JP7381315B2 - Adhesive film with dicing tape - Google Patents

Description

The present invention relates to an adhesive film with a dicing tape. More specifically, the present invention relates to an adhesive film with a dicing tape that can be used in the manufacturing process of semiconductor devices.

In the manufacturing process of a semiconductor device, an adhesive film with a dicing tape is sometimes used in the process of obtaining a semiconductor chip having an adhesive film of a size equivalent to the chip, that is, a semiconductor chip with an adhesive film. The adhesive film with dicing tape has a size corresponding to the semiconductor wafer to be processed, and includes, for example, a dicing tape consisting of a base material and an adhesive layer, and an adhesive film that is releasably attached to the adhesive layer side. and has. The adhesive film has a disk shape that is larger than the semiconductor wafer that is the workpiece, and is concentrically bonded to the adhesive layer side of a dicing tape that has a disk shape that is larger than the adhesive film. .

As one method for obtaining a semiconductor chip with an adhesive film using an adhesive film with a dicing tape, there is a known method in which the adhesive film with a dicing tape undergoes a step of expanding the dicing tape and cleaving the adhesive film. . In this method, first, a semiconductor wafer is bonded onto an adhesive film of an adhesive film with a dicing tape. For example, this semiconductor wafer is processed so that it can be later cut together with an adhesive film and separated into multiple semiconductor chips, and it is processed so that it can be cut into a predetermined size after being pasted. may be done.

Next, in order to break the adhesive film on the dicing tape, the dicing tape of the adhesive film with the dicing tape is stretched in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer using an expanding device. In this expanding step, the semiconductor wafer on the adhesive film is also broken at locations corresponding to the breaking locations in the adhesive film, and the semiconductor wafer is diced into a plurality of semiconductor chips on the adhesive film or dicing tape.

Next, in order to widen the distance between the plurality of semiconductor chips with adhesive films after cutting on the dicing tape, an expanding process is performed again. Next, for example, after a cleaning step, each semiconductor chip, together with an adhesive film of a size equivalent to the chip that is in close contact with it, is pushed up from below the dicing tape by a pin member of a pickup mechanism and picked up from above the dicing tape. In this way, a semiconductor chip with an adhesive film is obtained. If this adhesive film is a die bonding film, it will be fixed to an adherend such as a mounting board through the adhesive film by die bonding. Also, if the adhesive film is a back-adhesion film, the electrode side opposite to the back-adhesion film will be mounted on the mounting board, etc.

Techniques regarding the adhesive film with dicing tape used as described above are described, for example, in Patent Documents 1 to 3 below.

Japanese Patent Application Publication No. 2007-2173 Japanese Patent Application Publication No. 2010-177401 Japanese Patent Application Publication No. 2016-115804

In recent years, semiconductor wafers have been made easy to divide at the planned dividing lines by irradiating laser light onto the planned dividing lines to form modified regions, and then the semiconductor wafers have been made into adhesive films with dicing tapes. After pasting or pasting the semiconductor wafer to an adhesive film with dicing tape, the above-mentioned modified region is formed on the semiconductor wafer, and then the dicing tape is expanded (hereinafter referred to as "expand") at a low temperature (for example, -25 to 0°C). A method of obtaining individual semiconductor chips (semiconductor chips with adhesive films) by cutting the semiconductor wafer and the adhesive film together has been proposed. This is a method called stealth dicing (registered trademark).

In order to properly cut the metal layer constituting the circuit surface of the semiconductor wafer on which the modified region is formed or the adhesive film in the adhesive film with dicing tape by cool expansion, it is necessary to perform the expansion at low temperature and high speed. In particular, when the metal layer is thick, it is required to increase the expansion speed under low temperature conditions. However, when a semiconductor wafer is bonded to the adhesive film using a conventional adhesive film with dicing tape and expanded at a low temperature and high speed, the edge of the semiconductor wafer or the edge of the semiconductor chip after cutting may be damaged. There was a problem that the dicing tape in the adhesive film with dicing tape would tear in the area where the dicing tape was applied.

The present invention has been made in view of the above problems, and its object is to provide an adhesive film with a dicing tape that is less prone to tearing even when cool expanded at low temperatures and high speeds.

As a result of intensive studies to achieve the above object, the present inventors have discovered a dicing tape having a laminated structure including a base material and an adhesive layer, and a dicing tape that adheres removably to the adhesive layer of the dicing tape. an adhesive film, the adhesive film has a peeling force of 5 N/10 mm or more in a peel test against silicon at a temperature of 25°C and a peeling angle of 180°, and the amount of fracture push-up measured by a specific fracture push-up test. It has been found that when an adhesive film with a dicing tape having a diameter of 10 mm or more is used, the dicing tape is less likely to tear even when cool expanding is performed at a low temperature and high speed. The present invention was completed based on these findings.

