of the active ingredient of the resin composition (y). It is more preferably 70 to 85% by mass.

As said resin contained in resin composition (y), it is preferable to contain 1 or more types chosen from an acrylic urethane-type resin and an olefin-type resin. As the acrylic urethane resin, the following resin (U1) is preferred. (2) An acrylic urethane resin (U1) obtained by polymerizing a urethane prepolymer (UP) and a vinyl compound containing a (meth) acrylate.

(Acrylic urethane-based resin (U1)) As the urethane prepolymer (UP) which is the main chain of the acrylic urethane-based resin (U1), polyhydric alcohols and polyhydric Isocyanate reactant. Furthermore, the urethane prepolymer (UP) is preferably obtained by further applying a chain extension reaction using a chain extender.

Examples of the polyol used as a raw material of the urethane prepolymer (UP) include an alkylene polyol, an ether polyol, an ester polyol, an esteramine polyol, and an ester. Ether polyols and carbonate polyols. These polyhydric alcohols can be used alone or in combination of two or more kinds as the polyhydric alcohol used in this embodiment, preferably a diol, more preferably an ester-type diol, an alkylene-type diol, and a carbonate-type dihydric alcohol. The alcohol is particularly preferably an ester-type diol and a carbonate-type diol.

Examples of the ester diol include alkanediols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, and 1,6-hexanediol. ; One or more selected from glycols such as ethylene glycol, propylene glycol, diethylene glycol, and alkanediols such as dipropylene glycol; and phthalic acid, isophthalic acid, terephthalic acid, Naphthalenedicarboxylic acid, 4,4-diphenyldicarboxylic acid, diphenylmethane-4,4'-dicarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, chlorobridged acid, horse Maleic acid, fumaric acid, itaconic acid, cyclohexane-1,3-dicarboxylic acid, cyclohexane-1,4-dicarboxylic acid, hexahydrophthalic acid, hexahydroisophthalic acid, hexacarboxylic acid One or two or more kinds of polycondensates selected from dicarboxylic acids such as hydroterephthalic acid and methylhexahydrophthalic acid and anhydrides thereof. Specific examples include polyethylene adipate diol, polybutylene adipate diol, polyadiene adipate diol, polyisopropyl adipate diol, and polyhexamethylene adipate. Neopentyl didiol, polyethylene adipate glycol, polyethylene adipate glycol, polybutylene adipate glycol, polypoly adipate Ethylene glycol, poly (poly-p-methylene ether) adipate diol, poly (3-methylpentyl adipate) diol, polyethylene azelate diol, poly Ethylene glycol sebacate, polybutylene azelate glycol, polybutylene sebacate glycol, and neopentyl terephthalate glycol.

Examples of the alkylene type diol include alkane diols such as 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, and 1,6-hexanediol. Alcohols; alkanediols such as ethylene glycol, propylene glycol, diethylene glycol, and dipropylene glycol; polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polybutylene glycol; polytetramethylene glycol, and other polymers Alkylene glycol and the like.

Examples of the carbonate-type diol include 1,4-tetramethylene carbonate diol, 1,5-pentamethylene carbonate diol, 1,6-hexamethylene carbonate diol, 1,2-Butyl carbonate diol, 1,3-Butyl carbonate diol, 2,2-Dimethyl propylene carbonate diol, 1,7-Heptamethylene carbonate bis Alcohols, 1,8-octamethylene carbonate diols, 1,4-cyclohexane carbonate diols, and the like.

Examples of the polyisocyanate used as a raw material of the urethane prepolymer (UP) include an aromatic polyisocyanate, an aliphatic polyisocyanate, and an alicyclic polyisocyanate. These polyisocyanates can be used alone or in combination of two or more. In addition, these polyisocyanates can also be trimethylolpropane addition-shaped modifiers, biuret-type modifiers that react with water, and isotricyanates containing isocyanurate rings. Modified body.

Among these, as the polyisocyanate used in this embodiment, diisocyanate is preferred, and 4,4'-diphenylmethane diisocyanate (MDI), 2,4-toluene diisocyanate (2, 4-TDI), 2,6-toluene diisocyanate (2,6-TDI), hexamethylene diisocyanate (HMDI), and one or more selected from alicyclic diisocyanates.

Examples of the alicyclic diisocyanate include 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), 1,3-cyclopentane diisocyanate, 1,3-cyclohexane diisocyanate, 1,4-cyclohexane diisocyanate, methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, and the like are preferred, Isophorone diisocyanate (IPDI).

In this embodiment, the urethane prepolymer (UP) as the main chain of the acrylic urethane resin (U1) is preferably a reactant of a diol and a diisocyanate. A linear urethane prepolymer having an ethylenically unsaturated group at the terminal. Examples of a method for introducing an ethylenically unsaturated group at both ends of the linear urethane prepolymer include a linear urethane prepolymer obtained by reacting a diol with a diisocyanate compound. A method for reacting a terminal NCO group with a hydroxyalkyl (meth) acrylate.

Examples of the hydroxyalkyl (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and (methyl) ) 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and the like.

The vinyl compound as a side chain of the acrylic urethane resin (U1) contains at least a (meth) acrylate. The (meth) acrylate is preferably one or more selected from alkyl (meth) acrylate and hydroxyalkyl (meth) acrylate, and more preferably a combination of alkyl (meth) acrylate and (meth) ) Hydroxyalkyl acrylate.

When an alkyl (meth) acrylate and a hydroxyalkyl (meth) acrylate are used together, the blending ratio of the hydroxyalkyl (meth) acrylate is preferably 0.1 to 100 with respect to 100 parts by mass of the (meth) acrylate. It is more preferably 0.5 to 30 parts by mass, more preferably 1.0 to 20 parts by mass, and even more preferably 1.5 to 10 parts by mass.

The number of carbon atoms of the alkyl group possessed by the alkyl (meth) acrylate is preferably 1 to 24, more preferably 1 to 12, particularly preferably 1 to 8, and even more preferably 1 to 3.

Moreover, as a hydroxyalkyl (meth) acrylate, the hydroxyalkyl (meth) acrylate used for the introduction of an ethylenically unsaturated group at the both ends of the said linear urethane prepolymer is mentioned. The same.

Examples of vinyl compounds other than (meth) acrylates include aromatic hydrocarbon-based vinyl compounds such as styrene, a-methylstyrene, and vinyl toluene; methyl vinyl ether and ethyl vinyl Vinyl ethers such as ethers; vinyl acetate, vinyl propionate, (meth) acrylonitrile, N-vinylpyrrolidone, (meth) acrylic acid, maleic acid, fumaric acid, itaconic acid and A polar group-containing monomer such as methyl (acrylamide) and the like.系 These systems can be used alone or in combination of two or more.

The content of the (meth) acrylic acid ester in the vinyl compound is preferably 40 to 100% by mass, more preferably 65 to 100% by mass, and even more preferably 65% to 100% by mass relative to the total amount (100% by mass) of the vinyl compound. 80 to 100% by mass, and more preferably 90 to 100% by mass.

The total content of the (meth) acrylic acid alkyl ester and the (meth) acrylic acid hydroxyalkyl ester in the vinyl compound is preferably 40 to 100 mass% relative to the total amount (100% by mass) of the vinyl compound, and more preferably It is preferably 65 to 100% by mass, particularly preferably 80 to 100% by mass, and even more preferably 90 to 100% by mass.

The acrylic urethane resin (U1) used in this embodiment is obtained by mixing a urethane prepolymer (UP) and a vinyl compound containing a (meth) acrylate, and polymerizing the two. .聚合 The polymerization is preferably carried out by further adding a radical initiator.

The content of the structural unit (u11) derived from the urethane prepolymer (UP) and the structural unit (u12) derived from the vinyl compound in the acrylic urethane resin (U1) used in this embodiment. The ratio [(u11) / (u12)] is in terms of mass ratio, preferably 10/90 to 80/20, more preferably 20/80 to 70/30, particularly preferably 30/70 to 60/40, especially More preferably, it is 35/65 to 55/45.

(Olefin-based resin) A suitable olefin-based resin of the resin contained in the resin composition (y) is a polymer having at least a constituent unit derived from an olefin monomer. As the olefin monomer, an a-olefin having 2 to 8 carbon atoms is preferred, and specific examples include ethylene, propylene, butene, isobutylene, and 1-hexene. Among these, ethylene and propylene are preferred.

