CN108728000B

CN108728000B - Dicing die bonding film

Info

Publication number: CN108728000B
Application number: CN201810345577.4A
Authority: CN
Inventors: 木村雄大; 高本尚英; 大西谦司; 宍户雄一郎; 福井章洋; 大和道子; 井上真一
Original assignee: Nitto Denko Corp
Current assignee: Nitto Denko Corp
Priority date: 2017-04-17
Filing date: 2018-04-17
Publication date: 2022-07-08
Anticipated expiration: 2038-04-17
Also published as: KR20180116750A; KR102528254B1; JP2022051806A; CN108728000A

Abstract

The invention provides a dicing die-bonding film suitable for achieving good pick-up of a semiconductor chip with an adhesive layer from a dicing tape. A dicing die-bonding film (X) of the present invention is provided with a dicing tape (10) and an adhesive layer (20). The dicing tape (10) has a laminated structure including a base material (11) and an adhesive layer (12). The adhesive layer (20) is releasably adhered to the adhesive layer (12). The surface (12a) of the adhesive layer (12) and the surface (20b) of the adhesive layer (20) for forming the interface between the adhesive layer (12) and the adhesive layer (20) can generate 3.5mJ/m²The above surface free energy difference.

Description

Dicing die bonding film

Technical Field

The present invention relates to a dicing die-bonding film that can be used in a manufacturing process of a semiconductor device.

Background

In the manufacturing process of a semiconductor device, a dicing die-bonding film is sometimes used in order to obtain a semiconductor chip with an adhesive film having a die-bonding size equivalent to that of the semiconductor chip, that is, a semiconductor chip with an adhesive layer for die-bonding. The dicing die-bonding film has a size corresponding to a semiconductor wafer to be processed, and includes, for example: a dicing tape comprising a substrate and an adhesive layer; and a die bond film (adhesive layer) releasably adhering to the adhesive layer side.

As one of the methods for obtaining a semiconductor chip with an adhesive layer by using a dicing die-bonding film, a method is known in which a dicing tape in the dicing die-bonding film is spread to cut the die-bonding film. In this method, first, a semiconductor wafer is bonded to a die bond film obtained by dicing the die bond film. The semiconductor wafer is processed so that it can be cut into a plurality of semiconductor chips together with the cutting of the die bonding film, for example. Next, in order to cut the die-bonding film on the dicing tape so as to generate a plurality of small adhesive film pieces (adhesive layers) that are respectively adhered to the semiconductor chips from the die-bonding film, the dicing tape that has been cut into the die-bonding film is spread by a spreading device (spreading step for cutting). In this expanding step, the semiconductor wafer on the die bond film is also cut at a position corresponding to a cut position in the die bond film, and the semiconductor wafer is singulated into a plurality of semiconductor chips on the dicing die bond film and/or the dicing tape. Next, a second spreading step (spreading step for separation) is performed on the plurality of semiconductor chips with the adhesive layer after the dicing tape is cut so as to spread the distance between the semiconductor chips. Next, after the cleaning step, for example, the semiconductor chips with the adhesive layer on the dicing tape are lifted up from the lower side of the dicing tape by the needle members of the pickup mechanism, and then the semiconductor chips are picked up from the dicing tape (pickup step). In this case, the adhesive layer in the semiconductor chip with the adhesive layer of the pickup object needs to be appropriately peeled from the adhesive layer of the dicing tape. In this manner, a semiconductor chip with an adhesive layer as a die bond film was obtained. The semiconductor chip with the adhesive layer is fixed to an adherend such as a mounting board by die bonding via the adhesive layer. For example, the related art of dicing a die-bonding film used as described above is described in, for example, patent documents 1 to 3 below.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2007-2173

Patent document 2: japanese patent application laid-open No. 2010-177401

Patent document 3: japanese patent laid-open No. 2012-23161

Disclosure of Invention

Problems to be solved by the invention

Fig. 14 is a schematic cross-sectional view of a dicing die-bonding film Y as an example of the dicing die-bonding film. The dicing die-bonding film Y includes a dicing tape 60 and a die-bonding film 70. The dicing tape 60 has a laminated structure of a base material 61 and an adhesive layer 62 exerting adhesive force. The die-bonding film 70 adheres to the adhesive layer 62 by virtue of the adhesive force of the adhesive layer 62. Such a dicing die-bonding film Y has a disk shape having a size corresponding to a semiconductor wafer as a workpiece to be processed in a manufacturing process of a semiconductor device, and can be used in the extension step. For example, as shown in fig. 15, the expanding step is performed in a state where the semiconductor wafer 81 is bonded to the die bonding film 70 and the ring frame 82 is attached to the adhesive layer 62. The ring frame 82 is a frame member that mechanically abuts against a conveying mechanism such as a conveying arm provided in the expanding device when the ring frame is attached to the dicing die bonding film Y and the workpiece is conveyed. The dicing die-bonding film Y is designed in such a manner that the ring frame 82 can be fixed to the film by the adhesive force of the adhesive layer 62 of the dicing tape 60. That is, the dicing die-bonding film Y has a conventional design in which a loop-shaped frame member-attaching region is secured around the die-bonding film 70 in the adhesive layer 62 of the dicing tape 60. In such a design, the distance between the outer peripheral end 62e of the adhesive layer 62 and the outer peripheral end 70e of the die bond film 70 in the film in-plane direction is about 10 to 30 mm.

However, in the dicing die-bonding film including the dicing tape and the die-bonding film on the pressure-sensitive adhesive layer thereof, when the dicing tape and/or the pressure-sensitive adhesive layer thereof and the die-bonding film have the same design dimensions in the in-plane direction of the film, the die-bonding film needs to have a function of holding the loop frame, and therefore, it is necessary to secure adhesion to the loop frame. In order to secure the adhesion of the die-bonding film to the ring frame, the die-bonding film is, for example, less elastic than the die-bonding film 70 in the dicing die-bonding film Y. However, this low elasticity tends to increase the peeling force required for peeling the die-bonding film from the adhesive layer of the dicing tape. In order to achieve satisfactory pickup of the semiconductor chip with the adhesive layer in the pickup step, it is preferable that the peel force between the adhesive layer of the dicing tape and the die bond film is small.

As described above, in dicing the die-bonding film, there are some cases where there are technical difficulties involved in achieving good pickup of the semiconductor chip with the adhesive layer from the dicing tape. The present invention has been made in view of the above circumstances, and an object thereof is to provide a dicing die-bonding film suitable for achieving satisfactory pickup of a semiconductor chip with an adhesive layer from a dicing tape.

Means for solving the problems

The dicing die-bonding film provided by the invention comprises a dicing tape and an adhesive layer. The dicing tape has a laminated structure including a substrate and an adhesive layer. The adhesive layer is releasably adhered to the adhesive layer in the dicing tape. For forming adhesive layer of dicing tapeThe surface of the adhesive layer and the surface of the adhesive layer at the interface with the adhesive layer thereon can generate 3.5mJ/m²The above surface free energy difference. That is, the dicing die-bonding film includes: in the adhesive layer surface and the adhesive layer surface forming the interface between the adhesive layer and the adhesive layer, the difference between the surface free energy (1 st surface free energy) of the adhesive layer surface and the surface free energy (2 nd surface free energy) of the adhesive layer surface was 3.5mJ/m²Or the difference between the two can be 3.5mJ/m²The above. For example, when the pressure-sensitive adhesive layer of the dicing tape is a curable pressure-sensitive adhesive layer such as a radiation curable pressure-sensitive adhesive layer, the difference between the 1 st surface free energy in the pressure-sensitive adhesive layer and the 2 nd surface free energy in the cured pressure-sensitive adhesive layer is 3.5mJ/m²The dicing die-bonding film is configured in the above manner. In the present invention, the surface free energy difference is preferably 4mJ/m²More preferably 5mJ/m or more²The above. The dicing die-bonding film configured as described above can be used to obtain a semiconductor chip with an adhesive layer in the manufacturing process of a semiconductor device.

In the manufacturing process of a semiconductor device, as described above, in order to obtain a semiconductor chip with an adhesive layer, a spreading step and a pickup step of bonding a film by dicing a die may be performed. In the pickup step, it is necessary to be able to pick up the semiconductor chip from the dicing tape by peeling the adhesive layer of the semiconductor chip with the adhesive layer from the adhesive layer of the dicing tape. The present inventors have found that: the difference between the free energies of the 1 st and 2 nd surfaces at the interface between the adhesive layer of the dicing die-bonding film and the adhesive layer of the dicing tape is 3.5mJ/m²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above state is suitable for achieving good pickup in the pickup process. Specifically, the examples and comparative examples are described below. At the interface between the adhesive layer and the pressure-sensitive adhesive layer, the greater the difference between the surface free energy of the surface of the adhesive layer and the surface free energy of the surface of the pressure-sensitive adhesive layer, the less likely the constituent materials between the two layers will migrate. Moreover, the material constituting the adhesive layer and the pressure-sensitive adhesive layer is not easily transferred and is suitable for being secured between the two layersThe low peel force is suitable for ensuring the adhesive strength of the adhesive layer to the frame member by the low elasticity and suppressing the increase of the peel force between the adhesive layer and the pressure-sensitive adhesive layer when the low elasticity of the adhesive layer is required. The difference between the 1 st and 2 nd surface free energies at the interface between the adhesive layer and the pressure-sensitive adhesive layer was 3.5mJ/m²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above configuration is suitable for ensuring a small peeling force between the pressure-sensitive adhesive layer and the adhesive layer to such an extent that good pick-up of the semiconductor chip with the adhesive layer can be achieved in the pick-up step.

The dicing die-bonding film of the present invention, which is suitable for securing the adhesive strength of the adhesive layer to the frame member by reducing the elasticity of the adhesive layer and suppressing the increase in the peeling force between the adhesive layer and the dicing tape adhesive layer, is suitable for designing the dicing tape and/or the adhesive layer on the dicing tape and the adhesive layer in the film in the in-plane direction of the film so that the adhesive layer includes the work bonding region and the frame member bonding region. In the dicing die-bonding film, for example, the following design can be adopted: the outer peripheral end of the adhesive layer is located within 1000 μm from the outer peripheral ends of the base material of the dicing tape and the adhesive layer in the film in-plane direction. The dicing die-bonding film having such a configuration is suitable for performing processing for forming one dicing tape having a laminated structure of a base material and an adhesive layer and processing for forming one adhesive layer at a time by processing such as primary punching processing.

In the manufacturing process of the dicing die-bonding film Y, a processing step (1 st processing step) for forming the dicing tape 60 having a predetermined size and shape and a processing step (2 nd processing step) for forming the die-bonding film 70 having a predetermined size and shape are required as separate steps. In the first processing step 1, for example, a laminated sheet having a laminated structure of a predetermined separator, a base material layer to be formed as the base material 61, and a pressure-sensitive adhesive layer to be formed as the pressure-sensitive adhesive layer 62 interposed therebetween is subjected to processing in which a processing blade is advanced from the base material layer side to reach the separator. The adhesive layer that will be formed as the adhesive layer 62 is formed by applying an adhesive composition to the separator and then drying. Through the first process step 1, a dicing tape 60 having a laminated structure of an adhesive layer 62 and a substrate 61 on a separator is formed on the separator. In the 2 nd processing step, for example, a processing is performed on a laminated sheet body having a laminated structure of a predetermined separator and an adhesive layer to be formed into the die bond film 70, by a processing blade entering from the adhesive layer side until reaching the separator. The adhesive layer to be formed into the die-bonding film 70 is formed by applying an adhesive composition to the separator and then drying it. Through the 2 nd processing step, a die bond film 70 is formed on the spacer. The dicing tape 60 and the die bond film 70 formed in the independent steps are aligned and bonded. Fig. 16 shows a cut die-bonding film Y having a spacer 83 covering the surface of the die-bonding film 70 and the surface of the adhesive layer 62.

On the other hand, the dicing die-bonding film of the present invention in which the dicing tape and/or the adhesive layer thereof and the adhesive layer thereon as the die-bonding film have substantially the same design dimensions in the in-film direction can be manufactured, for example, as follows. First, an adhesive composition layer is formed by applying an adhesive layer-forming composition to a predetermined separator. Then, on the adhesive composition layer, an adhesive composition layer was formed by coating a composition for forming a dicing tape adhesive layer. Next, an adhesive layer and an adhesive layer are formed on the separator by one-time drying of these composition layers. Then, a base material for dicing tape is bonded to the exposed surface of the adhesive layer. Next, the laminated sheet body having a laminated structure of the separator, the adhesive layer, and the base material is processed by entering a processing blade from the base material side until the processing blade reaches the separator. Thus, a dicing die-bonding film having a predetermined size and shape and having a laminated structure of an adhesive layer, an adhesive layer and a base material on a separator is formed on the separator. The dicing die-bonding film of the present invention in which the dicing tape and/or the adhesive layer thereof and the adhesive layer thereon have substantially the same design dimensions in the film in-plane direction is suitable for use in one-time punching process or the likeThe processing is performed at once for processing one dicing tape for forming a laminated structure having a base material and an adhesive layer, and for processing for forming one adhesive layer. The dicing die-bonding film is suitable for efficient production from the viewpoints of reducing the number of production steps, reducing the production cost, and the like. In addition, the above-mentioned production method by lamination formation of the composition for forming an adhesive layer and the composition for forming a dicing tape adhesive layer and one-time drying of the two composition layers tends to increase the peeling force between the two layers at the interface between the dicing tape adhesive layer and the adhesive layer, as compared with the production method in which the dicing tape adhesive layer and the adhesive layer are formed separately and then bonded to each other, but the difference between the 1 st and 2 nd surface free energies at the interface between the adhesive layer and the dicing tape adhesive layer is 3.5mJ/m as described above²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above-described configuration of the present invention is suitable for ensuring a small peeling force between the pressure-sensitive adhesive layer and the adhesive layer to such an extent that good pick-up of the semiconductor chip with the adhesive layer can be achieved in the pick-up step.

As described above, the dicing die-bonding film of the present invention is suitable for achieving good pick-up of the semiconductor chip with the adhesive layer from the dicing tape.

From the viewpoint of ensuring the above-described small peeling force between the dicing tape pressure-sensitive adhesive layer and the adhesive layer of the dicing die-bonding film of the present invention, the dicing tape pressure-sensitive adhesive layer is configured as follows: preferably, the thickness of the adhesive layer is 32mJ/m on the surface forming the adhesion interface with the adhesive layer²Less, more preferably 30mJ/m²Hereinafter, more preferably 28mJ/m²The following surface free energy (No. 2 surface free energy). When the dicing tape pressure-sensitive adhesive layer is a curable pressure-sensitive adhesive layer such as a radiation curable pressure-sensitive adhesive layer, the 2 nd surface free energy of the cured pressure-sensitive adhesive layer is preferably 32mJ/m²Below, more preferably 30mJ/m²Hereinafter, more preferably 28mJ/m²The following. In addition, from the viewpoint of ensuring a proper adhesive force between the dicing tape pressure-sensitive adhesive layer and the adhesive layer so that peeling does not occur between the two layers during the transportation of the dicing die-bonding film of the present inventionThe dicing tape adhesive layer is constituted as follows: preferably 15mJ/m on the surface forming the adhesion interface with the adhesive layer²More preferably 18mJ/m or more²Above, more preferably 20mJ/m²The above surface free energy (2 nd surface free energy). When the dicing tape pressure-sensitive adhesive layer is a curable pressure-sensitive adhesive layer such as a radiation curable pressure-sensitive adhesive layer, the 2 nd surface free energy of the cured pressure-sensitive adhesive layer is preferably 15mJ/m²More preferably 18mJ/m or more²More preferably 20mJ/m or more²The above.

The above-mentioned 1 st surface free energy of the adhesive layer of the dicing die-bonding film of the present invention is preferably 30mJ/m from the viewpoint of securing the required adhesive force between the adhesive layer and the dicing tape adhesive layer in the dicing die-bonding film²Above, more preferably 31mJ/m²More preferably 32mJ/m²The above. From the viewpoint of ensuring the above-mentioned small peel force between the adhesive layer and the pressure-sensitive adhesive layer, the 1 st surface free energy is preferably 45mJ/m²Hereinafter, more preferably 43mJ/m²The concentration is preferably 40mJ/m or less²The following.

The adhesive layer of the dicing die-bonding film exhibits a 180 DEG peel adhesion to the SUS plane preferably at least 0.1N/10mm, more preferably at least 0.3N/10mm, and even more preferably at least 0.5N/10mm in a peel test under conditions of 23 ℃, a peel angle of 180 DEG, and a stretching speed of 10 mm/min. This configuration of the adhesive force of the adhesive layer is suitable for securing the holding of the frame member by the dicing die-bonding film. Further, the adhesive layer exhibits a 180 DEG peel adhesion to the SUS plane preferably of 20N/10mm or less, more preferably of 10N/10mm or less, in a peel test under the same conditions. This constitution concerning the adhesive force of the adhesive layer is preferable in terms of securing the removability of the frame member from the dicing die-bonding film.