A first embodiment of the present invention includes a dicing tape having a laminated structure including a base material and an adhesive layer, and an adhesive film that is releasably adhered to the adhesive layer of the dicing tape,
The adhesive film has a peel force of 5 N/10 mm or more in a peel test against silicon at a temperature of 25° C. and a peel angle of 180°,
Provided is an adhesive film with a dicing tape having a breaking push-up amount of 10 mm or more as measured by the breaking push-up test described below.
Breaking push-up test: A 500-μm-thick silicon disk is pasted onto an adhesive film, and an expanding device is used to push up a hollow cylindrical member with the silicon disk at a temperature of -15°C and a speed of 400 mm/s. In the area outside the area, the adhesive film with dicing tape is brought into contact with the dicing tape side and raised, and the dicing tape is expanded so as to be stretched in two-dimensional directions including the radial direction and the circumferential direction. Then, the amount of rise of the push-up member when the dicing tape breaks is measured as the break-up push-up amount.

The adhesive film with dicing tape includes a dicing tape and an adhesive film. The dicing tape has a laminated structure including a base material and an adhesive layer. The adhesive film is releasably adhered to the adhesive layer of the dicing tape. An adhesive film with a dicing tape having such a configuration can be used to obtain a semiconductor chip with an adhesive film in the process of manufacturing a semiconductor device.

As described above, the adhesive film with a dicing tape has a peeling force of 5 N/10 mm or more in a peeling test against silicon of the adhesive film at a temperature of 25° C. and a peeling angle of 180°. Since the above-mentioned peeling force at a temperature of 25° C. is 5 N/10 mm or more, the semiconductor wafer is difficult to peel off from the adhesive film when cool expanding is performed at low temperature and high speed.

Further, as described above, the amount of breakage thrust measured by a breakage pushup test under the conditions of a temperature of -15° C. and a speed of 400 mm/s is 10 mm or more. That is, under conditions of a temperature of -15° C. and a speed of 400 mm/s, the dicing tape does not break even when pushed up by 10 mm. Adhesive film with dicing tape generally stretches easily and has high breaking strength when a semiconductor wafer is not attached, but when a semiconductor wafer is attached to the adhesive film, the adhesive film with dicing tape The area where the semiconductor wafer is attached is difficult to expand, and when cool expansion is performed at low temperature and high speed, the edge of the semiconductor wafer (the boundary between the area where the semiconductor wafer is attached and the area outside of the area), The dicing tape tends to tear easily in the region corresponding to the edge of the semiconductor chip obtained by cutting. On the other hand, the above-mentioned adhesive film with dicing tape has the above-mentioned breaking push-up amount of 10 mm or more at a temperature of -15°C or lower, so that when cool expanding is performed at low temperature and high speed, the area where the semiconductor wafer is attached is Even if the elongation of the adhesive film with the dicing tape is limited, the dicing tape is less likely to tear. Therefore, when the adhesive film with a dicing tape is cool-expanded at low temperature and high speed, the semiconductor wafer is difficult to peel off from the adhesive film, and the dicing tape is difficult to tear.

Preferably, the base material includes a polyurethane base material. The adhesive film with dicing tape having such a configuration has high flexibility, and when cool expanded at low temperature and high speed, the expansion of the adhesive film with dicing tape is limited in the area where the semiconductor wafer is attached, for example. Even if stress is locally concentrated in a region corresponding to the edge of a semiconductor wafer or the edge of a semiconductor chip, the dicing tape is less likely to tear.

The adhesive layer is preferably a radiation-curable acrylic adhesive layer, and has a glass transition temperature of −20° C. or lower. An adhesive film with a dicing tape having such a structure has good adhesion to the adhesive film even in a low-temperature environment, and chips with an adhesive film are less likely to peel off during cool expansion at low temperatures and high speeds. Even during subsequent water washing, the adhesive film exposed outside the semiconductor wafer can be prevented from scattering.

It is preferable that the total thickness of the base material and the adhesive layer is 80 μm or more. The adhesive film with a dicing tape having such a configuration has a sufficiently thick dicing tape, and can further suppress tearing of the dicing tape.

