Composite sheet roll for forming a protective film

Abstract

The present invention provides a composite sheet roll for forming a protective film, which is a composite sheet roll for forming a protective film formed by winding a composite sheet for forming a protective film into a roll shape. The composite sheet for forming a protective film includes a support sheet, a film for forming a protective film provided on one surface of the support sheet, and a release film provided on the surface of the film for forming a protective film opposite to the support sheet side, and the composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface in the radial direction of the roll.

Description

Technical Field

[0001] The present invention relates to a composite sheet roll for forming a protective film.

[0002] This application claims priority based on Japanese Patent Application No. 2019-149737 filed in Japan on August 19, 2019, and incorporates its content herein. Background Art

[0003] In recent years, semiconductor devices have been manufactured using an installation method called the face-down method. In the face-down method, a semiconductor chip having protruding electrodes such as bumps on a circuit formation surface is used, and the electrodes are bonded to a substrate. Therefore, the surface (back surface) of the semiconductor chip opposite to the circuit formation surface may be exposed.

[0004] A resin film containing an organic material as a protective film is formed on the back surface of the exposed semiconductor chip, and it is sometimes incorporated into a semiconductor device as a semiconductor chip with a protective film. The protective film is used to prevent cracks from occurring in the semiconductor chip during the dicing process or after packaging.

[0005] To form such a protective film, for example, a composite sheet for forming a protective film is used, which includes a support sheet and further includes a protective film-forming film for forming a protective film on one surface of the support sheet.

[0006] The protective film-forming film can function as a protective film by being cured, or can also function as a protective film in an uncured state. For example, when dicing a semiconductor wafer having a protective film-forming film or a protective film on the back surface into semiconductor chips, the support sheet can be used as a dicing sheet to fix the semiconductor wafer. In addition, it can also be used in the case of cutting the protective film-forming film or the protective film in a state where it is already attached to the semiconductor wafer or the semiconductor chip.

[0007] When manufacturing a semiconductor chip with a protective film, for example, a laminate having the following structure may be produced: a structure in which a composite sheet for forming a protective film is attached to the back surface of a semiconductor chip group in a state where a plurality of semiconductor chips are neatly arranged and fixed; or a structure in which a composite sheet for forming a protective film is attached to the back surface of a semiconductor wafer in a state where it can be easily divided into semiconductor chips. The semiconductor chip group may have an undivided area where a part of the semiconductor wafer is not divided. A method for manufacturing such a semiconductor chip group or semiconductor wafer will be described in detail later. At this time, the composite sheet for forming a protective film is attached to the back surface of the semiconductor chip group or the semiconductor wafer through the protective film-forming film therein.

[0008] After producing the laminate, a semiconductor chip with a protective film can be manufactured in the order shown below.

[0009] That is, first, the protective film-forming film or the protective film in the protective film-forming composite sheet is cut by performing so-called cool expand, in which the protective film-forming composite sheet in the laminate is cooled while being stretched in a direction parallel to its surface. That is, when the protective film-forming film in the protective film-forming composite sheet is curable, the curing timing is arbitrary. Usually, the protective film-forming composite sheet in the laminate is placed on a stage (so-called expand stage) to perform cool expand. By cool expand, the protective film-forming film or the protective film attached to the semiconductor chip is cut at a position along the outer periphery of the semiconductor chip. On the other hand, when the protective film-forming film or the protective film is attached to the undivided region or the semiconductor wafer, it is divided into semiconductor chips at these undivided regions or semiconductor wafers, and at the same time, the protective film-forming film or the protective film is cut along the division position.

[0010] Next, the semiconductor chip having the cut protective film-forming film or the protective film on the back surface is separated from the support sheet and picked up.

[0011] When the protective film-forming film is curable, the curing of the protective film-forming film (i.e., the formation of the protective film) can be performed at an arbitrary timing as needed. When the protective film-forming film is non-curable, the protective film-forming film attached to the back surface of the semiconductor chip group or the semiconductor wafer is regarded as the protective film.

[0012] In the above manner, a semiconductor chip with a protective film composed of a semiconductor chip and a protective film provided on the back surface of the semiconductor chip can be obtained.

[0013] The protective film-forming composite sheet is usually stored in a state where a release film is provided on the outermost layer on the protective film-forming film side. Further, sometimes the protective film-forming composite sheet having such a release film is wound into a roll shape for storage. Summary of the Invention

[0014] Technical Problem to be Solved by the Invention

[0015] However, if the wound protective film-forming composite sheet is unrolled and then used for the manufacture of the above-mentioned semiconductor chip with a protective film, during cool expand, the semiconductor chip having the protective film-forming film or the protective film on the back surface will peel off and fly off from the support sheet, and there is a technical problem of so-called chip scattering. Moreover, once such chip scattering occurs, chip scattering will also occur when using the same expand stage and then performing cool expand later, and there is a technical problem of repeated chip scattering.

[0016] An object of the present invention is to provide a composite sheet roll for forming a protective film, which is formed by winding a composite sheet for forming a protective film having a support sheet, a film for forming a protective film, and a release film. When the composite sheet for forming a protective film is unwound and cold-expanded, chip scattering can be suppressed.

[0017] Technical means for solving technical problems

[0018] The present invention provides a composite sheet roll for forming a protective film, which is a composite sheet roll for forming a protective film formed by winding a composite sheet for forming a protective film into a roll shape. Among them, the composite sheet for forming a protective film has a support sheet, a film for forming a protective film provided on one surface of the support sheet, and a release film provided on the surface of the film for forming a protective film opposite to the support sheet side. The composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface in the radial direction of the roll.

[0019] In the composite sheet roll for forming a protective film of the present invention, the film for forming a protective film may be thermosetting or energy ray curable.

[0020] In the composite sheet roll for forming a protective film of the present invention, the support sheet has a base material and an adhesive layer provided on one surface of the base material, and the adhesive layer can be disposed between the base material and the film for forming a protective film.

[0021] In the composite sheet roll for forming a protective film of the present invention, the adhesive layer may be energy ray curable.

[0022] In the composite sheet roll for forming a protective film of the present invention, when the static voltage of the outermost surface on the release film side of the composite sheet for forming a protective film is measured immediately after unwinding the composite sheet for forming a protective film from the composite sheet roll for forming a protective film, the static voltage may be 3.0 kV or less.

[0023] Advantages of the invention

[0024] According to the present invention, a composite sheet roll for forming a protective film can be provided, which is formed by winding a composite sheet for forming a protective film having a support sheet, a film for forming a protective film, and a release film into a roll shape. When the composite sheet for forming a protective film is unwound and cold-expanded, chip scattering can be suppressed. Description of the drawings

[0025] Figure 1 It is a cross-sectional view schematically showing an example of a composite sheet for forming a protective film.

[0026] Figure 2 It is a cross-sectional view schematically showing another example of a composite sheet for forming a protective film.

[0027] Figure 3 An enlarged cross-sectional view for expanding and schematically showing an example of a composite sheet roll for forming a protective film according to an embodiment of the present invention.

[0028] Figure 4 A perspective view for schematically showing an example of a state where a composite sheet for forming a protective film is being wound into a roll shape, or a state where the composite sheet for forming a protective film is being unwound from a composite sheet roll for forming a protective film according to an embodiment of the present invention.

[0029] Explanation of reference numerals

[0030] 101, 102: Composite sheet for forming a protective film; 102R: Composite sheet roll for forming a protective film; 10: Support sheet; 10a: One surface of the support sheet; 11: Substrate; 11a: One surface of the substrate; 12: Adhesive layer; 13, 23: Film for forming a protective film; 13a, 23a: Surfaces of the film for forming a protective film opposite to the support sheet side; 15: Release film; 15a: Surface of the release film opposite to the film for forming a protective film side. Detailed description of the embodiments

[0031] ◇Composite sheet roll for forming a protective film

[0032] A composite sheet roll for forming a protective film according to an embodiment of the present invention (in this specification, sometimes simply abbreviated as "roll") is constituted by winding a composite sheet for forming a protective film into a roll shape. The composite sheet for forming a protective film includes a support sheet, a film for forming a protective film provided on one surface of the support sheet, and a release film provided on a surface of the film for forming a protective film opposite to the support sheet side. The composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface in the radial direction of the roll. In other words, in the composite sheet roll for forming a protective film of the present embodiment, the composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the support sheet side of the composite sheet for forming a protective film is the innermost surface in the radial direction of the roll.

[0033] Hereinafter, in this specification, unless otherwise specified, both "outermost" and "innermost" refer to positions in the radial direction of the roll.

[0034] The film for forming a protective film can form a protective film and can be curable or non-curable as described later.

[0035] The curable film for forming a protective film can be any one of thermosetting and energy ray curable, or can have both thermosetting and energy ray curable properties at the same time.

[0036] In this specification, "energy ray" refers to an energy ray having an energy quantum in an electromagnetic wave or a charged particle beam, and examples thereof include ultraviolet rays, radiation, electron beams, etc. Ultraviolet rays can be irradiated by using, for example, a high-pressure mercury lamp, a fusion lamp, a xenon lamp, a black light lamp, or an LED lamp as an ultraviolet source. Electron beams can be irradiated by using electron beams generated by electron beam accelerators, etc.

[0037] In the present specification, “energy ray-curable” means a property of being cured by irradiation with energy rays, and “non-energy ray-curable” means a property of not being cured even by irradiation with energy rays.

[0038] In the present specification, "non-curable" means a property that a material does not cure even by any means such as heating or irradiation with energy rays.

[0039] In the previous composite sheet roll for forming a protective film, the exposed surface of the support sheet in the composite sheet for forming a protective film is the outermost surface. The inventors of the present application have found that in the process of unwinding the composite sheet for forming a protective film from the previous composite sheet roll for forming a protective film and using it to manufacture semiconductor chips with protective films, foreign matter is often attached to the support sheet. If this state is not corrected and the semiconductor chips with protective films are continued to be manufactured, foreign matter will be sandwiched between the table for placing the object and the support sheet during the cutting of semiconductor wafers, cold expansion of the protective film forming film or the protective film, etc., which will cause the chips to fly. It is speculated that the reason why foreign matter is easy to adhere to the support sheet is that during the storage of the composite sheet roll for forming a protective film, since the support sheet as the outermost layer is exposed to the air, foreign matter is easy to adhere to the exposed surface of the support sheet due to static electricity, etc.

[0040] In contrast, in the composite sheet roll for forming a protective film of the present embodiment, as described above, the outermost surface is not the support sheet side of the composite sheet for forming a protective film, but the outermost surface of the stripping film side. Therefore, during the storage of the composite sheet roll for forming a protective film, foreign matter is not easy to adhere to the outermost surface of the support sheet side, which is the innermost surface, and even if foreign matter adheres to the outermost surface of the stripping film side, when the composite sheet for forming a protective film unwound from the roll is used, the stripping film is removed. Therefore, foreign matter can be prevented from being sandwiched between the stage and the support sheet, and as a result, the chips can be prevented from flying.

[0041] In this specification, in any case, the surface of a semiconductor wafer or a semiconductor chip opposite to the circuit formation surface is referred to as a "back surface".

[0042] In addition, a semiconductor chip having a protective film on its back surface is sometimes referred to as a "semiconductor chip with a protective film", and a semiconductor chip having a film for protective film formation on its back surface is sometimes referred to as a "semiconductor chip with a protective film formation film".

[0043] In addition, a structure in which a plurality of semiconductor chips are neatly arranged and fixed is sometimes referred to as a "semiconductor chip group".

[0044] In addition, a structure in which a plurality of semiconductor chips with a film for forming a protective film are neatly arranged and fixed is sometimes referred to as a "semiconductor chip group with a film for forming a protective film".

[0045] In addition, a structure in which a single composite sheet for forming a protective film is provided on the back surface of each semiconductor chip in a semiconductor chip group is sometimes referred to as a "semiconductor chip group with a composite sheet for forming a protective film".

[0046] Hereinafter, with reference to the drawings, the composite sheet roll for forming a protective film according to the present embodiment will be described in detail.

[0047] In addition, in order to more easily understand the features of the present invention, for convenience, sometimes important portions of the drawings used in the following description are enlarged and shown, and the dimensional ratios of the respective components are not necessarily the same as the actual ones.

[0048] First, the composite sheet for forming a protective film, which is an object to be wound into a roll, will be described.

[0049] Figure 1 FIG. is a cross-sectional view schematically showing an example of the composite sheet for forming a protective film.

[0050] The composite sheet 101 for forming a protective film shown here includes a support sheet 10, a film 13 for forming a protective film provided on one surface 10a of the support sheet 10, and a release film 15 provided on a surface 13a of the film 13 for forming a protective film, which is opposite to the side of the support sheet 10.

[0051] The support sheet 10 includes a base material 11 and an adhesive layer 12 provided on one surface 11a of the base material 11. In the composite sheet 101 for forming a protective film, the adhesive layer 12 is disposed between the base material 11 and the film 13 for forming a protective film.

[0052] That is, the composite sheet 101 for forming a protective film is formed by laminating the base material 11, the adhesive layer 12, the film 13 for forming a protective film, and the release film 15 in this order along their thickness directions.

[0053] The surface 10a of the support sheet 10 is the same as the surface 12a of the adhesive layer 12, which is opposite to the side of the base material 11.

[0054] The surface 15a of the release film 15 on the side opposite to the side of the film 13 for forming a protective film, and the surface 10b of the support sheet 10 on the side opposite to the surface 10a are both the outermost surfaces of the composite sheet 101 for forming a protective film. The surface 10b of the support sheet 10 is the same as the surface 11b of the base material 11 on the side opposite to the surface 11a.

[0055] The composite sheet 101 for forming a protective film further has a jig adhesive layer 16 on the film 13 for forming a protective film.

[0056] In the composite sheet 101 for forming a protective film, an adhesive layer 12 is laminated on the entire surface or almost the entire surface of the surface 11a of the base material 11, a film 13 for forming a protective film is laminated on the entire surface or almost the entire surface of the surface 12a of the adhesive layer 12, and a jig adhesive layer 16 is laminated on a part of the surface 13a of the film 13 for forming a protective film, that is, in a region near the peripheral portion. Further, a release film 15 is laminated on the region of the surface 13a of the film 13 for forming a protective film where the jig adhesive layer 16 is not laminated, and on the surface 16a of the jig adhesive layer 16 on the side opposite to the side of the film 13 for forming a protective film.

[0057] Figure 1 In [description], the symbol 13b represents the surface of the film 13 for forming a protective film on the side opposite to the surface 13a.

[0058] The jig adhesive layer 16 is used to fix the composite sheet 101 for forming a protective film to a jig such as an annular frame.

[0059] The jig adhesive layer 16 can, for example, have a single-layer structure containing an adhesive component, or can have a multi-layer structure in which layers containing an adhesive component are laminated on both surfaces of a sheet as a core material.

[0060] Further, the composite sheet 101 for forming a protective film has a cut 17.

[0061] When looking down on the composite sheet 101 for forming a protective film from above in the direction from the support sheet 10 side, the cut 17 is formed in such a way as to divide the first laminated sheet 1011, which is a laminate of the support sheet 10 and the film 13 for forming a protective film, into a target shape such as a circle. Further, in the thickness direction of the composite sheet 101 for forming a protective film, the cut 17 is continuously formed from the surface 10b of the support sheet 10 to the surface 16a of the jig adhesive layer 16. By having the cut 17, after removing the release film 15, the region of the composite sheet 101 for forming a protective film closer to the center than the cut 17 can be used.

[0062] In addition, the cut 17 has an arbitrary configuration, and the composite sheet 101 for forming a protective film may not have the cut 17.

[0063] Regarding the composite sheet 101 for forming a protective film, for example, each composite sheet 101 for forming a protective film may have a plurality of second laminated sheets 1012 that are laminated bodies of a support sheet 10, a film 13 for forming a protective film, and a jig adhesive layer 16. The surface 13a of the film 13 for forming a protective film and the surface 16a of the jig adhesive layer 16 in the plurality of second laminated sheets 1012 are laminated on a single release film 15.

[0064] Thus, when the composite sheet 101 for forming a protective film has a plurality of second laminated sheets 1012, for example, the release film 15 may be a long rectangle, and the plurality of second laminated sheets 1012 are arranged along the long side direction of the release film 15.

[0065] The composite sheet 101 for forming a protective film is used as follows: in a state where the release film 15 is removed, the back surface of a semiconductor wafer (not shown) is attached to the surface 13a of the film 13 for forming a protective film. Further, the surface 16a of the jig adhesive layer 16 is attached to a jig such as an annular frame.

[0066] Figure 2 It is a cross-sectional view schematically showing other examples of the composite sheet for forming a protective film.

[0067] In addition, in Figure 2 In the subsequent figures, for the constituent elements that are the same as those shown in the figures that have already been described, the same reference numerals as those in the figures that have already been described are marked, and their detailed descriptions are omitted.

[0068] The composite sheet 102 for forming a protective film shown here is the same as the Figure 1 composite sheet 101 for forming a protective film shown, except that the shape of the film for forming a protective film is different and it does not have the jig adhesive layer 16.

[0069] In the composite sheet 102 for forming a protective film, an adhesive layer 12 is laminated on the entire surface or almost the entire surface of the surface 11a of the base material 11. A film 23 for forming a protective film is laminated on a part of the surface 12a of the adhesive layer 12, that is, in a region near the center (in other words, a region except near the peripheral portion). And a release film 15 is laminated on the entire surface or almost the entire surface of the surface 23a of the film 23 for forming a protective film and on the region of the surface 12a of the adhesive layer 12 where the film 23 for forming a protective film is not laminated (in other words, the region near the peripheral portion).

[0070] Figure 2 In, the symbol 23b represents the surface of the film 23 for forming a protective film that is opposite to the surface 23a.

[0071] In the protective film forming composite sheet 102 , the surface area of the surface 23 a of the protective film forming film 23 is smaller than the surface area of the surface 12 a of the pressure-sensitive adhesive layer 12 .

[0072] The cutout 27 in the composite sheet 102 for forming a protective film is the same as the cutout 17 in the composite sheet 101 for forming a protective film, except that the region where the cutout 27 is formed is located only on the supporting sheet 10 .

[0073] Regarding the composite sheet 102 for forming a protective film, for example, each composite sheet 102 for forming a protective film can have a first laminated sheet 1021 which is a laminate of multiple supporting sheets 10 and protective film forming films 23, and the surface 23a of the protective film forming film 23 and the surface 12a of the adhesive layer 12 in the multiple first laminated sheets 1021 are laminated on a peeling film 15.