Specific examples of the olefin resin include ultra-low density polyethylene (VLDPE, density: 880 kg / m ³ or more and less than 910 kg / m ³ ), and low density polyethylene (LDPE, density: 910 kg / m ³ or more) And less than 915 kg / m ³ ), medium density polyethylene (MDPE, density: 915 kg / m ³ or more and less than 942 kg / m ³ ), high density polyethylene (HDPE, density: 942 kg / m ³ or more), and straight chain Polyethylene resin such as low density polyethylene; polypropylene resin (PP); polybutene resin (PB); ethylene-propylene copolymer; olefin-based elastomer (TPO); poly (4-methyl-1-pentane) Olefin) (PMP); ethylene-vinyl acetate copolymer (EVA); ethylene-vinyl alcohol copolymer (EVOH); olefin-based ternary such as ethylene-propylene- (5-ethylidene-2-norbornene) Copolymers, etc.

In this embodiment, the olefin-based resin may be a modified olefin-based resin further provided with one or more types selected from acid modification, hydroxyl modification, and acrylic modification.

For example, examples of the acid-modified olefin-based resin obtained by subjecting the olefin-based resin to acid modification include modification of the non-modified olefin-based resin by graft polymerization of an unsaturated carboxylic acid or an anhydride thereof. Qualitative polymer. Examples of the unsaturated carboxylic acid or its anhydride include maleic acid, fumaric acid, itaconic acid, citraconic acid, glutaric acid, tetrahydrophthalic acid, aconitic acid, and (meth) acrylic acid. , Maleic anhydride, itaconic anhydride, glutaric anhydride, citraconic anhydride, aconitic anhydride, norbornene dicarboxylic anhydride, and tetrahydrophthalic anhydride. Furthermore, the unsaturated carboxylic acid or its anhydride may be used alone or in combination of two or more.

Examples of the acrylic-modified olefin-based resin obtained by modifying acrylic resin with olefin-based resin include the above-mentioned unmodified olefin-based resin as a main chain, and (meth) acrylic acid alkyl group as a side chain by graft polymerization. Ester modified polymer. (1) The number of carbon atoms of the alkyl group in the alkyl (meth) acrylate is preferably 1 to 20, more preferably 1 to 16, and even more preferably 1 to 12. As the alkyl (meth) acrylate, for example, the same compounds as those which can be selected as the monomer (a1 ') described later can be mentioned.

Examples of the hydroxy-modified olefin resin obtained by subjecting the olefin-based resin to hydroxyl modification include modified polymerization of a hydroxyl-containing compound by graft polymerization of the above-mentioned non-modified olefin-based resin as a main chain. Thing. Examples of the hydroxyl-containing compound include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and (meth) propylene 2 -Hydroxy (meth) acrylates such as hydroxybutyrate, 3-hydroxybutyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate; unsaturated alcohols such as vinyl alcohol and allyl alcohol Class, etc.

(Resins other than acrylic urethane-based resin and olefin-based resin) 丙烯酸 In this embodiment, the resin composition (y) may also contain acrylic methacrylate as long as the effect of the present invention is not impaired. Resins other than ester resins and olefin resins. Examples of such resins include vinyl resins such as polyvinyl chloride, polyvinylidene chloride, and polyvinyl alcohol; polyethylene terephthalate, polybutylene terephthalate, and polynaphthalene dicarboxylic acid. Polyester resins such as ethylene glycol; polystyrene; acrylonitrile-butadiene-styrene copolymer; cellulose triacetate; polycarbonate; polyamines not equivalent to acrylic urethane resins Formates; Polyfluorene; Polyetheretherketone; Polyetherfluorene; Polyphenylenesulfide; Polyetherimide resins such as polyetherimide, polyimide, etc .; Polyammonium resin; Acrylic resin; Fluorine Resin, etc. The content ratio of the resin other than the acrylic urethane-based resin and the olefin-based resin is preferably less than 30 parts by mass with respect to 100 parts by mass of the total amount of the resin contained in the resin composition (y), and more preferably It is less than 20 parts by mass, more preferably less than 10 parts by mass, particularly preferably less than 5 parts by mass, and even more preferably less than 1 part by mass.

[Thermally expandable particles] The heat-expandable particles may be particles that are expanded by heating, but it is preferable to use particles whose expansion start temperature (t) is adjusted to 120 to 250 ° C. The expansion start temperature (t) is appropriately selected depending on the application. In addition, in this specification, the expansion start temperature (t) of a thermally expandable particle means the value measured by the following method. (Measurement method for the expansion start temperature (t) of thermally expandable particles) In an aluminum cup with a diameter of 6.0 mm (inner diameter 5.65 mm) and a depth of 4.8 mm, add 0.5 mg of the thermally expandable particles as the measurement object, and prepare it on top of it. Samples with aluminum caps (diameter 5.6mm, thickness 0.1mm). Using a dynamic viscoelasticity measuring device, the height of the sample was measured with a force of 0.01 N applied from the upper part of the aluminum cover by a pressure head. Then, in a state where a force of 0.01 N is applied by the pressure head, the heating is performed at a heating rate of 10 ° C./min from 20 ° C. to 300 ° C., and the displacement in the vertical direction of the pressure head is measured, and it will be positive. The displacement start temperature is taken as the expansion start temperature (t).

The heat-expandable particles are preferably a microencapsulated foaming agent composed of an outer casing made of a thermoplastic resin and an inner inclusion component that is enclosed in the outer casing and vaporizes when heated to a specific temperature. Examples of the thermoplastic resin constituting the shell of the microencapsulated foaming agent include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, and poly Vinylidene chloride and polyfluorene.

Examples of the internal components contained in the outer shell include propane, butane, pentane, hexane, heptane, octane, nonane, decane, isobutane, isopentane, isohexane, isopropyl Heptane, isooctane, isononane, isodecane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, cycloheptane, cyclooctane, neopentane, dodecane, isododecane , Cyclotridecane, hexylcyclohexane, tridecane, tetradecane, pentadecane, hexadecane, heptadecane, octadecane, nonadecane, isotridecane, 4-methyldodecane Alkane, isotetradecane, isopentadecane, isohexadecane, 2,2,4,4,6,8,8-heptamethylnonane, isohexadecane, isooctadecane, iso19 Alkane, 2,6,10,14-tetramethylpentadecane, cyclotridecane, heptylcyclohexane, n-octylcyclohexane, cyclopentadecane, nonylcyclohexane, decylcyclohexane Alkanes, pentadecylcyclohexane, hexadecylcyclohexane, heptylcyclohexane and octadecylcyclohexane.内 These enclosed ingredients can be used alone or in combination of two or more.膨胀 The expansion start temperature (t) of the thermally expandable particles can be adjusted by appropriately selecting the type of the inclusion component.

In this embodiment, the average particle diameter of the thermally expandable particles before expansion at 23 ° C. is preferably 3 to 100 μm, more preferably 4 to 70 μm, even more preferably 6 to 60 μm, even more preferably 10 to 50 μm. The average particle size before expansion of the thermally expandable particles is the volume median particle size (D ₅₀ ), which means that a laser diffraction particle size distribution measuring device (for example, manufactured by Malvern, product name "Mastersizer 3000" is used). ") It is determined that in the particle distribution of the heat-expandable particles before expansion, the cumulative volume frequency calculated from the smaller particle size of the heat-expandable particles before expansion corresponds to a particle size of 50%.

In this embodiment, the 90% particle diameter (D ₉₀ ) of the thermally expandable particles before expansion at 23 ° C. is preferably 10 to 150 μm, more preferably 20 to 100 μm, even more preferably 25 to 90 μm, and even more preferably 30 to 80 μm. The 90% particle size (D ₉₀ ) before the expansion of the thermally expandable particles is measured using a laser diffraction particle size distribution measuring device (for example, manufactured by Malvern, product name "Mastersizer 3000"), In the particle distribution of the heat-expandable particles before expansion, the cumulative volume frequency calculated from the smaller particle size of the heat-expandable particles corresponds to a particle size of 90%.