The adhesive layer of the dicing die-bonding film preferably has a tensile storage modulus at 23 ℃ of 100MPa or more, more preferably 500MPa or more, and even more preferably 1000MPa or more, as measured under conditions of an initial inter-jig distance of 10mm, a frequency of 10Hz, a dynamic strain. + -. 0.5 μm, and a temperature rise rate of 5 ℃/min with respect to an adhesive layer sample sheet having a width of 4mm and a thickness of 80 μm. This configuration of the tensile storage modulus of the adhesive layer is suitable for securing the adhesive force of the adhesive layer to the frame member, and therefore is suitable for securing the holding of the frame member by the dicing die-bonding film of the present invention. The tensile storage modulus at 23 ℃ of the adhesive layer measured under the same conditions is preferably 4000MPa or less, more preferably 3000MPa or less, and still more preferably 2000MPa or less. This configuration of the tensile storage modulus of the adhesive layer is preferable in terms of ensuring the detachability of the frame member from the dicing die-bonding film.

In the dicing die-bonding film, the dicing tape pressure-sensitive adhesive layer is preferably a radiation-curable pressure-sensitive adhesive layer, and the peel force between the pressure-sensitive adhesive layer and the adhesive layer after radiation curing in a T-peel test at 23 ℃ and a peel speed of 300 mm/min is preferably 0.06N/20mm or more, more preferably 0.1N/20mm or more, and still more preferably 0.15N/20mm or more. Such a configuration is suitable for ensuring the adhesion between the adhesive layer and the adhesive layer on the adhesive layer after curing of the dicing tape, and therefore, when the dicing die-bonding film is used to perform the expanding step after curing of the adhesive layer of the dicing tape, it is preferable to suppress the occurrence of partial peeling, i.e., floating, of the semiconductor chip with the adhesive layer from the adhesive layer in the expanding step. Further, the peel force between the pressure-sensitive adhesive layer and the adhesive layer after radiation curing in a T-peel test at 23 ℃ and a peel speed of 300 mm/min is preferably 0.25N/20mm or less, more preferably 0.23N/20mm or less, and still more preferably 0.2N/20mm or less. Such a configuration is suitable for achieving good pickup of the semiconductor chip with the adhesive layer from the adhesive layer after curing in the pickup step performed after curing of the dicing tape adhesive layer.

In the dicing die-bonding film, the dicing tape pressure-sensitive adhesive layer is preferably a radiation-curable pressure-sensitive adhesive layer, and the peeling force between the pressure-sensitive adhesive layer and the adhesive layer before radiation curing in a T-peel test at 23 ℃ and a peeling speed of 300 mm/min is preferably 2N/20mm or more. Such a configuration is suitable for securing adhesion between the uncured adhesive layer of the dicing tape and the adhesive layer thereon, and therefore, when the dicing die-bonding film is used to perform the expanding step in a state where the adhesive layer of the dicing tape is uncured, it is suitable for suppressing generation of partial peeling, that is, lifting, of the semiconductor chip with the adhesive layer from the adhesive layer in the expanding step.

The difference in arithmetic average surface roughness (Ra) between the surface of the pressure-sensitive adhesive layer and the surface of the adhesive layer, which is used to form the interface between the pressure-sensitive adhesive layer and the adhesive layer of the dicing tape in the dicing die-bonding film, is preferably 100nm or less. Such a configuration is suitable for securing adhesion between the dicing tape adhesive layer and the adhesive layer thereon, and therefore, it is suitable for suppressing generation of partial peeling, that is, floating, of the semiconductor chip with the adhesive layer from the adhesive layer in the spreading step.

The pressure-sensitive adhesive layer in the dicing die-bonding film preferably contains an acrylic polymer containing: a 1 st unit derived from an alkyl (meth) acrylate having an alkyl group with 10 or more carbon atoms, and a2 nd unit derived from 2-hydroxyethyl (meth) acrylate. "(meth) acrylate" means "acrylate" and/or "methacrylate". The acrylic polymer in the pressure-sensitive adhesive layer contains units derived from an alkyl (meth) acrylate having an alkyl group with 10 or more carbon atoms and units derived from 2-hydroxyethyl (meth) acrylate, and is suitable for achieving high shear adhesion between the pressure-sensitive adhesive layer of the dicing tape and the pressure-sensitive adhesive layer thereon, and therefore, is suitable for appropriately applying a cleaving force to the pressure-sensitive adhesive layer on the dicing tape stretched in the in-plane direction in the stretching step to cleave the pressure-sensitive adhesive layer.

The acrylic polymer in the pressure-sensitive adhesive layer of the dicing die-bonding film preferably has a molar ratio of the 1 st unit to the 2 nd unit of 1 or more, more preferably 3 or more, and still more preferably 5 or more. Such a configuration is preferable for ensuring high shear adhesion between the dicing tape pressure-sensitive adhesive layer and the adhesive layer thereon as described above and suppressing the adhesive interaction between the two layers in the stacking direction, and thus contributes to achieving good pickup in the pickup step. The molar ratio is preferably 40 or less, more preferably 35 or less, and still more preferably 30 or less. Such a configuration is preferable in that adhesion between the dicing tape adhesive layer and the adhesive layer is secured, and generation of partial peeling, that is, floating, of the semiconductor chip with the adhesive layer from the adhesive layer is suppressed in the spreading step.

The acrylic polymer in the pressure-sensitive adhesive layer of the dicing die-bonding film is preferably an addition product of an unsaturated functional group-containing isocyanate compound as a radiation polymerizable component. In this case, the molar ratio of the unsaturated functional group-containing isocyanate compound to the 2 nd unit derived from 2-hydroxyethyl (meth) acrylate in the acrylic polymer is preferably 0.1 or more, more preferably 0.2 or more, and still more preferably 0.3 or more. These configurations are suitable for appropriately increasing the elasticity of the pressure-sensitive adhesive layer through the reaction between the acrylic polymer and the unsaturated functional group-containing isocyanate compound, and contribute to good cleavage of the pressure-sensitive adhesive layer in the spreading step. In addition, from the viewpoint of reducing low molecular weight components in the pressure-sensitive adhesive layer after curing, in the reaction composition containing the unsaturated functional group-containing isocyanate compound and the acrylic polymer for forming an addition product obtained by adding the unsaturated functional group-containing isocyanate compound to the acrylic polymer, the molar ratio of the unsaturated functional group-containing isocyanate compound to the unit derived from 2-hydroxyethyl (meth) acrylate (unit No. 2) in the acrylic polymer is preferably 2 or less, more preferably 1.5 or less, and still more preferably 1.3 or less.

Drawings

Fig. 1 is a schematic cross-sectional view of a dicing die-bonding film according to an embodiment of the present invention.

Fig. 2 shows an example of the case where the dicing die-bonding film shown in fig. 1 is provided with a separator.

Fig. 3 shows an example of a method for manufacturing the dicing die-bonding film shown in fig. 1.

Fig. 4 shows a part of the steps in the method for manufacturing a semiconductor device using the dicing die-bonding film shown in fig. 1.

Fig. 5 shows a process subsequent to the process shown in fig. 4.

Fig. 6 shows a subsequent process to that shown in fig. 5.

Fig. 7 shows a process subsequent to the process shown in fig. 6.

Fig. 8 shows a subsequent process to the process shown in fig. 7.

Fig. 9 shows a subsequent process to the process shown in fig. 8.

Fig. 10 shows a part of the steps in a modification of the semiconductor device manufacturing method using the dicing die-bonding film shown in fig. 1.

Fig. 11 shows a part of the steps in a modification of the semiconductor device manufacturing method using the dicing die-bonding film shown in fig. 1.

Fig. 12 shows a part of the steps in a modification of the semiconductor device manufacturing method using the dicing die-bonding film shown in fig. 1.

Fig. 13 shows a part of the steps in a modification of the semiconductor device manufacturing method using the dicing die-bonding film shown in fig. 1.

Fig. 14 is a schematic cross-sectional view of a conventional dicing die-bonding film.

Fig. 15 shows a use mode of the dicing die-bonding film shown in fig. 14.

Fig. 16 shows a feeding mode of the dicing die-bonding film shown in fig. 14.

Description of the reference numerals

X-cut die-bonding film

10 cutting belt

11 base material

11e outer peripheral end

12 adhesive layer

12e outer peripheral end

20. 21 adhesive layer

20e outer peripheral end

W, 30A, 30C semiconductor wafer

30B semiconductor wafer division body

30a dividing groove

30b modified region

31 semiconductor chip

Detailed Description

Fig. 1 is a schematic cross-sectional view of a dicing die-bonding film X according to an embodiment of the present invention. The dicing die-bonding film X is used in, for example, a spreading step described later in a process of obtaining a semiconductor chip with an adhesive layer in the manufacture of a semiconductor device, and has a laminated structure including a dicing tape 10 and an adhesive layer 20. The dicing die-bonding film X has a disk shape having a size corresponding to a semiconductor wafer to be processed in a manufacturing process of a semiconductor device, and has a diameter in a range of, for example, 345 to 380mm (12-inch wafer compatible type), 245 to 280mm (8-inch wafer compatible type), 195 to 230mm (6-inch wafer compatible type), or 495 to 530mm (18-inch wafer compatible type).

In the dicing die-bonding film X, the dicing tape 10 has a laminated structure including a base material 11 and an adhesive layer 12. The pressure-sensitive adhesive layer 12 has a pressure-sensitive adhesive surface 12a on the pressure-sensitive adhesive layer 20 side. The adhesive layer 20 has

surfaces

20a and 20b, and includes a work attaching region and a frame member attaching region on the surface 20a side, and is releasably adhered to the adhesive layer 12 of the dicing tape 10 and/or the adhesive surface 12a thereof on the surface 20b side. The adhesive surface 12a of the adhesive layer 12 and the surface 20b of the adhesive layer 20 form a two-layer interface. The dicing die-bonding film X has the following structure: the difference between the surface free energy (1 st surface free energy) of the surface 20b of the adhesive layer 20 and the surface free energy (2 nd surface free energy) of the adhesive surface 12a of the adhesive layer 12 was 3.5mJ/m²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above constitution; or so that the surface free energy difference is 3.5mJ/m²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above constitution. In the present invention, the surface of the adhesive layer and the adhesive layerThe surface free energy of each surface is water (H) which is in contact with a surface to be inspected under the conditions of 20 ℃ and 65% relative humidity₂O) and diiodomethane (CH)₂I₂) The contact angles θ w and θ i of each droplet of (2) were measured with a contact angle meter, and γ s was determined by the method described in Journal of Applied Polymer Science, vol.13, p1741-1747(1969) using the contact angle values^d(Dispersion force component of surface free energy) and γ s^h(hydrogen bonding force component of surface free energy), and a value γ s (═ γ s) obtained by adding the two components^d+γs^h). The method for deriving the surface free energy γ s is specifically shown in the examples.

The base material 11 of the dicing tape 10 is a member functioning as a support in the dicing tape 10 and/or the dicing die-bonding film X. As the substrate 11, for example, a plastic substrate (particularly, a plastic film) can be suitably used. Examples of the constituent material of the plastic substrate include: polyvinyl chloride, polyvinylidene chloride, polyolefin, polyester, polyurethane, polycarbonate, polyether ether ketone, polyimide, polyetherimide, polyamide, wholly aromatic polyamide, polyphenylene sulfide, aromatic polyamide, fluororesin, cellulose-based resin, and silicone resin. Examples of the polyolefin include: low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homo-polypropylene, polybutene, polymethylpentene, ethylene-vinyl acetate copolymer (EVA), ionomer resin, ethylene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid ester copolymer, ethylene-butene copolymer, and ethylene-hexene copolymer. Examples of the polyester include: polyethylene terephthalate (PET), polyethylene naphthalate, and polybutylene terephthalate (PBT). The substrate 11 may be formed of one material, or may be formed of two or more materials. The substrate 11 may have a single-layer structure or a multi-layer structure. When the substrate 11 is formed of a plastic film, it may be an unstretched film, a uniaxially stretched film, or a biaxially stretched film. When the pressure-sensitive adhesive layer 12 on the substrate 11 is an ultraviolet-curable pressure-sensitive adhesive layer, as described later, the substrate 11 preferably has ultraviolet transparency.

When the dicing tape 10 and/or the base material 11 is shrunk by, for example, local heating during use of the dicing die-bonding film X, the base material 11 preferably has heat shrinkability. From the viewpoint of ensuring good heat shrinkability of the base material 11, the base material 11 preferably contains an ethylene-vinyl acetate copolymer as a main component. The main component of the substrate 11 is a component that accounts for the largest mass ratio among the components constituting the substrate. In the case where the base material 11 is formed of a plastic film, the base material 11 is preferably a biaxially stretched film in terms of achieving isotropic heat shrinkability with respect to the dicing tape 10 and/or the base material 11. The heat shrinkage rate in a heat treatment test performed under the conditions of a heating temperature of 100 ℃ and a heat treatment time of 60 seconds is preferably 2 to 30%, more preferably 2 to 25%, even more preferably 3 to 20%, and even more preferably 5 to 20% in the dicing tape 10 and/or the base material 11. The heat shrinkage ratio is at least one of a heat shrinkage ratio in the MD direction and a heat shrinkage ratio in the TD direction.

The surface of the substrate 11 on the side of the pressure-sensitive adhesive layer 12 may be subjected to a physical treatment, a chemical treatment, or an undercoating treatment for improving adhesion to the pressure-sensitive adhesive layer 12. Examples of the physical treatment include: corona treatment, plasma treatment, sand blast treatment, ozone exposure treatment, flame exposure treatment, high voltage shock exposure treatment, and ionizing radiation treatment. The chemical treatment may be, for example, a chromic acid treatment. This treatment for improving the adhesion is preferably performed on the entire surface of the substrate 11 on the side of the pressure-sensitive adhesive layer 12.

The thickness of the base material 11 is preferably 40 μm or more, more preferably 50 μm or more, further preferably 55 μm or more, and further preferably 60 μm or more, from the viewpoint of ensuring the strength with which the base material 11 functions as a support for the dicing tape 10 and/or the dicing die-bonding film X. From the viewpoint of achieving appropriate flexibility of the dicing tape 10 and/or the dicing die-bonding film X, the thickness of the base material 11 is preferably 200 μm or less, more preferably 180 μm or less, and still more preferably 150 μm or less.

The adhesive layer 12 of the dicing tape 10 contains an adhesive. The pressure-sensitive adhesive may be a pressure-sensitive adhesive in which the adhesive strength can be intentionally lowered by an external action such as irradiation with radiation or heating (adhesive strength-lowering pressure-sensitive adhesive), or may be a pressure-sensitive adhesive in which the adhesive strength is hardly or not lowered by an external action (adhesive strength-non-lowering pressure-sensitive adhesive). Whether an adhesive strength-reducing adhesive or a non-adhesive strength-reducing adhesive is used as the adhesive in the adhesive layer 12 can be appropriately selected according to the method of using the dicing die-bonding film X to singulate semiconductor chips that are singulated using the dicing die-bonding film X, conditions, and the like.

When an adhesive force decreasing type adhesive is used as the adhesive in the adhesive layer 12, a state in which the adhesive layer 12 exhibits a relatively high adhesive force and a state in which the adhesive force exhibits a relatively low adhesive force can be used separately in the use of the dicing die-bonding film X. For example, when the dicing die-bonding film X is used in the spreading step described later, the high adhesive force state of the adhesive layer 12 is used in order to suppress or prevent the adhesive layer 20 from floating and peeling from the adhesive layer 12, and thereafter, in the pick-up step described later for picking up the semiconductor chip with the adhesive layer from the dicing tape 10 of the dicing die-bonding film X, the low adhesive force state of the adhesive layer 12 can be used in order to easily pick up the semiconductor chip with the adhesive layer from the adhesive layer 12.

Examples of the adhesive force-reducing adhesive agent include a radiation-curable adhesive agent (an adhesive agent having radiation curability), a heat-expandable adhesive agent, and the like. In the pressure-sensitive adhesive layer 12 of the present embodiment, one kind of the pressure-sensitive adhesive having a reduced adhesive strength may be used, or two or more kinds of the pressure-sensitive adhesive having a reduced adhesive strength may be used. The entire pressure-sensitive adhesive layer 12 may be formed of a pressure-sensitive adhesive of reduced adhesive strength, or a part of the pressure-sensitive adhesive layer 12 may be formed of a pressure-sensitive adhesive of reduced adhesive strength. For example, when the pressure-sensitive adhesive layer 12 has a single-layer structure, the pressure-sensitive adhesive layer 12 may be entirely formed of a pressure-sensitive adhesive of reduced adhesive strength, a predetermined portion of the pressure-sensitive adhesive layer 12 may be formed of a pressure-sensitive adhesive of reduced adhesive strength, and the other portion may be formed of a pressure-sensitive adhesive of non-reduced adhesive strength. When the pressure-sensitive adhesive layer 12 has a laminated structure, all layers forming the laminated structure may be formed of a pressure-sensitive adhesive of reduced adhesive strength, or some layers in the laminated structure may be formed of a pressure-sensitive adhesive of reduced adhesive strength.