The base material preferably has a multilayer structure including a polyurethane base material. Although the above-mentioned effects can be obtained by using a polyurethane base material, blocking tends to occur when the adhesive film with dicing tape is laminated or wound to form a wound body. Therefore, by forming the adhesive film with a dicing tape having such a structure into a multilayer structure including a polyurethane base material, blocking can be made less likely to occur while obtaining the effect of including the polyurethane base material.

In the adhesive film with a dicing tape according to the present invention, the dicing tape is less likely to tear even when cool expanded at a low temperature and high speed. Therefore, by using the adhesive film with dicing tape described above, the metal layer constituting the circuit surface of the semiconductor wafer in which the modified region is formed, and the adhesive film in the adhesive film with dicing tape can be effectively cut by cool expansion. I can do it. Furthermore, even if the metal layer is particularly thick, it can be cut well by cool expansion.

FIG. 1 is a schematic diagram (front sectional view) showing an embodiment of an adhesive film with a dicing tape. It is a schematic diagram (front sectional view) showing other embodiments of an adhesive film with a dicing tape. FIG. 2 is a schematic diagram (front sectional view) showing an embodiment of a dividing groove forming step and a wafer thinning step. FIG. 2 is a schematic diagram (front sectional view) showing an embodiment of a process of bonding a workpiece to an adhesive film with a dicing tape. It is a schematic diagram (front sectional view) showing one embodiment of a 1st expansion process. It is a schematic diagram (front sectional view) showing one embodiment of a 2nd expansion process. It is a schematic diagram (front sectional view) showing one embodiment of a pick-up process. It is a schematic diagram (front sectional view) showing one embodiment of a temporary fixing process, a wire bonding process, and a sealing process. FIG. 7 is a schematic diagram (front sectional view) showing another embodiment of the wafer thinning process. It is a schematic diagram (front sectional view) showing other embodiments of a 1st expansion process. FIG. 2 is a schematic diagram (front sectional view) showing an embodiment of a process of forming a modified region and a process of thinning a wafer. It is a schematic diagram (front sectional view) showing still other embodiment of a 1st expansion process.

[Adhesive film with dicing tape]
An adhesive film with a dicing tape according to an embodiment of the present invention includes a dicing tape having a laminated structure including a base material and an adhesive layer, and an adhesive film that is releasably adhered to the adhesive layer of the dicing tape. and. An embodiment of the adhesive film with dicing tape will be described below.

FIG. 1 is a schematic cross-sectional view showing one embodiment of the adhesive film with a dicing tape. As shown in FIG. 1, the adhesive film with dicing tape 1 includes a dicing tape 10 and an adhesive film 20 laminated on the adhesive layer 12 of the dicing tape 10. It can be used in the expansion process in the process of obtaining.

The adhesive film with a dicing tape has a disk shape with a size corresponding to a semiconductor wafer to be processed in the process of manufacturing a semiconductor device. The diameter of the adhesive film in the adhesive film with dicing tape is, for example, within the range of 305 to 335 mm (compatible with 12-inch wafers).

The adhesive film has a peel force of 5 N/10 mm or more against silicon in a peel test at a temperature of 25° C. and a peel angle of 180°. Since the above-mentioned peeling force at a temperature of 25° C. is 5 N/10 mm or more, the semiconductor wafer is difficult to peel off from the adhesive film when cool expanding is performed at low temperature and high speed. The above peeling force is preferably 8 N/mm or more. The peeling force may be, for example, 50 N/mm or less, or 20 N/mm or less.

The above-mentioned peeling force can be measured using a tensile tester (trade name "Autograph AG-X", manufactured by Shimadzu Corporation). Specifically, the method for preparing the test piece used for the measurement and the measurement method are as follows.

A 6-inch silicon wafer was placed on a hot plate heated to 70°C with the mirror side facing up, and the adhesive film surface of the adhesive film with dicing tape was attached to the mirror side of the silicon wafer for testing. Get a piece. This bonding is performed by pressing a 2 kg hand roller back and forth once. After leaving it for 2 minutes, the test piece was removed from the hot plate and left until it returned to room temperature. Then, using a tensile tester, it was tested at 25°C, a peel angle of 180°, and a tensile speed of 300 mm/min. A peel test is performed on the test piece at the interface between the adhesive film and the silicon wafer, and the average value of the values in the range starting from 10 mm and ending at 100 mm from the start of measurement is obtained as the peel force of the adhesive film to the silicon.

The above-mentioned adhesive film with dicing tape has a breaking push-up amount measured by the following breaking push-up test of 10 mm or more, preferably 15 mm or more, and more preferably 20 mm or more.