[0074] In this way, when the composite sheet 102 for forming a protective film has a plurality of first laminate sheets 1021 , for example, the release film 15 may be in a long rectangular shape, and the plurality of first laminate sheets 1021 may be arranged along the long side direction of the release film 15 .

[0075] The composite sheet for forming a protective film is not limited to Figures 1 - 2 The protective film forming composite sheet shown in the figure may be changed or deleted without impairing the effect of the present invention. Figures 1 - 2 The composite sheet for forming a protective film shown may be a composite sheet composed of a part of the composite sheet for forming a protective film, or may be a composite sheet in which other structures are added to the composite sheet for forming a protective film described above.

[0076] Herein, a supporting sheet having only a base material and an adhesive layer is shown as a supporting sheet, but the supporting sheet may also have other layers (such as an intermediate layer) or may only be composed of a base material. Such other supporting sheets will be described in detail later.

[0077] Preferred composite sheets and composite sheet rolls for forming a protective film include composite sheets and composite sheet rolls for forming a protective film, wherein a supporting sheet comprises a substrate and an adhesive layer provided on one surface of the substrate, and the adhesive layer is arranged between the substrate and the protective film forming film.

[0078] So far, only the composite sheet for forming a protective film having an adhesive layer for a jig has been shown. Figure 1 The protective film forming composite sheet 101 shown in FIG. Figure 2 The protective film forming composite sheet 102 shown in the figure may include a protective film forming film 23 on the surface 12a of the adhesive layer 12 in the region where the protective film forming film 23 is not laminated. Figure 1 The same adhesive layer for the clamp as shown in the above. At this time, the incision 27 isFigure 1 Similar to the cut 17 in the composite sheet 101 for forming a protective film shown, it can be formed continuously from the surface 10b of the support sheet 10 and penetrate through the adhesive layer for the jig. However, this is only an example of other composite sheets for forming a protective film having an adhesive layer for the jig.

[0079] So far, as the components constituting the composite sheet for forming a protective film, a base material, an adhesive layer, an intermediate layer, a film for forming a protective film, and a release film have been shown. However, the composite sheet for forming a protective film may also have other layers that do not belong to any of them.

[0080] When the composite sheet for forming a protective film has the other layer, its arrangement position is not particularly limited.

[0081] In the composite sheet for forming a protective film, the size and shape of each layer can be arbitrarily selected according to the purpose.

[0082] Next, the composite sheet roll for forming a protective film of the present embodiment using the composite sheet for forming a protective film will be described.

[0083] Figure 3 An enlarged cross-sectional view for expanding and schematically showing an example of the composite sheet roll for forming a protective film of the present embodiment, Figure 4 A perspective view for schematically showing a state where the composite sheet for forming a protective film is being wound into a roll shape, or a state where the composite sheet for forming a protective film is being unwound from the composite sheet roll for forming a protective film of the present embodiment. Here, the roll when using Figure 2 the composite sheet 102 for forming a protective film shown will be described.

[0084] It can be Figure 2 regarded as Figure 4 a cross-sectional view taken along the line I-I of the composite sheet 102 for forming a protective film shown. In addition, it can be Figure 3 regarded as Figure 4 a cross-sectional view taken along the line II-II of the composite sheet roll 102R for forming a protective film shown.

[0085] The composite sheet roll 102R for forming a protective film shown here is configured by winding the composite sheet 102 for forming a protective film into a roll shape such that the outermost surface on the release film 15 side of the composite sheet 102 for forming a protective film is the outermost surface. More specifically, the surface 15a of the release film 15 is the outermost surface. That is, in the composite sheet roll 102R for forming a protective film, the outermost surface on the support sheet 10 side of the composite sheet 102 for forming a protective film is the innermost surface. More specifically, the surface 10b of the support sheet 10 is the innermost surface.

[0086] By winding the composite sheet 102 for forming a protective film in this manner, in the radial direction of the roll 102R ( Figure 3 the direction of the arrow X in the figure), the laminated units composed of the support sheet 10, the film 23 for forming a protective film, and the release film 15 are repeatedly arranged in the same orientation from the inside to the outside of the roll 102R. And, in all of the said laminated units, the film 23 for forming a protective film and the release film 15 are located on the outside of the radial direction X compared with the support sheet 10. That is, the roll 102R is configured such that the release film 15 is on the outside and the support sheet 10 is on the inside when wound.

[0087] By winding the composite sheet 102 for forming a protective film in this manner, when performing cold expansion using the composite sheet 102 unwound from the composite sheet roll 102R for forming a protective film, chip scattering can be suppressed. As described above, the reason is that foreign matter is not easily attached to the surface 10b of the support sheet 10, and even if foreign matter is attached to the surface 15a of the release film 15, the release film 15 will be removed when using the composite sheet 102 for forming a protective film.

[0088] In addition, since foreign matter can be suppressed from attaching to the surface 10b of the support sheet 10 in this way, foreign matter can also be suppressed from attaching to the expansion table, so that chip scattering can also be suppressed from occurring repeatedly when performing cold expansion subsequently.

[0089] The composite sheet roll for forming a protective film of the present embodiment is not limited to Figures 3 - 4 the composite sheet roll for forming a protective film shown in the figure, and within the range that does not impair the effects of the present invention, it may be a composite sheet roll in which a part of the composite sheet for forming a protective film shown in Figures 3 - 4 the figure is changed or deleted, or it may be a composite sheet roll in which other components are further added on the basis of the composite sheet roll for forming a protective film described above. More specifically, as follows.

[0090] So far, the composite sheet roll for forming a protective film when using the composite sheet 102 for forming a protective film shown in Figure 2 the figure has been described, but the roll of the present embodiment may also use, for example, Figure 1 other composite sheets for forming a protective film such as the composite sheet 101 for forming a protective film shown in the figure.

[0091] Even when using other composite sheets for forming a protective film, by winding them into a roll shape such that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface, the outermost layer on the release film side is wound on the outside, and the outermost layer on the support sheet side is wound on the inside, the same effects as those of the composite sheet roll 102R for forming a protective film will be achieved.

[0092] When the pressure-sensitive adhesive forming composite sheet is unwound from the pressure-sensitive adhesive forming composite sheet roll and the static voltage on the outermost surface on the release film side of the pressure-sensitive adhesive forming composite sheet is immediately measured, the static voltage can be 3.0 kV or less. The outermost surface on the support sheet side of the pressure-sensitive adhesive forming composite sheet that has just been unwound from the pressure-sensitive adhesive forming composite sheet roll also tends to have a low static voltage. In this case, when the pressure-sensitive adhesive forming composite sheet is cold-expanded, the effect of suppressing chip scattering tends to be higher.

[0093] In addition, in the pressure-sensitive adhesive forming composite sheet, when the outermost layer on the release film side is the release film, the "outermost surface on the release film side" refers to the "exposed surface of the release film", and when the outermost layer on the support sheet side is the support sheet, the "outermost surface on the support sheet side" refers to the "exposed surface of the support sheet".

[0094] From the perspective of making the above effects higher, in the pressure-sensitive adhesive forming composite sheet roll, the static voltage can be in any range of 2.0 kV or less and 1.0 kV or less.

[0095] In the pressure-sensitive adhesive forming composite sheet roll, the lower the static voltage, the more preferable, and the lower limit value of the static voltage is not particularly limited.

[0096] The static voltage can be, for example, 0.01 kV or more.

[0097] In the pressure-sensitive adhesive forming composite sheet roll, the static voltage can be appropriately adjusted within a range set by arbitrarily combining the above lower limit value and any upper limit value. For example, in one embodiment, the static voltage can be in any range of 0.01 - 3.0 kV, 0.01 - 2.0 kV, and 0.01 - 1.0 kV.

[0098] Based on the time point when the pressure-sensitive adhesive forming composite sheet is unwound from the pressure-sensitive adhesive forming composite sheet roll, the time until the static voltage is measured is preferably within 5 seconds. In the pressure-sensitive adhesive forming composite sheet that has just been unwound in this way, by quickly measuring the static voltage on the outermost surface on the release film side, it is possible to more accurately determine the difficulty of electrostatic charging of the pressure-sensitive adhesive forming composite sheet roll and the pressure-sensitive adhesive forming composite sheet.

[0099] Preferably, the pressure-sensitive adhesive forming composite sheet roll for measuring the static voltage is a pressure-sensitive adhesive forming composite sheet roll that has been stored for 7 days or more at a temperature of 23°C in an air atmosphere. By using the pressure-sensitive adhesive forming composite sheet roll stored under such conditions, it is possible to more accurately determine the difficulty of electrostatic charging of the pressure-sensitive adhesive forming composite sheet roll and the pressure-sensitive adhesive forming composite sheet.

[0100] Among them, an example of the storage conditions of the composite sheet roll for forming a protective film for measuring the static voltage shown here is provided. The storage conditions when using the composite sheet roll for forming a protective film of the present embodiment are not particularly limited and can be arbitrarily set according to the purpose.

[0101] The static voltage of the composite sheet roll for forming a protective film can be adjusted, for example, by adjusting the types and contents of the components contained in the outermost layer on the release film side, the types and contents of the components contained in the outermost layer on the support sheet side, and the like.

[0102] The size of the composite sheet for forming a protective film to be made into a roll can be arbitrarily selected according to the purpose and is not particularly limited.

[0103] For example, in terms of the high versatility of the composite sheet for forming a protective film, the length of the composite sheet for forming a protective film in the winding direction is preferably 10 to 100 m, and the length of the composite sheet for forming a protective film in the direction orthogonal to the winding direction is preferably 15 to 45 cm. For example, when the composite sheet for forming a protective film is a long rectangle, it is preferable that the long side direction of the composite sheet for forming a protective film is the winding direction. At this time, the length of the composite sheet for forming a protective film in the winding direction refers to the length in the long side direction of the sheet, and the length of the composite sheet for forming a protective film in the direction orthogonal to the winding direction refers to the width of the sheet.

[0104] When the composite sheet for forming a protective film has a plurality of the first laminated sheets or the second laminated sheets, the number of the first laminated sheets or the second laminated sheets laminated on one release film (in other words, the number of the first laminated sheets or the second laminated sheets per composite sheet roll for forming a protective film) is not particularly limited and can be, for example, 20 to 300 sheets.

[0105] When the composite sheet for forming a protective film has a plurality of the first laminated sheets or the second laminated sheets, the distance between adjacent first laminated sheets or between adjacent second laminated sheets is not particularly limited and can be, for example, 0.5 to 5 cm.

[0106] Here, the "distance between adjacent first laminated sheets or between adjacent second laminated sheets" refers to the shortest distance between the peripheral portions of adjacent first laminated sheets or between the peripheral portions of adjacent second laminated sheets.

[0107] The respective thicknesses of the respective layers constituting the composite sheet roll for forming a protective film and the composite sheet for forming a protective film will be described separately later, but the thickness of the composite sheet for forming a protective film (that is, the total thickness of all the layers constituting the composite sheet for forming a protective film) is preferably 100 to 200 μm.

[0108] The outer diameter of the composite sheet roll for forming a protective film is not particularly limited and can be, for example, 100 to 300 mm.

[0109] The inner diameter of the composite sheet roll for forming a protective film is not particularly limited and may be, for example, 30 to 200 mm.

[0110] Next, each layer constituting the composite sheet for forming a protective film and the composite sheet roll for forming a protective film will be described in more detail.

[0111] ◎ Support sheet

[0112] The support sheet can be used to fix a semiconductor wafer or semiconductor chip set having a protective film-forming film or a protective film on the back surface.

[0113] Examples of the support sheet include a support sheet having a base material and an adhesive layer provided on one surface of the base material; a support sheet composed only of the base material; a support sheet having a base material, an adhesive layer provided on one surface of the base material, and an intermediate layer provided on the surface of the adhesive layer opposite to the base material side; a support sheet having a base material and an intermediate layer provided on one surface of the base material, etc. When the support sheet has the adhesive layer or the intermediate layer, in the composite sheet for forming a protective film described below, the adhesive layer or the intermediate layer is disposed between the base material and the protective film-forming film.

[0114] The intermediate layer is a layer that functions as a layer other than the adhesive layer. Specific examples thereof include a peelability improvement layer. The peelability improvement layer is a layer for improving the peelability (ease of removal) of the protective film-forming film from the support sheet. However, the intermediate layer is not limited to the peelability improvement layer.

[0115] When using a support sheet having a base material and an adhesive layer, in the composite sheet for forming a protective film, the adhesive force or the adhesion between the support sheet and the protective film-forming film can be easily adjusted.

[0116] When using a support sheet composed only of the base material, the composite sheet for forming a protective film can be manufactured at low cost.

[0117] When using a support sheet having a base material, an adhesive layer, and an intermediate layer, new functions can be imparted to the support sheet or the composite sheet for forming a protective film. In addition, compared with the case of the above-mentioned adhesive layer, the adhesive force or the adhesion between the support sheet and the protective film-forming film can be adjusted more easily.

[0118] ○ Base material

[0119] The base material is in the form of a sheet or a film, and various resins can be cited as its constituent materials.

[0120] Examples of the resin include polyolefins such as low-density polyethylene (LDPE) and polypropylene (PP); ethylene-methacrylic acid copolymer (EMAA); polyvinyl chloride (PVC); polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate (PBT); polyethersulfone (PES); polyacrylate; polycarbonate (PC), etc.

[0121] The resin constituting the base material may be only one kind or two or more kinds.

[0122] The base material may be composed of one layer or two or more layers.

[0123] The thickness of the base material is preferably 40 to 300 μm, more preferably 50 to 200 μm, and still more preferably 60 to 100 μm. By making the thickness of the base material within such a range, the flexibility and the adhesiveness to the semiconductor wafer or semiconductor chip set of the composite sheet for forming the protective film are further improved.

[0124] Here, the "thickness of the base material" refers to the thickness of the entire base material. For example, the thickness of a base material composed of two or more layers refers to the total thickness of all the layers constituting the base material.

[0125] Preferably, the base material is a base material with high thickness accuracy, that is, a base material in which the deviation of the thickness is suppressed regardless of the position. Examples of the materials that can be used to form such a base material with high thickness accuracy among the above-mentioned constituent materials include polyolefins and polyethylene terephthalate.

[0126] In addition to the main constituent materials such as the resin, the base material may also contain various known additives such as fillers, colorants, antistatic agents, antioxidants, organic lubricants, catalysts, and softeners (plasticizers).

[0127] The base material can have adhesiveness on at least one surface by containing a specific range of components (for example, resin, etc.).

[0128] The base material can be transparent, opaque, can be colored according to the purpose, and can also be vapor-deposited with other layers.

[0129] In order to improve the adhesion to the layer provided thereon (for example, the adhesive layer, the intermediate layer, the film for forming the protective film, etc.), the surface of the base material can be subjected to roughening treatment based on sandblasting treatment, solvent treatment, etc.; oxidation treatment such as corona discharge treatment, electron beam irradiation treatment, plasma treatment, ozone-ultraviolet irradiation treatment, flame treatment, chromic acid treatment, hot air treatment, etc.

[0130] In addition, when storing the antistatic coating and the composite sheet roll for forming a protective film, the substrate may also have a layer for preventing the sheets from sticking to each other or preventing foreign substances from adhering to the sheets; a layer for preventing the substrate from sticking to the suction table, etc.

[0131] In addition, the substrate may also have a peeling treatment layer for improving the peelability of the layer provided thereon. The peeling treatment layer of the substrate is the same as the peeling treatment layer in the intermediate layer described later.

[0132] The substrate can be manufactured by a known method. For example, a substrate containing a resin can be manufactured by molding a resin composition containing the resin.

[0133] ○ Adhesive layer

[0134] The adhesive layer is in the form of a sheet or a film and contains an adhesive.

[0135] Examples of the adhesive include adhesive resins such as acrylic resins, urethane resins, rubber-based resins, silicone resins, epoxy resins, polyethylene ethers, polycarbonates, and ester resins, and acrylic resins are preferred.

[0136] In addition, in the present invention, "adhesive resin" includes a resin having adhesiveness and a resin having bonding properties. For example, the adhesive resin includes not only a resin having adhesiveness by itself, but also a resin that exhibits adhesiveness by being used in combination with other components such as additives, or a resin that exhibits bonding properties due to the presence of triggers such as heat or water.

[0137] The adhesive layer may be composed of one layer (single layer) or two or more layers.

[0138] The thickness of the adhesive layer is preferably 1 to 14 μm, more preferably 2 to 12 μm, and can be, for example, 3 to 8 μm. By making the thickness of the adhesive layer equal to or greater than the lower limit value, the effects brought about by providing the adhesive layer can be obtained more significantly. By making the thickness of the adhesive layer equal to or less than the upper limit value, the thickness can be prevented from becoming too thick.

[0139] Here, the "thickness of the adhesive layer" refers to the overall thickness of the adhesive layer.

[0140] The adhesive layer can be either energy ray curable or non-energy ray curable. The energy ray curable adhesive layer can easily adjust the physical properties before and after curing. For example, before picking up the semiconductor chip with a protective film or the semiconductor chip with a film for forming a protective film described later, by curing the energy ray curable adhesive layer, these semiconductor chips can be picked up more easily. Thus, in terms of being able to pick up the semiconductor chip more easily, it is preferred that the adhesive layer is energy ray curable.

[0141] "Adhesive Composition"

[0142] An adhesive layer can be formed using an adhesive composition containing an adhesive. For example, by applying the adhesive composition onto the surface where the adhesive layer is to be formed and drying it as needed, an adhesive layer can be formed at the target site. The content ratio of the components in the adhesive composition that do not vaporize at normal temperature is generally the same as the content ratio of the said components in the adhesive layer. In this specification, "normal temperature" refers to the temperature without special cooling or heating, that is, the ordinary temperature, for example, a temperature of 15 to 25 °C, etc.

[0143] The application of the adhesive composition can be carried out by known methods. As the application method of the adhesive composition, for example, methods using various coaters such as an air knife coater, a doctor blade coater, a rod coater, an intaglio coater, a roll coater, a roll knife coater, a curtain coater, a die coater, a blade coater, a screen coater, a Meyer rod coater, a kiss coater, etc. can be cited.

[0144] The drying conditions of the adhesive composition are not particularly limited.