As the radiation-curable pressure-sensitive adhesive in the pressure-sensitive adhesive layer 12, for example, a type of pressure-sensitive adhesive that is cured by irradiation with electron beam, ultraviolet ray, α ray, β ray, γ ray, or X ray can be used, and a type of pressure-sensitive adhesive that is cured by irradiation with ultraviolet ray (ultraviolet-curable pressure-sensitive adhesive) can be particularly suitably used.

Examples of the radiation-curable pressure-sensitive adhesive in the pressure-sensitive adhesive layer 12 include an additive type radiation-curable pressure-sensitive adhesive containing a base polymer such as an acrylic polymer as an acrylic pressure-sensitive adhesive, and a radiation-polymerizable monomer component and oligomer component having a functional group such as a radiation-polymerizable carbon-carbon double bond.

The acrylic polymer preferably contains a monomer unit derived from an acrylate and/or a methacrylate as a monomer unit having the largest mass ratio. "(meth) acrylic acid" means "acrylic acid" and/or "methacrylic acid".

Examples of the (meth) acrylate ester of the monomer unit for forming the acrylic polymer include: and hydrocarbon group-containing (meth) acrylates such as alkyl (meth) acrylates, cycloalkyl (meth) acrylates, and aryl (meth) acrylates. Examples of the alkyl (meth) acrylate include: methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, 2-ethylhexyl, isooctyl, nonyl, decyl, isodecyl, undecyl, dodecyl (i.e., lauryl), tridecyl, tetradecyl, hexadecyl, octadecyl, and eicosyl (meth) acrylates. Examples of the cycloalkyl (meth) acrylate include cyclopentyl and cyclohexyl (meth) acrylates. Examples of the aryl (meth) acrylate include: phenyl (meth) acrylate and benzyl (meth) acrylate. As the (meth) acrylate that is a monomer unit for forming the acrylic polymer, one kind of (meth) acrylate may be used, and two or more kinds of (meth) acrylates may also be used. Among the above, (meth) acrylic acid esters as monomer units for forming the acrylic polymer, alkyl (meth) acrylates having an alkyl group with 10 or more carbon atoms are preferred, and lauryl (meth) acrylate is more preferred. In addition, the proportion of the (meth) acrylate in the entire monomer components for forming the acrylic polymer is preferably 40 mass% or more, and more preferably 60 mass% or more, in order to suitably exhibit basic characteristics such as adhesiveness depending on the (meth) acrylate in the pressure-sensitive adhesive layer 12.

The acrylic polymer may contain a monomer unit derived from another monomer copolymerizable with the (meth) acrylic acid ester in order to modify its cohesive force, heat resistance, and the like. Examples of such other monomers include: a carboxyl group-containing monomer, an acid anhydride monomer, a hydroxyl group-containing monomer, a glycidyl group-containing monomer, a sulfonic acid group-containing monomer, a phosphoric acid group-containing monomer, acrylamide, acrylonitrile, and other functional group-containing monomers. Examples of the carboxyl group-containing monomer include: acrylic acid, methacrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of the acid anhydride monomer include maleic anhydride and itaconic anhydride. Examples of the hydroxyl group-containing monomer include: 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate, 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, and (4-hydroxymethylcyclohexyl) methyl (meth) acrylate. Examples of the glycidyl group-containing monomer include: glycidyl (meth) acrylate and methyl glycidyl (meth) acrylate. Examples of the sulfonic acid group-containing monomer include: styrenesulfonic acid, allylsulfonic acid, 2- (meth) acrylamido-2-methylpropanesulfonic acid, (meth) acrylamidopropanesulfonic acid, sulfopropyl (meth) acrylate, and (meth) acryloyloxynaphthalenesulfonic acid. Examples of the phosphoric acid group-containing monomer include: 2-hydroxyethyl acryloyl phosphate. As the other copolymerizable monomer used for the acrylic polymer, one kind of monomer may be used, or two or more kinds of monomers may be used. When the acrylic polymer contains a unit derived from an alkyl (meth) acrylate having an alkyl group of 10 or more carbon atoms (unit 1), it preferably contains a unit derived from 2-hydroxyethyl (meth) acrylate (unit 2). In such an acrylic polymer, the molar ratio of the 1 st unit to the 2 nd unit is preferably 1 or more, more preferably 3 or more, and further preferably 5 or more. The molar ratio is preferably 40 or less, more preferably 35 or less, and still more preferably 30 or less.

The acrylic polymer may contain a monomer unit derived from a polyfunctional monomer copolymerizable with a monomer component such as a (meth) acrylate ester in order to form a crosslinked structure in the polymer skeleton. Examples of such polyfunctional monomers include: hexanediol di (meth) acrylate, (poly) ethylene glycol di (meth) acrylate, (poly) propylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, epoxy (meth) acrylate (i.e., polyglycidyl (meth) acrylate), polyester (meth) acrylate, and urethane (meth) acrylate. As the polyfunctional monomer used for the acrylic polymer, one polyfunctional monomer may be used, or two or more polyfunctional monomers may be used. The ratio of the polyfunctional monomer in the total monomer components for forming the acrylic polymer is preferably 40% by mass or less, and more preferably 30% by mass or less, in order to suitably exhibit basic characteristics such as adhesiveness depending on the (meth) acrylate in the pressure-sensitive adhesive layer 12.

The acrylic polymer can be obtained by polymerizing a raw material monomer for forming the acrylic polymer. Examples of the polymerization method include: solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization. From the viewpoint of high cleanability of the semiconductor device manufacturing method using the dicing tape 10 and/or the dicing die-bonding film X, it is preferable that the low-molecular-weight substance in the pressure-sensitive adhesive layer 12 of the dicing tape 10 and/or the dicing die-bonding film X is small, and the number average molecular weight of the acrylic polymer is preferably 10 ten thousand or more, more preferably 20 ten thousand to 300 ten thousand.

The pressure-sensitive adhesive layer 12 and/or the pressure-sensitive adhesive used for forming the same may contain, for example, an external crosslinking agent in order to increase the number average molecular weight of a base polymer such as an acrylic polymer. Examples of the external crosslinking agent for forming a crosslinked structure by reacting with a base polymer such as an acrylic polymer include: polyisocyanate compounds, epoxy compounds, polyol compounds (such as polyphenol compounds), aziridine compounds, and melamine crosslinking agents. The content of the external crosslinking agent in the adhesive layer 12 and/or the adhesive for forming the same is preferably 5 parts by mass or less, and more preferably 0.1 to 5 parts by mass, relative to 100 parts by mass of the base polymer.

Examples of the radiation-polymerizable monomer component for forming a radiation-curable pressure-sensitive adhesive include: urethane (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and 1, 4-butanediol di (meth) acrylate. Examples of the radiation-polymerizable oligomer component for forming a radiation-curable pressure-sensitive adhesive include: various oligomers such as urethane type, polyether type, polyester type, polycarbonate type, polybutadiene type, etc., and those having a molecular weight of about 100 to 30000 are suitable. The total content of the radiation-polymerizable monomer component and oligomer component in the radiation-curable pressure-sensitive adhesive is determined within a range that can suitably reduce the adhesive strength of the pressure-sensitive adhesive layer 12 to be formed, and is, for example, 5 to 500 parts by mass, and preferably 40 to 150 parts by mass, based on 100 parts by mass of a base polymer such as an acrylic polymer. Further, as the additive type radiation curing adhesive, for example, one disclosed in Japanese patent application laid-open No. 60-196956 can be used.

Examples of the radiation-curable pressure-sensitive adhesive in the pressure-sensitive adhesive layer 12 include: an internal radiation-curable pressure-sensitive adhesive containing a base polymer having a functional group such as a radiation-polymerizable carbon-carbon double bond at a polymer side chain, a polymer main chain, or a polymer main chain end. Such an internal radiation-curable pressure-sensitive adhesive is suitable for suppressing an undesirable change in the pressure-sensitive adhesive properties with time due to the movement of low-molecular-weight components in the pressure-sensitive adhesive layer 12 to be formed.

The base polymer contained in the internal radiation-curable pressure-sensitive adhesive preferably has an acrylic polymer as a basic skeleton. As the acrylic polymer which becomes such a basic skeleton, the above-mentioned acrylic polymer can be used. Examples of the method for introducing a radiation-polymerizable carbon-carbon double bond into an acrylic polymer include the following methods: after a raw material monomer including a monomer having a predetermined functional group (1 st functional group) is copolymerized to obtain an acrylic polymer, a compound having a predetermined functional group (2 nd functional group) and a radiation-polymerizable carbon-carbon double bond, which are capable of bonding by reaction with the 1 st functional group, is subjected to a condensation reaction or an addition reaction with the acrylic polymer while maintaining the radiation-polymerizability of the carbon-carbon double bond.

Examples of the combination of the 1 st functional group and the 2 nd functional group include: carboxyl and epoxy group, epoxy and carboxyl, carboxyl and aziridine group, aziridine group and carboxyl, hydroxyl and isocyanate group, isocyanate group and hydroxyl. Among these combinations, a combination of a hydroxyl group and an isocyanate group, and a combination of an isocyanate group and a hydroxyl group are preferable from the viewpoint of easiness of reaction follow-up. Further, the technical difficulty in producing a polymer having a highly reactive isocyanate group is high, and from the viewpoint of easiness in producing or obtaining an acrylic polymer, it is more preferable that the 1 st functional group on the acrylic polymer side is a hydroxyl group and the 2 nd functional group is an isocyanate group. In this case, examples of the isocyanate compound having both a radiation-polymerizable carbon-carbon double bond and an isocyanate group serving as the 2 nd functional group, that is, a radiation-polymerizable unsaturated functional group-containing isocyanate compound include: methacryloyl isocyanate, 2-methacryloyloxyethyl isocyanate (MOI), and m-isopropenyl-alpha, alpha-dimethylbenzyl isocyanate. When the unsaturated functional group-containing isocyanate compound is introduced and/or added to the acrylic polymer, the molar ratio of the unsaturated functional group-containing isocyanate compound to the unit derived from 2-hydroxyethyl (meth) acrylate (unit No. 2) in the acrylic polymer is preferably 0.1 or more, more preferably 0.2 or more, and still more preferably 0.3 or more. In addition, in the reaction composition containing the unsaturated functional group-containing isocyanate compound and the acrylic polymer for forming an addition product obtained by adding the unsaturated functional group-containing isocyanate compound to the acrylic polymer, the molar ratio of the unsaturated functional group-containing isocyanate compound to the unit derived from 2-hydroxyethyl (meth) acrylate (unit No. 2) of the acrylic polymer is preferably 2 or less, more preferably 1.5 or less, and further preferably 1.3 or less.

The radiation-curable pressure-sensitive adhesive in the pressure-sensitive adhesive layer 12 preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include: an alpha-ketol compound, an acetophenone compound, a benzoin ether compound, a ketal compound, an aromatic sulfonyl chloride compound, a photoactive oxime compound, a benzophenone compound, a thioxanthone compound, camphorquinone, a halogenated ketone, an acyl phosphine oxide, and an acyl phosphonate. Examples of the α -ketol compound include: 4- (2-hydroxyethoxy) phenyl (2-hydroxy-2-propyl) ketone, α -hydroxy- α, α' -dimethylacetophenone, 2-methyl-2-hydroxypropiophenone, and 1-hydroxycyclohexyl phenyl ketone. Examples of the acetophenone-based compound include: methoxyacetophenone, 2-dimethoxy-1, 2-diphenylethan-1-one, 2-diethoxyacetophenone, and 2-methyl-1- [4- (methylthio) -phenyl ] -2-morpholinopropane-1. Examples of the benzoin ether-based compound include: benzoin ethyl ether, benzoin isopropyl ether, and anisoin methyl ether. Examples of the ketal compound include benzildimethylketal. Examples of the aromatic sulfonyl chloride compound include 2-naphthalenesulfonyl chloride. Examples of the photoactive oxime compound include: 1-phenyl-1, 2-propanedione-2- (O-ethoxycarbonyl) oxime. Examples of the benzophenone-based compound include: benzophenone, benzoylbenzoic acid, and 3,3' -dimethyl-4-methoxybenzophenone. Examples of the thioxanthone compound include: thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2, 4-dimethylthioxanthone, isopropylthioxanthone, 2, 4-dichlorothioxanthone, 2, 4-diethylthioxanthone, and 2, 4-diisopropylthioxanthone. The content of the photopolymerization initiator in the radiation-curable pressure-sensitive adhesive of the pressure-sensitive adhesive layer 12 is, for example, 0.05 to 20 parts by mass per 100 parts by mass of a base polymer such as an acrylic polymer.

When the heat-expandable pressure-sensitive adhesive in the pressure-sensitive adhesive layer 12 is a pressure-sensitive adhesive containing a component (a foaming agent, thermally expandable microspheres, or the like) which expands or foams by heating, examples of the foaming agent include various inorganic foaming agents and organic foaming agents, and examples of the thermally expandable microspheres include: microspheres made of a material that is easily vaporized by heating and expands are sealed in the shell. Examples of the inorganic foaming agent include: ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, ammonium nitrite, sodium borohydride, and azides. Examples of the organic foaming agent include: chlorofluoroalkanes such as trichlorofluoromethane and dichlorofluoromethane, azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate, hydrazine compounds such as p-toluenesulfonyl hydrazide, diphenylsulfone-3, 3 '-disulfonyl hydrazide, 4' -oxybis (benzenesulfonyl hydrazide), and allylbis (sulfonyl hydrazide), semicarbazide compounds such as p-toluenesulfonyl semicarbazide and 4,4 '-oxybis (benzenesulfonyl semicarbazide), triazole compounds such as 5-morpholinyl-1, 2,3, 4-thiatriazole, and N-nitroso compounds such as N, N' -dinitrosopentamethylenetetramine and N, N '-dimethyl-N, N' -dinitrosoterephthalamide. Examples of the material which is easily vaporized by heating and expanded to form the thermally expandable microspheres as described above include: isobutane, propane, and pentane. The thermally expandable microspheres can be produced by enclosing a substance which is easily vaporized by heating and expands in a shell-forming substance by an agglomeration method, an interfacial polymerization method, or the like. As the shell-forming substance, a substance exhibiting thermal fusion properties or a substance which can be broken by the thermal expansion action of the encapsulating substance can be used. Examples of such substances include: vinylidene chloride-acrylonitrile copolymers, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone.

Examples of the non-reducing adhesive strength adhesive include: a pressure-sensitive adhesive (a radiation-irradiated radiation-curable pressure-sensitive adhesive) in which the radiation-curable pressure-sensitive adhesive described in the adhesive force-reducing pressure-sensitive adhesive is cured by irradiation with radiation in advance. The radiation-curable pressure-sensitive adhesive irradiated with radiation has a reduced adhesive force due to radiation irradiation, but exhibits adhesive properties due to the polymer component depending on the content of the polymer component, and can exhibit adhesive force for adhesively holding an adherend in a predetermined use mode. In the pressure-sensitive adhesive layer 12 of the present embodiment, one kind of pressure-sensitive adhesive having a non-reduced adhesive strength may be used, or two or more kinds of pressure-sensitive adhesives having a non-reduced adhesive strength may be used. The entire pressure-sensitive adhesive layer 12 may be formed of a non-adhesive-force-reducing pressure-sensitive adhesive, or a part of the pressure-sensitive adhesive layer 12 may be formed of a non-adhesive-force-reducing pressure-sensitive adhesive. For example, when the pressure-sensitive adhesive layer 12 has a single-layer structure, the pressure-sensitive adhesive layer 12 may be entirely formed of a non-reduced-adhesive-force pressure-sensitive adhesive, or a predetermined portion of the pressure-sensitive adhesive layer 12 may be formed of a non-reduced-adhesive-force pressure-sensitive adhesive, and the other portion may be formed of a reduced-adhesive-force pressure-sensitive adhesive. When the pressure-sensitive adhesive layer 12 has a laminated structure, all layers forming the laminated structure may be formed of a non-adhesive-force-reducing pressure-sensitive adhesive, or some layers in the laminated structure may be formed of a non-adhesive-force-reducing pressure-sensitive adhesive.

On the other hand, as the pressure-sensitive adhesive in the adhesive layer 12, for example, an acrylic adhesive or a rubber adhesive containing an acrylic polymer as a base polymer can be used. When the pressure-sensitive adhesive layer 12 contains an acrylic pressure-sensitive adhesive as the pressure-sensitive adhesive, the acrylic polymer serving as a base polymer of the acrylic pressure-sensitive adhesive preferably contains a monomer unit derived from a (meth) acrylate as a monomer unit having the largest mass ratio. Examples of such an acrylic polymer include those described for the radiation-curable pressure-sensitive adhesive.

The pressure-sensitive adhesive layer 12 and/or the pressure-sensitive adhesive used for forming the same may further contain a crosslinking accelerator, a thickener, an antioxidant, a pigment, a colorant such as a dye, and the like in addition to the above components. The colorant may be a compound colored by being irradiated with radiation. Examples of such compounds include leuco dyes.