The maximum volume expansion rate when heated to a temperature greater than the expansion start temperature (t) of the thermally expandable particles used in this embodiment is preferably 1.5 to 100 times, more preferably 2 to 80 times, and even more preferably 2.5 to 60 times. , Especially more preferably 3 to 40 times.

The content of the heat-expandable particles is preferably 1 to 40% by mass, more preferably 5 to 35% by mass, and even more preferably 10 to 30% by mass, relative to the total amount (100% by mass) of the effective components of the resin composition (y). And more preferably 15 to 25% by mass.

[Additives for Substrates] The resin composition (y) used in the present embodiment may contain additives for substrates contained in a substrate included in a general adhesive sheet, as long as the effects of the present invention are not impaired. Examples of such additives for substrates include ultraviolet absorbers, light stabilizers, antioxidants, antistatic agents, slip agents, anti-blocking agents, and coloring agents. Furthermore, these additives for base materials may be used individually or in combination of 2 or more types. When these additives for substrates are contained, the content of the additives for each substrate is preferably 0.0001 to 20 parts by mass, and more preferably 0.001 to 10 parts by mass relative to 100 parts by mass of the resin in the resin composition (y). Serving.

(Solventless resin composition (y1)) As the resin composition (y) used in this embodiment, oligomers having an ethylenically unsaturated group with a mass average molecular weight (Mw) of 50,000 or less, A solvent-free resin composition (y1) composed of an energy ray polymerizable monomer and the above-mentioned swellable particles, and without a solvent. In the solvent-free resin composition (y1), no solvent is blended, but the energy ray polymerizable single system contributes to the improvement of the plasticity of the aforementioned oligomer. A coating film formed of a solventless resin composition (y1) can be irradiated with energy rays to form a thermally expandable substrate.

The types, shapes, and blending amounts (contents) of the expandable particles blended in the solventless resin composition (y1) are as described above.

The mass average molecular weight (Mw) of the aforementioned oligomer contained in the solventless resin composition (y1) is 50,000 or less, preferably 1,000 to 50,000, more preferably 2,000 to 40,000, particularly preferably 3,000 to 35,000, especially More preferably, it is 4,000 to 30,000.

In addition, as the oligomer, among the resins contained in the resin composition (y), any resin having an ethylenically unsaturated group with a mass average molecular weight (Mw) of 50,000 or less may be used, but the above is preferred. Urethane prepolymer (UP). Furthermore, as the oligomer, a modified olefin-based resin having an ethylenically unsaturated group or the like can also be used.

The total content of the oligomer and the energy ray polymerizable monomer in the solventless resin composition (y1) is preferably 50 relative to the total amount (100% by mass) of the solventless resin composition (y1). -99 mass%, more preferably 60-95 mass%, particularly preferably 65-90 mass%, and even more preferably 70-85 mass%.

Examples of the energy ray polymerizable monomer include isobornyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentyl (meth) acrylate, and dicyclopentyl (meth) acrylate. Alicyclic polymerizable compounds such as enoxylate, cyclohexyl (meth) acrylate, adamantane (meth) acrylate, and tricyclodecane acrylate; phenylhydroxypropyl acrylate, benzyl acrylate, and phenol ring Aromatic polymerizable compounds such as ethylene oxide modified acrylate; heterocyclic rings such as tetrahydrofurfuryl (meth) acrylate, morpholine acrylate, N-vinylpyrrolidone, and N-vinylcaprolactam Formula polymerizable compounds and the like. These energy ray polymerizable single systems can be used alone or in combination of two or more.

The content ratio of the oligomer to the energy ray polymerizable monomer in the solvent-free resin composition (y1) [oligomer / energy ray polymerizable monomer] is a mass ratio, preferably 20/80 ～ 90/10, more preferably 30/70 to 85/15, and particularly preferably 35/65 to 80/20.

In this embodiment, the solventless resin composition (y1) is preferably formed by further blending a photopolymerization initiator. Since it contains a photopolymerization initiator, the hardening reaction can proceed sufficiently even by irradiation with a relatively low energy energy ray.

Examples of the photopolymerization initiator include 1-hydroxy-cyclohexyl-phenyl-one, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, and benzyl Phenyl sulfide, tetramethylthiuram monosulfide, azobisisobutyronitrile, bibenzyl, biacetamidine and 8-chloroanthraquinone. These photopolymerization initiators may be used alone or in combination of two or more.

The blending amount of the photopolymerization initiator is preferably 0.01 to 5 parts by mass, more preferably 0.01 to 4 parts by mass, and even more preferably the entire amount (100 parts by mass) of the aforementioned oligomer and energy ray polymerizable monomer. It is 0.02 to 3 parts by mass.

[Adhesive layer (X1)] 的 The adhesive layer (X1) included in the adhesive sheet of this embodiment is not limited as long as it contains an adhesive resin, and it may contain a crosslinking agent, a tackifier, and a polymerizable compound as needed. Additives for adhesives such as polymerization initiators.

In the adhesive sheet of this embodiment, the adhesive force of the adhesive surface of the adhesive layer (X1) at 23 ° C. before expansion of the thermally expandable particles is preferably 0.1 to 10.0 N / 25 mm, and more preferably 0.2 to 8.0 N / 25mm, particularly preferably 0.4 to 6.0N / 25mm, and even more preferably 0.5 to 4.0N / 25mm. If the adhesive force is 0.1N / 25mm or more, it is possible to prevent the position of the adherend from shifting to a sufficient degree and sufficiently fix it. In addition, it is possible to prevent the degree of positional deviation of the semiconductor wafer in the above-mentioned packaging step from being sufficiently fixed. On the other hand, if the adhesive force is 10.0 N / 25 mm or less, when the adherend is peeled off and separated, it can be easily separated. Furthermore, the above-mentioned adhesive force means a value measured by the method described in the examples.

The adhesive layer (X1) can be formed from an adhesive composition containing an adhesive resin. Hereinafter, each component contained in the adhesive composition which is a material for forming the adhesive layer (X1) will be described.

[Adhesive Resin] As the adhesive resin used in this embodiment, a polymer having adhesiveness alone and a mass average molecular weight (Mw) of 10,000 or more is preferred. From the viewpoint of improving the adhesive force, the mass average molecular weight (Mw) of the adhesive resin used in this embodiment is more preferably 10,000 to 2 million, particularly preferably 20,000 to 1.5 million, and even more preferably 30,000 to 1000000.

Examples of the adhesive resin include rubber-based resins such as acrylic resins, urethane-based resins, and polyisobutylene-based resins, polyester-based resins, olefin-based resins, silicone resins, and polyvinyl ethers. Department of resin and so on. These adhesive resins can be used alone or in combination of two or more. When the adhesive resin is a copolymer having two or more kinds of constituent units, the morphology of the copolymer is not particularly limited, and may be a block copolymer, a random copolymer, and a graft copolymer. Either.

The adhesive resin used in this embodiment may also be an energy ray-curable adhesive resin having a polymerizable functional group introduced into a side chain of the above-mentioned adhesive resin. Examples of the polymerizable functional group include a (meth) acrylic acid fluorenyl group and a vinyl group. In addition, examples of the energy rays include ultraviolet rays and electron rays, and ultraviolet rays are preferred.

The content of the adhesive resin is preferably 30 to 99.99% by mass, more preferably 40 to 99.95% by mass, and even more preferably 50 to 99.90% by mass, especially relative to the total amount (100% by mass) of the active ingredient of the adhesive composition. It is more preferably 55 to 99.80% by mass, and particularly preferably 60 to 99.50% by mass. In addition, in the following description of the present specification, "the content of each component with respect to the total amount of the active ingredients of the adhesive composition" means "each component in the adhesive layer formed from the adhesive composition" "Content" is synonymous.

In this embodiment, from the standpoint that it exhibits excellent adhesion and expands the thermally expandable particles in the thermally expandable substrate by heat treatment, and it is easy to form irregularities on the adhesive surface of the adhesive layer (X1). The resin is preferably an acrylic resin. The content of the acrylic resin in the adhesive resin is preferably 30 to 100% by mass, and more preferably 50 to 100% by mass, with respect to the total amount (100% by mass) of the adhesive resin contained in the adhesive composition. It is particularly preferably 70 to 100% by mass, and even more preferably 85 to 100% by mass.