[0145] When setting an adhesive layer on a substrate, for example, by applying the adhesive composition onto the substrate and drying it as needed, the adhesive layer can be laminated on the substrate. In addition, for example, by applying the adhesive composition onto a release film and drying it as needed, an adhesive layer is formed on the release film, and the exposed surface of this adhesive layer is adhered to one surface of the substrate, whereby the adhesive layer can be laminated on the substrate. The release film at this time can be removed at any time during the manufacturing process or the use process of the composite sheet for forming a protective film.

[0146] When the adhesive layer is energy ray curable, as the energy ray curable adhesive composition, for example, there can be cited: an adhesive composition (I-1) containing a non-energy ray curable adhesive resin (I-1a) (hereinafter, sometimes simply written as "adhesive resin (I-1a)") and an energy ray curable compound; an adhesive composition (I-2) containing an energy ray curable adhesive resin (I-2a) (hereinafter, sometimes simply written as "adhesive resin (I-2a)") in which an unsaturated group is introduced into the side chain of the said adhesive resin (I-1a); an adhesive composition (I-3) containing the said adhesive resin (I-2a) and an energy ray curable compound, etc.

[0147] When the adhesive layer is non-energy ray curable, as the non-energy ray curable adhesive composition, for example, there can be cited an adhesive composition (I-4) containing the said adhesive resin (I-1a), etc.

[0148] [Adhesive resin (I-1a)]

[0149] Preferably, the adhesive resin (I-1a) in the adhesive compositions (I-1), (I-2), (I-3) and (I-4) (hereinafter, these adhesive compositions are collectively abbreviated as "adhesive compositions (I-1) to (I-4)") is an acrylic resin.

[0150] Examples of the acrylic resin include acrylic polymers having at least structural units derived from (meth)acrylic acid alkyl esters.

[0151] Examples of the (meth)acrylic acid alkyl ester include (meth)acrylic acid alkyl esters in which the alkyl group constituting the alkyl ester has 1 to 20 carbon atoms, and preferably the alkyl group is linear or branched.

[0152] In addition, in this specification, "(meth)acrylic acid" is a concept including "acrylic acid" and "methacrylic acid". The same applies to terms similar to (meth)acrylic acid. For example, "(meth)acryloyl" is a concept including "acryloyl" and "methacryloyl", and "(meth)acrylate" is a concept including "acrylate" and "methacrylate".

[0153] Preferably, the acrylic polymer further has structural units derived from functional group-containing monomers in addition to the structural units derived from (meth)acrylic acid alkyl esters.

[0154] Examples of the functional group-containing monomer include functional group-containing monomers in which the functional group reacts with a crosslinking agent described later to generate a crosslinking starting point, or the functional group reacts with an unsaturated group in an unsaturated group-containing compound described later to introduce an unsaturated group into the side chain of the acrylic polymer.

[0155] Examples of the functional group-containing monomer include hydroxyl group-containing monomers, carboxyl group-containing monomers, amino group-containing monomers, epoxy group-containing monomers, etc.

[0156] In addition to the structural units derived from (meth)acrylic acid alkyl esters and the structural units derived from functional group-containing monomers, the acrylic polymer may further have structural units derived from other monomers.

[0157] The other monomers are not particularly limited as long as they can copolymerize with (meth)acrylic acid alkyl esters and the like.

[0158] Examples of the other monomers include styrene, α-methylstyrene, vinyltoluene, vinyl formate, vinyl acetate, acrylonitrile, acrylamide, etc.

[0159] In the adhesive compositions (I-1) to (I-4), the structural units of the acrylic polymer or the like acrylic resin may be only one kind, or may be two or more kinds.

[0160] In the acrylic polymer, relative to the total amount of the structural units, the content of the structural units derived from the functional group-containing monomer is preferably 1 to 35% by mass.

[0161] The pressure-sensitive adhesive resin (I-1a) contained in the pressure-sensitive adhesive composition (I-1) or the pressure-sensitive adhesive composition (I-4) may be only one kind, or may be two or more kinds.

[0162] In the pressure-sensitive adhesive composition (I-1) or the pressure-sensitive adhesive composition (I-4), the content of the pressure-sensitive adhesive resin (I-1a) is preferably 5 to 99% by mass relative to the total mass of the pressure-sensitive adhesive composition (I-1) or the pressure-sensitive adhesive composition (I-4).

[0163] [Pressure-sensitive adhesive resin (I-2a)]

[0164] The pressure-sensitive adhesive resin (I-2a) in the pressure-sensitive adhesive compositions (I-2) and (I-3) is obtained, for example, by reacting an unsaturated group-containing compound having an energy ray-polymerizable unsaturated group with a functional group in the pressure-sensitive adhesive resin (I-1a).

[0165] The unsaturated group-containing compound is a compound that further has a group capable of bonding to the pressure-sensitive adhesive resin (I-1a) by reacting with a functional group in the pressure-sensitive adhesive resin (I-1a) in addition to having the energy ray-polymerizable unsaturated group.

[0166] Examples of the energy ray-polymerizable unsaturated group include (meth)acryloyl, vinyl (ethylene), allyl (2-propenyl), etc., and (meth)acryloyl is preferred.

[0167] Examples of the group capable of bonding to the functional group in the pressure-sensitive adhesive resin (I-1a) include an isocyanate group and a glycidyl group capable of bonding to a hydroxyl group or an amino group, and a hydroxyl group and an amino group capable of bonding to a carboxyl group or an epoxy group.

[0168] Examples of the unsaturated group-containing compound include (meth)acryloyloxyethyl isocyanate, (meth)acryloyl isocyanate, (meth)acrylic acid glycidyl ester, etc.

[0169] The pressure-sensitive adhesive resin (I-2a) contained in the pressure-sensitive adhesive composition (I-2) or (I-3) may be only one kind, or may be two or more kinds.

[0170] In the pressure-sensitive adhesive composition (I-2) or (I-3), preferably, the content of the pressure-sensitive adhesive resin (I-2a) accounts for 5 to 99% by mass relative to the total mass of the pressure-sensitive adhesive composition (I-2) or (I-3).

[0171] [Energy ray curable compound]

[0172] As the energy ray curable compound in the pressure-sensitive adhesive compositions (I-1) and (I-3), monomers or oligomers having an energy ray polymerizable unsaturated group and capable of being cured by irradiation with energy rays can be cited.

[0173] As monomers in the energy ray curable compound, for example, polyfunctional (meth)acrylates such as trimethylolpropane tri(meth)acrylate, pentaerythritol (meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol (meth)acrylate, etc.; urethane (meth)acrylate; polyester (meth)acrylate; polyether (meth)acrylate; epoxy (meth)acrylate, etc. can be cited.

[0174] As oligomers in the energy ray curable compound, for example, oligomers formed by polymerizing the monomers exemplified above can be cited.

[0175] The energy ray curable compound contained in the pressure-sensitive adhesive composition (I-1) or (I-3) may be only one kind or two or more kinds.

[0176] In the pressure-sensitive adhesive composition (I-1), preferably, the content of the energy ray curable compound accounts for 1 to 95% by mass relative to the total mass of the pressure-sensitive adhesive composition (I-1).

[0177] In the pressure-sensitive adhesive composition (I-3), preferably, the content of the energy ray curable compound is 0.01 to 300 parts by mass relative to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a).

[0178] [Crosslinking agent]

[0179] When the acrylic polymer having a structural unit derived from a functional group-containing monomer in addition to a structural unit derived from an alkyl (meth)acrylate is used as the pressure-sensitive adhesive resin (I-1a), preferably, the pressure-sensitive adhesive composition (I-1) or (I-4) further contains a crosslinking agent.

[0180] In addition, for example, when the same acrylic polymer having a structural unit derived from a functional group-containing monomer as in the pressure-sensitive adhesive resin (I-1a) is used as the pressure-sensitive adhesive resin (I-2a), the pressure-sensitive adhesive composition (I-2) or (I-3) may further contain a crosslinking agent.

[0181] The crosslinking agent crosslinks the pressure-sensitive adhesive resins (I-1a) with each other or crosslinks the pressure-sensitive adhesive resins (I-2a) with each other, for example, by reacting with the functional groups.

[0182] Examples of the crosslinking agent include isocyanate-based crosslinking agents (crosslinking agents having an isocyanate group) such as toluene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, and adducts of these diisocyanates; epoxy-based crosslinking agents (crosslinking agents having a glycidyl group) such as ethylene glycol diglycidyl ether; aziridine-based crosslinking agents (crosslinking agents having an aziridine group) such as hexa[1-(2-methyl)-aziridinyl]triphosphatriazine; metal chelate-based crosslinking agents (crosslinking agents having a metal chelate structure) such as aluminum chelate; and isocyanurate-based crosslinking agents (crosslinking agents having an isocyanurate skeleton).

[0183] The crosslinking agent contained in the pressure-sensitive adhesive composition (I-1), (I-2), or (I-4) may be only one kind or two or more kinds.

[0184] In the pressure-sensitive adhesive composition (I-1) or (I-4), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass, for example, any range of 0.01 to 35 parts by mass and 0.01 to 25 parts by mass, relative to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-1a).

[0185] In the pressure-sensitive adhesive composition (I-2) or (I-3), the content of the crosslinking agent is preferably 0.01 to 50 parts by mass, for example, any range of 0.01 to 35 parts by mass, 0.01 to 20 parts by mass, and 0.01 to 10 parts by mass, relative to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a).

[0186] [Photoinitiator]

[0187] The pressure-sensitive adhesive compositions (I-1), (I-2), and (I-3) (hereinafter, these pressure-sensitive adhesive compositions are collectively abbreviated as "pressure-sensitive adhesive compositions (I-1) to (I-3)") may further contain a photoinitiator. Even when the pressure-sensitive adhesive compositions (I-1) to (I-3) containing a photoinitiator are irradiated with low-energy energy rays such as ultraviolet rays, they sufficiently undergo a curing reaction.

[0188] Examples of the photopolymerization initiator include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin benzoate, benzoin benzoate methyl ester, and benzoin dimethyl ketal; acetophenone compounds such as acetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, and 2-hydroxy-1-(4-(4-(2-hydroxy-2-methylpropanoyl)benzyl)phenyl)-2-methylpropan-1-one; acylphosphine oxide compounds such as phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide and 2,4,6-trimethylbenzoyldiphenylphosphine oxide; sulfides such as benzyl phenyl sulfide and tetramethylthiuram monosulfide; α-ketol compounds such as 1-hydroxycyclohexyl phenyl ketone; azo compounds such as azobisisobutyronitrile; titanocene compounds such as titanocene; thioxanthone compounds such as thioxanthone; peroxide compounds; diketone compounds such as butanedione; benzil; dibenzil; benzophenone; 2,4-diethylthioxanthone; 1,2-diphenylmethane; 2-hydroxy-2-methyl-1-[4-(1-methylethenyl)phenyl]acetone; quinone compounds such as 1-chloroanthraquinone and 2-chloroanthraquinone.

[0189] In addition, as the photopolymerization initiator, photosensitizers such as amines can also be used, for example.

[0190] The photopolymerization initiator contained in the pressure-sensitive adhesive compositions (I-1) to (I-3) may be only one kind or two or more kinds.

[0191] In the pressure-sensitive adhesive composition (I-1), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the content of the energy ray curable compound.

[0192] In the pressure-sensitive adhesive composition (I-2), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the content of the pressure-sensitive adhesive resin (I-2a), and can be, for example, any range of 0.01 to 10 parts by mass and 0.01 to 5 parts by mass.

[0193] In the pressure-sensitive adhesive composition (I-3), the content of the photopolymerization initiator is preferably 0.01 to 20 parts by mass relative to 100 parts by mass of the total content of the pressure-sensitive adhesive resin (I-2a) and the energy ray curable compound.

[0194] [Other additives]

[0195] Within the range not impairing the effects of the present invention, the pressure-sensitive adhesive compositions (I-1) to (I-4) may further contain other additives that do not belong to any of the above components.

[0196] Examples of the other additives include known additives such as antistatic agents, antioxidants, softeners (plasticizers), filling materials (fillers), rust inhibitors, colorants (pigments, dyes), sensitizers, tackifiers, reaction retardants, crosslinking accelerators (catalysts), and the like.

[0197] In addition, the reaction retardant refers to, for example, an additive that inhibits an unintended crosslinking reaction caused by the action of a catalyst mixed in the pressure-sensitive adhesive compositions (I-1) to (I-4) during storage. Examples of the reaction retardant include reaction retardants that form a chelate coordination compound (chelate complex) using a chelate against the catalyst. More specifically, reaction retardants having two or more carbonyl groups (-C(=O)-) in one molecule can be cited.

[0198] The other additives contained in the pressure-sensitive adhesive compositions (I-1) to (I-4) may be only one kind or two or more kinds.

[0199] The content of the other additives in the pressure-sensitive adhesive compositions (I-1) to (I-4) is not particularly limited and can be appropriately selected according to their types.

[0200] [Solvent]

[0201] The pressure-sensitive adhesive compositions (I-1) to (I-4) may contain a solvent. By containing a solvent, the coating adaptability of the pressure-sensitive adhesive compositions (I-1) to (I-4) to the coating target surface is improved.

[0202] In addition, in this specification, unless otherwise specified, "solvent" includes not only a solvent that dissolves the target component but also a concept of a dispersion medium that disperses the target component.

[0203] Preferably, the solvent is an organic solvent. Examples of the organic solvent include ketones such as methyl ethyl ketone and acetone; esters (carboxylic acid esters) such as ethyl acetate; ethers such as tetrahydrofuran and dioxane; aliphatic hydrocarbons such as cyclohexane and n-hexane; aromatic hydrocarbons such as toluene and xylene; alcohols such as 1-propanol and 2-propanol.

[0204] The solvent contained in the pressure-sensitive adhesive compositions (I-1) to (I-4) may be only one kind or two or more kinds.

[0205] The content of the solvent in the pressure-sensitive adhesive compositions (I-1) to (I-4) is not particularly limited and can be appropriately adjusted.

[0206] 《Preparation Method of Pressure-Sensitive Adhesive Composition》

[0207] The pressure-sensitive adhesive compositions such as the pressure-sensitive adhesive compositions (I-1) to (I-4) can be obtained by blending the respective components for constituting the pressure-sensitive adhesive composition, that is, by blending the said pressure-sensitive adhesive and components other than the said pressure-sensitive adhesive as required and the like.

[0208] There is no particular limitation on the order of addition when blending the respective components, and two or more components can be added simultaneously.

[0209] There is no particular limitation on the method of mixing the respective components during blending, and it can be appropriately selected from the following known methods: a method of mixing by rotating a stirrer or stirring blade or the like; a method of mixing using a mixer; a method of mixing by applying ultrasonic waves or the like.

[0210] As long as each blended component does not deteriorate, there is no particular limitation on the temperature and time when adding and mixing the respective components, and they can be appropriately adjusted, but a temperature of 15 to 30°C is preferred.

[0211] ○ Intermediate layer

[0212] The said intermediate layer is in sheet form or film form.

[0213] In the composite sheet for forming a protective film, the intermediate layer is disposed between the pressure-sensitive adhesive layer and the film for forming a protective film.

[0214] The type of the intermediate layer can be arbitrarily selected according to the purpose and there is no particular limitation.

[0215] The intermediate layer can be transparent, opaque, or can be colored according to the purpose.

[0216] The intermediate layer can be formed by a known method according to its type. For example, an intermediate layer mainly composed of a resin can be formed by molding a resin composition containing the said resin.

[0217] As the intermediate layer, for example, a layer with improved peelability having a peel treatment on one of its surfaces can be cited.

[0218] · Layer with improved peelability

[0219] As the layer with improved peelability, for example, a layer composed of multiple layers having a resin layer and a peel treatment layer provided on the said resin layer can be cited.

[0220] In the composite sheet for forming a protective film, the layer with improved peelability is disposed such that its peel treatment layer faces the side of the film for forming a protective film.

[0221] The said peel treatment layer can be formed, for example, by treating the resin layer with various known peel agents such as alkyds, silicones, fluorides, unsaturated polyesters, polyolefins, or waxes, and is preferably formed using a silicone peel agent.

[0222] The resin used as the constituent material of the resin layer can be appropriately selected according to the purpose, and there is no particular limitation.

[0223] As a preferred resin, for example, the same resin as the resin used as the constituent material of the substrate can be cited.

[0224] The resin layer may be composed of a single layer or two or more layers.

[0225] The thickness of the peelability improvement layer (the total thickness of the resin layer and the peeling treatment layer) is preferably 10 to 2000 nm, more preferably 25 to 1500 nm, and particularly preferably 50 to 1200 nm. By making the thickness of the peelability improvement layer equal to or greater than the lower limit value, the function of the peelability improvement layer becomes more significant, and the effect of suppressing breakage such as cutting of the peelability improvement layer becomes higher. By making the thickness of the peelability improvement layer equal to or less than the upper limit value, it becomes easier to pick up a semiconductor chip having a protective film or a film for forming a protective film described later on the back surface.

[0226] ◎ Film for forming protective film

[0227] The film for forming a protective film forms a protective film for protecting the back surface of a semiconductor wafer and a semiconductor chip.

[0228] The film for forming a protective film is soft and can be easily attached to an object to be attached such as a semiconductor wafer or a semiconductor chip.

[0229] The film for forming a protective film can function as a protective film through its curing, or can function as a protective film in an uncured state. The film for forming a protective film that functions as a protective film in an uncured state is regarded as forming a protective film at the stage of attaching it to the back surface of a semiconductor wafer or a semiconductor chip group.

[0230] When a protective film is formed by thermally curing the film for forming a protective film, unlike the case of curing it by irradiation with energy rays, even if the thickness of the film for forming a protective film is thick, it will be sufficiently cured by heating the film for forming a protective film, so a protective film with high protective performance can be formed. In addition, by using a usual heating means such as a heating oven, a plurality of films for forming a protective film can be heated together and thermally cured.

[0231] When the film for forming a protective film is cured by irradiation with energy rays to form a protective film, unlike the case of thermally curing it, the protective film forming composite sheet does not need to have heat resistance, and a wide range of protective film forming composite sheets can be constituted. In addition, by irradiation with energy rays, it can be cured in a short time.

[0232] When it is used as a protective film without curing the film for forming the protective film, since the curing process can be omitted, a semiconductor chip with a protective film can be manufactured with a simplified process.

[0233] In terms of being able to form a protective film with higher protective performance, it is preferable that the film for forming the protective film is thermosetting or energy ray curable.