The pressure-sensitive adhesive layer 12 preferably has a thickness of 32mJ/m on the pressure-sensitive adhesive surface 12a forming the interface with the pressure-sensitive adhesive layer 20²Less, more preferably 30mJ/m²Hereinafter, more preferably 28mJ/m²The following surface free energy (2 nd surface free energy), or, can have a preferred 32mJ/m²Less, more preferably 30mJ/m²Hereinafter, more preferably 28mJ/m²The following surface free energy (2 nd surface free energy). When the pressure-sensitive adhesive layer 12 is a curable pressure-sensitive adhesive layer such as a radiation curable pressure-sensitive adhesive layer, the 2 nd surface free energy of the cured pressure-sensitive adhesive layer 12 is preferably 32mJ/m²Below, more preferably 30mJ/m²Hereinafter, more preferably 28mJ/m²The following. The pressure-sensitive adhesive layer 12 preferably has a thickness of 15mJ/m on the pressure-sensitive adhesive surface 12a forming the interface with the pressure-sensitive adhesive layer 20²More preferably 18mJ/m or more²Above, more preferably 20mJ/m²The above surface free energy (2 nd surface free energy), or, can have a preferred value of 15mJ/m²More preferably 18mJ/m or more²Above, more preferably 20mJ/m²The above surface free energy (2 nd surface free energy). When the pressure-sensitive adhesive layer 12 is a curable pressure-sensitive adhesive layer such as a radiation curable pressure-sensitive adhesive layer, the 2 nd surface free energy of the cured pressure-sensitive adhesive layer 12 is preferably 15mJ/m²More preferably 18mJ/m or more²More preferably 20mJ/m or more²The above. For adhesivesThe surface free energy of the pressure-sensitive adhesive surface 12a of the layer 12 can be adjusted by adjusting the composition of each monomer used for forming a base polymer such as an acrylic polymer in the pressure-sensitive adhesive layer 12.

The thickness of the adhesive layer 12 is preferably 1 to 50 μm, more preferably 2 to 30 μm, and further preferably 5 to 25 μm. Such a configuration is preferable in that, for example, when the pressure-sensitive adhesive layer 12 contains a radiation-curable pressure-sensitive adhesive, the balance of the adhesive force of the pressure-sensitive adhesive layer 12 to the adhesive layer 20 before and after radiation curing is obtained.

The adhesive layer 20 of the dicing die-bonding film X has both a function as an adhesive exhibiting thermosetting properties for die bonding and an adhesive function for holding a workpiece such as a semiconductor wafer and a frame member such as a ring frame. In the present embodiment, the adhesive agent for forming the adhesive layer 20 may have a composition containing a thermosetting resin and a thermoplastic resin as an adhesive component, for example, or may have a composition containing a thermoplastic resin having a thermosetting functional group that can react with a curing agent to bond. When the adhesive agent used to form the adhesive layer 20 has a composition containing a thermoplastic resin having a thermosetting functional group, the adhesive agent does not need to further contain a thermosetting resin (epoxy resin or the like). Such an adhesive layer 20 may have a single-layer structure or a multi-layer structure.

When the adhesive layer 20 contains a thermoplastic resin and a thermosetting resin, examples of the thermosetting resin include: epoxy resins, phenol resins, amino resins, unsaturated polyester resins, polyurethane resins, silicone resins, and thermosetting polyimide resins. One kind of thermosetting resin may be used or two or more kinds of thermosetting resins may be used in forming the adhesive layer 20. The thermosetting resin contained in the adhesive layer 20 is preferably an epoxy resin because of a tendency to have a low content of ionic impurities or the like that may cause corrosion of the semiconductor chip to be die-bonded. As the curing agent for the epoxy resin, a phenol resin is preferable.

Examples of the epoxy resin include: bisphenol A type, bisphenol F type, bisphenol S type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol AF type, biphenyl type, naphthalene type, fluorene type, phenol novolac type, o-cresol novolac type, trishydroxyphenylmethane type, tetrahydroxyphenylethane type, hydantoin type, triglycidyl isocyanurate type, and glycidylamine type epoxy resins. The novolac epoxy resin, the biphenyl epoxy resin, the trihydroxyphenylmethane epoxy resin, and the tetrahydroxyphenylethane epoxy resin are preferable as the epoxy resin contained in the adhesive layer 20 because they are rich in reactivity with the phenolic resin as the curing agent and have excellent heat resistance.

Examples of the phenolic resin which can function as a curing agent for an epoxy resin include: novolak-type phenol resins, resol-type phenol resins, and polyoxystyrenes such as polyoxystyrenes. Examples of the novolak phenol resin include: phenol novolac resins, phenol aralkyl resins, cresol novolac resins, tert-butylphenol novolac resins, and nonylphenol novolac resins. As the phenol resin which can function as a curing agent for the epoxy resin, one kind of phenol resin may be used, or two or more kinds of phenol resins may be used. Phenol novolac resin and phenol aralkyl resin tend to improve the connection reliability of an epoxy resin used as an adhesive for die bonding when used as a curing agent for the epoxy resin, and therefore are preferred as the curing agent for the epoxy resin contained in the adhesive layer 20.

In the adhesive layer 20, the phenolic resin is contained in an amount such that the hydroxyl group in the phenolic resin is preferably 0.5 to 2.0 equivalents, more preferably 0.8 to 1.2 equivalents, to 1 equivalent of the epoxy group in the epoxy resin component, from the viewpoint of sufficiently advancing the curing reaction between the epoxy resin and the phenolic resin.

Examples of the thermoplastic resin contained in the adhesive layer 20 include: natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, an ethylene-vinyl acetate copolymer, an ethylene-acrylic acid ester copolymer, a polybutadiene resin, a polycarbonate resin, a thermoplastic polyimide resin, a polyamide resin such as 6-nylon or 6, 6-nylon, a phenoxy resin, an acrylic resin, a saturated polyester resin such as PET or PBT, a polyamideimide resin, and a fluororesin. One kind of thermoplastic resin may be used for forming the adhesive layer 20, or two or more kinds of thermoplastic resins may be used. The thermoplastic resin contained in the adhesive layer 20 is preferably an acrylic resin because it has few ionic impurities and high heat resistance and it is easy to ensure the bonding reliability by the adhesive layer 20. In addition, from the viewpoint of compatibility between the adhesion of the adhesive layer 20 to the ring frame at room temperature and a temperature in the vicinity thereof, which will be described later, and the prevention of residues at the time of peeling, the adhesive layer 20 preferably contains a polymer having a glass transition temperature of-10 to 10 ℃ as a main component of the thermoplastic resin. The main component of the thermoplastic resin is a resin component that accounts for the largest mass ratio among the thermoplastic resin components.

As the glass transition temperature of the polymer, a glass transition temperature (theoretical value) obtained based on the following Fox equation can be used. The Fox equation is a relationship between the glass transition temperature Tg of a polymer and the glass transition temperature Tgi of a homopolymer of each constituent monomer in the polymer. In the following Fox formula, Tg represents the glass transition temperature (. degree. C.) of the polymer, Wi represents the weight percentage of the monomer i constituting the polymer, and Tgi represents the glass transition temperature (. degree. C.) of the homopolymer of the monomer i. The glass transition temperature of the homopolymer can be determined from literature values, for example, the glass transition temperatures of various homopolymers are listed in "synthetic resin for paint of New Polymer library 7" (North oka Co., Ltd., Polymer journal, 1995) "and" catalogues of acrylic esters (1997 edition) "(Mitsubishi Yang corporation). On the other hand, the glass transition temperature of a homopolymer of a monomer can be determined by the method specifically described in Japanese patent laid-open No. 2007-51271.

Fox formula 1/(273+ Tg) ═ Σ [ Wi/(273+ Tgi) ]

The acrylic resin contained as the thermoplastic resin in the adhesive layer 20 preferably contains a monomer unit derived from a (meth) acrylate ester as a main monomer unit having the largest mass ratio. As such a (meth) acrylate, for example, the same (meth) acrylate as described in the acrylic polymer which is one component of the radiation-curable pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 12 can be used. The acrylic resin contained as the thermoplastic resin in the adhesive layer 20 may contain a monomer unit derived from another monomer copolymerizable with the (meth) acrylate. Examples of such other monomer components include: the carboxyl group-containing monomer, the acid anhydride monomer, the hydroxyl group-containing monomer, the glycidyl group-containing monomer, the sulfonic acid group-containing monomer, the phosphoric acid group-containing monomer, the functional group-containing monomer such as acrylamide and acrylonitrile, and various polyfunctional monomers can be used, and specifically, the same ones as those described as other monomers copolymerizable with the (meth) acrylic acid ester in the acrylic polymer which is one component of the radiation curing type pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 12 can be used. From the viewpoint of achieving a high cohesive force of the adhesive layer 20, the acrylic resin contained in the adhesive layer 20 is preferably a copolymer of a (meth) acrylate (particularly, an alkyl (meth) acrylate in which the alkyl group has 4 or less carbon atoms), a carboxyl group-containing monomer, a nitrogen atom-containing monomer, and a polyfunctional monomer (particularly, a polyglycidyl polyfunctional monomer), and more preferably a copolymer of ethyl acrylate, butyl acrylate, acrylic acid, acrylonitrile, and polyglycidyl (meth) acrylate.

The content ratio of the thermosetting resin in the adhesive layer 20 is preferably 5 to 60% by mass, and more preferably 10 to 50% by mass, from the viewpoint of suitably exhibiting the function as a thermosetting adhesive in the adhesive layer 20.

When the adhesive layer 20 contains a thermoplastic resin having a thermosetting functional group, an acrylic resin having a thermosetting functional group can be used as the thermoplastic resin, for example. The acrylic resin used for forming the thermosetting functional group-containing acrylic resin preferably contains a monomer unit derived from a (meth) acrylate ester as a main monomer unit having the largest mass ratio. As such a (meth) acrylate, for example, the same (meth) acrylate as described in the acrylic polymer which is one component of the radiation curing type pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 12 can be used. On the other hand, examples of the thermosetting functional group used for forming the thermosetting functional group-containing acrylic resin include glycidyl groups, carboxyl groups, hydroxyl groups, and isocyanate groups. Among them, glycidyl groups and carboxyl groups can be suitably used. That is, as the thermosetting functional group-containing acrylic resin, a glycidyl group-containing acrylic resin or a carboxyl group-containing acrylic resin can be suitably used. As the curing agent for the thermosetting functional group-containing acrylic resin, for example, those described as external crosslinking agents which are sometimes regarded as one component of a radiation-curable pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer 12 can be used. When the thermosetting functional group in the thermosetting functional group-containing acrylic resin is a glycidyl group, a polyphenol compound can be suitably used as the curing agent, and for example, the above-mentioned various phenol resins can be used.

In order to achieve a certain degree of crosslinking in the adhesive layer 20 before curing for die bonding, for example, a polyfunctional compound capable of reacting with and bonding to a functional group at a molecular chain end of the resin contained in the adhesive layer 20 is preferably blended in advance as a crosslinking agent in the adhesive layer-forming resin composition. Such a configuration is preferable in terms of improving the adhesive properties of the adhesive layer 20 at high temperatures and in terms of improving the heat resistance. Examples of such a crosslinking agent include polyisocyanate compounds. Examples of the polyisocyanate compound include: toluene diisocyanate, diphenylmethane diisocyanate, p-phenylene diisocyanate, 1, 5-naphthalene diisocyanate, and an adduct of a polyol and a diisocyanate. The content of the crosslinking agent in the resin composition for forming an adhesive layer is preferably 0.05 parts by mass or more in terms of increasing the cohesive force of the formed adhesive layer 20 and preferably 7 parts by mass or less in terms of increasing the adhesive force of the formed adhesive layer 20, relative to 100 parts by mass of the resin having the functional group capable of reacting with and bonding to the crosslinking agent. As the crosslinking agent in the adhesive layer 20, other polyfunctional compounds such as epoxy resins can be used in combination with the polyisocyanate compound.

The content ratio of the high molecular weight component in the adhesive layer 20 is preferably 50 to 100% by mass, and more preferably 50 to 80% by mass. The high molecular weight component is a component having a weight average molecular weight of 10000 or more. Such a configuration is preferable in terms of achieving both adhesiveness of the adhesive layer 20 to the later-described ring frame at room temperature and a temperature in the vicinity thereof and preventing residues at the time of peeling. Further, the adhesive layer 20 may contain a liquid resin that is liquid at 23 ℃. When the adhesive layer 20 contains such a liquid resin, the content of the liquid resin in the adhesive layer 20 is preferably 1 to 10% by mass, and more preferably 1 to 5% by mass. Such a configuration is preferable in terms of achieving both adhesiveness of the adhesive layer 20 to the later-described ring frame at room temperature and a temperature in the vicinity thereof and preventing residues at the time of peeling.

Adhesive layer 20 may contain a filler. By adding the filler to the adhesive layer 20, physical properties such as elastic modulus such as tensile storage modulus, electrical conductivity, and thermal conductivity of the adhesive layer 20 can be adjusted. Examples of the filler include an inorganic filler and an organic filler, and the inorganic filler is particularly preferable. Examples of the inorganic filler include: aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum nitride, aluminum borate whisker, boron nitride, crystalline silica, amorphous silica, and a simple metal such as aluminum, gold, silver, copper, and nickel, an alloy, amorphous carbon black, and graphite. The filler may have various shapes such as a spherical shape, a needle shape, and a flake shape. As the filler in the adhesive layer 20, one kind of filler may be used, or two or more kinds of fillers may be used. The content ratio of the filler in the adhesive layer 20 is preferably 30 mass% or less, and more preferably 25 mass% or less, in order to ensure adhesion of the adhesive layer 20 to the ring frame in the cooling expansion step described later.

When the adhesive layer 20 contains a filler, the average particle diameter of the filler is preferably 0.005 to 10 μm, and more preferably 0.005 to 1 μm. The filler having an average particle diameter of 0.005 μm or more is preferably used in order to achieve high wettability and adhesiveness of the adhesive layer 20 to an adherend such as a semiconductor wafer. The filler having an average particle diameter of 10 μm or less is preferably used in order to obtain a sufficient filler addition effect to the adhesive layer 20 and to ensure heat resistance. The average particle diameter of the filler is determined, for example, by using a photometric particle size distribution meter (trade name "LA-910", manufactured by horiba, Ltd.).

Adhesive layer 20 may contain other components as needed. Examples of the other components include: a flame retardant, a silane coupling agent, and an ion trapping agent. Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resins. Examples of the silane coupling agent include: beta- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane, gamma-glycidoxypropyltrimethoxysilane, and gamma-glycidoxypropylmethyldiethoxysilane. Examples of the ion scavenger include: hydrotalcite, bismuth hydroxide, antimony oxide hydrate (for example, "IXE-300" manufactured by east asian synthesis corporation), zirconium phosphate having a specific structure (for example, "IXE-100" manufactured by east asian synthesis corporation), magnesium silicate (for example, "Kyoward 600" manufactured by synechiae chemical industry co., ltd.), and aluminum silicate (for example, "Kyoward 700" manufactured by synechiae chemical industry co., ltd.). A compound capable of forming a complex with a metal ion may be used as the ion scavenger. Examples of such compounds include: triazole-based compounds, tetrazole-based compounds, and bipyridine-based compounds. Among them, from the viewpoint of stability of a complex formed with a metal ion, a triazole-based compound is preferable. Examples of such triazole-based compounds include: 1,2, 3-benzotriazole, 1- { N, N-bis (2-ethylhexyl) aminomethyl } benzotriazole, carboxybenzotriazole, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-3, 5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3-tert-butyl-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3, 5-di-tert-amylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 6- (2-benzotriazolyl) -4-tert-octyl-6 '-tert-butyl-4' -methyl-2, 2' -methylenebisphenol, 1- (2, 3-dihydroxypropyl) benzotriazole, 1- (1, 2-dicarboxydiethyl) benzotriazole, 1- (2-ethylhexylaminomethyl) benzotriazole, 2, 4-di-t-amyl-6- { (H-benzotriazol-1-yl) methyl } phenol, 2- (2-hydroxy-5-t-butylphenyl) -2H-benzotriazole, octyl-3- [ 3-t-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazol-2-yl) phenyl ] propionate, 2-ethylhexyl-3- [ 3-t-butyl-4-hydroxy-5- (5-chloro-2H-benzotriazol-2-) Phenyl ] propionate, 2- (2H-benzotriazol-2-yl) -6- (1-methyl-1-phenylethyl) -4- (1,1,3, 3-tetramethylbutyl) phenol, 2- (2H-benzotriazol-2-yl) -4-tert-butylphenol, 2- (2-hydroxy-5-methylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) -benzotriazole, 2- (3-tert-butyl-2-hydroxy-5-methylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3, 5-di-tert-amylphenyl) benzotriazole, and mixtures thereof, 2- (2-hydroxy-3, 5-di-tert-butylphenyl) -5-chloro-benzotriazole, 2- [ 2-hydroxy-3, 5-bis (1, 1-dimethylbenzyl) phenyl ] -2H-benzotriazole, 2' -methylenebis [6- (2H-benzotriazol-2-yl ] -4- (1,1,3, 3-tetramethylbutyl) phenol ], 2- [ 2-hydroxy-3, 5-bis (. alpha.,. alpha. -dimethylbenzyl) phenyl ] -2H-benzotriazole, and methyl-3- [3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl ] propionate in addition, predetermined hydroxyl group-containing compounds such as hydroquinone compounds, hydroxyanthraquinone compounds, polyphenol compounds and the like can also be used as the ion scavenger. Specific examples of such a hydroxyl group-containing compound include: 1, 2-benzenediol, alizarin, 1, 5-dihydroxy anthraquinone, tannic acid, gallic acid, methyl gallate, pyrogallol and the like. As the other components, one component may be used, or two or more components may be used.