(Acrylic resin) In the present embodiment, examples of the acrylic resin that can be used as an adhesive resin include those containing a structural unit derived from an alkyl (meth) acrylate having a linear or branched alkyl group. A polymer, a polymer containing a structural unit derived from a (meth) acrylate having a cyclic structure, and the like.

The mass average molecular weight (Mw) of the acrylic resin is preferably 100,000 to 1.5 million, more preferably 200,000 to 1.3 million, particularly preferably 350,000 to 1.2 million, and even more preferably 500,000 to 1.1 million.

The acrylic resin is more preferably a structural unit (a1) derived from an alkyl (meth) acrylate (a1 ') (hereinafter, also referred to as "monomer (a1')") and a functional group-containing monomer. (a2 ') (hereinafter, also referred to as "monomer (a2')") is an acrylic copolymer (A1) of a structural unit (a2).

The number of carbon atoms of the alkyl group in the monomer (a1 ') is preferably from 1 to 24, more preferably from 1 to 12, particularly preferably from 2 to 10, and even more preferably 4 from the viewpoint of improving the adhesion characteristics. ~ 8. In addition, the alkyl system of the monomer (a1 ') may be a linear alkyl group or a branched alkyl group.

Examples of the monomer (a1 ') include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and (meth) acrylic acid 2 -Ethylhexyl ester, lauryl (meth) acrylate, tridecyl (meth) acrylate, octadecyl (meth) acrylate, and the like. These monomers (a1 ') may be used alone or in combination of two or more kinds. As the monomer (a1 '), butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate are preferred.

The content of the constituent unit (a1) is preferably 50 to 99.9 mass%, more preferably 60 to 99.0 mass%, and even more preferably 70 to 97.0, with respect to all the constituent units (100 mass%) of the acrylic copolymer (A1). Mass%, particularly preferably 80 to 95.0 mass%.

As a functional group which a monomer (a2 ') has, a hydroxyl group, a carboxyl group, an amine group, an epoxy group, etc. are mentioned, for example. That is, examples of the monomer (a2 ') include a hydroxyl-containing monomer, a carboxyl-containing monomer, an amine-containing monomer, and an epoxy-containing monomer. These monomers (a2 ') may be used alone or in combination of two or more kinds. Among these, as the monomer (a2 '), a hydroxyl-containing monomer and a carboxyl-containing monomer are preferred.

Examples of the hydroxyl-containing monomer include the same ones as the above-mentioned hydroxyl-containing compound.

Examples of the carboxyl group-containing monomer include ethylenically unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid; and ethylenically unsaturated monomers such as fumaric acid, itaconic acid, maleic acid, and citraconic acid. Dicarboxylic acids and their anhydrides, 2- (propenyloxy) ethyl succinate and 2-carboxyethyl (meth) acrylate.

The content of the structural unit (a2) is preferably 0.1 to 40% by mass, more preferably 0.5 to 35% by mass, and even more preferably 1.0 to 30, with respect to all the structural units (100% by mass) of the acrylic copolymer (A1). Mass%, particularly preferably 3.0 to 25 mass%.

The acrylic copolymer (A1) may further have a structural unit (a3) derived from a monomer (a3 ') other than the monomers (a1') and (a2 '). In addition, in the acrylic copolymer (A1), the content of the constituent units (a1) and (a2) is preferably 70 to 100 mass relative to all the constituent units (100% by mass) of the acrylic copolymer (A1). %, More preferably 80 to 100% by mass, even more preferably 90 to 100% by mass, even more preferably 95 to 100% by mass.

Examples of the monomer (a3 ') include olefins such as ethylene, propylene, and isobutene; halogenated olefins such as vinyl chloride and vinylidene chloride; and butadiene, isoprene, and chloroprene. Diene monomers; cyclohexyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, dicyclopentyl (meth) acrylate, and dicyclo (meth) acrylate (Meth) acrylic esters having a cyclic structure such as pentenyl ester, dicyclopentenyloxyethyl (meth) acrylate, and imidate (meth) acrylate; styrene, a-methylstyrene , Vinyl toluene, vinyl formate, vinyl acetate, acrylonitrile, (meth) acrylamide, (meth) acrylonitrile, (meth) acrylfluorenylmorpholine, N-vinylpyrrolidone, and the like.

The acrylic copolymer (A1) may be an energy ray-curable acrylic copolymer having a polymerizable functional group introduced into a side chain. The polymerizable functional group and the energy ray are as described above. Furthermore, the polymerizable functional group can be obtained by allowing the acrylic copolymer having the above-mentioned constitutional units (a1) and (a2) and the functional group having the constitutional unit (a2) with the acrylic copolymer The compound of the bonded substituent and the polymerizable functional group is introduced and reacted. As the aforementioned compound, for example, (meth) acrylic ethoxyethyl isocyanate, (meth) acryl fluorenyl isocyanate, and (meth) acrylic acid propylene oxide are mentioned.

(Crosslinking agent) In the present embodiment, when the adhesive composition contains a functional group-containing adhesive resin such as the acrylic copolymer (A1) described above, it is preferable to further contain a crosslinking agent. The crosslinking agent reacts with an adhesive resin having a functional group, and uses the functional group as a starting point for crosslinking to crosslink the adhesive resins.

Examples of the crosslinking agent include an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, an aziridine-based crosslinking agent, and a metal chelate-based crosslinking agent. These crosslinking agents may be used alone or in combination of two or more kinds. Among these cross-linking agents, an isocyanate-based cross-linking agent is preferred from the viewpoint of improving cohesion and increasing the adhesive force, and from the viewpoint of easiness of obtaining.

The content of the crosslinking agent can be appropriately adjusted according to the number of functional groups of the adhesive resin. For example, it is preferably 0.01 to 10 parts by mass, and more preferably 0.03 to 100 parts by mass of the adhesive resin having functional groups. 7 parts by mass, particularly preferably from 0.05 to 5 parts by mass.

(Tackifier) In this embodiment, from the viewpoint of further improving the adhesive force, the adhesive composition system may further contain a tackifier. In this specification, the so-called "tackifier" refers to a component that assists in improving the adhesion of the above-mentioned adhesive resin, and refers to an oligomer having a mass average molecular weight (Mw) of less than 10,000 and the above-mentioned adhesive resin. The difference.质量 The mass average molecular weight (Mw) of the tackifier is preferably 400 to less than 10,000, more preferably 500 to 8000, and even more preferably 800 to 5000.

Examples of the tackifier include rosin-based resins, terpene-based resins, styrene-based resins, copolymerization of pentene, isoprene, piperine, and 1,3-pentane produced by thermal decomposition of petroleum naphtha. C5 based petroleum resins obtained from C5 fractions such as olefins, C9 based petroleum resins obtained by copolymerizing C9 fractions such as indene and vinyltoluene produced by thermal decomposition of petroleum brain, and hydrogenated resins such as these.

The softening point of the tackifier is preferably 60 to 170 ° C, more preferably 65 to 160 ° C, and even more preferably 70 to 150 ° C. Furthermore, in this specification, the "softening point" of a tackifier means the value measured based on JISK2531.黏 Tackifiers can be used alone or in combination of two or more different softening points and structures. Furthermore, when two or more kinds of plural thickeners are used, the weighted average of the softening points of the plural thickeners preferably falls within the aforementioned range.

The content of the tackifier is preferably 0.01 to 65% by mass, more preferably 0.05 to 55% by mass, and even more preferably 0.1 to 50% by mass, especially relative to the total amount (100% by mass) of the active ingredient of the adhesive composition. It is more preferably 0.5 to 45% by mass, and particularly preferably 1.0 to 40% by mass.

(Photopolymerization initiator) In the present embodiment, when the adhesive composition contains an energy ray-curable adhesive resin as the adhesive resin, it is preferable to further contain a photopolymerization initiator. Since it is an adhesive composition containing an energy ray-curable adhesive resin and a photopolymerization initiator, the adhesive layer (X1) formed from the adhesive composition is irradiated with a relatively low energy energy ray, It is also possible to sufficiently advance the hardening reaction and adjust the adhesion to a desired range. Furthermore, examples of the photopolymerization initiator used in the present embodiment include the same as those incorporated in the above-mentioned solventless resin composition (y1).