Breaking push-up test: A 500-μm-thick silicon disk is pasted onto an adhesive film, and an expanding device is used to push up a hollow cylindrical member with the silicon disk at a temperature of -15°C and a speed of 400 mm/s. In the area outside the area, the adhesive film with dicing tape is brought into contact with the dicing tape side and raised, and the dicing tape is expanded so as to be stretched in two-dimensional directions including the radial direction and the circumferential direction. Then, the amount of rise of the push-up member when the dicing tape breaks is measured as the break-up push-up amount.

The above-mentioned fracture thrust amount is the fracture thrust amount measured by a fracture thrust test under the conditions of a temperature of -15° C. and a speed of 400 mm/s, and is 10 mm or more. That is, under conditions of a temperature of -15° C. and a speed of 400 mm/s, the dicing tape does not break even when pushed up by 10 mm. Adhesive film with dicing tape generally stretches easily and has high breaking strength when a semiconductor wafer is not attached, but when a semiconductor wafer is attached to the adhesive film, the adhesive film with dicing tape The area where the semiconductor wafer is attached is difficult to expand, and when cool expansion is performed at low temperature and high speed, the edge of the semiconductor wafer (the boundary between the area where the semiconductor wafer is attached and the area outside of the area), The dicing tape tends to tear easily in the region corresponding to the edge of the semiconductor chip obtained by cutting. On the other hand, the adhesive film with a dicing tape according to an embodiment of the present invention has the above-mentioned breakage thrust amount of 10 mm or more at a temperature of -15°C or lower, so that when cool expanding is performed at a low temperature and high speed, the semiconductor wafer Even if the elongation of the adhesive film with dicing tape is restricted in the area where it is attached, the dicing tape is less likely to tear. Therefore, when the adhesive film with a dicing tape is cool-expanded at low temperature and high speed, the semiconductor wafer is difficult to peel off from the adhesive film, and the dicing tape is difficult to tear.

The dicing tape 10 in the adhesive film with dicing tape 1 has a laminated structure including a base material 11 and an adhesive layer 12.

(Base material)
The base material in a dicing tape is an element that functions as a support in a dicing tape or an adhesive film with a dicing tape. Examples of the base material include plastic base materials (especially plastic films). The base material may be a single layer or a laminate of base materials of the same type or different types.

Examples of the resin constituting the plastic base material include low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymerized polypropylene, block copolymerized polypropylene, homopolypropylene, Polybutene, polymethylpentene, ethylene-vinyl acetate copolymer (EVA), ionomer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid ester (random, alternating) copolymer, ethylene-butene Polyolefin resins such as copolymers and ethylene-hexene copolymers; polyurethanes; polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, and polybutylene terephthalate (PBT); polycarbonates; polyimides; polyether ether ketones; polyether imides; Examples include polyamides such as aramid and wholly aromatic polyamide; polyphenylsulfide; fluororesin; polyvinyl chloride; polyvinylidene chloride; cellulose resin; and silicone resin.

Among others, the base material preferably contains polyurethane as a main component. That is, the base material preferably includes a polyurethane base material. The adhesive film with dicing tape having such a configuration has high flexibility, and when cool expanded at low temperature and high speed, the expansion of the adhesive film with dicing tape is limited in the area where the semiconductor wafer is attached, for example. Even if stress is locally concentrated in a region corresponding to the edge of a semiconductor wafer or the edge of a semiconductor chip, the dicing tape is less likely to tear.

Note that the main component of the base material is the component that occupies the largest mass proportion among the constituent components. The above resins may be used alone or in combination of two or more. When the adhesive layer is a radiation-curable adhesive layer as described below, the base material preferably has radiation transparency.

Examples of the polyurethane include resins obtained by reacting a polyisocyanate compound and a polyol compound (ie, a copolymer of a polyisocyanate compound and a polyol compound).

Examples of the polyisocyanate compound include one or a mixture of two or more of known aromatic, aliphatic, and alicyclic diisocyanates. Examples of the diisocyanates include tolylene diisocyanate, 4,4-diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, 1,5-naphthalene diisocyanate, and isophorone diisocyanate. Further, trifunctional or higher functional polyisocyanates or polyisocyanate adducts may be mixed with the above diisocyanates as needed.