The thickness of the adhesive layer 20 is, for example, in the range of 1 to 200 μm. The upper limit of the thickness is preferably 100 μm, more preferably 80 μm. The lower limit of the thickness is preferably 3 μm, more preferably 5 μm.

The surface free energy (1 st surface free energy) of the surface 20b of the adhesive layer 20 forming the interface with the adhesive layer 12 is preferably 30mJ/m²Above, more preferably 31mJ/m²More preferably 32mJ/m²The above. Further, the 1 st surface free energy is preferably 45mJ/m²Hereinafter, more preferably 43mJ/m²The lower, more preferably 40mJ/m²The following.

The adhesive layer 20 was peeled at a peeling angle of 180 degrees and a stretching speed of 10 mm/min at 23 DEG CIn a peel test under the bell condition, the adhesive strength at 180 DEG peel of 0.1N/10mm or more, more preferably 0.3N/10mm or more, and still more preferably 0.5N/10mm or more, to the SUS plane is exhibited. The adhesive layer 20 exhibits a 180 ° peel adhesion to the SUS plane in a peel test under the same conditions, preferably 20N/10mm or less, more preferably 10N/10mm or less. The 180 DEG peel adhesion can be measured by using a tensile tester (trade name "Autograph AGS-J", manufactured by Shimadzu corporation). The sample piece used for the measurement can be produced as follows. First, a laminate having a laminated structure of the base material 11, the adhesive layer 12 and the adhesive layer 20, and having a width of 10mm × a length of 100mm, is cut out from the dicing die-bonding film X. When the pressure-sensitive adhesive layer 12 is of an ultraviolet-curable type, the dicing die-bonding film X is irradiated with 350mJ/cm of light from the substrate 11 side to the pressure-sensitive adhesive layer 12²The adhesive layer 12 is cured by the ultraviolet rays of (3), and then the laminate is cut. Subsequently, the adhesive layer 20 side of the laminate was bonded to a silicon wafer by pressure bonding work of reciprocating a 2kg roller 1 time at 60 ℃, and then the bonded body was left at 60 ℃ for 2 minutes. Next, the pressure-sensitive adhesive layer 12 and the base material 11 are peeled from the pressure-sensitive adhesive layer 20 on the silicon wafer. Then, a liner tape (product name "BT-315", manufactured by ritonao electric corporation) was attached to the adhesive layer 20 remaining on the silicon wafer, and the adhesive layer 20 was peeled off from the silicon wafer, so that the adhesive layer 20 was transferred from the silicon wafer to the liner tape. In the above manner, adhesive layer test pieces (width 10 mm. times. length 100mm) with a backing tape were prepared. The sample piece was attached to a SUS plate as an adherend by 1-time pressure-bonding operation in which a 2kg roller was reciprocated.

The tensile storage modulus at 23 ℃ of the adhesive layer 20, measured under the conditions of the distance between the initial clamps of 10mm, the frequency of 10Hz, the dynamic strain. + -. 0.5 μm, and the temperature increase rate of 5 ℃/min for a sample sheet of the adhesive layer 20 having a width of 4mm and a thickness of 80 μm, is preferably 100MPa or more, more preferably 500MPa or more, and still more preferably 1000MPa or more. The tensile storage modulus at 23 ℃ of the adhesive layer 20 measured under the same conditions is preferably 4000MPa or less, more preferably 3000MPa or less, and still more preferably 2000MPa or less. The tensile storage modulus can be determined based on a dynamic viscoelasticity measurement performed using a dynamic viscoelasticity measurement apparatus (trade name "Rheogel-E4000", manufactured by UBM). In this measurement, the dimensions of the sample piece as the object of measurement were set to 4mm in width, 20mm in length, and 80 μm in thickness, the initial inter-jig distance of the sample piece holding jig was set to 10mm, the measurement mode was set to the tensile mode, the measurement temperature range was-30 ℃ to 100 ℃, the frequency was set to 10Hz, the dynamic strain was ± 0.5 μm, and the temperature rise rate was set to 5 ℃/min.

In the present embodiment, the outer peripheral end 20e of the adhesive layer 20 is located at a distance of 1000 μm or less, preferably 500 μm or less from the outer peripheral end 11e of the base material 11 and the outer peripheral end 12e of the adhesive layer 12 in the dicing tape 10 in the in-plane direction D of the dicing die-bonding film X. That is, the entire periphery of the outer peripheral end 20e of the adhesive layer 20 is located between 1000 μm inside and 1000 μm outside, preferably between 500 μm inside and 500 μm outside, of the outer peripheral end 11e of the base material 11 in the film in-plane direction D, and is located between 1000 μm inside and 1000 μm outside, preferably between 500 μm inside and 500 μm outside, of the outer peripheral end 12e of the pressure-sensitive adhesive layer 12. In this configuration in which the dicing tape 10 and/or the pressure-sensitive adhesive layer 12 thereof and the adhesive layer 20 thereon have substantially the same dimensions in the in-plane direction D, the adhesive layer 20 includes the frame member attachment region on the surface 20a side in addition to the work attachment region, as described above.

In the dicing die-bonding film X, when the pressure-sensitive adhesive layer 12 of the dicing tape 10 is a radiation-curable pressure-sensitive adhesive layer, the peel force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 after radiation curing in a T-peel test at 23 ℃ and a peel speed of 300 mm/min is preferably 0.06N/20mm or more, more preferably 0.1N/20mm or more, and still more preferably 0.15N/20mm or more. The peel force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 after radiation curing in a T-peel test at 23 ℃ and a peel speed of 300 mm/min is preferably 0.25N/20mm or less, more preferably 0.23N/20mm or less, and still more preferably 0.2N/20mm or less. The peeling force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 before radiation curing in the T-peel test at 23 ℃ and a peeling speed of 300 mm/min is preferably 2N/20mm toThe above. The T-peel test can be performed using a tensile tester (trade name "Autograph AGS-J", manufactured by Shimadzu corporation). The test piece used in this test was prepared as follows. First, the dicing die-bonding film X was irradiated with 350mJ/cm of the pressure-sensitive adhesive layer 12 from the substrate 11 side²The adhesive layer 12 is cured. Subsequently, a backing tape (trade name "BT-315", manufactured by rito electrical corporation) was attached to the adhesive layer 20 side of the dicing die-bonding film X, and then a sample piece having a width of 50mm × a length of 120mm was cut out.

The difference in arithmetic average surface roughness (Ra) between the surface of the pressure-sensitive adhesive layer 12 and the surface of the pressure-sensitive adhesive layer 20, which are used to form the interface between the pressure-sensitive adhesive layer 12 and the pressure-sensitive adhesive layer 20 in the dicing die-bonding film X, is preferably 100nm or less.

The dicing die-bonding film X may be provided with a separator S as shown in fig. 2. Specifically, the cut die bonding film X may have a sheet shape with the separator S for each cut die bonding film X, or may have a long separator S, and a plurality of cut die bonding films X may be arranged thereon and the separator S may be wound and formed into a roll. The separator S is a member for protecting the surface of the adhesive layer 20 of the dicing die-bonding film X by coating, and is peeled off when the dicing die-bonding film X is used. Examples of the separator S include: polyethylene terephthalate (PET) films, polyethylene films, polypropylene films, plastic films surface-coated with a release agent such as a fluorine-based release agent or a long-chain alkyl acrylate-based release agent, paper, and the like. The thickness of the spacer S is, for example, 5 to 200 μm.

The dicing die-bonding film X having the above-described structure can be manufactured, for example, as follows.

First, as shown in fig. 3 (a), an adhesive composition layer C1 is formed on a long separator S. Adhesive composition layer C1 can be formed by coating the adhesive composition prepared for forming adhesive layer 20 on separator S. Examples of the method for applying the adhesive composition include: roll coating, screen coating, and gravure coating.

Next, as shown in fig. 3 (b), an adhesive composition layer C2 is formed on the adhesive composition layer C1. The adhesive composition layer C2 may be formed by coating the adhesive composition prepared for forming the adhesive layer 12 on the adhesive composition layer C1. Examples of the method for applying the adhesive composition include: roll coating, screen coating, and gravure coating.

Then, the adhesive layer 20 'and the adhesive layer 12' are formed on the separator S by the primary heat treatment of the adhesive composition layer C1 and the adhesive composition layer C2. In this heat treatment, the two layers are dried as necessary, and the two layers are subjected to a crosslinking reaction as necessary. The heating temperature is, for example, 60 to 175 ℃ and the heating time is, for example, 0.5 to 5 minutes. Adhesive layer 20' is a material to be processed into adhesive layer 20. The adhesive layer 12' is a material to be processed to form the adhesive layer 12 described above.

Next, as shown in fig. 3 (c), the substrate 11 'is pressure-bonded to the pressure-sensitive adhesive layer 12'. The substrate 11' is a material to be processed and formed into the above-described substrate 11. The resin substrate 11' can be produced by a film-forming method such as a calendering film-forming method, a casting method in an organic solvent, a inflation extrusion method in a closed system, a T-die extrusion method, a co-extrusion method, or a dry lamination method. The film and/or the substrate 11' after the film formation is subjected to a predetermined surface treatment as necessary. In this step, the bonding temperature is, for example, 30 to 50 ℃, preferably 35 to 45 ℃. The bonding pressure (linear pressure) is, for example, 0.1 to 20kgf/cm, preferably 1 to 10 kgf/cm. By this step, a long laminated sheet body having a laminated structure of the separator S, the adhesive layer 20', the adhesive layer 12', and the base material 11' can be obtained.

Next, as shown in fig. 3 d, the laminated sheet body is processed by a processing blade from the substrate 11' side until the processing blade reaches the spacer S (the cutting position is schematically shown by a thick line in fig. 3 d). For example, while the laminated sheet body is moved at a fixed speed in one direction F, a machining blade-attached surface of a machining blade-attached rotating roll (not shown) which is disposed so as to be rotatable about an axial center orthogonal to the direction F and has a machining blade attached to a roll surface thereof for punching is brought into contact with the base material 11' side of the laminated sheet body with a predetermined pressing force. In this way, the dicing tape 10 (base material 11, adhesive layer 12) and adhesive layer 20 are processed and formed at one time, and the dicing die-bonding film X is formed on the separator S. Then, as shown in fig. 3 (e), the material laminated portion around the dicing die-bonding film X is removed from the spacer S.

In the above operation, the dicing die-bonding film X can be manufactured.

In the manufacturing process of a semiconductor device, as described above, in order to obtain a semiconductor chip with an adhesive layer, there are cases where a spreading step of bonding a film using a dicing die and a picking-up step are performed, and in the picking-up step, it is necessary to be able to peel the adhesive layer of the semiconductor chip with the adhesive layer from the adhesive layer and pick up the semiconductor chip from a dicing tape. The present inventors have obtained the following findings: the difference between the 1 st and 2 nd surface free energies at the interface between the pressure-sensitive adhesive layer 12 and the pressure-sensitive adhesive layer 20 of the dicing die-bonding film X of the present invention is 3.5mJ/m²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above state is suitable for achieving good pickup by the pickup process. Specifically, the examples and comparative examples are shown below. At the interface between the pressure-sensitive adhesive layer 12 and the pressure-sensitive adhesive layer 20, the greater the difference between the surface free energy of the pressure-sensitive adhesive surface 12a of the pressure-sensitive adhesive layer 12 and the surface free energy of the surface 20b of the pressure-sensitive adhesive layer 20, the more difficult the constituent materials between the two layers are to be transferred. Further, the constituent material between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 is not easily transferred, and is suitable for realizing a small peeling force between the two layers. The difference between the 1 st and 2 nd surface free energies at the interface between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 is 3.5mJ/m²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above configuration is suitable for ensuring a small peeling force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 to such an extent that good pick-up of the semiconductor chip with the adhesive layer can be achieved by the pick-up process.

Dicing die-bonding film X suitable for suppressing increase in peeling force between adhesive layer 12 and adhesive layer 20 ensures that the frame structure is secured by reducing elasticity of adhesive layer 20The adhesive strength of the material can be designed such that the dicing tape 10 and/or the adhesive layer 12 thereof and the adhesive layer 20 thereon have substantially the same dimension in the film in-plane direction so that the adhesive layer 20 includes the frame member bonding region in addition to the workpiece bonding region. Specifically, as described above, the following design can be adopted: in the in-plane direction of the dicing die-bonding film X, the outer peripheral end 20e of the adhesive layer 20 is located at a distance of 1000 μm or less, preferably 500 μm or less from the outer peripheral end 11e of the base material 11 of the dicing tape 10 and the outer peripheral end 12e of the adhesive layer 12. Such a dicing die-bonding film X is suitable for performing processing for forming one dicing tape 10 having a laminated structure of a base material 11 and an adhesive layer 12 and processing for forming one adhesive layer 20 at a time by processing such as one-time punching processing. Such a dicing die-bonding film X is suitable for efficient production from the viewpoints of reducing the number of production steps, suppressing the production cost, and the like. In addition, in the above-mentioned production method in which the composition for forming an adhesive layer and the composition for forming an adhesive layer are laminated and the two composition layers are once dried, the peeling force between the two layers is likely to increase at the interface between the adhesive layer and the adhesive layer, and the difference between the 1 st and 2 nd surface free energies at the interface between the adhesive layer 12 and the adhesive layer 20 is 3.5mJ/m as described above, as compared with the production method in which the adhesive layer and the adhesive layer are formed separately and then bonded to each other²Above, preferably 4mJ/m²More preferably 5mJ/m or more²The above configuration is suitable for ensuring a small peeling force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 to such an extent that good pick-up of the semiconductor chip with the adhesive layer can be achieved by the pick-up process.

As described above, the dicing die-bonding film X is suitable for achieving good pick-up of the semiconductor chip with the adhesive layer from the dicing tape 10.

The adhesive layer 12 in the dicing die-bonding film X is constituted as described above in the following manner: the adhesive surface 12a forming the interface with the adhesive layer 20 can have a thickness of 32mJ/m²Less, more preferably 30mJ/m²Hereinafter, more preferably 28mJ/m²Surface free energy of (2 nd surface)Free energy). This configuration is preferable in terms of ensuring the above-described small peeling force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 of the dicing die-bonding film X. Further, the adhesive layer 12 is configured as described above in the following manner: the adhesive surface 12a forming the interface with the adhesive layer 20 can have a thickness of preferably 15mJ/m²More preferably 18mJ/m or more²Above, more preferably 20mJ/m²The above surface free energy (2 nd surface free energy). This configuration is preferable, for example, from the viewpoint of ensuring a suitable adhesive force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 so that peeling does not occur between the two layers during conveyance of the dicing die-bonding film X.

The above-mentioned 1 st surface free energy of the adhesive layer 20 for dicing the die-bonding film X is preferably 30mJ/m as described above²Above, more preferably 31mJ/m²More preferably 32mJ/m²The above. This configuration is preferable in terms of ensuring the required adhesion force between the adhesive layer 20 and the pressure-sensitive adhesive layer 12. Further, the 1 st surface free energy is preferably 45mJ/m²Hereinafter, more preferably 43mJ/m²The lower, more preferably 40mJ/m²The following. This configuration is preferable in terms of ensuring the above-described small peeling force between the adhesive layer 20 and the pressure-sensitive adhesive layer 12.

The adhesive layer 20 exhibits a 180 ° peel adhesion to the SUS plane of 0.1N/10mm or more, more preferably 0.3N/10mm or more, and still more preferably 0.5N/10mm or more, in a peel test under conditions of 23 ℃, a peel angle of 180 ° and a tensile speed of 10 mm/min, as described above. This configuration is suitable for ensuring the holding of the frame member by the dicing die-bonding film X. The adhesive layer 20 exhibits a 180 ° peel adhesion to the SUS plane of preferably 20N/10mm or less, more preferably 10N/10mm or less, in a peel test under the same conditions as described above. This configuration is preferable in terms of ensuring the detachability of the frame member from the dicing die-bonding film X.