The content of the photopolymerization initiator is preferably 0.01 to 10 parts by mass, more preferably 0.03 to 5 parts by mass, and even more preferably 0.05 to 2 parts by mass with respect to 100 parts by mass of the energy ray-curable adhesive resin.

(Additives for Adhesives) In this embodiment, as long as the effects of the present invention are not impaired, the adhesive composition system of the material for forming the adhesive layer (X1) may contain general adhesives in addition to the additives described above. Additives used in adhesives. Examples of such additives for adhesives include antioxidants, softeners (plasticizers), rust inhibitors, pigments, dyes, retarders, reaction accelerators (catalysts), and ultraviolet absorbers. Moreover, these additives for adhesives may be used individually or in combination of 2 or more types.

When these additives for adhesives are contained, the content of the respective additives for adhesives is preferably 0.0001 to 20 parts by mass, and more preferably 0.001 to 10 parts by mass, with respect to 100 parts by mass of the adhesive resin.

In addition, the adhesive layer (X1) included in the adhesive sheet of the present embodiment suppresses the residue from the thermally expandable particles from adhering to the surface of the object to be inspected, or is thermally peeled off due to the adhesive residue on the surface of the object to be inspected. From the viewpoint of contamination on the surface of a processing inspection object, a non-swellable adhesive layer is preferred. The content of the thermally expandable particles in the adhesive layer (X1) is preferably relative to the total amount (100% by mass) of the active ingredients of the adhesive composition or the total mass (100% by mass) of the adhesive layer (X1). It is less than 1% by mass, more preferably less than 0.1% by mass, particularly preferably less than 0.01% by mass, and even more preferably less than 0.001% by mass.

[Adhesive layer (X2)] When the adhesive sheet of this embodiment is a double-sided adhesive sheet, as long as the adhesive layer (X2) included in the double-sided adhesive sheet contains an adhesive resin, it may also contain a cross-linking agent if necessary. Additives for adhesives such as crosslinking agents, tackifiers, polymerizable compounds, and polymerization initiators.较佳 The preferred form of the composition and morphology of the adhesive layer (X2) is the same as that of the adhesive layer (X1). However, the composition of the adhesive layer (X1) and the adhesive layer (X2) may be the same or different. The morphology of the adhesive layer (X1) and the adhesive layer (X2) may be the same or different. In addition, the adhesive layer (X2) included in the adhesive sheet of this embodiment is preferable from the viewpoint of maintaining the adhesive force with the hard support during heating and maintaining the adhesive layer (X1). It is also a non-swellable adhesive layer. The content of the thermally expandable particles in the adhesive layer (X2) is preferably relative to the total amount (100% by mass) of the active ingredient of the adhesive composition or the total mass (100% by mass) of the adhesive layer (X2). It is less than 1% by mass, more preferably less than 0.1% by mass, particularly preferably less than 0.01% by mass, and even more preferably less than 0.001% by mass.

In addition, the storage shear modulus G '(23) at 23 ° C of the adhesive layer (X2) is preferably 1.0 × 10 ⁴ ～ from the viewpoint of improving the adhesion to the hard support. 1.0 × 10 ⁸ Pa, more preferably 3.0 × 10 ⁴ to 5.0 × 10 ⁷ Pa, and even more preferably 5.0 × 10 ⁴ to 1.0 × 10 ⁷ Pa.

[Peeling material] 双面 The double-sided adhesive sheet of this embodiment is the adhesive sheet 1b shown in FIG. 1 (b) and the adhesive sheet 2b shown in FIG. 2 (b), and can also be used in the adhesive layer (X1) and / or On the adhesive surface of the adhesive layer (X2), a release material is further provided. Moreover, as shown in FIG. 2 (b), the adhesive sheet 2b is provided in the adhesive layer (X1) and the adhesive in the double-sided adhesive sheet having the adhesive layer (X1) and the adhesive layer (X2). It is preferable that the two release materials on the respective adhesive surfaces of the layer (X2) are adjusted so that the difference in the peeling force is different. (2) As the release material, a release sheet subjected to a double-sided release treatment, a release sheet subjected to a single-side release treatment, or the like can be used, and a release agent or the like is coated on a substrate for the release material.

Examples of the base material for the release material include papers of fine paper, cellophane, and kraft paper; polyethylene terephthalate resin, polybutylene terephthalate resin, and polyethylene naphthalate Polyester resin films such as ester resins, olefin resin films such as polypropylene resins and polyethylene resins, and plastic films.

Examples of the release agent include rubber-based elastomers such as silicone resins, olefin-based resins, isoprene-based resins, and butadiene-based resins, long-chain alkyl resins, alkyd resins, and fluorine Department of resin and so on.

The thickness of the release material is not particularly limited, but is preferably 10 to 200 μm, more preferably 25 to 170 μm, and most preferably 35 to 80 μm. Examples

The present invention will be described more specifically by the following examples, but the present invention is not limited to the following examples. The physical property values in the following production examples and examples are values measured by the following methods.

<Mass average molecular weight (Mw)> 值 Values measured using a gel permeation chromatography apparatus (manufactured by Tosoh Corporation, product name "HLC-8020") under the following conditions, using standard polystyrene conversion. (Measurement conditions) • Column: "TSK guard column HXL-L", "TSK gel G2500HXL", "TSK gel G2000HXL", and "TSK gel G1000HXL" (all manufactured by Tosoh Corporation) are connected in this order. Column temperature: 40 ℃ ・ Developing solvent: tetrahydrofuran ・ Flow rate: 1.0mL / min

<Measurement of Thickness of Each Layer> 测定 The measurement was performed using a constant pressure thickness measuring device (model: "PG-02J", manufactured by TECLOCK Co., Ltd., based on standard specifications: JIS K6783, Z1702, Z1709).

<Average particle diameter (D ₅₀ ), 90% particle diameter (D ₉₀ ) of thermally expandable particles> Measured at 23 ° C. using a laser diffraction particle size distribution measuring device (for example, product name “Mastersizer 3000” manufactured by Malvern). Particle distribution of thermally expandable particles before expansion. Then, the particle size distribution of the small particles from the calculated cumulative volume frequency of 50% and 90% of the equivalent diameter of each as "average particle diameter of the thermally expandable fine particles (D _50)" and "heat-expanding particles 90% particle size (D ₉₀ ) ".

<Storage modulus E 'of thermally expandable substrate> When the measurement target is a non-adhesive thermally expandable substrate, make the thermally expandable substrate 5 mm in width by 30 mm in thickness and 200 μm in thickness, and remove the peeled material Make test samples. Using a dynamic viscoelasticity measuring device (manufactured by TA Instruments, product name "DMAQ800"), the measurement was performed under conditions of a test start temperature of 0 ° C, a test end temperature of 300 ° C, a temperature increase rate of 3 ° C / min, a vibration number of 1 Hz, and an amplitude of 20 μm The storage modulus E 'of the test sample at a specific temperature.

<Storage Shear Modulus G 'of the Adhesive Layer (X1) and the Adhesive Layer (X2)> Cut the adhesive layer (X1) and the adhesive layer (X2) into a circle with a diameter of 8 mm, and remove the release material. Lamination was performed, and a test piece having a thickness of 3 mm was used. Using a viscoelasticity measuring device (manufactured by Anton Paar, device name "MCR300"), torsional shear was performed under conditions of a test start temperature of 0 ° C, a test end temperature of 300 ° C, a temperature increase rate of 3 ° C / min, and a vibration frequency of 1Hz. Method to determine the storage shear modulus G 'of a test sample at a specific temperature.

<Probe viscosity value> After cutting the thermally expandable substrate or the expandable adhesive layer of the measurement object into squares of 10 mm on each side, it is left to stand in an environment of 23 ° C and 50% RH (relative humidity) for 24 hours. Those who removed the light release film were used as test samples. In a 23 ° C, 50% RH (relative humidity) environment, a TACKING tester (manufactured by Japan Special Instrument Co., Ltd., product name "NTS-4800") was used to determine that the light release film had been removed in accordance with JIS Z0237: 1991. The probe viscosity of the surface of the aforementioned test sample is shown. Specifically, a stainless steel probe with a diameter of 5 mm was brought into contact with the surface of the test sample at a contact load of 0.98 N / cm ² for 1 second, and then the probe was removed from the surface of the test sample at a speed of 10 mm / second. The power needed. Then, the measured value is taken as the probe viscosity value of the test sample.