[0234] Regardless of whether the film for forming the protective film is curable or non-curable, and when the film for forming the protective film is curable, regardless of whether it is thermosetting or energy ray curable, the film for forming the protective film can be composed of one layer or two or more layers.

[0235] Regardless of whether the film for forming the protective film is curable or non-curable, and when the film for forming the protective film is curable, regardless of whether it is thermosetting or energy ray curable, the thickness of the film for forming the protective film is preferably 1 to 100 μm, more preferably 3 to 80 μm, further preferably 5 to 60 μm, and particularly preferably 7 to 25 μm. By making the thickness of the film for forming the protective film be above the lower limit value, a protective film with higher protective performance can be formed. By making the thickness of the film for forming the protective film be below the upper limit value, it is possible to avoid the thickness becoming too thick.

[0236] Here, the "thickness of the film for forming the protective film" refers to the overall thickness of the film for forming the protective film.

[0237] "Composition for Forming Protective Film"

[0238] The film for forming the protective film can be formed by using a composition for forming the protective film containing its constituent materials. For example, by coating the composition for forming the protective film on the surface to be formed with the protective film and drying it as needed, the film for forming the protective film can be formed. The content ratio of the components that do not vaporize at normal temperature in the composition for forming the protective film is usually the same as the content ratio of the components of the film for forming the protective film.

[0239] The thermosetting film for forming the protective film can be formed by using a thermosetting composition for forming the protective film, the energy ray curable film for forming the protective film can be formed by using an energy ray curable composition for forming the protective film, and the non-curable film for forming the protective film can be formed by using a non-curable composition for forming the protective film. In addition, in this specification, when the film for forming the protective film has both thermosetting and energy ray curable properties, and the contribution of the thermal curing of the film for forming the protective film to the formation of the protective film is greater than the contribution of the energy ray curing, the film for forming the protective film is regarded as thermosetting. On the contrary, when the contribution of the energy ray curing of the film for forming the protective film to the formation of the protective film is greater than the contribution of the thermal curing, the film for forming the protective film is regarded as energy ray curable.

[0240] For example, the composition for forming a protective film can be coated by the same method as that used for coating the above-mentioned adhesive composition.

[0241] The drying conditions of the composition for forming a protective film are not particularly limited. Among them, when the composition for forming a protective film contains a solvent described later, heating and drying are preferably performed. And, the composition for forming a protective film containing a solvent is preferably heated and dried under the conditions of 70 to 130°C for 10 seconds to 5 minutes. Among them, it is preferable to perform heating and drying in such a manner that the thermosetting protective film-forming composition itself and the thermosetting protective film-forming film formed from this composition are not thermally cured.

[0242] Hereinafter, the thermosetting protective film-forming film, the energy ray-curable protective film-forming film, and the non-curable protective film-forming film will be described in turn.

[0243] ○ Thermosetting protective film-forming film

[0244] As long as the protective film has a degree of curing sufficient to exhibit its function, the curing conditions for thermally curing the thermosetting protective film-forming film to form a protective film are not particularly limited.

[0245] For example, the heating temperature during the thermal curing of the thermosetting protective film-forming film is preferably 100 to 200°C, more preferably 110 to 180°C, and particularly preferably 120 to 170°C. And, the heating time during the thermal curing is preferably 0.5 to 5 hours, more preferably 0.5 to 3 hours, and particularly preferably 1 to 2 hours.

[0246] As a preferable thermosetting protective film-forming film, for example, a thermosetting protective film-forming film containing a polymer component (A) and a thermosetting component (B) can be cited. The polymer component (A) is a component that can be regarded as being formed by a polymerization reaction of a polymerizable compound. In addition, the thermosetting component (B) is a component that can undergo a curing (polymerization) reaction with heat as the reaction inducer. In addition, in this specification, the polymerization reaction also includes a polycondensation reaction.

[0247] <Thermosetting protective film-forming composition (III-1)>

[0248] As a preferable thermosetting protective film-forming composition, for example, a thermosetting protective film-forming composition (III-1) containing the polymer component (A) and the thermosetting component (B) (in this specification, sometimes simply written as "composition (III-1)") etc. can be cited.

[0249] [Polymer component (A)]

[0250] The polymer component (A) is a polymer compound used to impart film-forming properties and flexibility, etc. to a film for forming a thermosetting protective film. The polymer component (A) has thermoplasticity and does not have thermosetting properties. In addition, in this specification, the polymer compound also includes the product of a polycondensation reaction.

[0251] The polymer component (A) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, or two or more kinds.

[0252] Examples of the polymer component (A) include an acrylic resin, a urethane resin, a phenoxy resin, a silicone resin, a saturated polyester resin, etc., and an acrylic resin is preferred.

[0253] As the acrylic resin in the polymer component (A), known acrylic polymers can be cited.

[0254] The weight-average molecular weight (M W ) of the acrylic resin is preferably 10,000 to 2,000,000, more preferably 100,000 to 1,500,000. By making the weight-average molecular weight of the acrylic resin be above the lower limit value, the shape stability (stability over time during storage) of the film for forming a thermosetting protective film is improved. In addition, by making the weight-average molecular weight of the acrylic resin be below the upper limit value, the film for forming a thermosetting protective film easily follows the uneven surface of the adherend, and the generation of voids, etc. between the adherend and the film for forming a thermosetting protective film is further suppressed.

[0255] In addition, in this specification, unless otherwise specified, the "weight-average molecular weight" refers to the polystyrene conversion value measured by gel permeation chromatography (GPC) method.

[0256] The glass transition temperature (Tg) of the acrylic resin is preferably -60 to 70 °C, more preferably -30 to 50 °C. By making the Tg of the acrylic resin be above the lower limit value, for example, the adhesion between the cured product of the film for forming a protective film and the support sheet can be suppressed, and the peelability of the support sheet can be appropriately improved. In addition, by making the Tg of the acrylic resin be below the upper limit value, the adhesion between the thermosetting protective film-forming film and its cured product and the adherend is improved.

[0257] When the acrylic resin has two or more structural units, the glass transition temperature (Tg) of the acrylic resin can be calculated using the Fox equation. As the Tg of the monomer from which the structural unit is derived used at this time, the values described in a polymer data handbook or an adhesion handbook can be used.

[0258] As the acrylic resin, for example, a polymer of one or more (meth)acrylates can be cited; a copolymer of two or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide, etc.

[0259] As the (meth)acrylate constituting the acrylic resin, for example, (meth)acrylic acid alkyl ester, (meth)acrylic acid cycloalkyl ester, (meth)acrylic acid aralkyl ester, (meth)acrylic acid cycloalkenyl ester, (meth)acrylic acid cycloalkenyloxyalkyl ester, (meth)acrylamide, (meth)acrylate containing glycidyl group, (meth)acrylate containing hydroxyl group, (meth)acrylate containing substituted amino group, etc. can be cited. Here, "substituted amino" means a group in which one or two hydrogen atoms of an amino group are replaced by a group other than a hydrogen atom.

[0260] In addition to the (meth)acrylate, the acrylic resin can also be copolymerized from one or more monomers selected from (meth)acrylic acid, itaconic acid, vinyl acetate, acrylonitrile, styrene, N-methylolacrylamide, etc.

[0261] The monomers constituting the acrylic resin can be only one kind or two or more kinds.

[0262] The acrylic resin can have functional groups such as vinyl group, (meth)acryloyl group, amino group, hydroxyl group, carboxyl group, isocyanate group, etc. that can bond with other compounds. The functional groups of the acrylic resin can bond with other compounds via the crosslinking agent (F) described later, or can directly bond with other compounds without passing through the crosslinking agent (F). By bonding the acrylic resin with other compounds through the functional groups, the reliability of the package obtained by using the composite sheet for forming a protective film tends to be improved.

[0263] In the present invention, as the polymer component (A), a thermoplastic resin other than the acrylic resin (hereinafter sometimes simply written as "thermoplastic resin") can be used alone without using the acrylic resin, or the acrylic resin and a thermoplastic resin other than the acrylic resin can be used simultaneously. By using the thermoplastic resin, the peelability of the protective film from the support sheet may be improved, or the film for forming a thermosetting protective film is likely to follow the uneven surface of the adherend, and the generation of voids between the adherend and the film for forming a thermosetting protective film can be further suppressed.

[0264] The weight average molecular weight of the thermoplastic resin is preferably 1000 to 100000, more preferably 3000 to 80000.

[0265] The glass transition temperature (Tg) of the thermoplastic resin is preferably -30 to 150 °C, more preferably -20 to 120 °C.

[0266] Examples of the thermoplastic resin include polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, polystyrene, and the like.

[0267] The thermoplastic resin contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds.

[0268] In the composition (III-1), regardless of the type of the polymer component (A), the proportion of the content of the polymer component (A) relative to the total content of all components other than the solvent (that is, the proportion of the content of the polymer component (A) in the film for forming a thermosetting protective film relative to the total mass of the film for forming a thermosetting protective film) is preferably 10 to 85% by mass, more preferably 15 to 70% by mass, and further preferably 20 to 60% by mass. For example, it may be any range of 20 to 45% by mass and 20 to 35% by mass, or may be any range of 35 to 60% by mass and 45 to 60% by mass.

[0269] The polymer component (A) sometimes belongs to the thermosetting component (B). In the present invention, when the composition (III-1) contains a component that belongs to both the polymer component (A) and the thermosetting component (B), the composition (III-1) is regarded as containing the polymer component (A) and the thermosetting component (B).

[0270] [Thermosetting component (B)]

[0271] The thermosetting component (B) has thermosetting properties and is a component for thermally curing the film for forming a thermosetting protective film.

[0272] The thermosetting component (B) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds.

[0273] Examples of the thermosetting component (B) include epoxy-based thermosetting resins, polyimide resins, unsaturated polyester resins, etc., and epoxy-based thermosetting resins are preferred.

[0274] (Epoxy-based thermosetting resin)

[0275] The epoxy-based thermosetting resin is composed of an epoxy resin (B1) and a thermosetting agent (B2).

[0276] The epoxy-based thermosetting resin contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds.

[0277] ·Epoxy resin (B1)

[0278] As the epoxy resin (B1), known epoxy resins can be cited. For example, polyfunctional epoxy resins, biphenyl compounds, bisphenol A diglycidyl ether and its hydrides, cresol novolac epoxy resins, dicyclopentadiene-type epoxy resins, biphenyl-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, epoxy compounds having two or more functional groups such as phenylene-skeleton-type epoxy resins can be cited.

[0279] As the epoxy resin (B1), an epoxy resin having an unsaturated hydrocarbon group can also be used. The compatibility of an epoxy resin having an unsaturated hydrocarbon group with an acrylic resin is greater than that of an epoxy resin not having an unsaturated hydrocarbon group with an acrylic resin. Therefore, by using an epoxy resin having an unsaturated hydrocarbon group, the reliability of a semiconductor chip with a protective film obtained by using a composite sheet for forming a protective film is improved.

[0280] As the epoxy resin having an unsaturated hydrocarbon group, for example, a compound in which a part of the epoxy groups of a polyfunctional epoxy resin is converted into a group having an unsaturated hydrocarbon group can be cited. Such a compound can be obtained, for example, by subjecting (meth)acrylic acid or its derivative to an addition reaction with an epoxy group.

[0281] In addition, as the epoxy resin having an unsaturated hydrocarbon group, for example, a compound in which a group having an unsaturated hydrocarbon group is directly bonded to an aromatic ring or the like constituting the epoxy resin can be cited.

[0282] The unsaturated hydrocarbon group is a polymerizable unsaturated group. Specific examples thereof include ethylene group (vinyl group), 2-propenyl group (allyl group), (meth)acryloyl group, (meth)acrylamide group, etc., and an acryloyl group is preferred.

[0283] The number average molecular weight of the epoxy resin (B1) is not particularly limited, but from the viewpoints of the curability of the film for forming a thermosetting protective film and the strength and heat resistance of the protective film, it is preferably 300 to 30,000, more preferably 300 to 10,000, and particularly preferably 300 to 3,000.

[0284] The epoxy equivalent of the epoxy resin (B1) is preferably 100 to 1000 g / eq, more preferably 150 to 950 g / eq.

[0285] The epoxy resin (B1) can be used alone or two or more thereof can be used simultaneously.

[0286] · Heat curing agent (B2)

[0287] The heat curing agent (B2) functions as a curing agent for the epoxy resin (B1).

[0288] As the thermal curing agent (B2), for example, compounds having two or more functional groups capable of reacting with an epoxy group in one molecule can be cited. Examples of the functional group include a phenolic hydroxyl group, an alcoholic hydroxyl group, an amino group, a carboxyl group, a group formed by acid anhydride formation, etc., with a phenolic hydroxyl group, an amino group, or a group formed by acid anhydride formation being preferred, and a phenolic hydroxyl group or an amino group being more preferred.

[0289] As the phenolic curing agent having a phenolic hydroxyl group in the thermal curing agent (B2), for example, polyfunctional phenolic resins, biphenol, novolak-type phenolic resins, dicyclopentadiene-type phenolic resins, aralkyl-type phenolic resins, etc. can be cited.

[0290] As the amine curing agent having an amino group in the thermal curing agent (B2), for example, dicyandiamide, etc. can be cited.

[0291] The thermal curing agent (B2) may have an unsaturated hydrocarbon group.

[0292] As the thermal curing agent (B2) having an unsaturated hydrocarbon group, for example, compounds in which a part of the hydroxyl groups of a phenolic resin are substituted with a group having an unsaturated hydrocarbon group, compounds in which a group having an unsaturated hydrocarbon group is directly bonded to the aromatic ring of a phenolic resin, etc. can be cited.

[0293] The unsaturated hydrocarbon group in the thermal curing agent (B2) is the same as the unsaturated hydrocarbon group in the above-mentioned epoxy resin having an unsaturated hydrocarbon group.

[0294] When using a phenolic curing agent as the thermal curing agent (B2), from the viewpoint of improving the peelability of the protective film from the support sheet, it is preferred that the softening point or glass transition temperature of the thermal curing agent (B2) is high.

[0295] In the thermal curing agent (B2), for example, it is preferred that the number average molecular weight of resin components such as polyfunctional phenolic resins, novolak-type phenolic resins, dicyclopentadiene-type phenolic resins, aralkyl-type phenolic resins, etc. is 300 to 30000, more preferably 400 to 10000, and particularly preferably 500 to 3000.

[0296] In the thermal curing agent (B2), for example, the molecular weights of non-resin components such as biphenol and dicyandiamide are not particularly limited, and are preferably 60 to 500, for example.

[0297] The thermal curing agent (B2) can be used alone or two or more kinds can be used simultaneously.

[0298] In the composition (III-1) and the film for forming a thermosetting protective film, with respect to the content of 100 parts by mass of the epoxy resin (B1), the content of the thermosetting agent (B2) is preferably 0.1 to 100 parts by mass, more preferably 0.5 to 50 parts by mass, and for example, can be any range among 0.5 to 25 parts by mass, 0.5 to 10 parts by mass, and 0.5 to 5 parts by mass. By making the content of the thermosetting agent (B2) above the lower limit value, it is easier to cure the film for forming a thermosetting protective film. By making the content of the thermosetting agent (B2) below the upper limit value, the moisture absorption rate of the film for forming a thermosetting protective film is reduced, and the reliability of the package obtained using the composite sheet for forming a protective film is further improved.

[0299] In the composition (III-1) and the film for forming a thermosetting protective film, with respect to the content of 100 parts by mass of the polymer component (A), the content of the thermosetting component (B) (for example, the total content of the epoxy resin (B1) and the thermosetting agent (B2)) is preferably 5 to 120 parts by mass, more preferably 5 to 80 parts by mass, and for example, can be any range among 5 to 40 parts by mass, 5 to 20 parts by mass, and 5 to 10 parts by mass, and can also be any range among 40 to 80 parts by mass, 50 to 75 parts by mass, and 60 to 75 parts by mass. By making the content of the thermosetting component (B) in such a range, for example, the adhesion between the cured product of the film for forming a protective film and the support sheet can be suppressed, and the peelability of the support sheet is improved.

[0300] [Curing accelerator (C)]

[0301] The composition (III-1) and the film for forming a thermosetting protective film may also contain a curing accelerator (C). The curing accelerator (C) is a component for adjusting the curing rate of the composition (III-1).

[0302] As preferred curing accelerators (C), for example, tertiary amines such as triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, tris(dimethylaminomethyl)phenol, etc.; imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, etc. (imidazoles in which one or more hydrogen atoms are replaced by groups other than hydrogen atoms); organic phosphines such as tributylphosphine, diphenylphosphine, triphenylphosphine, etc. (phosphines in which one or more hydrogen atoms are replaced by organic groups); tetraphenylborate salts such as tetraphenylphosphonium tetraphenylborate, triphenylphosphine tetraphenylborate, etc.

[0303] The curing accelerator (C) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, or two or more kinds.

[0304] When using the curing accelerator (C), in the composition (III-1) and the film for forming a thermosetting protective film, the content of the curing accelerator (C) is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 7 parts by mass, relative to the content of 100 parts by mass of the thermosetting component (B). By making the content of the curing accelerator (C) be above the lower limit value, the effects brought about by using the curing accelerator (C) can be obtained more significantly. In addition, by making the content of the curing accelerator (C) be below the upper limit value, for example, the effect of suppressing the movement and segregation of the highly polar curing accelerator (C) to the adhesive interface side with the adherend in the film for forming a thermosetting protective film under high temperature and high humidity conditions is improved. As a result, the reliability of the semiconductor chip with a protective film obtained by using the composite sheet for forming a protective film is further improved.

[0305] [Filler (D)]

[0306] The composition (III-1) and the film for forming a thermosetting protective film may also contain a filler (D). By making the film for forming a thermosetting protective film contain the filler (D), it is easy to adjust the thermal expansion coefficient of the film for forming a thermosetting protective film and the protective film. By optimizing the thermal expansion coefficient with respect to the object to be formed with the protective film, the reliability of the semiconductor chip with a protective film obtained by using the composite sheet for forming a protective film is further improved. In addition, by making the film for forming a thermosetting protective film contain the filler (D), it is also possible to reduce the moisture absorption rate of the protective film or improve the heat dissipation property.

[0307] The filler (D) can be either an organic filler or an inorganic filler, but an inorganic filler is preferred.

[0308] As preferred inorganic fillers, for example, powders such as silica, alumina, talc, calcium carbonate, titanium white, iron oxide red, silicon carbide, boron nitride, etc. can be cited; beads formed by spheroidizing these inorganic fillers; surface-modified products of these inorganic fillers; single crystal fibers of these inorganic fillers; glass fibers, etc.