As described above, the tensile storage modulus at 23 ℃ of the adhesive layer 20 measured on a sample sheet of the adhesive layer 20 having a width of 4mm and a thickness of 80 μm under the conditions of a distance between the initial jigs of 10mm, a frequency of 10Hz, a dynamic strain. + -. 0.5 μm, and a temperature rise rate of 5 ℃/min is preferably 100MPa or more, more preferably 500MPa or more, and still more preferably 1000MPa or more. This configuration is suitable for securing the adhesive force of the adhesive layer 20 to the frame member, and is therefore suitable for securing the holding of the frame member by the dicing die-bonding film X. The tensile storage modulus at 23 ℃ of the adhesive layer 20 measured under the same conditions as described above is preferably 4000MPa or less, more preferably 3000MPa or less, and still more preferably 2000MPa or less. This configuration is preferable in terms of ensuring the detachability of the frame member from the dicing die-bonding film X.

In the dicing die-bonding film X, when the pressure-sensitive adhesive layer 12 of the dicing tape 10 is the radiation-curable pressure-sensitive adhesive layer 12, the peel force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 after radiation curing in the T-type peel test under the conditions of 23 ℃ and a peel speed of 300 mm/min is preferably 0.06N/20mm or more, more preferably 0.1N/20mm or more, and still more preferably 0.15N/20mm or more, as described above. This configuration is suitable for ensuring the adhesion between the adhesive layer 12 of the dicing tape 10 after curing and the adhesive layer 20 thereon, and therefore, when the expansion step is performed after curing of the adhesive layer 12 in the case of using the dicing die-bonding film X, it is preferable to suppress the occurrence of partial peeling, i.e., floating, of the semiconductor chip with the adhesive layer from the adhesive layer 12 in this step. The peel force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 after radiation curing in the T-peel test at 23 ℃ and a peel speed of 300 mm/min is preferably 0.25N/20mm or less, more preferably 0.23N/20mm or less, and still more preferably 0.2N/20mm or less, as described above. This configuration is suitable for achieving good pickup of the semiconductor chip with the adhesive layer from the adhesive layer 12 after curing in the pickup step performed after curing of the adhesive layer 12. In the T-peel test at 23 ℃ and a peel speed of 300 mm/min, the peel force between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 before radiation curing is preferably 2N/20mm or more, as described above. This configuration is suitable for securing adhesion between the adhesive layer 12 in an uncured state in the dicing tape 10 and the adhesive layer 20 thereon, and therefore, in the case where the adhesive layer 12 is subjected to a spreading step in an uncured state when the dicing die-bonding film X is used, it is suitable for suppressing generation of partial peeling, that is, floating, of the semiconductor chip with the adhesive layer from the adhesive layer 12 in this step.

The difference between the arithmetic average surface roughness (Ra) of the adhesive surface 12a of the adhesive layer 12 and the surface 20b of the adhesive layer 20, which are used to form the interface between the adhesive layer 12 and the adhesive layer 20 in the dicing die-bonding film X, is preferably 100nm or less, as described above. This configuration is suitable for ensuring adhesion between the adhesive layer 12 and the adhesive layer 20 thereon, and is therefore suitable for suppressing the occurrence of partial peeling, i.e., floating, of the semiconductor chip with the adhesive layer from the adhesive layer 12 in the spreading step.

As described above, the pressure-sensitive adhesive layer 12 in the dicing die-bonding film X preferably contains an acrylic polymer including the 1 st unit derived from an alkyl (meth) acrylate having an alkyl group with 10 or more carbon atoms and the 2 nd unit derived from 2-hydroxyethyl (meth) acrylate. This configuration is suitable for achieving high shear adhesion between the pressure-sensitive adhesive layer 12 and the adhesive layer 20 thereon, and therefore, is suitable for appropriately applying a cutting force to the adhesive layer 20 on the dicing tape 10 spread in the in-plane direction in the spreading step to cut the adhesive layer 20.

The molar ratio of the 1 st unit to the 2 nd unit in the acrylic polymer in the pressure-sensitive adhesive layer 12 is preferably 1 or more, more preferably 3 or more, and still more preferably 5 or more, as described above. This configuration is preferable in terms of ensuring the high shear adhesion between the pressure-sensitive adhesive layer 12 and the pressure-sensitive adhesive layer 20 thereon and suppressing the adhesive interaction between the two layers in the stacking direction, and thus contributes to achieving good pickup in the pickup step. As described above, the molar ratio is preferably 40 or less, more preferably 35 or less, and still more preferably 30 or less. This configuration is preferable in that adhesion between the adhesive layer 12 and the adhesive layer 20 is ensured, and generation of partial peeling, that is, floating, of the semiconductor chip with the adhesive layer from the adhesive layer 12 is suppressed in the spreading step.

The acrylic polymer in the pressure-sensitive adhesive layer 12 is preferably an addition product of an unsaturated functional group-containing isocyanate compound added as a radiation polymerizable component, as described above. When the acrylic polymer in the pressure-sensitive adhesive layer 12 is such an unsaturated functional group-containing isocyanate compound adduct, the molar ratio of the unsaturated functional group-containing isocyanate compound to the 2 nd unit derived from 2-hydroxyethyl (meth) acrylate in the acrylic polymer is preferably 0.1 or more, more preferably 0.2 or more, and further preferably 0.3 or more. These configurations are suitable for appropriately increasing the elasticity of the pressure-sensitive adhesive layer 12 through the reaction between the acrylic polymer and the unsaturated functional group-containing isocyanate compound, and contribute to good cleavage of the pressure-sensitive adhesive layer 20 in the spreading step. In the reaction composition containing the unsaturated functional group-containing isocyanate compound and the acrylic polymer for forming an addition product obtained by adding the unsaturated functional group-containing isocyanate compound to the acrylic polymer, the molar ratio of the unsaturated functional group-containing isocyanate compound to the unit derived from 2-hydroxyethyl (meth) acrylate (unit 2) in the acrylic polymer is preferably 2 or less, more preferably 1.5 or less, and still more preferably 1.3 or less, as described above, from the viewpoint of reducing low molecular weight components in the cured pressure-sensitive adhesive layer 12.

Fig. 4 to 9 show a method for manufacturing a semiconductor device according to an embodiment of the present invention.

In the present semiconductor device manufacturing method, first, as shown in fig. 4 a and 4 b, the dividing grooves 30a are formed in the semiconductor wafer W (dividing groove forming step). The semiconductor wafer W has a 1 st surface Wa and a2 nd surface Wb. Various semiconductor elements (not shown) are already mounted on the 1 st surface Wa of the semiconductor wafer W, and wiring structures and the like (not shown) necessary for the semiconductor elements are already formed on the 1 st surface Wa. In this step, after the wafer processing tape T1 having the adhesive surface T1a is bonded to the 2 nd surface Wb of the semiconductor wafer W, the dividing groove 30a having a predetermined depth is formed on the 1 st surface Wa of the semiconductor wafer W by using a rotary blade such as a dicing device while the semiconductor wafer W is held on the wafer processing tape T1. The dividing grooves 30a are gaps for separating the semiconductor wafer W into semiconductor chip units (the dividing grooves 30a are schematically shown by thick lines in fig. 4 to 6).

Next, as shown in fig. 4 (c), the wafer processing tape T2 having the adhesive surface T2a is attached to the 1 st surface Wa side of the semiconductor wafer W, and the wafer processing tape T1 is peeled from the semiconductor wafer W.

Next, as shown in fig. 4 d, the semiconductor wafer W is thinned to a predetermined thickness by grinding from the 2 nd surface Wb while the semiconductor wafer W is held on the wafer processing tape T2 (wafer thinning step). The grinding process can be performed using a grinding apparatus provided with a grinding wheel. Through this wafer thinning step, the semiconductor wafer 30A that can be singulated into a plurality of semiconductor chips 31 is formed in the present embodiment. Specifically, the semiconductor wafer 30A has a portion (connection portion) connected to a portion which is to be singulated into the plurality of semiconductor chips 31 on the 2 nd surface Wb side. The thickness of the connecting portion of the semiconductor wafer 30A, i.e., the distance between the 2 nd surface Wb of the semiconductor wafer 30A and the tip of the dividing groove 30A on the 2 nd surface Wb side is, for example, 1 to 30 μm, preferably 3 to 20 μm.

Next, as shown in fig. 5 (a), the semiconductor wafer 30A held by the wafer processing tape T2 is bonded to the adhesive layer 20 of the dicing die-bonding film X. Thereafter, as shown in fig. 5 (b), the wafer processing tape T2 is peeled off from the semiconductor wafer 30A. When the pressure-sensitive adhesive layer 12 in the dicing die-bonding film X is a radiation-curable pressure-sensitive adhesive layer, the pressure-sensitive adhesive layer 12 may be irradiated with radiation such as ultraviolet rays from the base material 11 side after the bonding of the semiconductor wafer 30A to the adhesive layer 20, instead of the radiation irradiation described above in the production process of the dicing die-bonding film X. The irradiation amount is, for example, 50 to 500mJ/cm²Preferably 100 to 300mJ/cm². The region of the dicing die-bonding film X to be irradiated as a measure for reducing the adhesive strength of the adhesive layer 12 (irradiation region R shown in fig. 1) is, for example, a region other than the peripheral edge portion of the bonding region of the adhesive layer 20 in the adhesive layer 12.

Next, after the ring frame 41 is attached to the adhesive layer 20 in the dicing die-bonding film X, the dicing die-bonding film X with the semiconductor wafer 30A is fixed to the holding tool 42 of the expanding device as shown in fig. 6 (a).

Then, as shown in fig. 6 (b), the 1 st expanding step (cooling expanding step) under relatively low temperature conditions is performed to singulate the semiconductor wafer 30A into a plurality of semiconductor chips 31 and also to cut the adhesive layer 20 of the dicing die bonding film X into small adhesive layers 21, thereby obtaining the adhesive layer-attached semiconductor chips 31. In this step, the hollow cylindrical jacking member 43 provided in the expanding device is brought into contact with the dicing tape 10 and raised on the lower side of the dicing die-bonding film X in the drawing, and expands the dicing tape 10 to which the dicing die-bonding film X of the semiconductor wafer 30A is bonded so as to extend along the two-dimensional direction including the radial direction and the circumferential direction of the semiconductor wafer 30A. The expansion is performed under conditions such that a tensile stress in the range of 15 to 32MPa, preferably 20 to 32MPa is generated in the dicing tape 10. The temperature condition in the cooling expansion step is, for example, 0 ℃ or lower, preferably-20 to-5 ℃, more preferably-15 to-5 ℃, and still more preferably-15 ℃. The spreading speed (speed of raising the jack-up member 43) in the cooling spreading step is preferably 0.1 to 100 mm/sec. In addition, the expansion amount in the cooling expansion step is preferably 3 to 16 mm.

In this step, the semiconductor wafer 30A is cut at a thin portion which is easily broken, and is singulated into the semiconductor chips 31. At the same time, in this step, the adhesive layer 20 adhering to the adhesive layer 12 of the spread dicing tape 10 is suppressed from deforming in each region where each semiconductor chip 31 adheres, while such a deformation suppressing action is not generated at a position facing the dividing groove between the semiconductor chips 31, and in such a state, the tensile stress generated in the dicing tape 10 acts. As a result, the adhesive layer 20 is cut at a position facing the dividing groove between the semiconductor chips 31. After this step, as shown in fig. 6 (c), the raising member 43 is lowered to release the spread state of the dicing tape 10.

Next, as shown in fig. 7 (a), a2 nd expanding step is performed under relatively high temperature conditions to widen the distance (spacing distance) between the semiconductor chips 31 with the adhesive layer. In this step, the hollow cylindrical jacking member 43 provided in the expanding device is raised again to expand the dicing tape 10 for dicing the die-bonding film X. The temperature in the second expansion step 2 is, for example, 10 ℃ or higher, preferably 15 to 30 ℃. The expanding speed (the speed at which the jack-up member 43 ascends) in the second expanding step 2 is, for example, 0.1 to 10 mm/sec, preferably 0.3 to 1 mm/sec. The expansion amount in the 2 nd expansion step is, for example, 3 to 16 mm. In this step, the distance between the semiconductor chips 31 with the adhesive layer is increased to such an extent that the semiconductor chips 31 with the adhesive layer can be picked up from the dicing tape 10 in a pickup step described later. After this step, the jack-up member 43 is lowered as shown in fig. 7 (b), and the expanded state of the dicing tape 10 is released. In order to suppress the reduction in the distance between the semiconductor chips 31 with the adhesive layer on the dicing tape 10 after the expanded state is released, it is preferable to heat and shrink the outer portion of the semiconductor chip 31 holding region of the dicing tape 10 before the expanded state is released.

Next, after a cleaning step of cleaning the semiconductor chip 31 side of the dicing tape 10 having the semiconductor chip 31 with the adhesive layer by using a cleaning liquid such as water as necessary, as shown in fig. 8, the semiconductor chip 31 with the adhesive layer is picked up from the dicing tape 10 (pickup step). For example, the semiconductor chip 31 with the adhesive layer as the pickup object is lifted up via the dicing tape 10 by raising the needle member 44 of the pickup mechanism at the lower side of the dicing tape 10 in the drawing, and then sucked and held by the suction jig 45. In the picking-up step, the needle member 44 is pushed up at a speed of, for example, 1 to 100 mm/sec and the needle member 44 is pushed up at a height of, for example, 50 to 3000 μm.

Then, as shown in fig. 9 (a), the picked-up semiconductor chip 31 with the adhesive layer is temporarily fixed to a predetermined adherend 51 via the adhesive layer 21. Examples of the adherend 51 include: a lead frame, a TAB (Tape Automated Bonding) film, a wiring substrate, and a separately manufactured semiconductor chip. The shear adhesion strength at 25 ℃ of the adhesive layer 21 at the time of temporary fixing is preferably 0.2MPa or more, more preferably 0.2 to 10MPa, to the adherend 51. The configuration in which the shear adhesion of the adhesive layer 21 is 0.2MPa or more is suitable for suppressing shear deformation from occurring in the adhesive surface between the adhesive layer 21 and the semiconductor chip 31 or the adherend 51 due to ultrasonic vibration or heating in the wire bonding step described later, and for performing wire bonding appropriately. The shear adhesion strength of the adhesive layer 21 at 175 ℃ during temporary fixation is preferably 0.01MPa or more, and more preferably 0.01 to 5MPa, with respect to the adherend 51.

Then, as shown in fig. 9 b, the electrode pad (not shown) of the semiconductor chip 31 and the terminal portion (not shown) of the adherend 51 are electrically connected by the bonding wire 52 (wire bonding step). The connection of the electrode pad of the semiconductor chip 31, the terminal portion of the adherend 51, and the bonding wire 52 can be achieved by ultrasonic welding with heating, and is performed so that the adhesive layer 21 is not thermally cured. As the bonding wire 52, for example, a gold wire, an aluminum wire, or a copper wire can be used. The heating temperature of the wire in the wire bonding is, for example, 80 to 250 ℃, preferably 80 to 220 ℃. The heating time is several seconds to several minutes.

Then, as shown in fig. 9 c, the semiconductor chip 31 is sealed with a sealing resin 53 for protecting the semiconductor chip 31 and the bonding wire 52 on the adherend 51 (sealing step). In this step, thermosetting of the adhesive layer 21 is performed. In this step, the sealing resin 53 is formed by, for example, a transfer molding technique using a mold. As a constituent material of the sealing resin 53, for example, an epoxy resin can be used. In this step, the heating temperature for forming the sealing resin 53 is, for example, 165 to 185 ℃, and the heating time is, for example, 60 seconds to several minutes. If the sealing resin 53 is not sufficiently cured in this step (sealing step), a post-curing step for completely curing the sealing resin 53 is performed after this step. Even when the adhesive layer 21 is not completely heat-cured in the sealing step, the adhesive layer 21 may be completely heat-cured together with the sealing resin 53 in the post-curing step. In the post-curing step, the heating temperature is, for example, 165 to 185 ℃, and the heating time is, for example, 0.5 to 8 hours.

In the above operation, a semiconductor device can be manufactured.

In the present embodiment, as described above, after the semiconductor chip 31 with the adhesive layer is temporarily fixed to the adherend 51, the wire bonding step is performed in a state where the adhesive layer 21 has not been completely thermally cured. Instead of this configuration, in the present invention, after the semiconductor chip 31 with the adhesive layer is temporarily fixed to the adherend 51, the adhesive layer 21 may be thermally cured and then the wire bonding step may be performed.