The details of the adhesive resin, additives, thermally expandable particles, and release materials used in the following production examples are as follows. <Adhesive resin>-Acrylic copolymer (i): A solution containing an acrylic copolymer having a mass average molecular weight (Mw) of 600,000. The copolymer has a range from 2-ethylhexyl acrylate (2EHA) / acrylic acid 2 -A structural unit derived from a raw material monomer composed of hydroxyethyl ester (HEA) = 80.0 / 20.0 (mass ratio). Diluted solvent: ethyl acetate, solid content concentration: 40% by mass.・ Acrylic copolymer (ii): A solution containing an acrylic copolymer having a mass average molecular weight (Mw) of 600,000. The copolymer has a range from n-butyl acrylate (BA) / methyl methacrylate (MMA) / acrylic acid. A structural unit derived from a raw material monomer composed of 2-hydroxyethyl ester (HEA) / acrylic acid = 86.0 / 8.0 / 5.0 / 1.0 (mass ratio). Dilution solvent: ethyl acetate, solid content concentration: 40% by mass <additives>-isocyanate crosslinking agent (i): manufactured by Tosoh Corporation, product name "Coronate L", solid content concentration: 75% by mass. -Photopolymerization initiator (i): manufactured by BASF, product name "Irgacure 184", 1-hydroxy-cyclohexyl-phenyl-one. <Thermally expandable particles> ・ Thermally expandable particles (i): manufactured by Kureha Co., Ltd., product name "S2640", expansion start temperature (t) = 208 ° C, average particle size (D ₅₀ ) = 24 μm, 90% particle size ( D ₉₀ ) = 49 μm. <Releasing material> ・ Heavy release film: LINTEC Corporation, product name "SP-PET382150", a polyethylene terephthalate (PET) film is provided with a silicone release agent on one side The thickness of the formed release agent layer: 38 μm.・ Light release film: LINTEC Co., Ltd., product name "SP-PET381031", having a release agent layer made of a silicone-based release agent on one side of the PET film, thickness: 38 μm.

Production Example 1 (Formation of Adhesive Layer (X1)) 5.0 parts by mass of the isocyanate-based crosslinking agent (i) was added to 100 parts by mass of the solid content of the acrylic copolymer (i) as an adhesive resin ( Solid content ratio), diluted with toluene, and stirred uniformly to prepare a composition (x-1) having a solid content concentration (effective component concentration) of 25% by mass. Then, the prepared composition (x-1) was coated on the surface of the release agent layer of the heavy release film to form a coating film, and the coating film was dried at 100 ° C. for 60 seconds to form an adhesive layer having a thickness of 10 μm ( X1). The storage shear modulus G '(23) of the adhesive layer (X1) at 23 ° C was 2.5 × 10 ⁵ Pa.

Production Example 2 (Formation of Adhesive Layer (X2)) 0.8 parts by mass of the isocyanate-based crosslinking agent (i) was added to 100 parts by mass of the solid content of the acrylic copolymer (ii) as an adhesive resin ( Solid content ratio), diluted with toluene, and stirred uniformly to prepare a composition (x-2) having a solid content concentration (effective component concentration) of 25% by mass. Then, the prepared composition (x-2) was coated on the surface of the release agent layer of the light release film to form a coating film, and the coating film was dried at 100 ° C. for 60 seconds to form an adhesive layer having a thickness of 10 μm ( X2). The storage shear modulus G '(23) of the adhesive layer (X2) at 23 ° C was 9.0 × 10 ⁴ Pa.

Production Example 3 (Formation of thermally expandable substrate (Y-1)) (1) Preparation of composition (y-1) For terminal isocyanate obtained by reacting an ester-type diol with isophorone diisocyanate (IPDI) The urethane prepolymer was reacted with 2-hydroxyethyl acrylate to obtain a bifunctional acrylic urethane-based oligomer having a mass average molecular weight (Mw) of 5000. Then, 40% by mass (solid content ratio) of isobornyl acrylate (IBXA) blended into an energy ray polymerizable monomer in 40% by mass (solid content ratio) of the synthesized acrylic urethane-based oligomer. ) And 20% by mass (solid content ratio) of phenylhydroxypropyl acrylate (HPPA), further to the total amount (100 parts by mass) of the acrylic urethane-based oligomer and energy ray polymerizable monomer 2.0 parts by mass (solid content ratio) of 1-hydroxycyclohexylphenyl ketone (manufactured by BASF, product name "Irgacure 184") as a photopolymerization initiator, and 0.2 parts by mass of phthalocyanine pigment (solid (Component ratio) to prepare an energy ray-curable composition. Then, the heat-expandable particles (i) are blended into the energy ray-curable composition to prepare a solvent-free composition (y-1) containing no solvent. Furthermore, the content of the thermally expandable particles (i) was 20% by mass based on the total amount (100% by mass) of the composition (y-1).

(2) The thermally expandable substrate (Y-1) is formed on the surface of the release agent layer of the light release film, and the prepared composition (y-1) is applied to form a coating film. Then, an ultraviolet irradiation device (manufactured by EYEGRAPHICS, product name "ECS-401GX") and a high-pressure mercury lamp (manufactured by EYEGRAPHICS, product name "H04-L41") were used under the conditions of an illuminance of 160 mW / cm ² and a light amount of 500 mJ / cm ² The coating film was hardened by irradiating ultraviolet rays underneath to form a thermally expandable substrate (Y-1) having a thickness of 50 μm. In addition, the said illuminance and light quantity at the time of ultraviolet irradiation are the values measured using the illuminance and light quantity meter (made by EIT company, product name "UV Power Puck II").

Production Example 4 (Formation of thermally expandable substrate (Y-2)) (1) Synthesis of urethane prepolymer In a reaction vessel under a nitrogen atmosphere, a carbonate type having a mass average molecular weight (Mw) of 1,000 100 parts by mass of the diol (solid content ratio), so that isophorone diisocyanate (IPDI) is blended so that the equivalent ratio of the hydroxyl group of the carbonate-type diol to the isocyanate group of isophorone diisocyanate becomes 1/1. Further, 160 parts by mass of toluene was added, and the reaction was performed at 80 ° C. for more than 6 hours under stirring in a nitrogen environment until the isocyanate group concentration reached a theoretical amount. Next, a solution diluted 1.44 parts by mass (solid content ratio) of 2-hydroxyethyl methacrylate (2-HEMA) in 30 parts by mass of toluene was added, and further reacted at 80 ° C. for 6 hours until the isocyanate groups at both ends disappeared. To obtain a urethane prepolymer having a mass average molecular weight (Mw) of 29,000.

(2) Synthesis of acrylic urethane resin In a reaction vessel under a nitrogen atmosphere, 100 parts by mass (solid content ratio) of the urethane prepolymer obtained in (1) above, and methyl methacrylate were added. 117 parts by mass (MMA) (solid content ratio), 5.1 parts by mass of 2-hydroxyethyl methacrylate (2-HEMA) (solid content ratio), 1.1 parts by mass of 1-thioglycerol (solid content ratio), and 50 toluene Part by mass, the temperature was raised to 105 ° C. while stirring. Then, in the reaction vessel, a solution of 2.2 parts by mass (solid content ratio) of a radical initiator (manufactured by Japan Finechem Co., Ltd., product name "ABN-E") diluted with 210 parts by mass of toluene was maintained at 105 ° C, drip for 4 hours. After the hydrazone dripping was completed, the mixture was reacted at 105 ° C. for 6 hours to obtain a solution of an acrylic urethane resin having a mass average molecular weight (Mw) of 105,000.