[0309] Among them, the inorganic filler is preferably silica or alumina, and more preferably silica.

[0310] The filler (D) contained in the composition (III-1) and the film for forming a thermosetting protective film can be only one kind, or two or more kinds.

[0311] In the composition (III-1), the content ratio of the filler (D) relative to the total content of all components except the solvent (i.e., the ratio of the content of the filler (D) in the film for forming a thermosetting protective film relative to the total mass of the film for forming a thermosetting protective film) is preferably 15 to 70% by mass, more preferably 30 to 60% by mass. For example, it can be any range among 35 to 60% by mass, 40 to 60% by mass, and 45 to 60% by mass, and can also be any range among 30 to 55% by mass, 30 to 50% by mass, and 30 to 45% by mass. By setting the ratio within such a range, it is easier to adjust the thermal expansion coefficients of the above-mentioned film for forming a thermosetting protective film and the protective film.

[0312] [Coupling agent (E)]

[0313] The composition (III-1) and the film for forming a thermosetting protective film may also contain a coupling agent (E). By using a substance having a functional group capable of reacting with an inorganic compound or an organic compound as the coupling agent (E), the adhesiveness and the sealing property of the film for forming a thermosetting protective film to the adherend can be improved. In addition, by using the coupling agent (E), the water resistance of the protective film formed from the film for forming a thermosetting protective film is improved without impairing the heat resistance.

[0314] Preferably, the coupling agent (E) is a compound having a functional group capable of reacting with the functional groups possessed by the polymer component (A), the thermosetting component (B), etc., and more preferably a silane coupling agent.

[0315] As the preferred silane coupling agent, for example, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxymethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-(2-aminoethylamino)propyltrimethoxysilane, 3-(2-aminoethylamino)propylmethyldiethoxysilane, 3-(phenylamino)propyltrimethoxysilane, 3-anilinopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, bis(3-triethoxysilylpropyl)tetrasulfide, methyltrimethoxysilane, methyltriethoxysilane, vinyltrimethoxysilane, vinyltriacetoxysilane, imidazole silane, etc. can be cited.

[0316] The coupling agent (E) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, or two or more kinds.

[0317] When using the coupling agent (E), in the composition (III-1) and the film for forming a thermosetting protective film, relative to the total content of 100 parts by mass of the polymer component (A) and the thermosetting component (B), the content of the coupling agent (E) is preferably 0.03 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and particularly preferably 0.1 to 2 parts by mass. By making the content of the coupling agent (E) above the lower limit value, the effects brought by using the coupling agent (E) such as more significantly obtaining an improvement in the dispersibility of the filler (D) in the resin and an improvement in the adhesiveness between the film for forming a thermosetting protective film and the adherend can be obtained. In addition, by making the content of the coupling agent (E) below the upper limit value, the generation of outgas can be further suppressed.

[0318] [Crosslinking agent (F)]

[0319] When using a substance having functional groups such as vinyl, (meth)acryloyl, amino, hydroxyl, carboxyl, isocyanate group, etc. that can bond with other compounds, such as the above-mentioned acrylic resin, as the polymer component (A), the composition (III-1) and the film for forming a thermosetting protective film may also contain a crosslinking agent (F). The crosslinking agent (F) is a component for bonding and crosslinking the functional groups in the polymer component (A) with other compounds. By crosslinking in this way, the initial adhesiveness and cohesion of the film for forming a thermosetting protective film can be adjusted.

[0320] Examples of the crosslinking agent (F) include organic polyisocyanate compounds, organic polyimine compounds, metal chelate crosslinking agents (crosslinking agents having a metal chelate structure), aziridine crosslinking agents (crosslinking agents having an aziridine group), etc.

[0321] The crosslinking agent (F) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds.

[0322] When using the crosslinking agent (F), relative to the content of 100 parts by mass of the polymer component (A), the content of the crosslinking agent (F) in the composition (III-1) is preferably 0.01 to 20 parts by mass, more preferably 0.1 to 10 parts by mass, and particularly preferably 0.5 to 5 parts by mass. By making the content of the crosslinking agent (F) above the lower limit value, the effects brought by using the crosslinking agent (F) can be obtained more significantly. In addition, by making the content of the crosslinking agent (F) below the upper limit value, the excessive use of the crosslinking agent (F) can be suppressed.

[0323] [Energy ray curable resin (G)]

[0324] The composition (III-1) and the film for forming a thermosetting protective film may also contain an energy ray curable resin (G). By including the energy ray curable resin (G) in the film for forming a thermosetting protective film, the properties can be changed by irradiating energy rays.

[0325] The energy ray curable resin (G) is obtained by polymerizing (curing) an energy ray curable compound.

[0326] Examples of the energy ray curable compound include compounds having at least one polymerizable double bond in the molecule, and acrylate compounds having a (meth)acryloyl group are preferred.

[0327] Examples of the acrylate compounds include (meth)acrylates having a linear aliphatic skeleton such as trimethylolpropane tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxy penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate; (meth)acrylates having a cyclic aliphatic skeleton such as dicyclopentyl (meth)acrylate; polyalkylene glycol (meth)acrylates such as polyethylene glycol di(meth)acrylate; low polyester (meth)acrylates; urethane (meth)acrylate oligomers; epoxy modified (meth)acrylates; polyether (meth)acrylates other than the polyalkylene glycol (meth)acrylates; itaconic acid oligomers, etc.

[0328] The weight average molecular weight of the energy ray curable compound is preferably 100 to 30,000, more preferably 300 to 10,000.

[0329] The energy ray curable compound used for polymerization may be only one kind or two or more kinds.

[0330] The energy ray curable resin (G) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds.

[0331] When using the energy ray curable resin (G), in the composition (III-1), the content ratio of the energy ray curable resin (G) relative to the total mass of the composition (III-1) is preferably 1 to 95% by mass, more preferably 5 to 90% by mass, and particularly preferably 10 to 85% by mass.

[0332] [Photoinitiator (H)]

[0333] When the composition (III-1) and the film for forming a thermosetting protective film contain an energy ray-curable resin (G), a photopolymerization initiator (H) may be contained in order to efficiently promote the polymerization reaction of the energy ray-curable resin (G).

[0334] Examples of the photopolymerization initiator (H) in the composition (III-1) include the same photopolymerization initiators as those that can be contained in the above adhesive composition.

[0335] The photopolymerization initiator (H) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind, or two or more kinds.

[0336] When the photopolymerization initiator (H) is used, in the composition (III-1), relative to the content of 100 parts by mass of the energy ray-curable resin (G), the content of the photopolymerization initiator (H) is preferably 0.1 to 20 parts by mass, more preferably 1 to 10 parts by mass, and particularly preferably 2 to 5 parts by mass.

[0337] [Colorant (I)]

[0338] The composition (III-1) and the film for forming a thermosetting protective film may contain a colorant (I). By using the colorant (I), it is possible to more easily adjust the light transmittance of the film for forming a protective film and the protective film.

[0339] Examples of the colorant (I) include known colorants such as inorganic pigments, organic pigments, and organic dyes.

[0340] Examples of the organic pigments and organic dyes include aminium pigments, cyanine pigments, merocyanine pigments, croconium pigments, squarylium pigments, azulenium pigments, polymethine pigments, naphthoquinone pigments, pyranium pigments, phthalocyanine pigments, naphthalocyanine pigments, naphtholactam pigments, azo pigments, condensed azo pigments, indigo pigments, perinone pigments, perylene pigments, dioxazine pigments, quinacridone pigments, isoindolinone pigments, quinophthalone pigments, pyrrole pigments, thioindigo pigments, metal complex pigments (metal complex salts dyes), dithiol metal complex pigments, indophenol pigments, triarylmethane pigments, anthraquinone pigments, naphthol pigments, methineimine pigments, benzimidazolone pigments, perinone pigments, and threne pigments.

[0341] Examples of the inorganic pigments include carbon black, cobalt pigments, iron pigments, chromium pigments, titanium pigments, vanadium pigments, zirconium pigments, molybdenum pigments, ruthenium pigments, platinum pigments, ITO (indium tin oxide) pigments, ATO (antimony tin oxide) pigments, and the like.

[0342] The colorant (I) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds.

[0343] When using the colorant (I), the content of the colorant (I) in the film for forming a thermosetting protective film may be appropriately adjusted according to the purpose. For example, when adjusting the light transmittance of the film for forming a thermosetting protective film and the protective film, in the composition (III-1), the proportion of the content of the colorant (I) relative to the total content of all components except the solvent (that is, the proportion of the content of the colorant (I) in the film for forming a thermosetting protective film relative to the total mass of the film for forming a thermosetting protective film) is any range of 0.05 to 12% by mass, 0.05 to 9% by mass, and 0.1 to 7% by mass. By making the said proportion be above the lower limit value, the effect brought by using the colorant (I) can be obtained more significantly. In addition, by making the said proportion be below the upper limit value, the excessive use of the colorant (I) can be suppressed.

[0344] [General Additive (J)]

[0345] The composition (III-1) and the film for forming a thermosetting protective film may contain the general additive (J) within the range that does not impair the effects of the present invention.

[0346] The general additive (J) may be a known additive, which can be arbitrarily selected according to the purpose and is not particularly limited. Examples of preferred additives include plasticizers, antistatic agents, antioxidants, gettering agents, ultraviolet absorbers, and the like.

[0347] The general additive (J) contained in the composition (III-1) and the film for forming a thermosetting protective film may be only one kind or two or more kinds.

[0348] The content of the general additive (J) in the composition (III-1) and the film for forming a thermosetting protective film is not particularly limited and can be appropriately selected according to the purpose.

[0349] [Solvent]

[0350] Preferably, the composition (III-1) further contains a solvent. The composition (III-1) containing a solvent has good operability.

[0351] The solvent is not particularly limited. Preferred solvents include, for example, hydrocarbons such as toluene and xylene; alcohols such as methanol, ethanol, 2-propanol, isobutanol (2-methylpropan-1-ol), and 1-butanol; esters such as ethyl acetate; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran; amides (compounds having an amide bond) such as dimethylformamide and N-methylpyrrolidone, etc.

[0352] The solvent contained in the composition (III-1) can be only one kind or two or more kinds.

[0353] As a more preferred solvent contained in the composition (III-1), from the viewpoint of being able to more uniformly mix the components contained in the composition (III-1), for example, methyl ethyl ketone, toluene, ethyl acetate, etc. can be cited.

[0354] The content of the solvent of the composition (III-1) is not particularly limited, and can be appropriately selected according to the types of components other than the solvent, for example.

[0355] <Preparation method of thermosetting protective film-forming composition>

[0356] Thermosetting protective film-forming compositions such as the composition (III-1) can be obtained by blending the respective components for constituting it.

[0357] For example, except for the difference in the types of blended components, the thermosetting protective film-forming composition can be prepared by the same method as in the case of the adhesive composition described above.

[0358] ○ Film for forming energy ray-curable protective film

[0359] As long as the protective film has a degree of curing sufficient to fully exhibit its function, the curing conditions when the film for forming an energy ray-curable protective film is energy ray-cured to form a protective film are not particularly limited, and can be appropriately selected according to the type of the film for forming an energy ray-curable protective film.

[0360] For example, when the film for forming an energy ray-curable protective film is energy ray-cured, the illuminance of the energy ray is preferably 120 - 280 mW / cm 2 . And the light quantity of the energy ray during the curing is preferably 100 - 1000 mJ / cm 2 .

[0361] As the film for forming an energy ray-curable protective film, for example, a film for forming an energy ray-curable protective film containing the energy ray-curable component (a) can be cited, and a film for forming an energy ray-curable protective film preferably containing the energy ray-curable component (a) and a filler can be cited.

[0362] In the film for forming an energy ray-curable protective film, the energy ray-curable component (a) is preferably uncured, preferably has adhesiveness, and more preferably is uncured and has adhesiveness.

[0363] <Composition (IV-1) for forming an energy ray-curable protective film>

[0364] As a preferred composition for forming an energy ray-curable protective film, for example, there can be mentioned a composition (IV-1) for forming an energy ray-curable protective film containing the energy ray-curable component (a) (in this specification, sometimes simply abbreviated as "composition (IV-1)") and the like.

[0365] [Energy ray-curable component (a)]

[0366] The energy ray-curable component (a) is a component that is cured by irradiation with energy rays, and is also a component for imparting film-forming properties and flexibility, etc. to the film for forming an energy ray-curable protective film, and at the same time forms a hard protective film after curing.

[0367] As the energy ray-curable component (a), for example, there can be mentioned a polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80,000 to 2,000,000, and a compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80,000. At least a part of the polymer (a1) can be crosslinked by a crosslinking agent, or may not be crosslinked.

[0368] (Polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80,000 to 2,000,000)

[0369] As the polymer (a1) having an energy ray-curable group and a weight average molecular weight of 80,000 to 2,000,000, for example, there can be mentioned an acrylic resin (a1-1) obtained by reacting an acrylic polymer (a11) with an energy ray-curable compound (a12). The acrylic polymer (a11) has a functional group capable of reacting with a group possessed by other compounds, and the energy ray-curable compound (a12) has a group capable of reacting with the functional group and an energy ray-curable group such as an energy ray-curable double bond.

[0370] As the functional group capable of reacting with a group possessed by other compounds, for example, there can be mentioned a hydroxyl group, a carboxyl group, an amino group, a substituted amino group (a group in which one or two hydrogen atoms of the amino group are replaced by a group other than a hydrogen atom), an epoxy group, etc. However, in terms of preventing corrosion of the circuit of a semiconductor wafer or a semiconductor chip, it is preferred that the functional group is a group other than the carboxyl group.

[0371] Among them, it is preferred that the functional group is a hydroxyl group.

[0372] · Acrylic polymer (a11) having a functional group

[0373] As the acrylic polymer (a11) having a functional group, for example, a polymer copolymerized from an acrylic monomer having the functional group and an acrylic monomer not having the functional group can be cited. It can also be a polymer in which, in addition to these monomers, monomers other than acrylic monomers (non-acrylic monomers) are further copolymerized.

[0374] In addition, the acrylic polymer (a11) can be a random copolymer or a block copolymer, and the polymerization method can also adopt a known method.

[0375] As the acrylic monomer having the functional group, for example, a hydroxyl group-containing monomer, a carboxyl group-containing monomer, an amino group-containing monomer, a substituted amino group-containing monomer, an epoxy group-containing monomer, etc. can be cited.

[0376] As the hydroxyl group-containing monomer, for example, (meth)acrylic acid hydroxyalkyl esters such as hydroxyethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate; non-(meth)acrylic unsaturated alcohols such as vinyl alcohol and allyl alcohol (unsaturated alcohols without a (meth)acryloyl skeleton), etc.

[0377] As the carboxyl group-containing monomer, for example, olefinically unsaturated monocarboxylic acids such as (meth)acrylic acid and crotonic acid (monocarboxylic acids having an olefinically unsaturated bond); olefinically unsaturated dicarboxylic acids such as fumaric acid, itaconic acid, maleic acid, and citraconic acid (dicarboxylic acids having an olefinically unsaturated bond); anhydrides of the olefinically unsaturated dicarboxylic acids; (meth)acrylic acid carboxyalkyl esters such as 2-carboxyethyl methacrylate, etc.

[0378] It is preferred that the acrylic monomer having the functional group is a hydroxyl group-containing monomer.

[0379] The acrylic monomer having the functional group constituting the acrylic polymer (a11) can be only one kind or two or more kinds.

[0380] As the acrylic monomer not having the functional group, for example, (meth)acrylic acid alkyl esters in which the alkyl group constituting the alkyl ester has a linear structure with 1 to 18 carbon atoms can be cited.

[0381] In addition, as acrylic monomers that do not have the functional group, examples include (meth)acrylic acid methoxy methyl ester, (meth)acrylic acid methoxy ethyl ester, (meth)acrylic acid ethoxy methyl ester, (meth)acrylic acid ethoxy ethyl ester, and other (meth)acrylic acid esters containing alkoxyalkyl groups; (meth)acrylic acid esters having an aromatic group, including (meth)acrylic acid phenyl ester and other (meth)acrylic acid aryl esters; non-crosslinkable (meth)acrylamide and its derivatives; non-crosslinkable (meth)acrylic acid esters having a tertiary amino group, such as (meth)acrylic acid N,N-dimethylamino ethyl ester and (meth)acrylic acid N,N-dimethylamino propyl ester.

[0382] The acrylic monomer that does not have the functional group and constitutes the acrylic polymer (a11) may be only one kind, or two or more kinds.

[0383] As the non-acrylic monomer, examples include olefins such as ethylene and norbornene; vinyl acetate; styrene and the like.

[0384] The non-acrylic monomer that constitutes the acrylic polymer (a11) may be only one kind, or two or more kinds.

[0385] In the acrylic polymer (a11), the proportion (content) of the structural unit derived from the acrylic monomer having the functional group relative to the total amount of the structural units constituting the acrylic polymer (a11) is preferably 0.1 to 50% by mass, more preferably 1 to 40% by mass, and particularly preferably 3 to 30% by mass. By making the proportion within such a range, in the acrylic resin (a1-1) obtained by copolymerizing the acrylic polymer (a11) and the energy ray curable compound (a12), the content of the energy ray curable group can easily adjust the curing degree of the protective film to a preferred range.

[0386] The acrylic polymer (a11) that constitutes the acrylic resin (a1-1) may be only one kind, or two or more kinds.

[0387] In the composition (IV-1), the proportion of the content of the acrylic resin (a1-1) relative to the total content of the components other than the solvent (that is, the proportion of the content of the acrylic resin (a1-1) in the energy ray curable protective film forming film relative to the total mass of the film) is preferably 1 to 70% by mass, more preferably 5 to 60% by mass, and particularly preferably 10 to 50% by mass.

[0388] · Energy ray curable compound (a12)

[0389] Preferably, the energy ray curable compound (a12) has one or more groups selected from the group consisting of an isocyanate group, an epoxy group, and a carboxyl group as groups capable of reacting with the functional groups of the acrylic polymer (a11). More preferably, the energy ray curable compound (a12) has an isocyanate group as the group. For example, when the energy ray curable compound (a12) has an isocyanate group as the group, the isocyanate group easily reacts with the hydroxyl group of the acrylic polymer (a11) having a hydroxyl group as the functional group.