In the method for manufacturing a semiconductor device according to the present invention, the wafer thinning step shown in fig. 10 may be performed instead of the wafer thinning step described above with reference to fig. 4 (d). After the above-described process with reference to fig. 4 (c), in the wafer thinning step shown in fig. 10, in a state where the semiconductor wafer W is held on the wafer processing tape T2, the wafer is thinned to a predetermined thickness by grinding from the 2 nd surface Wb, and the semiconductor wafer segment 30B including the plurality of semiconductor chips 31 and held on the wafer processing tape T2 is formed. In this step, a method of grinding the wafer until the dividing groove 30a itself is exposed on the 2 nd surface Wb side (the 1 st method) may be adopted, or the following method may be adopted: the wafer is ground from the 2 nd surface Wb side to just before the dividing groove 30a, and then a pressing force of the rotary grindstone against the wafer is applied to crack between the dividing groove 30a and the 2 nd surface Wb, thereby forming a semiconductor wafer divided body 30B (method 2). The depth of the dividing groove 30a formed as described above with reference to fig. 4 (a) and 4 (b) from the 1 st surface Wa is determined as appropriate according to the method used. Fig. 10 schematically shows the dividing groove 30a formed by the method 1 or the dividing groove 30a formed by the method 2 and the crack connected thereto by a thick line. In the present invention, the semiconductor wafer divided body 30B fabricated as described above may be bonded to the dicing die bonding film X in place of the semiconductor wafer 30A, and the above-described steps may be performed with reference to fig. 5 to 9.

Fig. 11 (a) and 11 (B) show the 1 st expanding step (cooling expanding step) performed after the semiconductor wafer divided body 30B is bonded to the dicing die-bonding film X. In this step, the hollow cylindrical jacking member 43 provided in the expanding device is brought into contact with the dicing tape 10 on the lower side of the dicing die-bonding film X in the drawing and is raised, so that the dicing tape 10 to which the dicing die-bonding film X of the semiconductor wafer segment 30B is bonded is expanded so as to be stretched in the two-dimensional direction including the radial direction and the circumferential direction of the semiconductor wafer segment 30B. The expansion is performed under conditions that a tensile stress in the range of, for example, 1 to 100MPa, preferably 5 to 40MPa is generated in the dicing tape 10. The temperature conditions in this step are, for example, 0 ℃ or lower, preferably-20 to-5 ℃, more preferably-15 to-5 ℃, and still more preferably-15 ℃. The expanding speed (speed of raising the jack-up member 43) in this step is preferably 1 to 500 mm/sec. The amount of expansion in this step is preferably 50 to 200 mm. By such a cooling and spreading step, the adhesive layer 20 of the dicing die-bonding film X is cut into small adhesive layers 21, and the semiconductor chip 31 with an adhesive layer is obtained. Specifically, in this step, the adhesive layer 20 that adheres to the adhesive layer 12 of the expanded dicing tape 10 is inhibited from deforming in each region where the semiconductor chips 31 of the semiconductor wafer divided body 30B adhere to each other, while such a deformation inhibiting effect is not generated at a position facing the dividing groove 30a between the semiconductor chips 31, and the tensile stress generated in the dicing tape 10 in this state acts. As a result, the adhesive layer 20 is cut at a position facing the dividing groove 30a between the semiconductor chips 31.

In the method for manufacturing a semiconductor device of the present invention, instead of the above-described structure in which the semiconductor wafer 30A or the semiconductor wafer divided body 30B is bonded to the dicing die-bonding film X, the semiconductor wafer 30C produced in the following manner may be bonded to the dicing die-bonding film X.

As shown in fig. 12 (a) and 12 (b), first, the modified region 30b is formed in the semiconductor wafer W. The semiconductor wafer W has a 1 st surface Wa and a2 nd surface Wb. Various semiconductor elements (not shown) are already mounted on the 1 st surface Wa side of the semiconductor wafer W, and wiring structures and the like (not shown) necessary for the semiconductor elements are already formed on the 1 st surface Wa. In this step, after the wafer processing tape T3 having the adhesive surface T3a is bonded to the 1 st surface Wa side of the semiconductor wafer W, the semiconductor wafer W is irradiated with laser light having a light-converging point located inside the wafer from the opposite side to the wafer processing tape T3 along the pre-dividing line thereof in a state where the semiconductor wafer W is held on the wafer processing tape T3, and the modified region 30b is formed in the semiconductor wafer W by ablation due to multiphoton absorption. The modified region 30b is a weakened region for separating the semiconductor wafer W into semiconductor chip units. A method of forming the modified regions 30b on the preliminary dividing lines in the semiconductor wafer by laser irradiation is described in detail in, for example, japanese patent application laid-open No. 2002-192370, and the laser irradiation conditions in this embodiment can be appropriately adjusted within the following ranges, for example.

< laser irradiation Condition >

(A) Laser

(B) Lens for condensing light

Multiplying power of 100 times or less

NA 0.55

Transmittance to laser wavelength of 100% or less

(C) The moving speed of the mounting table for mounting the semiconductor substrate is below 280 mm/s

Next, as shown in fig. 12C, the semiconductor wafer W is thinned to a predetermined thickness by grinding from the 2 nd surface Wb while the semiconductor wafer W is held on the wafer processing tape T3, thereby forming a semiconductor wafer 30C which can be singulated into a plurality of semiconductor chips 31 (wafer thinning step). In the present invention, the semiconductor wafer 30C produced as described above may be bonded to the dicing die-bonding film X in place of the semiconductor wafer 30A, and the above-described steps may be performed with reference to fig. 5 to 9.

Fig. 13 (a) and 13 (b) show the 1 st expanding step (cooling expanding step) performed after the semiconductor wafer 30C is bonded to the dicing die-bonding film X. In this step, the hollow cylindrical jacking member 43 provided in the expanding device is brought into contact with the dicing tape 10 on the lower side of the dicing die-bonding film X in the drawing and is raised, and the dicing tape 10 of the dicing die-bonding film X to which the semiconductor wafer 30C is bonded is expanded so as to be stretched in the two-dimensional direction including the radial direction and the circumferential direction of the semiconductor wafer 30C. The expansion is performed under conditions such that a tensile stress in the range of, for example, 1 to 100MPa, preferably 5 to 40MPa is generated in the dicing tape 10. The temperature conditions in this step are, for example, 0 ℃ or lower, preferably-20 to-5 ℃, more preferably-15 to-5 ℃, and still more preferably-15 ℃. The expanding speed (speed of raising the jack-up member 43) in this step is preferably 1 to 500 mm/sec. The amount of expansion in this step is preferably 50 to 200 mm. By such a cooling and spreading step, the adhesive layer 20 of the dicing die-bonding film X is cut into small adhesive layers 21, and the semiconductor chip 31 with an adhesive layer is obtained. Specifically, in this step, cracks are formed in the fragile modified region 30b of the semiconductor wafer 30C, and the semiconductor wafer is singulated into the semiconductor chips 31. At the same time, in this step, the adhesive layer 20 in close contact with the adhesive layer 12 of the expanded dicing tape 10 is inhibited from being deformed in each region in which the semiconductor chips 31 of the semiconductor wafer 30C are in close contact with each other, while such a deformation inhibiting action is not generated at a position facing the crack formation position of the wafer, and the tensile stress generated in the dicing tape 10 in this state acts. As a result, the adhesive layer 20 is cut at a position facing the crack formation position between the semiconductor chips 31.

In the present invention, the dicing die-bonding film X can be used to obtain a semiconductor chip with an adhesive layer as described above, and can also be used to obtain a semiconductor chip with an adhesive layer when a plurality of semiconductor chips are stacked and mounted in 3-dimensional fashion. The semiconductor chips 31 mounted in 3-dimensional manner may or may not be provided with a spacer interposed therebetween together with the adhesive layer 21.

Examples

[ example 1 ]

Adhesive layer

Mixing acrylic polymerA₁(copolymer of ethyl acrylate, butyl acrylate, acrylonitrile and glycidyl methacrylate, weight average molecular weight 120 ten thousand, glass transition temperature 0 ℃, epoxy value 0.4eq/kg)54 parts by mass, solid phenolic resin (trade name "MEHC-7851 SS", solid at 23 ℃, manufactured by Michelia Kogyo Co., Ltd.) 3 parts by mass, liquid phenolic resin (trade name "MEH-8000H", liquid at 23 ℃, manufactured by Michelia Kogyo Co., Ltd.) 3 parts by mass, and silica filler (trade name "SO-C2", average particle diameter 0.5 μm, manufactured by Admatech) 40 parts by mass were added to methyl ethyl ketone and mixed, and the concentration was adjusted SO that the viscosity at room temperature was 700 mPas, to obtain adhesive composition C₁. Next, an adhesive composition C was applied to the silicone release-treated surface of the PET spacer (thickness: 38 μm) having the silicone release-treated surface using an applicator₁A coating film was formed, and the coating film was dried by heating at 130 ℃ for 2 minutes. In the above operation, an adhesive layer of 10 μm thickness of example 1 was formed on the PET separator. The composition of the adhesive layer of example 1 is shown in table 1 (in table 1, the units of the respective numerical values representing the composition of the composition are relative "parts by mass" in the composition except for the numerical values relating to MOI described later).

Adhesive layer

In a reaction vessel equipped with a condenser tube, a nitrogen inlet tube, a thermometer and a stirring device, a mixture comprising 100 parts by mole of Lauryl Acrylate (LA), 20 parts by mole of 2-hydroxyethyl acrylate (2HEA), 0.2 parts by mass of benzoyl peroxide as a polymerization initiator per 100 parts by mass of these monomer components, and toluene as a polymerization solvent was stirred (polymerization reaction) at 60 ℃ for 10 hours under a nitrogen atmosphere. Thus, an acrylic polymer P was obtained₁The polymer solution of (1). For the acrylic polymer P in the polymer solution₁The weight average molecular weight (Mw) was 46 ten thousand, the glass transition temperature was 9.5 ℃ and the molar ratio of the unit derived from LA to the unit derived from 2HEA was 5. Then, the acrylic acid-containing polymer P is contained₁2-methacryloyloxyethyl isocyanate (MOI)) The mixture with dibutyltin dilaurate as an addition reaction catalyst was stirred at room temperature under an air atmosphere for 48 hours (addition reaction). In the reaction solution, the amount of MOI added was 20 parts by mole based on 100 parts by mole of the lauryl acrylate, and the amount of MOI added was based on the acrylic polymer P₁The molar ratio of the total amount of units derived from 2HEA and/or their hydroxyl groups in (a) is 1. Further, in the reaction solution, the compounding amount of dibutyltin dilaurate to the acrylic polymer P₁100 parts by mass is 0.01 part by mass. By this addition reaction, an acrylic polymer P containing a methacrylate group in the side chain is obtained₂(acrylic polymer to which unsaturated functional group-containing isocyanate compound is added). Next, the acrylic polymer P was added to the polymer solution₂100 parts by mass of a polyisocyanate compound (trade name "Coronate L", manufactured by tokyo co) and 2 parts by mass of a photopolymerization initiator (trade name "Irgacure 127", manufactured by BASF) were mixed, and the mixture was diluted with toluene so that the viscosity of the mixture at room temperature was 500mPa · s to obtain an adhesive composition C₂. Then, on the adhesive layer formed on the PET separator, adhesive composition C was applied using an applicator₂A coating film was formed, and the coating film was dried by heating at 130 ℃ for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 10 μm on the adhesive layer. Then, a substrate (trade name "RB-0104", thickness 130 μm, manufactured by Kabushiki Kaisha) made of ethylene-vinyl acetate copolymer (EVA) was laminated on the exposed surface of the pressure-sensitive adhesive layer at room temperature using a laminator. Next, punching is performed so that the processing blade enters from the EVA base material side until reaching the separator. Thus, a cut die bond film having a disc shape with a diameter of 370mm, which had a laminated structure of EVA base material, adhesive layer and adhesive layer, was formed on the separator. In the above manner, a dicing die-bonding film of example 1 having a laminated structure including a dicing tape (EVA base material/adhesive layer) and an adhesive layer was produced.

[ examples 2 to 4 ]

The dicing die-bonding films of examples 2 to 4 were produced in the same manner as the dicing die-bonding film of example 1 except that the amount of MOI added was changed from 20 parts by mole to 16 parts by mole (example 2), 12 parts by mole (example 3), or 8 parts by mole (example 4) in the formation of the pressure-sensitive adhesive layer.

[ example 5 ]

Adhesive layer

Mixing acrylic polymer A₂18 parts by mass of a nitrile group-containing acrylic copolymer (trade name: Teisanrein SG-70L, product name: 90 ten thousand, glass transition temperature: 13 ℃ C., acid value: 5mgKOH/g, manufactured by Nagase ChemteX Corporation), 6 parts by mass of a solid epoxy resin (trade name: KI-3000, solid at 23 ℃ C., manufactured by Nippon Tekko Kaisha) 5 parts by mass of a liquid epoxy resin (trade name: YL-980, liquid at 23 ℃ C., manufactured by Mitsubishi chemical Co., Ltd.) and 40 parts by mass of a silica filler (trade name: SO-C2, average particle diameter: 0.5 μm, manufactured by Admatec Corporation) were added to methyl ethyl ketone and mixed, and the concentration was adjusted SO that the viscosity at room temperature was 700 mPas, to obtain an adhesive composition C₃. Then, an adhesive composition C was applied to the silicone release-treated surface of the PET spacer (thickness: 38 μm) having the silicone release-treated surface using an applicator₃A coating film was formed, and the coating film was dried by heating at 130 ℃ for 2 minutes. In the above operation, an adhesive layer of 10 μm thickness of example 5 was formed on the PET separator.

Adhesive layer

The pressure-sensitive adhesive layer of example 5 was formed in the same manner as the pressure-sensitive adhesive layer of example 1 except that the blending amount of the MOI was changed from 20 parts by mole to 16 parts by mole, and the dicing die-bonding film of example 5 was produced.

[ example 6 ]

In a reaction vessel equipped with a condenser, a nitrogen inlet tube, a thermometer and a stirring device, 100 parts by mass of 2-ethylhexyl acrylate (2EHA) and 20 parts by mass of 2-hydroxyethyl acrylate (2HEA) were added under a nitrogen atmosphere at 60 ℃ to a reaction mixture containing 100 parts by mass of these monomer componentsThe mixture of benzoyl peroxide as a polymerization initiator and toluene as a polymerization solvent was stirred for 10 hours (polymerization reaction). Thus, an acrylic polymer P was obtained₃The polymer solution of (1). For the acrylic polymer P in the polymer solution₃The weight average molecular weight (Mw) was 40 ten thousand, and the glass transition temperature was 60 ℃. Then, the acrylic polymer P is added₃A mixture of the polymer solution of (a), 2-methacryloyloxyethyl isocyanate (MOI), and dibutyltin dilaurate as an addition reaction catalyst was stirred at room temperature under an air atmosphere for 48 hours (addition reaction). In this reaction solution, the amount of MOI added was 16 parts by mole with respect to 100 parts by mole of the above-mentioned 2-ethylhexyl acrylate. Further, in the reaction solution, the compounding amount of dibutyltin dilaurate to the acrylic polymer P₃100 parts by mass is 0.01 part by mass. By this addition reaction, an acrylic polymer P containing a methacrylate group in the side chain is obtained₄The polymer solution of (1). Thereafter, to the polymer solution was added a solution corresponding to the acrylic polymer P₄100 parts by mass of a polyisocyanate compound (trade name "Coronate L", manufactured by tokyo co) and 2 parts by mass of a photopolymerization initiator (trade name "Irgacure 127", manufactured by BASF) were mixed, and the mixture was diluted with toluene so that the viscosity of the mixture at room temperature was 500mPa · s to obtain an adhesive composition C₄. In the adhesive composition C₃When the pressure-sensitive adhesive layer was formed on the adhesive layer formed, the pressure-sensitive adhesive composition C was used₄Except for this, a dicing die-bonding film of example 6 was produced in the same manner as the dicing die-bonding film of example 5.

[ comparative example 1 ]

In the formation of the pressure-sensitive adhesive layer, the pressure-sensitive adhesive composition C described above is replaced₂Using the above adhesive composition C₄Except for this, a dicing die-bonding film of comparative example 1 was produced in the same manner as the dicing die-bonding film of example 1.

[ comparative example 2 ]

With fruitThe same as in example 1, from the above adhesive composition C₁An adhesive layer (thickness 10 μm) was formed on the PET spacer. The adhesive layer was punched out to have a diameter of 370mm in a state with the separator. On the other hand, the pressure-sensitive adhesive composition C was applied to a silicone release-treated surface of a PET separator (thickness: 38 μm) having a silicone release-treated surface by using an applicator₄A coating film was formed, and the coating film was dried by heating at 130 ℃ for 2 minutes to form a pressure-sensitive adhesive layer having a thickness of 10 μm on a PET separator. Then, a substrate (trade name "RB-0104", thickness 130 μm, manufactured by Kabushiki Kaisha) made of ethylene-vinyl acetate copolymer (EVA) was laminated on the exposed surface of the pressure-sensitive adhesive layer at room temperature using a laminator. The laminated sheet thus obtained was punched out to a diameter of 370mm with a separator, to form a dicing tape. Next, the dicing tape and the adhesive layer thus obtained were aligned and bonded so that the center of the dicing tape and the center of the adhesive layer were aligned. In the above manner, the dicing die-bonding film of comparative example 2 having a laminated structure including the dicing tape (EVA base material/adhesive layer) and the adhesive layer was produced.