(3) Formation of thermally expandable base material (Y-2) The solid component of the solution of the acrylic urethane resin obtained in the above (2) is 100 parts by mass, and the isocyanate-based crosslinking agent (i) 6.3 is blended Parts by mass (solid content ratio), 1.4 parts by mass (solid content ratio) of dioctyltin bis (2-ethylhexanoate) as a catalyst, and the thermally expandable particles (i), diluted with toluene and stirred uniformly A composition (y-2) having a solid content concentration (effective component concentration) of 30% by mass was prepared. Furthermore, the content of the thermally expandable particles (i) was 20% by mass based on the total amount (100% by mass) of the active ingredients in the obtained composition (y-2). Then, the prepared composition (y-2) was coated on the surface of the release agent layer of the light release film to form a coating film, and the coating film was dried at 100 ° C. for 120 seconds to form a thermally expandable film having a thickness of 50 μm. Substrate (Y-2).

The thermally expandable substrates (Y-1) to (Y-2) formed in Production Examples 3 to 4 were measured at 23 ° C, 100 ° C, and the expansion start temperature of the thermally expandable particles of 208 according to the methods described above, respectively. Storage modulus E 'and probe viscosity at ℃. These results are shown in Table 1.

[Table 1]

Example 1 The surfaces of the adhesive layer (X1) formed in Production Example 1 and the surface of the thermally expandable substrate (Y-1) formed in Production Example 3 were bonded to each other to remove the thermally expandable substrate (Y-1) side. On the surface of the exposed heat-expandable substrate (Y-1), a light release film was bonded to the adhesive layer (X2) formed in Production Example 2. Thus, an adhesive sheet (1) in which a light release film / adhesive layer (X2) / thermally expandable substrate (Y-1) / adhesive layer (X1) / heavy release film is laminated in this order is produced.

Example 2 制作 Except that the thermally expandable substrate (Y-1) was replaced with the thermally expandable substrate (Y-2) formed in Production Example 4, the same procedure as in Example 1 was followed to prepare a light-peelable film laminated in order. Adhesive layer (X2) / thermally expandable base material (Y-2) / adhesive layer (X1) / adhesive sheet (2) of heavy release film.

In addition, the produced adhesive sheets (1) to (2) were subjected to the following measurements. These results are shown in Table 2.

<Evaluation of the position shift of the semiconductor wafer at the time of the packaging step> Remove the light release film of the produced adhesive sheets (1) to (2), and attach it to the adhesive surface of the exposed adhesive layer (X2) as SUS board with a rigid support (thickness 1mm, size: 200mmφ). Then, the heavy release film of the adhesive sheets (1) to (2) is removed, and on the adhesive surface of the exposed adhesive layer (X1), the adhesive surface is in contact with the circuit surface of the semiconductor wafer through the necessary surface. Nine semiconductor wafers (wafer size 6.4 mm × 6.4 mm, wafer thickness 200 μm (# 2000)) were placed at regular intervals. After that, the resin film for packaging (sealing material) was laminated on the adhesive surface and the semiconductor wafer, and a vacuum heating and laminating machine ("7024HP5" manufactured by ROHM and HAAS) was used to cover the adhesive layer with the sealing material ( X1), the adhesive surface and the semiconductor wafer are cured, and the packaging material is hardened to produce a hardened package. The packaging conditions are as follows.・ Preheating temperature: 100 ° C for both the platform and diaphragm ・ Evacuation: 60 seconds ・ Dynamic pressurization mode: 30 seconds ・ Static pressurization mode: 10 seconds ・ Packaging temperature: 180 ° C 208 ° C or lower) 封装 ・ Packing time: 60 minutes

After encapsulation, the adhesive sheets (1) to (2) are heated at 240 ° C or higher for the expansion start temperature (208 ° C) of the thermally expandable particles, and the cured package is peeled from the adhesive sheets (1) to (2) to Separation, the semiconductor wafer on the surface of the semiconductor wafer side of the separated hardened package was visually and microscopically observed, and the presence or absence of the positional deviation of the semiconductor wafer was confirmed, and evaluated using the following criteria.・ A: A semiconductor wafer with a position deviation of 25 μm or more before packaging is not seen.・ F: A semiconductor wafer with a position shift of 25 μm or more before packaging is seen.

<Evaluation of the flatness of the surface of the semiconductor wafer side after the packaging step> Use the adhesive sheets (1) to (2) to produce a hardened package by the same procedure as in the above-mentioned "position evaluation of the semiconductor wafer during the packaging step". The body is separated from the adhesive sheet. The surface of each of the produced cured packages on the semiconductor wafer side was measured using a contact surface roughness meter ("SV3000" manufactured by Mitutoyo Corporation), and evaluated in accordance with the following criteria.・ A: No place where a step of 2 μm or more occurs.・ F: Where a step of 2 μm or more is seen.

<Measurement of the adhesive force of the adhesive sheet before and after heating> Remove the light release film on the adhesive layer (X2) side of the produced adhesive sheets (1) to (2), and expose the adhesive layer (X2) On the adhesive surface, a polyethylene terephthalate (PET) film (manufactured by Toyobo Co., Ltd., product name "Cosmoshine A4100") with a thickness of 50 μm was laminated to form a substrate-attached adhesive sheet. Then, the heavy release film on the adhesive layer (X1) side of the adhesive sheets (1) to (2) was also removed, and the adhesive surface of the exposed adhesive layer (X1) was attached to the stainless steel plate to be adhered. (Grinding SUS304 360), the test sample shall be left to stand for 24 hours under the environment of 23 ° C and 50% RH (relative humidity). Then, using the above test sample, at 23 ° C and 50% RH (relative humidity), in accordance with JIS Z0237: 2000, the 180 ° tearing method was used to measure the temperature at 23 ° C at a tensile speed of 300 mm / min. Adhesion. In addition, the above-mentioned test sample was heated on a hot plate at 240 ° C. above the expansion expansion temperature of thermally expandable particles (208 ° C.) for 3 minutes, and left to stand in a standard environment (23 ° C., 50% RH (relative humidity)). After 60 minutes, in accordance with JIS Z0237: 2000, the 180 ° tearing method was used to measure the adhesive force after heating at a stretching speed of 300 mm / min or more at a temperature higher than the expansion start temperature. Furthermore, if it is difficult to measure the adhesive force when it cannot be attached to the stainless steel plate to be adhered, it is regarded as "unmeasureable", and its adhesive force is regarded as 0 (N / 25 mm).

<Evaluation of selective peelability of individual wafers> Remove the light release film on the adhesive layer (X2) side of the prepared adhesive sheets (1) to (2), and expose the adhesive layer ( X2) On the adhesive surface, a vinyl chloride (PVC) film with a thickness of 60 μm was laminated to form an adhesive sheet with a substrate. Then, the heavy release film on the adhesive layer (X1) side of the adhesive sheets (1) to (2) was also removed, and a silicon wafer (6 inches) was attached to the adhesive surface of the exposed adhesive layer (X1). Diameter, thickness 350 μm), the adhesive sheets (1) to (2) were mounted on a ring frame (manufactured by SUS), and installed in a cutting device (manufactured by DISCO Corporation, product name "DFD651") under the following conditions Dicing, to obtain a sliced wafer as a plurality of processing inspection objects.・ Cutter: 27HEEE by DISCO Corporation Number of blade rotations: 50,000 rpm Cutting speed: 10mm / sec. Cutting depth: Cut from the base film from the interface of the adhesive layer to a depth of 20μm. Cutting size: 2.5mm´ 2.5mnn Next, using an expansion jig (manufactured by NEC Machinery Co., Ltd., product name "CSP-100VX"), an adhesive sheet in the state of a wafer is attached to the adhesive surface of the adhesive layer (X1). 5mm was torn off at a speed of 300mm / min. Next, as a heating section, a heating means provided with a 2.5 mm square and 1 mm thick metal plate (made of SUS) and a thermally conductive rubber sheet (2.5 mm square, 1 mm in thickness) at the front end of the electric heating heater was prepared. The part (frontmost part) was heated by an electric heater so that the temperature of 240 degreeC might become 240 degreeC. Among the plurality of slicing wafers, arbitrarily select the slicing wafers to be peeled off, and heating the portion of the sticking sheet to which the selected slicing wafers are attached, thereby reducing the adhesive force. It is confirmed whether the selected individual wafers can be peeled from the adhesive sheet by the suction nozzle. Then, an impact was forcibly applied to the individual wafers attached to the non-heated portion of the adhesive sheet, and the presence or absence of the individual wafers was confirmed. The evaluation criteria are as follows.・ A: The selected piece of wafer can be peeled off from the adhesive sheet by the suction nozzle, and the piece of wafer attached to the non-heated part of the adhesive sheet does not come off.・ F: The selected individual wafer cannot be peeled from the adhesive sheet by the suction nozzle. Or, although it can be peeled off, it is seen that the individual wafers attached to the non-heated portion of the adhesive sheet come off.