[0390] The number of the energy ray curable groups in one molecule of the energy ray curable compound (a12) is not particularly limited, and can be appropriately selected, for example, in consideration of physical properties such as the shrinkage rate desired for the target protective film.

[0391] For example, it is preferred that the energy ray curable compound (a12) has 1 to 5 of the energy ray curable groups in one molecule, and more preferably has 1 to 3 of the energy ray curable groups.

[0392] Examples of the energy ray curable compound (a12) include 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate, methacryloyl isocyanate, allyl isocyanate, 1,1-(bisacryloxymethyl)ethyl isocyanate;

[0393] acryloyl monoisocyanate compounds obtained by the reaction of a diisocyanate compound or a polyisocyanate compound with 2-hydroxyethyl (meth)acrylate;

[0394] acryloyl monoisocyanate compounds obtained by the reaction of a diisocyanate compound or a polyisocyanate compound with a polyol compound and 2-hydroxyethyl (meth)acrylate, etc.

[0395] Among them, it is preferred that the energy ray curable compound (a12) is 2-methacryloyloxyethyl isocyanate.

[0396] The energy ray curable compound (a12) constituting the acrylic resin (a1-1) may be only one kind, or two or more kinds.

[0397] In the acrylic resin (a1-1), the ratio of the content of the energy ray-curable group derived from the energy ray-curable compound (a12) to the content of the functional group derived from the acrylic polymer (a11) is preferably 20 to 120 mol%, more preferably 35 to 100 mol%, and particularly preferably 50 to 100 mol%. By setting the ratio of the content within such a range, the adhesive strength of the protective film becomes greater. In addition, when the energy ray-curable compound (a12) is a monofunctional compound (having one such group in one molecule), the upper limit value of the ratio of the content is 100 mol%, but when the energy ray-curable compound (a12) is a polyfunctional compound (having two or more such groups in one molecule), the upper limit value of the ratio of the content sometimes exceeds 100 mol%.

[0398] The weight-average molecular weight (M W ) of the polymer (a1) is preferably 100,000 to 2,000,000, more preferably 300,000 to 1,500,000.

[0399] Here, the "weight-average molecular weight" is the same as that described above.

[0400] When at least a part of the polymer (a1) is crosslinked by a crosslinking agent, the polymer (a1) may be a polymer obtained by polymerizing a monomer that does not belong to any of the above monomers described as monomers constituting the acrylic polymer (a11) and has a group that reacts with the crosslinking agent and is crosslinked at the group that reacts with the crosslinking agent, or may be a polymer crosslinked at a group that reacts with the functional group and is derived from the energy ray-curable compound (a12).

[0401] The polymer (a1) contained in the composition (IV-1) and the film for forming an energy ray-curable protective film may be only one kind or two or more kinds.

[0402] (Compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80,000)

[0403] Examples of the energy ray-curable group in the compound (a2) having an energy ray-curable group and a molecular weight of 100 to 80,000 include groups containing an energy ray-curable double bond, and preferred groups include (meth)acryloyl group, vinyl group, etc.

[0404] The compound (a2) is not particularly limited as long as it satisfies the above conditions, and examples thereof include low molecular weight compounds having an energy ray-curable group, epoxy resins having an energy ray-curable group, phenolic resins having an energy ray-curable group, etc.

[0405] Examples of the low molecular weight compound having an energy ray curable group in the compound (a2) include polyfunctional monomers or oligomers, etc., and acrylate compounds having a (meth)acryloyl group are preferred.

[0406] Examples of the acrylate compounds include 2-hydroxy-3-(meth)acryloyloxypropyl methacrylate, polyethylene glycol di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloyloxypolyethoxy)phenyl]propane, ethoxylated bisphenol A di(meth)acrylate, 2,2-bis[4-((meth)acryloyloxydiethoxy)phenyl]propane, 9,9-bis[4-(2-(meth)acryloyloxyethoxy)phenyl]fluorene, 2,2-bis[4-((meth)acryloyloxypolypropoxy)phenyl]propane, tricyclodecane dimethanol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polytetramethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, 2,2-bis[4-((meth)acryloyloxyethoxy)phenyl]propane, neopentyl glycol di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, 2-hydroxy-1,3-di(meth)acryloyloxypropane and other difunctional (meth)acrylates;

[0407] Tris(2-(meth)acryloyloxyethyl) isocyanurate, ε-caprolactone modified tris(2-(meth)acryloyloxyethyl) isocyanurate, ethoxylated glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol poly(meth)acrylate, dipentaerythritol hexa(meth)acrylate and other polyfunctional (meth)acrylates;

[0408] Polyfunctional (meth)acrylate oligomers such as urethane (meth)acrylate oligomers, etc.

[0409] As the epoxy resin having an energy ray curable group and the phenol resin having an energy ray curable group in the compound (a2), for example, the resins described in paragraph 0043 of "Japanese Patent Laid-Open No. 2013-194102" can be used. Such resins also belong to the resins constituting the thermosetting component described later, but in the present invention, they are regarded as the compound (a2).

[0410] The weight average molecular weight of the compound (a2) is preferably 100 to 30,000, more preferably 300 to 10,000.

[0411] The compound (a2) contained in the composition (IV-1) and the film for forming an energy ray curable protective film may be only one kind, or two or more kinds.

[0412] [Polymer (b) not having an energy ray curable group]

[0413] When the composition (IV-1) and the film for forming an energy ray curable protective film contain the compound (a2) as the energy ray curable component (a), it is preferable to further contain a polymer (b) not having an energy ray curable group.

[0414] The polymer (b) may be a substance crosslinked at least in part by a crosslinking agent, or may be an uncrosslinked substance.

[0415] Examples of the polymer (b) not having an energy ray curable group include acrylic polymers, phenoxy resins, urethane resins, polyesters, rubber-like resins, acrylic urethane resins, and the like.

[0416] Among them, it is preferable that the polymer (b) is an acrylic polymer (hereinafter, sometimes simply written as "acrylic polymer (b-1)").

[0417] The acrylic polymer (b-1) may be a known acrylic polymer. For example, it may be a homopolymer of one acrylic monomer, a copolymer of two or more acrylic monomers, or a copolymer of one or two or more acrylic monomers and one or two or more monomers other than acrylic monomers (non-acrylic monomers).

[0418] Examples of the acrylic monomer constituting the acrylic polymer (b-1) include (meth)acrylic acid alkyl esters, (meth)acrylates having a cyclic skeleton, (meth)acrylates containing a glycidyl group, (meth)acrylates containing a hydroxyl group, (meth)acrylates containing a substituted amino group, and the like. Here, "substituted amino" is the same as that described above.

[0419] Examples of the (meth)acrylic acid alkyl ester include the same substances as the acrylic monomers that do not have the functional group and constitute the acrylic polymer (a11) described above (such as (meth)acrylic acid alkyl esters in which the alkyl group constituting the alkyl ester has a linear structure with 1 to 18 carbon atoms).

[0420] Examples of the (meth)acrylic acid ester having a cyclic skeleton include (meth)acrylic acid cycloalkyl esters such as isobornyl (meth)acrylate and dicyclopentyl (meth)acrylate;

[0421] (meth)acrylic acid aralkyl esters such as benzyl (meth)acrylate;

[0422] (meth)acrylic acid cycloalkenyl esters such as dicyclopentenyl (meth)acrylate;

[0423] (meth)acrylic acid cycloalkenyloxyalkyl esters such as dicyclopentenyl oxyethyl (meth)acrylate, etc.

[0424] Examples of the (meth)acrylic acid ester containing a glycidyl group include glycidyl (meth)acrylate, etc.

[0425] Examples of the (meth)acrylic acid ester containing a hydroxyl group include methyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, etc.

[0426] Examples of the (meth)acrylic acid ester containing a substituted amino group include N-methylethylamino (meth)acrylate, etc.

[0427] Examples of the non-acrylic monomers constituting the acrylic polymer (b-1) include olefins such as ethylene and norbornene; vinyl acetate; styrene, etc.

[0428] Examples of the polymer (b) that is at least partially crosslinked by a crosslinking agent and does not have an energy ray curable group include polymers obtained by reacting the reactive functional groups in the polymer (b) with a crosslinking agent.

[0429] The reactive functional group can be appropriately selected according to the type of the crosslinking agent or the like, and there is no particular limitation. For example, when the crosslinking agent is a polyisocyanate compound, examples of the reactive functional group include a hydroxyl group, a carboxyl group, an amino group, etc. Among them, a hydroxyl group having a high reactivity with an isocyanate group is preferred. In addition, when the crosslinking agent is an epoxy compound, examples of the reactive functional group include a carboxyl group, an amino group, an amide group, etc. Among them, a carboxyl group having a high reactivity with an epoxy group is preferred. However, in terms of preventing corrosion of the circuits of a semiconductor wafer or a semiconductor chip, it is preferred that the reactive functional group be a group other than a carboxyl group.

[0430] Examples of the polymer (b) having the reactive functional group and not having an energy ray curable group include a polymer obtained by polymerizing at least a monomer having the reactive functional group. When the polymer (b) is an acrylic polymer (b-1), it is sufficient to use, as the monomer having the reactive functional group, any one or both of the acrylic monomers and non-acrylic monomers listed as the monomers constituting the acrylic polymer (b-1). Examples of the polymer (b) having a hydroxyl group as the reactive functional group include a polymer obtained by polymerizing a hydroxyl group-containing (meth)acrylate. In addition, examples include a polymer obtained by polymerizing a monomer in which one or more hydrogen atoms of the acrylic monomers or non-acrylic monomers listed above are substituted with the reactive functional group.

[0431] In the polymer (b) having a reactive functional group, the proportion (content) of the structural unit derived from the monomer having the reactive functional group relative to the total amount of the structural units constituting it is preferably 1 to 20% by mass, more preferably 2 to 10% by mass. By making the proportion within such a range, the degree of crosslinking in the polymer (b) becomes a more preferable range.

[0432] From the viewpoint of making the film-forming property of the composition (IV-1) better, it is preferred that the weight average molecular weight (M W ) of the polymer (b) not having an energy ray curable group is 10,000 to 2,000,000, more preferably 100,000 to 1,500,000. Here, the "weight average molecular weight" is the same as that described above.

[0433] The polymer (b) not having an energy ray curable group contained in the composition (IV-1) and the energy ray curable protective film-forming film may be only one kind or two or more kinds.

[0434] As the composition (IV-1), a composition containing any one or both of the polymer (a1) and the compound (a2) can be cited. And when the composition (IV-1) contains the compound (a2), it preferably further contains a polymer (b) not having an energy ray curable group, and in this case, it also preferably further contains the (a1). In addition, the composition (IV-1) may not contain the compound (a2) and contain both the polymer (a1) and the polymer (b) not having an energy ray curable group at the same time.

[0435] When the composition (IV-1) contains the polymer (a1), the compound (a2), and the polymer (b) not having an energy ray curable group, in the composition (IV-1), with respect to the total content of 100 parts by mass of the polymer (a1) and the polymer (b) not having an energy ray curable group, the content of the compound (a2) is preferably 10 to 400 parts by mass, more preferably 30 to 350 parts by mass.

[0436] In the composition (IV-1), the ratio of the total content of the energy ray curable component (a) and the polymer (b) not having an energy ray curable group to the total content of the components other than the solvent (that is, the ratio of the total content of the energy ray curable component (a) and the polymer (b) not having an energy ray curable group to the total mass of the film in the energy ray curable protective film forming film) is preferably 5 to 90% by mass, more preferably 10 to 80% by mass, and particularly preferably 20 to 70% by mass. By making the ratio of the content of the energy ray curable component within such a range, the energy ray curability of the energy ray curable protective film forming film becomes better.

[0437] In addition to containing the energy ray curable component, the composition (IV-1) may contain one or more selected from the group consisting of a thermosetting component, a filler, a coupling agent, a crosslinking agent, a photoinitiator, a colorant, and a general additive according to the purpose.

[0438] As the thermosetting component, filler, coupling agent, crosslinking agent, photoinitiator, colorant, and general additive in the composition (IV-1), the same substances as the thermosetting component (B), filler (D), coupling agent (E), crosslinking agent (F), photoinitiator (H), colorant (I), and general additive (J) in the composition (III-1) can be cited respectively.

[0439] For example, by using the composition (IV-1) containing the energy ray curable component and the thermosetting component, the adhesion of the film for forming an energy ray curable protective film to the adherend is increased by heating, and the strength of the protective film formed from the film for forming an energy ray curable protective film is also increased.

[0440] In addition, by using the composition (IV-1) containing the energy ray curable component and the colorant, the film for forming an energy ray curable protective film exhibits the same effects as those of the film for forming a thermosetting protective film containing the colorant (I) described above.

[0441] In the composition (IV-1), the thermosetting component, the filler, the coupling agent, the crosslinking agent, the photoinitiator, the colorant, and the general additive can each be used alone or two or more of them can be used simultaneously.

[0442] According to the purpose, the contents of the thermosetting component, the filler, the coupling agent, the crosslinking agent, the photoinitiator, the colorant, and the general additive in the composition (IV-1) can be appropriately adjusted, and there is no particular limitation.

[0443] Since the workability of the composition (IV-1) is improved by dilution, it is preferably further contained a solvent.

[0444] As the solvent contained in the composition (IV-1), for example, the same solvents as those in the composition (III-1) can be cited.

[0445] The solvent contained in the composition (IV-1) can be only one kind or two or more kinds.

[0446] <Preparation method of the composition for forming an energy ray curable protective film>

[0447] The composition for forming an energy ray curable protective film such as the composition (IV-1) can be obtained by blending the respective components for constituting it.

[0448] For example, except for the difference in the types of the blended components, the composition for forming an energy ray curable protective film can be prepared by the same method as that of the adhesive composition described above.

[0449] ○ Film for forming a non-curable protective film

[0450] As a preferable film for forming a non-curable protective film, for example, a film for forming a non-curable protective film containing a thermoplastic resin and a filler can be cited.

[0451] <Composition (V-1) for forming a non-curable protective film>

[0452] As a preferred non-curing protective film-forming composition, for example, there can be mentioned a non-curing protective film-forming composition (V-1) containing the above-mentioned thermoplastic resin and a filler (in this specification, sometimes simply written as "composition (V-1)") and the like.

[0453] [Thermoplastic resin]

[0454] The thermoplastic resin is not particularly limited.

[0455] More specifically, as the thermoplastic resin, for example, there can be mentioned the same resins as the acrylic resin, polyester, polyurethane, phenoxy resin, polybutene, polybutadiene, polystyrene, etc. which are non-curing resins listed as the components of the above-mentioned composition (III-1).

[0456] The thermoplastic resin contained in the composition (V-1) and the non-curing protective film-forming film may be only one kind, or two or more kinds.

[0457] In the composition (V-1), the proportion of the content of the thermoplastic resin relative to the total content of the components other than the solvent (that is, the proportion of the content of the thermoplastic resin in the non-curing protective film-forming film relative to the total mass of the non-curing protective film-forming film) is preferably 25 to 75% by mass.

[0458] [Filler]

[0459] The non-curing protective film-forming film containing a filler exhibits the same effect as the thermosetting protective film-forming film containing the filler (D).

[0460] As the filler contained in the composition (V-1) and the non-curing protective film-forming film, there can be mentioned the same fillers as the filler (D) contained in the composition (III-1) and the thermosetting protective film-forming film.

[0461] The filler contained in the composition (V-1) and the non-curing protective film-forming film may be only one kind, or two or more kinds.

[0462] In the composition (V-1), the proportion of the content of the filler relative to the total content of all components other than the solvent (that is, the proportion of the content of the filler in the non-curing protective film-forming film relative to the total mass of the non-curing protective film-forming film) is preferably 25 to 75% by mass. By making the proportion within such a range, the adjustment of the coefficient of thermal expansion of the non-curing protective film-forming film (that is, the protective film) becomes easier, similar to the case of using the composition (III-1).

[0463] In addition to containing the thermoplastic resin and the filler, the composition (V-1) may further contain other components according to the purpose.

[0464] For example, by using the composition (V-1) containing a colorant as the other component, the formed uncured protective film-forming film (in other words, the protective film) exhibits the same effect as the thermosetting protective film-forming film containing the colorant (I) described above.

[0465] In the composition (V-1), the other components may be used alone or in combination of two or more.

[0466] The content of the other components of the composition (V-1) can be appropriately adjusted according to the purpose and is not particularly limited.

[0467] Since the operability of the composition (V-1) is improved by dilution, it is preferably further contained with a solvent.

[0468] As the solvent contained in the composition (V-1), for example, the same solvents as those in the above composition (III-1) can be cited.

[0469] The solvent contained in the composition (V-1) may be only one kind or two or more kinds.

[0470] <Preparation method of uncured protective film-forming composition>

[0471] The uncured protective film-forming composition such as the composition (V-1) can be obtained by blending the respective components for constituting it.

[0472] For example, except for the difference in the types of blended components, the uncured protective film-forming composition can be prepared by the same method as in the case of the adhesive composition described above.

[0473] ◎ Release film

[0474] The release film can be a known release film.

[0475] As the release film, for example, the same film as the above-described peelability-improving layer can be cited, that is, a multi-layered release film composed of a resin layer and a release treatment layer formed on the resin layer.

[0476] The thickness of the release film (the total thickness of the resin layer and the release treatment layer) is preferably 10 to 200 μm, more preferably 15 to 150 μm, and particularly preferably 20 to 100 μm. By making the thickness of the release film not less than the lower limit value, the effect of suppressing breakage such as cutting of the release film becomes higher. By making the thickness of the release film not more than the upper limit value, excessive thickness can be avoided.

[0477] In this specification, as long as the laminated structure of the support sheet and the cured product (e.g., protective film) of the film for forming the protective film is maintained, even after curing the film for forming the protective film, the laminated structure is referred to as a "composite sheet for forming a protective film".

[0478] Within the scope that does not impair the effects of the present invention, the composite sheet for forming a protective film may also include other layers that do not belong to any of the substrate, adhesive layer, intermediate layer, film for forming a protective film, and release film.

[0479] The type of the other layer is not particularly limited and can be arbitrarily selected according to the purpose.

[0480] The arrangement position, shape, size, etc. of the other layer can also be arbitrarily selected according to its type and are not particularly limited.

[0481] The thickness of the semiconductor wafer, which is the object of use of the composite sheet for forming a protective film, is not particularly limited. In terms of being more easily divided into semiconductor chips described later, it is preferably 30 to 700 μm, and for example, it can be 50 to 200 μm.