Surface free energy

The surface free energy of the pressure-sensitive adhesive layer-side surface of the adhesive layer and the surface free energy of the pressure-sensitive adhesive layer-side surface of the ultraviolet-cured adhesive layer were determined for each of the dicing die-bonding films of examples 1 to 6 and comparative examples 1 and 2. Specifically, first, ultraviolet light is irradiated from the dicing tape base material side to the dicing tape adhesive layer of the dicing die-bonding film, and the adhesive layer is ultraviolet-cured. In the ultraviolet irradiation, a high-pressure mercury lamp was used so that the cumulative amount of light irradiated was 350mJ/cm². Next, the adhesive layer is peeled from the dicing tape and/or the adhesive layer thereof, and the surface to be surface free energy determination (the adhesive layer-side surface of the adhesive layer and the adhesive layer-side surface of the adhesive layer) is exposed. Then, water (H) brought into contact with the surface free energy determination object side was treated at 20 ℃ and a relative humidity of 65%₂O) and diiodomethane (CH)₂I₂) The contact angle of each droplet was measured using a contact angle meter. Then, the user can use the device to perform the operation,using the values of the contact angle θ w of water and the contact angle θ i of methylene iodide, γ s was determined by the method described in Journal of Applied Polymer Science, vol.13, p1741-1747(1969)^d(Dispersion force component of surface free energy) and γ s^h(hydrogen bonding force component of surface free energy). And, converting γ s^dAnd γ s^hThe added value γ s (═ γ s)^d+γs^h) As the surface free energy of the object plane. Gamma s for identifying object surface for each surface free energy^dAnd γ s^hThe expression is obtained as a solution of the 2-dimensional simultaneous equations of the following expressions (1) and (2). In the formulas (1) and (2), γ w represents the surface free energy of water, γ w^dThe dispersive force component, γ w, being the surface free energy of water^hHydrogen bonding force component which is the surface free energy of water, gamma i is the surface free energy of methyl iodide, gamma i^dIs the dispersive power component of the surface free energy of methyl iodide,. gamma.i^hFor the hydrogen bonding force component of the surface free energy of methyl iodide, γ w ═ 72.8mJ/m, which is a known literature value, was used²、γw^d＝21.8mJ/m²、γw^h＝51.0mJ/m²、γi＝50.8mJ/m²、γi^d＝48.5mJ/m²、γi^h＝2.3mJ/m². The surface free energy γ s of the pressure-sensitive adhesive layer side surface of the pressure-sensitive adhesive layer thus obtained₁(mJ/m²) And surface free energy γ s of the adhesive layer-side surface of the adhesive layer after ultraviolet curing_{2 (a) to (b)}mJ/m²) Shown in table 1. The difference | γ s of these surface free energies₁-γs₂|(mJ/m²) Also shown in table 1.

Mathematical formula 1

Surface roughness

Each of the dicing die-bonding methods of examples 1 to 6 and comparative examples 1 and 2The film was examined for the surface roughness of the pressure-sensitive adhesive layer-side surface of the pressure-sensitive adhesive layer and the surface roughness of the pressure-sensitive adhesive layer-side surface of the pressure-sensitive adhesive layer. Specifically, first, the pressure-sensitive adhesive layer of the dicing tape in the dicing die-bonding film is irradiated with ultraviolet rays from the dicing tape base material side, and the pressure-sensitive adhesive layer is cured by ultraviolet rays. In the ultraviolet irradiation, a high-pressure mercury lamp was used, and the cumulative quantity of light irradiated was set to 350mJ/cm². The adhesive layer is then peeled from the dicing tape and/or the adhesive layer thereof. Next, the arithmetic mean surface roughness was determined for the adhesive layer surface and the adhesive layer surface exposed by the peeling using a confocal laser microscope (trade name "opterlics H300", manufactured by Lasertec Corporation). The surface roughness Ra of the adhesive layer side surface of the adhesive layer₁(nm), surface roughness Ra2 (nm) of the adhesive layer side surface of the adhesive layer, and difference | Ra of these surface roughness₁-Ra₂The results are shown in Table 1.

180 DEG peel adhesion of adhesive layer

The adhesive layer in each of the dicing die-bonding films of examples 1 to 6 and comparative examples 1 and 2 was examined for 180 ° peel adhesion at 23 ℃. First, the adhesive layer in the dicing tape was irradiated with ultraviolet rays from the substrate side. In the ultraviolet irradiation, a high-pressure mercury lamp was used, and the cumulative quantity of light irradiated was set to 350mJ/cm². Then, a laminate (width 10mm × length 100mm) having a laminate structure of the dicing tape base material, the adhesive layer, and the adhesive layer was cut out from the dicing die-bonding film. Then, the adhesive layer side of the laminate was bonded to a silicon wafer by a pressure bonding operation in which a 2kg roller was reciprocated 1 time at 60 ℃, and thereafter, the bonded body was left at 60 ℃ for 2 minutes. Then, the adhesive layer and the base material were peeled from the adhesive layer on the silicon wafer. Next, a liner tape (product name "BT-315", manufactured by ritonan electric corporation) was attached to the adhesive layer remaining on the silicon wafer, and the adhesive layer was peeled off from the silicon wafer, so that the adhesive layer was transferred from the silicon wafer to the liner tape. In this manner, adhesive layer test pieces (width 10 mm. times. length 100mm) with a backing tape were prepared. Bonding an adhesive layer sample sheet to a SUS plate as an adherendThe adhesive layer sample sheet was pressure-bonded to the adherend by a pressure-bonding operation in which a 2kg roller was reciprocated 1 time. Then, after leaving at room temperature for 30 minutes, the 180 ℃ peel adhesion (N/10nm) of the pressure-sensitive adhesive layer sample sheet to the SUS plate was measured using a tensile tester (trade name "Autograph AGS-J", manufactured by Shimadzu corporation). In this measurement, the measurement temperature and/or the peeling temperature was 23 ℃, the stretching angle and/or the peeling angle was 180 °, and the stretching speed was 10 mm/min. The measurement results are shown in table 1.

Tensile storage modulus of adhesive layer

The tensile storage modulus (MPa) at 23 ℃ was determined for each adhesive layer of examples 1 to 6 and comparative examples 1 and 2 based on dynamic viscoelasticity measurement using a dynamic viscoelasticity measuring apparatus (trade name "Rheogel-E4000", manufactured by UBM). A sample sheet to be subjected to dynamic viscoelasticity measurement was prepared by forming a laminate in which each adhesive layer was laminated to a thickness of 80 μm, and then cutting the laminate in a size of 4mm in width × 20mm in length. In this measurement, the initial inter-jig distance of the sample piece holding jig was set to 10mm, the measurement mode was set to the tensile mode, the measurement temperature range was-30 ℃ to 100 ℃, the frequency was set to 10Hz, the dynamic strain was set to. + -. 0.5 μm, and the temperature increase rate was set to 5 ℃/min. The measurement results are shown in table 1.

T-shaped peeling test

The dicing die-bonding films of examples 1 to 6 and comparative examples 1 and 2 were each examined for the peeling force between the pressure-sensitive adhesive layer and the adhesive layer in the following manner. First, a test piece with an adhesive layer in an uncured state was prepared from each dicing die-bonding film. Specifically, a backing tape (trade name "BT-315", manufactured by ritonao electric corporation) was attached to the adhesive layer side of the dicing die-bonding film, and a test piece having a width of 50mm × a length of 120mm was cut from the dicing die-bonding film with the backing tape. Then, the test piece was subjected to a T-peel test using a tensile tester (trade name "Autograph AGS-J", manufactured by Shimadzu corporation) to measure a peel force (N/20 mm). In this measurement, the temperature conditions were set at 23 ℃,The peeling speed was set to 300 mm/min. On the other hand, a test piece in which the adhesive layer was cured was also prepared from each dicing die-bonding film. Specifically, for dicing die-bonding film, the adhesive layer was irradiated from the substrate side with 350mJ/cm²After curing the adhesive layer with ultraviolet rays, a backing tape (product name "BT-315", manufactured by ritonao electric corporation) was attached to the adhesive layer side of the dicing die-bonding film, and a test piece having a width of 50mm × a length of 120mm was cut from the dicing die-bonding film with the backing tape. Then, the test piece was subjected to a T-peel test using a tensile tester (trade name "Autograph AGS-J", manufactured by Shimadzu corporation) to measure a peel force (N/20 mm). In this measurement, the temperature condition was set to 23 ℃ and the peeling speed was set to 300 mm/min. The measurement results in the T-peel test are shown in table 1.

Implementation of expansion process and pickup process

Using the dicing die-bonding films of examples 1 to 6 and comparative examples 1 and 2, the following bonding step, 1 st expanding step for cleaving (cooling expanding step), 2 nd expanding step for separating (room temperature expanding step), and pickup step were performed.

In the bonding step, the semiconductor wafer divided body held by a wafer processing tape (trade name "UB-3083", manufactured by ritonan electric corporation) was bonded to the adhesive layer of the dicing die bonding film, and then the wafer processing tape was peeled off from the semiconductor wafer divided body. In the dicing die-bonding film, the adhesive layer of the dicing tape is irradiated with ultraviolet rays from the base material side to cure the adhesive layer with ultraviolet rays in advance. In the ultraviolet irradiation, a high-pressure mercury lamp was used, and the cumulative quantity of light irradiated was set to 350mJ/cm². In the bonding, a laminator was used, and the bonding speed was 10 mm/sec, the temperature condition was 60 ℃ and the pressure condition was 0.15 MPa. Further, the semiconductor wafer division bodies are formed and prepared as follows. First, a bare wafer (12 inches in diameter) having both surfaces mirror-finished with a ring frame held on a wafer processing tape (trade name "V-12S", manufactured by Nindon electric Co., Ltd.) was subjected to a mirror finishing process780 μm thick, manufactured by Tokyo chemical Co., Ltd.), and a dividing groove (25 μm in width, 50 μm in depth, 10mm × 10mm in subdivision) for singulation was formed from one surface side thereof by a rotary knife (manufactured by DISCO Corporation, manufactured by NBC-ZH 203O SE HCBB) using a dicing apparatus (manufactured by DISCO Corporation). Then, a wafer processing tape (trade name "UB-3083", manufactured by Nindon electric corporation) was bonded to the dividing groove forming surface, and then the wafer processing tape (trade name "V-12S") was peeled off from the wafer. Then, grinding was performed from the other surface (surface on which the dividing grooves were not formed) side of the wafer using a back grinding apparatus (trade name "DGP 8760", manufactured by DISCO Corporation), thereby thinning the wafer to a thickness of 25 μm. The semiconductor wafer division bodies (in a state of being held by the wafer processing tape) are formed in accordance with the above operations. The semiconductor wafer division body includes a plurality of semiconductor chips (10mm × 10 mm).

The cooling expansion process was performed by a cooling expansion unit using a Die Separator (trade name "Die Separator DDS 2300", manufactured by DISCO Corporation). Specifically, first, an SUS ring frame (manufactured by DISCO Corporation) having a diameter of 12 inches was attached to an annular frame attaching region (the periphery of a work attaching region) of the adhesive layer in the dicing die bonding film having the semiconductor wafer divided body at room temperature. Then, the dicing die-bonding film is set in an apparatus, and a dicing tape of the dicing die-bonding film with the semiconductor wafer divided bodies is expanded by a cooling expansion unit of the apparatus. In the cooling expansion step, the temperature was-15 ℃, the expansion rate was 100 mm/sec, and the expansion amount was 7 mm.

The room temperature expansion step was performed by a room temperature expansion unit using a Die Separator (trade name "Die Separator DDS 2300", manufactured by DISCO Corporation). Specifically, the dicing tape with the dicing die-bonding film of the semiconductor wafer divided body having undergone the cooling and expanding step is expanded by the normal temperature expanding means of the apparatus. In the normal-temperature expansion step, the temperature was 23 ℃, the expansion rate was 1 mm/sec, and the expansion amount was 10 mm. Then, the dicing die-bonding film expanded at normal temperature is subjected to heat shrinking treatment. The treatment temperature was 200 ℃ and the treatment time was 20 seconds.

In the pickup step, an apparatus having a pickup mechanism (trade name "Die binder SPA-300", manufactured by seikagawa) was used to try to pick up the semiconductor chips with the adhesive layer which have been singulated on the dicing tape. For this pickup, the needle-like member was pushed up at a speed of 1 mm/sec, the amount of pushing up was 2000 μm, and the pickup evaluation number was 5.

In the above-described process using each of the dicing die-bonding films of examples 1 to 6 and comparative examples 1 and 2, regarding the cooling and spreading step, the floating evaluation at the time of cleaving was excellent (. circleincircle.) when the floating of the singulated semiconductor chip with the adhesive layer from the dicing tape did not occur, and the floating evaluation at the time of cleaving was poor (x) when the floating area of the singulated semiconductor chip with the adhesive layer (i.e., the local peeling of the adhesive layer from the dicing tape adhesive layer in the singulated semiconductor chip with the adhesive layer) was 40% or more with respect to the total area of the singulated semiconductor chips. In the pickup step, a case where all five semiconductor chips with an adhesive layer were able to be picked up from the dicing tape was evaluated as excellent pickup property (. circleincircle.), a case where the number of semiconductor chips with an adhesive layer able to be picked up from the dicing tape was 1 to 4 was evaluated as good pickup property (. largecircle.), and a case where all 1 semiconductor chips with an adhesive layer were unable to be picked up from the dicing tape was evaluated as poor pickup property (. largecircle.). The evaluation results are shown in table 1.

[ evaluation ]

With the dicing die-bonding films of examples 1 to 6, the adhesive layer-attached semiconductor chip does not float off the dicing tape in the cooling and spreading step, the adhesive layer can be favorably cut, and the adhesive layer-attached semiconductor chip can be favorably picked up in the pickup step.

TABLE 1

Claims

1. A dicing die-bonding film comprising:

a dicing tape having a laminated structure including a substrate and an adhesive layer; and

an adhesive layer that releasably adheres to the adhesive layer in the dicing tape,

the adhesive agent layer is a radiation curing adhesive agent layer,

the adhesive layer and the adhesive layer can form an interface between the adhesive layer and the adhesive layer, and the adhesive layer can form a thickness of 3.5-9 mJ/m²Is poor.

2. The dicing die-bonding film according to claim 1, wherein the surface of the adhesive layer may have 32mJ/m²The following surface free energy.

3. The dicing die-bonding film according to claim 1, wherein the surface free energy of the surface of the adhesive layer is 30 to 45mJ/m²。

4. The dicing die-bonding film according to claim 1, wherein the adhesive layer exhibits a 180 ° peel adhesion of 0.1 to 20N/10mm to a SUS plane in a peel test under conditions of 23 ℃, a peel angle of 180 ° and a stretching speed of 10 mm/min.

5. The dicing die-bonding film according to claim 1, wherein the tensile storage modulus at 23 ℃ of the adhesive layer measured under conditions of an initial inter-jig distance of 10mm, a frequency of 10Hz, a dynamic strain. + -. 0.5 μm, and a temperature rise rate of 5 ℃/min for an adhesive layer sample sheet having a width of 4mm and a thickness of 80 μm is 100 to 4000 MPa.

6. The dicing die-bonding film according to claim 1, wherein the pressure-sensitive adhesive layer has a peeling force between the pressure-sensitive adhesive layer and the adhesive layer before radiation curing of 2N/20mm or more in a T-peel test at 23 ℃ and a peeling speed of 300 mm/min.

7. The dicing die-bonding film according to claim 1, wherein a difference between an arithmetic average surface roughness of the surface of the adhesive layer and an arithmetic average surface roughness of the surface of the adhesive layer is 100nm or less.

8. The dicing die-bonding film according to claim 1, wherein the adhesive layer contains an acrylic polymer containing: a 1 st unit derived from an alkyl (meth) acrylate having an alkyl group with 10 or more carbon atoms and a2 nd unit derived from 2-hydroxyethyl (meth) acrylate.

9. The dicing die-bonding film according to claim 8, wherein the molar ratio of the 1 st unit to the 2 nd unit in the acrylic polymer is 1 to 40.

10. The dicing die-bonding film according to claim 8, wherein the acrylic polymer is an addition product of an isocyanate compound containing an unsaturated functional group.

11. The dicing die-bonding film according to claim 10, wherein a molar ratio of the unsaturated functional group-containing isocyanate compound to the 2 nd unit in the acrylic polymer is 0.1 or more.

12. The dicing die-bonding film according to any one of claims 1 to 11, wherein the pressure-sensitive adhesive layer has a peeling force between the pressure-sensitive adhesive layer and the adhesive layer after radiation curing of 0.06 to 0.25N/20mm in a T-peel test at 23 ℃ and a peeling speed of 300 mm/min.

13. The dicing die-bonding film according to claim 12, wherein an outer peripheral end of the adhesive layer is located at a distance of 1000 μm or less from an outer peripheral end of the adhesive layer in a film in-plane direction.

14. The dicing die-bonding film according to any one of claims 1 to 11, wherein an outer peripheral end of the adhesive layer is located at a distance of 1000 μm or less from an outer peripheral end of the adhesive layer in a film in-plane direction.