[Table 2] (*): Since the test sample cannot be attached to the adherend (SUS board), the adhesion cannot be measured.

According to Table 2, if the manufacturing methods of the adhesive sheets (1) and (2) using Examples 1 and 2 are used, the positional deviation of the semiconductor wafer during the packaging step cannot be seen, and the semiconductor wafer side after the packaging step cannot be seen. The surface is also flat. In addition, although the adhesive sheets (1) and (2) had good adhesive force before heating, the adhesive force was reduced to an unmeasureable level after heating above the expansion initiation temperature. As a result, it was confirmed that during peeling, a little The force easily peels off.

In addition, it is clear from Table 2 that by using the adhesive sheets (1) and (2) of Examples 1 and 2, it is possible to heat the adhesive sheet while maintaining the adhered state of the non-selected individual wafers to the adhesive sheet. Only selected wafers are stripped.

1a, 1b ‧‧‧ single-sided adhesive sheet

2a, 2b ‧‧‧ double-sided adhesive sheet

7‧‧‧ Objects for processing and inspection

7a‧‧‧ should be peeled off

11‧‧‧ Thermally expandable substrate

121‧‧‧Adhesive layer (X1)

121a‧‧‧ Adhesive surface of the adhesive layer (X1)

122‧‧‧Adhesive layer (X2)

122a‧‧‧ Adhesive surface of the adhesive layer (X2)

131, 132‧‧‧ peeling material

14‧‧‧ rigid support

15‧‧‧ adsorption nozzle

20‧‧‧Frame components

21‧‧‧ opening of frame member

30‧‧‧ in the adhesive surface of the adhesive layer (X1), the peripheral portion and the gap of the semiconductor wafer

40‧‧‧Packaging material

41‧‧‧hardened packaging material

50‧‧‧ Package

50a‧‧‧ after a chip package

60‧‧‧ fixed means

80‧‧‧ heating means

81‧‧‧Heating section

CP‧‧‧Semiconductor wafer

W1‧‧‧Circuit Surface

FIG. 1 is a cross-sectional model view showing an example of a configuration of a single-sided adhesive sheet used in the method for thermally peeling a processing inspection object according to the present invention. FIG. 2 is a cross-sectional model diagram showing an example of the configuration of a double-sided adhesive sheet used in the method for heat-peeling a processing inspection object according to the present invention. FIG. 3 is a model diagram showing an example of a state where a single-sided adhesive sheet is used in step (I) of the method for heating and peeling an object to be processed and inspected according to the present invention. FIG. 4 is a model diagram showing an example of a state of using a double-sided adhesive sheet in step (I) of the method for heating and peeling an object to be processed and inspected according to the present invention. FIG. 5 is a model diagram showing an example of a state in which a single-sided adhesive sheet is used in step (II) of the method for heating and peeling a processing inspection object according to the present invention. FIG. 6 is a model diagram showing an example of a state of using a double-sided adhesive sheet in step (II) of the method for heating and peeling an object to be processed and inspected according to the present invention. FIG. 7 is a cross-sectional model diagram showing an example of steps (I-A1) to (I-A3) in one aspect of the method for heating and peeling a processing inspection object according to the present invention. FIG. 8 is a cross-sectional model diagram showing an example of steps (I-B1) to (I-B3) in one aspect of the method for heating and peeling a processing inspection object according to the present invention.

Claims (15)

A heat-peeling method for processing an inspection object, which is characterized by having the following steps (I) and (II), and (1): an adhesive sheet on a non-adhesive heat-expandable substrate and an adhesive layer (X1) A step of attaching a plurality of objects to be inspected for processing on the adhesive surface of the adhesive layer (X1), the non-adhesive heat-expandable substrate containing a resin and heat-expandable particles, step (II): a part of the aforementioned heat-expandable substrate A step of heating the thermally expandable particles to a temperature at which the thermally expandable particles swell, and selectively peeling off a part of the plurality of processing inspection objects. The method as claimed in claim 1, wherein the aforementioned step (I) has the following steps (I-1) to (I-2), (i) Step (I-1): on the adhesive surface of the adhesive layer (X1) of the aforementioned adhesive sheet The step of attaching a processing inspection object before slicing, ， Step (I-2): a step of slicing the processing inspection object before the slicing on the adhesive surface. The method according to claim 1 or 2, wherein the adhesive sheet is a double-sided adhesive sheet having an adhesive layer (X2) on the opposite side of the side of the thermally expandable substrate laminated with the adhesive layer (X1), which It is used by attaching a rigid support to the adhesive surface of the adhesive layer (X2) of the double-sided adhesive sheet. The method as claimed in claim 3, wherein step (I) has the following steps (I-A1) to (I-A3), and (1) Step (I-A1): placing a plurality of semiconductor wafers between adjacent semiconductor wafers A step of placing the gap on the adhesive surface of the adhesive layer (X1) at the same time, a step (I-A2): covering the adhesive surface of the plurality of semiconductor wafers and the peripheral portions of the plurality of semiconductor wafers with a packaging material so that A step of hardening the packaging material to obtain a package in which the plurality of semiconductor wafers are packaged in the hardened packaging material; (1) Step (I-A3): a step of singulating the package into individual semiconductor wafer units. The method according to claim 1 or 2, wherein the aforementioned adhesive sheet is used by attaching a frame member having an opening formed on an adhesive surface of the adhesive layer (X1). The method as claimed in claim 5, wherein step (I) has the following steps (I-B1) to (I-B3), and (1) Step (I-B1): placing a plurality of semiconductor wafers between the adjacent semiconductor wafers A step of placing the gap on the adhesive surface of the adhesive layer (X1) exposed at the opening of the frame member at the same time, the step (I-B2): covering the plurality of semiconductor wafers and the plurality of semiconductors with a packaging material A step of hardening the packaging material to obtain a package in which the plurality of semiconductor wafers are packaged in the hardened packaging material on the adhesive surface of the peripheral portion of the wafer. (1) Step (I-B3): The package is packaged in units of the semiconductor wafer. A piece of step. The method according to any one of claims 1 to 6, wherein the heating in step (II) is performed on the side of the thermally expandable substrate opposite to the side where the adhesive layer (X1) is laminated. The method according to any one of claims 1 to 7, wherein the thermally expandable base material satisfies the following requirements (1), • requirements (1): The storage modulus E '(23) at 23 ° C is 1.0 × 10 ⁶ Pa or more. The method according to any one of claims 1 to 8, wherein the aforementioned thermally expandable substrate satisfies the following requirements (2), • requirements (2): The storage modulus E '(100) at 100 ° C is 2.0 × 10 ⁵ Pa or more. The method according to any one of claims 1 to 9, wherein the expansion start temperature (t) of the thermally expandable particles is 120 to 250 ° C, and the thermally expandable base material satisfies the following requirements (3), and the requirements (3) : The storage modulus E '(t) at the expansion start temperature (t) is 1.0 × 10 ⁷ Pa or less. The method according to any one of claims 1 to 10, wherein the storage shear modulus G '(23) of the adhesive layer (X1) at 23 ° C is 1.0 × 10 ⁴ to 1.0 × 10 ⁸ Pa. The method according to any one of claims 1 to 11, wherein the ratio of the thickness of the aforementioned thermally expandable substrate to the thickness of the adhesive layer (X1) at 23 ° C (thermally expandable substrate / adhesive layer (X1)) is 0.2 or more. The method according to any one of claims 1 to 12, wherein the thickness of the aforementioned thermally expandable substrate at 23 ° C is 10 to 1000 µm, and the thickness of the adhesive layer (X1) is 1 to 60 µm. The method according to any one of claims 1 to 13, wherein the probe viscosity value on the surface of the thermally expandable substrate is less than 50 mN / 5 mmφ. The method according to any one of claims 1 to 14, wherein the average particle diameter of the thermally expandable particles before expansion at 23 ° C is 3 to 100 µm.