[0482] As an example of a preferred composite sheet roll for forming a protective film of the present embodiment, there can be cited a composite sheet roll for forming a protective film, which is formed by winding the composite sheet for forming a protective film into a roll shape. Among them,

[0483] The composite sheet for forming a protective film includes a support sheet, a film for forming a protective film provided on one surface of the support sheet, and a release film provided on the surface of the film for forming a protective film opposite to the support sheet side.

[0484] The composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface in the radial direction of the roll.

[0485] The thickness of the composite sheet for forming a protective film is 100 to 200 μm.

[0486] The length in the long side direction of the composite sheet for forming a protective film is 10 to 100 m.

[0487] The composite sheet roll for forming a protective film is formed by winding the composite sheet for forming a protective film along its long side direction.

[0488] The outer diameter of the composite sheet roll for forming a protective film is 100 to 300 mm.

[0489] As another example of the preferred composite sheet roll for forming a protective film according to this embodiment, there can be cited a composite sheet roll for forming a protective film, which is formed by winding a composite sheet for forming a protective film into a roll shape. Among them,

[0490] The composite sheet for forming a protective film includes a support sheet, a film for forming a protective film provided on one surface of the support sheet, and a release film provided on the surface of the film for forming a protective film opposite to the support sheet side.

[0491] The composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface in the radial direction of the roll.

[0492] The support sheet includes a base material and an adhesive layer provided on one surface of the base material, and the adhesive layer is disposed between the base material and the film for forming a protective film.

[0493] The constituent material of the base material is polyolefin.

[0494] The release film includes a resin layer made of polyester as a constituent material.

[0495] As another example of the preferred composite sheet roll for forming a protective film according to this embodiment, there can be cited a composite sheet roll for forming a protective film, which is formed by winding a composite sheet for forming a protective film into a roll shape. Among them,

[0496] The composite sheet for forming a protective film includes a support sheet, a film for forming a protective film provided on one surface of the support sheet, and a release film provided on the surface of the film for forming a protective film opposite to the support sheet side.

[0497] The composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface in the radial direction of the roll.

[0498] The thickness of the composite sheet for forming a protective film is 100 to 200 μm.

[0499] The length of the composite sheet for forming a protective film in the long side direction is 10 to 100 m.

[0500] The composite sheet roll for forming a protective film is formed by winding the composite sheet for forming a protective film along its long side direction.

[0501] The outer diameter of the composite sheet roll for forming a protective film is 100 to 300 mm.

[0502] The support sheet includes a base material and an adhesive layer provided on one surface of the base material, and the adhesive layer is disposed between the base material and the film for forming a protective film.

[0503] The constituent material of the base material is polyolefin.

[0504] The release film includes a resin layer made of polyester as a constituent material.

[0505] As another example of the preferred composite sheet roll for forming a protective film in the present embodiment, there can be cited a composite sheet roll for forming a protective film, which is formed by winding the composite sheet for forming a protective film into a roll shape. Among them,

[0506] The composite sheet for forming a protective film includes a support sheet, a film for forming a protective film provided on one surface of the support sheet, and a release film provided on the surface of the film for forming a protective film opposite to the support sheet side.

[0507] The composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the radial direction of the roll is the outermost surface on the release film side of the composite sheet for forming a protective film.

[0508] The support sheet includes a base material and an adhesive layer provided on one surface of the base material, and the adhesive layer is disposed between the base material and the film for forming a protective film.

[0509] The base material contains an antistatic agent or has an antistatic coating.

[0510] When the composite sheet for forming a protective film is unwound from the composite sheet roll for forming a protective film and the static voltage of the outermost surface on the release film side of the composite sheet for forming a protective film is immediately measured, the static voltage is 1.0 kV or less.

[0511] ◇ Manufacturing method of the composite sheet roll for forming a protective film

[0512] Hereinafter, the manufacturing method of the composite sheet roll for forming a protective film will be described.

[0513] First, the manufacturing method of the composite sheet for forming a protective film formed into a roll will be described.

[0514] By laminating the above respective layers in a corresponding positional relationship and adjusting the shape of a part or all of the layers as needed, the composite sheet for forming a protective film can be manufactured. The formation method of each layer is the same as that described above.

[0515] For example, when manufacturing the support sheet, when laminating the adhesive layer on the base material, the above adhesive composition is applied to the base material and dried as needed.

[0516] In addition, even by applying the pressure-sensitive adhesive composition onto the release film and drying it as needed to form a pressure-sensitive adhesive layer on the release film, and then bonding the exposed surface of the pressure-sensitive adhesive layer to one surface of the substrate, the pressure-sensitive adhesive layer can be laminated on the substrate. At this time, it is preferable to apply the pressure-sensitive adhesive composition onto the release-treated surface of the release film.

[0517] So far, the case of laminating a pressure-sensitive adhesive layer on a substrate has been exemplified, but the above method can also be applied, for example, to the case of laminating an intermediate layer or the other layer on a substrate.

[0518] On the other hand, for example, when further laminating a film for forming a protective film on a pressure-sensitive adhesive layer that has been laminated on a substrate, the composition for forming the protective film can be applied onto the pressure-sensitive adhesive layer to directly form the film for forming the protective film. For layers other than the film for forming the protective film, the same method can be used, and the layer can be laminated on the pressure-sensitive adhesive layer by using the composition for forming the layer. Thus, when forming a new layer (hereinafter simply referred to as "the second layer") on an arbitrary layer (hereinafter simply referred to as "the first layer") that has been laminated on a substrate to form a laminated structure of two consecutive layers (in other words, the laminated structure of the first layer and the second layer), the method of applying the composition for forming the second layer onto the first layer and drying it as needed can be applied.

[0519] Among them, it is preferable to pre-form the second layer on the release film by using the composition for forming the second layer, and bond the exposed surface of the formed second layer on the side opposite to the side in contact with the release film to the exposed surface of the first layer, thereby forming a laminated structure of two consecutive layers. At this time, it is preferable to apply the composition onto the release-treated surface of the release film. After forming the laminated structure, the release film can be removed as needed.

[0520] Although the case of laminating a film for forming a protective film on a pressure-sensitive adhesive layer has been exemplified here, for the target laminated structure, for example, the case of laminating an intermediate layer or the other layer on a pressure-sensitive adhesive layer can be arbitrarily selected.

[0521] Thus, since the layers other than the substrate constituting the composite sheet for forming a protective film can be pre-formed on the release film and laminated by bonding to the surface of the target layer, it is only necessary to appropriately select the layers using this process as needed to manufacture the composite sheet for forming a protective film.

[0522] The release film described in the above description of the manufacturing method does not necessarily have to be the release film itself constituting the composite sheet for forming a protective film, and it can be adjusted so that the finally obtained composite sheet for forming a protective film has the target release film.

[0523] Among them, when a composition for forming a protective film or the like, which is a composition for forming a layer constituting the outermost layer, is applied and dried as needed, a layer constituting the outermost layer is formed on the release film, and each of the other layers is laminated on the exposed surface on the side opposite to the side in contact with the release film of this layer by any of the above methods, so as to manufacture a composite sheet for forming a protective film. Even when the composition for forming a layer constituting the outermost layer is applied to the release film itself of the composite sheet for forming a protective film of the present embodiment and the state where the release film is adhered without being removed is maintained, the composite sheet for forming a protective film can be obtained.

[0524] Next, a method for manufacturing a roll of the composite sheet for forming a protective film of the present embodiment will be described.

[0525] The composite sheet for forming a protective film can be wound into a roll in such a manner that the outermost surface on the release film side of the composite sheet for forming a protective film is the outermost surface in the radial direction of the roll, thereby manufacturing a roll of the composite sheet for forming a protective film of the present embodiment. The winding direction of the composite sheet for forming a protective film at this time is the same as that described above.

[0526] When the composite sheet for forming a protective film is a long rectangle, it is preferable that the long side direction of the composite sheet for forming a protective film is the winding direction.

[0527] When winding the composite sheet for forming a protective film, it is preferable to wind it in such a manner that no gap is generated between the laminated composite sheets for forming a protective film (more specifically, between the outermost layer on the release film side of one composite sheet for forming a protective film and the outermost layer on the support sheet side of another composite sheet for forming a protective film), and these composite sheets for forming a protective film are in a closely adhered state to each other.

[0528] ◇ Method of using the roll of the composite sheet for forming a protective film (method of manufacturing a semiconductor chip with a protective film)

[0529] When manufacturing a semiconductor chip with a protective film, the roll of the composite sheet for forming a protective film of the present embodiment can be used in the same manner as in the case of a known roll of the composite sheet for forming a protective film. An example of the method of using the roll is shown below.

[0530] That is, first, before using the composite sheet for forming a protective film, a semiconductor wafer is divided into semiconductor chips, or the semiconductor wafer is processed into a state where it can be easily divided into semiconductor chips. The division or processing at this time can be performed, for example, by laser stealth dicing (registered trademark).

[0531] Laser stealth dicing (registered trademark) refers to the method described below. That is, first, a dicing predetermined position is set inside the semiconductor wafer, and with this position as the focus, laser is irradiated in a manner focused on this focus, thereby forming a modified layer inside the semiconductor wafer. The modified layer of the semiconductor wafer is different from other positions of the semiconductor wafer. It will be modified due to the irradiation of the laser, and its strength will become weak. Therefore, by applying a force to the semiconductor wafer, cracks extending in the direction of both sides of the semiconductor wafer will be generated at the modified layer inside the semiconductor wafer, serving as the starting point for the dicing (cutting) of the semiconductor wafer.

[0532] Next, by applying a force to the semiconductor wafer, the semiconductor wafer is diced at the position of the modified layer to fabricate semiconductor chips, or the semiconductor wafer is not diced and remains in its original state. Sometimes, the back surface of the semiconductor wafer is polished to adjust the thickness. At this time, a force is applied to the semiconductor wafer due to the polishing means. Therefore, by polishing the back surface of the semiconductor wafer after the modified layer is formed and using the force at this time, the semiconductor wafer can be diced. In addition, when polishing the back surface of the semiconductor wafer, a back grinding tape is usually attached to the circuit formation surface of the semiconductor wafer.

[0533] When the dicing of the semiconductor wafer into semiconductor chips is completed by applying a force to the semiconductor wafer, a semiconductor chip group in which the semiconductor chips are arranged uniformly and neatly can be obtained. When the dicing of the semiconductor wafer into semiconductor chips is not completed, a semiconductor chip group with an un-diced area where a part of the semiconductor wafer remains un-diced can be obtained. When using the said roll, a part of the semiconductor wafer can also be not diced like this. In this specification, a semiconductor chip group with an un-diced area is regarded as being included in the semiconductor chip group.

[0534] It can be considered that such an un-diced area and the semiconductor wafer in which the above-mentioned modified layer is formed but not diced are both the above-mentioned "semiconductor wafers in a state that can be easily diced into semiconductor chips".

[0535] Next, a film for forming a protective film in the composite sheet for forming a protective film is attached to the back surface of the semiconductor chip group, or to the back surface of the semiconductor wafer in which the modified layer is formed but not diced.

[0536] At this time, when the composite sheet for forming a protective film is wound into a roll shape, the composite sheet for forming a protective film unwound from the roll is used.

[0537] Next, in a state where the composite sheet for forming a protective film in a state of being attached to a semiconductor chip group or a semiconductor wafer is cooled, a so-called cold expansion is performed in a direction parallel to its surface. When performing cold expansion, the composite sheet for forming a protective film is usually disposed on a stage (a so-called expansion stage) and performed. Thus, when the composite sheet for forming a protective film is attached to the semiconductor chip group, the protective film forming film or the protective film in the composite sheet for forming a protective film is cut at a position along the outer periphery of the semiconductor chip. When using the semiconductor chip group having the undivided region, by applying the force during cold expansion to the undivided region, the semiconductor wafer is divided in the undivided region to manufacture a semiconductor chip, and at the same time, the protective film forming film or the protective film in the composite sheet for forming a protective film is cut along the division position of the semiconductor wafer at this time. On the other hand, when the composite sheet for forming a protective film is attached to the semiconductor wafer, by applying the force during cold expansion to the semiconductor wafer, the semiconductor wafer is divided at the position of the modified layer to manufacture a semiconductor chip, and at the same time, the protective film forming film or the protective film in the composite sheet for forming a protective film is cut along the division position of the semiconductor wafer at this time.

[0538] Next, the semiconductor chip having the cut protective film forming film or protective film on the back surface is separated from the support sheet and picked up.

[0539] When the protective film forming film is curable, the protective film forming film may be cured (i.e., the protective film is formed) at an arbitrary timing as needed. When the protective film forming film is non-curable, the protective film forming film after being attached to the back surface of the semiconductor chip group or the semiconductor wafer is regarded as the protective film.

[0540] In the above manner, a semiconductor chip with a protective film can be obtained, which is composed of a semiconductor chip and a protective film provided on its back surface.

[0541] Embodiment

[0542] Hereinafter, the present invention will be described in more detail based on specific embodiments. However, the present invention is not limited by any of the following embodiments.

[0543] <Manufacturing raw materials of resin>

[0544] The following shows the official names of the manufacturing raw materials of the resin abbreviated in the present embodiment and the comparative example.

[0545] MA: Methyl acrylate

[0546] HEA: 2-Hydroxyethyl acrylate

[0547] 2EHA: 2-Ethylhexyl acrylate

[0548] MOI: 2-Methacryloyloxyethyl isocyanate

[0549] <Raw materials for preparing the composition for forming a protective film>

[0550] The raw materials for preparing the composition for forming a protective film are shown below.

[0551] [Polymer component (A)]

[0552] (A)-1: An acrylic polymer copolymerized from MA (85 parts by mass) and HEA (15 parts by mass) (weight average molecular weight 370,000, glass transition temperature 6°C).

[0553] [Thermosetting component (B1)]

[0554] (B1)-1: A mixture of a liquid bisphenol A type epoxy resin and acrylic rubber fine particles ("BPA328" manufactured by NIPPON SHOKUBAI CO., LTD., epoxy equivalent 235 g / eq)

[0555] (B1)-2: A solid bisphenol A type epoxy resin ("jER1055" manufactured by Mitsubishi Chemical Corporation, molecular weight 1600, softening point 93°C, epoxy equivalent 800 - 900 g / eq)

[0556] (B1)-3: A dicyclopentadiene type epoxy resin ("EPICLON HP-7200HH" manufactured by DIC CORPORATION, epoxy equivalent 255 - 260 g / eq)

[0557] [Thermosetting curing agent (B2)]

[0558] (B2)-1: Dicyandiamide ("ADEKA HARDENER EH-3636AS" manufactured by ADEKA CORPORATION, a heat-active latent epoxy resin curing agent, active hydrogen equivalent 21 g / eq)

[0559] [Curing accelerator (C)]

[0560] (C)-1: 2-Phenyl-4,5-dihydroxymethylimidazole ("CUREZOL 2PHZ" manufactured by SHIKOKU CHEMICALS CORPORATION.)

[0561] [Filler (D)]

[0562] (D)-1: A silica filler ("SC2050MA" manufactured by Admatechs, a silica filler surface-modified with an epoxy compound, average particle size 0.5 μm)

[0563] [Coupling agent (E)]

[0564] (E)-1: 3-aminopropyltrimethoxysilane ("A-1110" manufactured by NUC CO., LTD.)

[0565] [Colorant (I)]

[0566] (I)-1: Black pigment prepared by mixing three organic pigments (manufactured by Dainichiseika Color&Chemicals Mfg. Co., Ltd.)

[0567] [Example 1]

[0568] "Manufacture of Composite Sheet Roll for Forming Protective Film"

[0569] <Manufacture of Support Sheet>

[0570] (Preparation of Adhesive Composition (I-4))

[0571] Prepare a non-energy ray curable adhesive composition (I-4)-1, which contains an adhesive resin (I-1a)-1 (100 parts by mass), bisphenol A type epoxy resin ("jER828" manufactured by Mitsubishi Chemical Corporation, molecular weight 370, epoxy equivalent 184 - 194 g / eq) (16 parts by mass), and a trifunctional xylylene diisocyanate crosslinking agent ("TAKENATE D110N" manufactured by Mitsui Takeda Chemical Co., Ltd.) (20 parts by mass), and further contains methyl ethyl ketone as a solvent, and the total concentration of all components except the solvent is 33% by mass. In addition, the content of the components shown here except methyl ethyl ketone is all the content of the target substance excluding the solvent. Further, the adhesive resin (I-1a)-1 is a copolymer of 2EHA (80 parts by mass) and HEA (20 parts by mass), and is an acrylic polymer with a weight average molecular weight of 600,000.

[0572] (Manufacture of Support Sheet)

[0573] Use a long strip release film ("SP-PET381031" manufactured by Lintec Corporation, thickness 38 μm) whose one side of the poly(ethylene terephthalate) film has been release-treated by silicone treatment, and coat the obtained adhesive composition (I-4)-1 on the release-treated surface of the long strip release film, and heat and dry at 100 °C for 2 minutes to thereby form a non-energy ray curable adhesive layer with a thickness of 5 μm.

[0574] Next, a long strip of polypropylene (PP) film (80 μm thick, colorless) as a base material was laminated on the exposed surface of the adhesive layer to produce a long laminated sheet in which the base material, the adhesive layer, and the release film were laminated in this order along their thickness directions, that is, a support sheet with a release film was produced.

[0575] Using a surface resistivity tester ("R12704 Resistivity chamber" manufactured by ADVANTEST CORPORATION), with the applied voltage set to 100 V, the surface resistivity of the polypropylene film was measured, and the result was 1.0×10 15 Ω / m 2 。

[0576] <Manufacture of the film for forming the protective film>

[0577] (Preparation of the composition (III-1) for forming the protective film)

[0578] By dissolving or dispersing the polymer component (A)-1 (150 parts by mass), the thermosetting component (B1)-1 (60 parts by mass), the thermosetting component (B1)-2 (10 parts by mass), the thermosetting component (B1)-3 (30 parts by mass), the thermosetting curing agent (B2)-1 (2.4 parts by mass), the curing accelerator (C)-1 (2.4 parts by mass), the filler (D)-1 (320 parts by mass), the coupling agent (E)-1 (2 parts by mass), and the colorant (I)-1 (3 parts by mass) in a mixed solvent of methyl ethyl ketone, toluene, and ethyl acetate, and stirring at 23°C, a thermosetting composition (III-1)-1 for forming a protective film with a total concentration of all components except the solvent of 45% by mass was obtained. In addition, the blending amounts of the components shown here except for the mixed solvent are all the blending amounts of the target substances not including the solvent.

[0579] <Manufacture of the film for forming the protective film>

[0580] A long release film ("SP-PET381031" manufactured by Lintec Corporation, 38 μm thick) obtained by subjecting one side of a polyethylene terephthalate (PET) film to a release treatment by silicone treatment was used, and the above-obtained composition (III-1)-1 for forming a protective film was coated on the release-treated surface of the long release film and dried at 100°C for 2 minutes to thereby form a long thermosetting film for forming a protective film with a thickness of 25 μm.

[0581] Furthermore, the above-obtained long film for forming a protective film was punched in such a planar shape that a plurality of circles with a diameter of 300 mm were arranged in a row along the long side direction of the release film.

[0582] In the above manner, a long laminated film composed of a release film having a long strip and a film for forming a circular protective film is obtained, and the circular films for forming the protective film are arranged in a row on one surface of the release film.

[0583] <Manufacture of Composite Sheet for Forming Protective Film>

[0584] Remove the release film from the obtained support sheet. Then, bond the exposed surface of the adhesive layer in the resulting support sheet to the exposed surface of the film for forming the protective film in the above laminated film.

[0585] Next, in order to form a circular region of the support sheet including the region where the film for forming the protective film is bonded, a punching process for removing a part of the support sheet (forming the notch) is performed. At this time, considering the size of the annular frame, the size of the circular support sheet is adjusted so that the target composite sheet for forming the protective film can be fixed to the annular frame. In addition, the adjustment is made so that the base material, the adhesive layer, and the film for forming the protective film are all concentric.

[0586] In the above manner, the Figure 2 long rectangular composite sheet for forming a protective film shown is manufactured, which is composed of a base material, an adhesive layer, a film for forming a protective film, and a release film laminated in this order along their thickness directions, and has a length of 50 m and a width of 450 mm.

[0587] As Figure 4 shown, in the obtained composite sheet for forming a protective film, 110 circular laminates (first laminate sheets) of the support sheet and the film for forming the protective film are arranged along the long side direction of the release film. The distance between adjacent first laminate sheets is 3 cm.

[0588] <Manufacture of Roll of Composite Sheet for Forming Protective Film>

[0589] The composite sheet for forming a protective film is wound in a roll shape along its long side direction around a core having a diameter of 3 inches so that the exposed surface of the release film in the obtained composite sheet for forming a protective film is the outermost surface in the radial direction of the roll, thereby obtaining a roll of composite sheet for forming a protective film with the release film on the outside and an outer diameter of 10.8 cm.

[0590] <Evaluation of Roll of Composite Sheet for Forming Protective Film>

[0591] <Measurement of Static Voltage of Release Film>

[0592] In an air atmosphere, the temperature is set to 23 °C, and the obtained roll of composite sheet for forming a protective film is stored statically for 7 days.

[0593] Next, unwind the composite sheet for forming a protective film from the roll of the composite sheet for forming a protective film, and immediately (within 5 seconds), measure the static voltage of the exposed surface of the release film on the side opposite to the side of the film for forming a protective film using an electrostatic field tester ("PFK-100" manufactured by PROSTAT CORPORATION). The results are shown in Table 1.

[0594] <Confirmation of Whether Foreign Matter is Attached to the Support Sheet>

[0595] Attach a back grinding tape ("Adwill E-3100TN" manufactured by Lintec Corporation) to one surface of a silicon mirror wafer (thickness 750 μm) with a size of 12 inches.

[0596] Next, use a laser irradiation device ("DFL73161" manufactured by DISCO Corporation) to set a focal point inside the silicon mirror wafer and irradiate the laser in such a way as to focus on the focal point, thereby forming a modified layer inside the silicon mirror wafer. At this time, set the focal point so that a plurality of silicon chips with a size of 3 mm × 3 mm can be obtained from the silicon mirror wafer. In addition, the laser is irradiated from the outside of the silicon mirror wafer on the side opposite to the side of the back grinding tape to the inside of the silicon mirror wafer.

[0597] Next, grind the exposed surface of the silicon mirror wafer (in other words, the surface on the side opposite to the side of the back grinding tape) using a grinding machine so that the thickness of the silicon mirror wafer becomes 300 μm, and at the same time, use the force applied to the silicon mirror wafer during grinding at this time to divide the silicon mirror wafer at the formation site of the modified layer to fabricate a plurality of silicon chips. Thus, a silicon chip group in a state where a plurality of silicon chips are neatly arranged and fixed on the back grinding tape is obtained.

[0598] Remove the release film from the composite sheet for forming a protective film after measuring the static voltage of the release film. Then, attach the exposed surface of the film for forming a protective film in one of the resulting first laminated sheets to the grinding surfaces (in other words, the surfaces on the side opposite to the side of the back grinding tape) of all the silicon chips in the above silicon chip group. Further, attach the region near the peripheral portion of the exposed surface of the adhesive layer in the support sheet to the annular frame, thereby fixing the composite sheet for forming a protective film to the annular frame. In this way, 20 groups of silicon chip groups with a composite sheet for forming a protective film attached to each silicon chip group and with a back grinding tape and a composite sheet for forming a protective film are fabricated in a state fixed to the annular frame.

[0599] Visually confirm whether foreign matter is attached to the exposed surface of the support sheet (in other words, the surface on the side opposite to the side of the film for forming a protective film, or the surface of the substrate on the side opposite to the adhesive layer side) in the 20 sets of silicon chip sets with composite sheets for forming a protective film, and confirm the number of silicon chip sets with composite sheets for forming a protective film to which foreign matter is attached. The results are shown in Table 1.

[0600] <Confirmation of the presence or absence of chip scattering during cold expansion of the composite sheet for forming a protective film>

[0601] After confirming whether the above-mentioned foreign matter is attached to the support sheet, remove the back grinding tape from one set of silicon chip sets with composite sheets for forming a protective film.

[0602] Next, set the silicon chip set with the composite sheet for forming a protective film on the expansion stage. At this time, make the exposed surface of the support sheet in the chip set contact the surface of the expansion stage.

[0603] Next, while cooling the entire silicon chip set with the composite sheet for forming a protective film, stretch the composite sheet for forming a protective film in a direction parallel to its surface (perform cold expansion), thereby cutting the film for forming a protective film in the composite sheet for forming a protective film at a position along the outer periphery of the silicon chip.

[0604] In the above manner, a silicon chip set with a film for forming a protective film is obtained in a state where a plurality of silicon chips with a film for forming a protective film are neatly arranged and fixed on the support sheet. Here, the silicon chip set with a film for forming a protective film refers to a silicon chip set composed of a silicon chip with a size of 3 mm × 3 mm and a film for forming a protective film of the same size provided on one of its surfaces.

[0605] The above steps were performed on all 20 sets of silicon chip sets with composite sheets for forming a protective film after confirming whether foreign matter was attached to the support sheet. Then, confirm the scattering of the silicon chips with the film for forming a protective film, that is, the number of silicon chip sets with composite sheets for forming a protective film in which chip scattering occurred. The results are shown in Table 1.

[0606] [Example 2]

[0607] <Manufacture of a roll of composite sheet for forming a protective film>

[0608] <Manufacture of the support sheet>

[0609] Manufacture a support sheet with a release film in the same manner as in Example 1.

[0610] <Manufacture of the film for forming a protective film>

[0611] (Preparation of the composition for forming a protective film (III-1))

[0612] The thermosetting protective film-forming composition (III-1)-1 was produced in the same manner as in Example 1.

[0613] <Manufacture of the film for forming the protective film>

[0614] Using a long stripping film (Lintec Corporation's "SP-PET381031", thickness 38 μm) whose one side of the film made of polyethylene terephthalate was subjected to stripping treatment by silicone treatment, the above-obtained protective film-forming composition (III-1)-1 was coated on the stripped surface of the long stripping film and dried at 100°C for 2 minutes, thereby forming a long thermosetting protective film-forming film with a thickness of 25 μm.

[0615] Furthermore, the above-obtained long protective film-forming film was punched in such a way that a plurality of circles with a diameter of 330 mm were arranged in a row along the long side direction of the stripping film.

[0616] In the above-described manner, a long laminated film composed of a long stripping film and circular protective film-forming films was obtained, and the circular protective film-forming films were arranged in a row on one surface of the stripping film.

[0617] In addition, a long double-sided adhesive tape with stripping films on both sides (Lintec Corporation's "Adwill G-01DF") was used, and the stripping film on one surface was removed. Then, for the exposed double-sided adhesive tape, punching processing was performed to remove a row of circles with a diameter of 345 mm along its long side direction, thereby obtaining a processed long double-sided adhesive tape with a stripping film.

[0618] Next, the surface on the double-sided adhesive tape side of the processed double-sided adhesive tape was bonded to the surface on the protective film-forming film side of the above-obtained laminated film. At this time, the circular protective film-forming film was arranged in the area where the circle was removed from the processed double-sided adhesive tape in such a way that the processed double-sided adhesive tape and the protective film-forming film were concentric. Thereby, a jig adhesive layer was arranged along the outer peripheral portion of the protective film-forming film.

[0619] <Manufacture of the protective film-forming composite sheet>

[0620] Next, one stripping film was removed from the structure obtained by this bonding, and the protective film-forming film and the jig adhesive layer were exposed.

[0621] In addition, the stripping film was removed from the support sheet obtained above, and the adhesive layer was exposed.

[0622] Then, the exposed surfaces of the protective film-forming film and the jig adhesive layer were bonded to the exposed surface of the adhesive layer.

[0623] Next, in order to form a circular region of the support sheet that includes the region where the film for forming the protective film is laminated, a part of the support sheet is removed, and stamping is further performed to continuously remove a part of the adhesive layer for the jig (forming the cutout). At this time, the diameter of the circular support sheet is set to 370 mm, and adjustment is made so that the base material, the adhesive layer, the film for forming the protective film, and the adhesive layer for the jig are all concentric.

[0624] In the above manner, a long rectangular composite sheet for forming a protective film is manufactured, which is formed by laminating a base material, an adhesive layer, a film for forming a protective film, and a release film in sequence along their thickness directions, and further laminating an adhesive layer for a jig between the peripheral portion of the adhesive layer and the release film. Its length is 50 m and its width is 450 mm. This composite sheet for forming a protective film is equivalent to Figure 2 In the composite sheet for forming a protective film 102 shown, a composite sheet having an adhesive layer for a jig in the region of the surface 12a of the adhesive layer 12 where the film for forming the protective film 23 is not laminated.

[0625] In the obtained composite sheet for forming a protective film, 110 circular laminates (first laminates) of the support sheet and the film for forming the protective film are arranged along the long side direction of the release film. The distance between adjacent first laminates is 3 cm.

[0626] <Manufacture of the composite sheet roll for forming a protective film>

[0627] Using the above-obtained composite sheet for forming a protective film, a composite sheet roll for forming a protective film is obtained by the same method as in the case of Example 1.

[0628] <Evaluation of the composite sheet roll for forming a protective film>

[0629] <Measurement of the static voltage of the release film>

[0630] For the above-obtained composite sheet roll for forming a protective film, in the same manner as in the case of Example 1, the static voltage of the exposed surface of the first release film on the side opposite to the film for forming the protective film immediately after unwinding is measured. The results are shown in Table 1.

[0631] <Confirmation of whether foreign matter adheres to the support sheet>

[0632] In the same manner as in the case of Example 1, visually confirm whether foreign matter adheres to the exposed surface of the support sheet in 20 sets of silicon chip groups of the composite sheet for forming a protective film, and confirm the number of silicon chip groups of the composite sheet for forming a protective film to which foreign matter adheres. The results are shown in Table 1. Here, at this time, the silicon chip group of the composite sheet for forming a protective film is fixed by attaching the exposed surface of the jig adhesive layer rather than the exposed surface of the adhesive layer in the silicon chip group of the composite sheet for forming a protective film to the annular frame.

[0633] <Confirmation of the presence or absence of chip scattering during cold expansion of the composite sheet for forming a protective film>

[0634] In the same manner as in the case of Example 1, for 20 sets of silicon chip groups of the composite sheet for forming a protective film, confirm the number of silicon chip groups in which chip scattering has occurred. The results are shown in Table 1.

[0635] [Example 3]

[0636] <Manufacture of the composite sheet roll for forming a protective film>

[0637] <Manufacture of the support sheet>

[0638] (Preparation of the adhesive composition (I-2))

[0639] Prepare an energy ray-curable adhesive composition (I-2)-1, which contains an adhesive resin (I-2a)-1 (100 parts by mass), a hexamethylene diisocyanate-based crosslinking agent ("CORONATE HL" manufactured by TOSOH CORPORATION) (6 parts by mass), and a photopolymerization initiator ("Irgacure 184", 1-hydroxycyclohexyl phenyl ketone manufactured by BASF Corporation) (3 parts by mass), and further contains methyl ethyl ketone as a solvent, wherein the total concentration of all components other than the solvent is 25% by mass. In addition, the content of the components other than methyl ethyl ketone shown here is all the content of the target excluding the solvent. Further, the adhesive resin (I-2a)-1 is a copolymer of 2EHA (80 parts by mass) and HEA (20 parts by mass), and is a resin obtained by subjecting MOI (the amount such that the total molar number of isocyanate groups in MOI is 0.8 times the total molar number of hydroxyl groups derived from HEA in the acrylic polymer) to an addition reaction with an acrylic polymer having a weight average molecular weight of 600,000.

[0640] (Manufacture of the support sheet)

[0641] Use the obtained pressure-sensitive adhesive composition (I-2)-1 to replace the pressure-sensitive adhesive composition (I-4)-1, and form an energy-ray curable pressure-sensitive adhesive layer with a thickness of 5 μm instead of a non-energy-ray curable pressure-sensitive adhesive layer with a thickness of 5 μm. Except for these points, manufacture a support sheet with a release film in the same manner as in Example 1.

[0642] <Manufacture of Film for Forming Protective Film>

[0643] Form the film for forming the protective film in the same manner as in Example 2 to manufacture the laminated film.

[0644] <Manufacture of Composite Sheet for Forming Protective Film and Roll of Composite Sheet for Forming Protective Film>

[0645] Except for using the obtained support sheet, manufacture the composite sheet for forming the protective film and the roll of the composite sheet for forming the protective film in the same manner as in Example 2.

[0646] "Evaluation of Roll of Composite Sheet for Forming Protective Film"

[0647] For the obtained roll of composite sheet for forming the protective film, evaluate three items in the same manner as in Example 2. The results are shown in Table 1.

[0648] [Example 4]

[0649] <Manufacture of Roll of Composite Sheet for Forming Protective Film>

[0650] Use a long antistatic-treated polypropylene (PP) film (thickness 80 μm, colorless) to replace the above-mentioned long polypropylene (PP) film (thickness 80 μm, colorless) as the base material. Except for this point, manufacture the roll of composite sheet for forming the protective film in the same manner as in Example 1.

[0651] Use a surface resistivity tester ("R12704 Resistivitychamber" manufactured by ADVANTEST CORPORATION), set the applied voltage to 100 V, and measure the surface resistivity of the polypropylene film. The result is 8.6×10 9 Ω / m 2 .

[0652] <Evaluation of Roll of Composite Sheet for Forming Protective Film>

[0653] For the obtained roll of composite sheet for forming the protective film, evaluate three items in the same manner as in Example 1. The results are shown in Table 1.

[0654] [Comparative Example 1]

[0655] "Manufacture of Composite Sheet Roll for Forming Protective Film"

[0656] "<Manufacture of Composite Sheet for Forming Protective Film>"

[0657] The composite sheet for forming a protective film was manufactured in the same manner as in Example 1.

[0658] "<Manufacture of Composite Sheet Roll for Forming Protective Film>"

[0659] The composite sheet for forming a protective film was wound around a core with a diameter of 3 inches in a roll shape along its long side direction in such a way that the exposed surface of the base material, rather than the exposed surface of the release film in the obtained composite sheet for forming a protective film, was the outermost surface in the radial direction of the roll. As a result, the release film was wound inside (in other words, the base material was wound outside). Except for this point, the composite sheet roll for forming a protective film was manufactured in the same manner as in Example 1.

[0660] "Evaluation of Composite Sheet Roll for Forming Protective Film"

[0661] For the obtained composite sheet roll for forming a protective film, three items were evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0662] [Table 1]

[0663]

[0664] From the above results, it can be seen that in Examples 1 to 4, no foreign matter was observed to adhere to the support sheet in all the silicon chip sets with the composite sheet for forming a protective film, and in addition, no chip scattering was observed even during cold expansion.

[0665] In the composite sheet rolls for forming a protective film in Examples 1 to 4, the release film was wound outside.

[0666] In the composite sheet rolls for forming a protective film in Examples 1 to 4, the static voltage of the release film was 0.2 to 1.5 kV.

[0667] In contrast, in Comparative Example 1, foreign matter was observed to adhere to the support sheet in the silicon chip set with the composite sheet for forming a protective film, and in addition, chip scattering was observed during cold expansion. In the composite sheet roll for forming a protective film in Comparative Example 1, the release film was wound inside.

[0668] Industrial Applicability

[0669] The present invention can be used in the manufacture of semiconductor devices.

Claims

1. A composite sheet roll for forming a protective film, which is a composite sheet roll for forming a protective film formed by winding a composite sheet for forming a protective film into a roll shape, wherein the composite sheet for forming a protective film includes a support sheet, a protective film forming film provided on one surface of the support sheet, and a release film provided on the surface of the protective film forming film opposite to the support sheet side, the composite sheet for forming a protective film is wound into a roll shape such that the outermost surface on the radial direction of the roll is the outermost surface on the release film side of the composite sheet for forming a protective film, when the static voltage of the outermost surface on the release film side of the composite sheet for forming a protective film is measured immediately after unwinding the composite sheet for forming a protective film from the composite sheet roll for forming a protective film, the static voltage is 3.0 kV or less.

2. The composite sheet roll for forming a protective film according to claim 1, wherein, The protective film forming film is thermosetting or energy ray curable.

3. The composite sheet roll for forming a protective film according to claim 1 or 2, wherein the support sheet includes a base material and an adhesive layer provided on one surface of the base material, the adhesive layer is disposed between the base material and the protective film forming film.

4. The composite sheet roll for forming a protective film according to claim 3, wherein, The adhesive layer is energy ray curable.

Images