Examples of the polyol compounds include ethylene glycol, diethylene glycol, 1,3-propanediol, propylene glycol (1,2-propanediol), butanediol (1,3-butanediol, 1,4-butanediol, etc.), 1, Low molecular weight glycols such as 6-hexanediol and cyclohexanedimethanol; polyether diols such as polyethylene glycol, polypropylene glycol, polytetramethylene glycol, and polytetramethylene glycol-polycaprolactone copolymer; propylene glycol,
Polyester diol obtained from diols such as butanediol and hexanediol and dibasic acids such as adipic acid, sebacic acid, azelaic acid, isophthalic acid, terephthalic acid, and fumaric acid; polycaprolactone diol, polyvalerolactone diol, lactone block Known diols such as lactone diols such as copolymerized diols can be used. Further, if necessary, the above diols and a trifunctional or higher functional polyol compound (such as a polyether polyol or a polyester polyol) may be mixed and used.

The base material preferably has a multilayer structure including a polyurethane base material. Although the above-mentioned effects can be obtained by using a polyurethane base material, blocking tends to occur when the adhesive film with dicing tape is laminated or wound to form a wound body. Therefore, by forming a multilayer structure including a polyurethane base material, it is possible to obtain the effect of including the polyurethane base material while making blocking less likely to occur.

In the base material having the multilayer structure, examples of the base material other than the polyurethane base material include those exemplified and explained as the above-mentioned plastic base material. Among the resins constituting the base material other than the above-mentioned polyurethane base material, polyolefin resins are preferred from the viewpoint of having performance suitable for cool expansion and better blocking prevention properties, such as polyethylene, linear low-density polyethylene, etc. , polyethylene such as medium-density polyethylene, high-density polyethylene, and ultra-low-density polyethylene; polypropylene such as random copolymerized polypropylene, block copolymerized polypropylene, and homopolypropylene; ethylene-vinyl acetate copolymer (EVA); and ionomers are more preferred.

When the base material has a multilayer structure including a polyurethane base material, the ratio of the thickness of the polyurethane base material to the total thickness of the base material is preferably 50% or more, more preferably 60% or more. , more preferably 70% or more. When the above ratio is 50% or more, the stretchability of the polyurethane base material can be fully exhibited. The above ratio is, for example, 95% or less, preferably 90% or less, more preferably 80% or less.

When the base material has a multilayer structure including a polyurethane base material, the multilayer structure may be a two-layer structure or a three-layer structure. In the multilayer structure described above, from the viewpoint of further suppressing blocking, it is preferable that the layer in the base material farthest from the adhesive layer is a layer (base material) containing a polyolefin resin as a main component.

When the base material is a plastic film, the plastic film may be non-oriented or may be oriented in at least one direction (uniaxial direction, biaxial direction, etc.). When oriented in at least one direction, the plastic film can be heat-shrinkable in the at least one direction. If the dicing tape has heat-shrinkable properties, it becomes possible to heat-shrink the outer periphery of the semiconductor wafer, thereby fixing the diced semiconductor chips with adhesive films with a wide gap between them. Therefore, the semiconductor chip can be easily picked up. In order for the base material and the dicing tape to have isotropic heat shrinkability, the base material is preferably a biaxially oriented film. The plastic film oriented in at least one direction can be obtained by stretching (uniaxial stretching, biaxial stretching, etc.) an unstretched plastic film in at least one direction.

The base material and the dicing tape preferably have a heat shrinkage rate of 1 to 30%, more preferably 2 to 25%, and more preferably 2 to 25% in a heat treatment test conducted at a heating temperature of 100 ° C. and a heating time of 60 seconds. Preferably it is 3 to 20%, particularly preferably 5 to 20%. The heat shrinkage rate is preferably a heat shrinkage rate in at least one direction of the MD direction and the TD direction.

The surface of the base material on the side of the adhesive layer is subjected to treatments such as corona discharge treatment, plasma treatment, sand mat treatment, ozone exposure treatment, flame exposure treatment, and high-voltage electric shock treatment in order to improve adhesion and retention with the adhesive layer. Physical treatments such as exposure treatment and ionizing radiation treatment; chemical treatments such as chromic acid treatment; surface treatments such as adhesion-facilitating treatment using a coating agent (undercoat). Further, in order to impart antistatic ability, a conductive vapor deposition layer containing a metal, an alloy, an oxide thereof, or the like may be provided on the surface of the base material. The surface treatment for improving adhesion is preferably applied to the entire surface of the base material on the pressure-sensitive adhesive layer side.

When the adhesive film is a back adhesive film described below, the arithmetic mean surface roughness Ra of the base material is preferably 100 nm or less. When the Ra is 100 nm or less, light scattering is suppressed and the laser transmittance for laser marking is further improved. In particular, it is preferable that the arithmetic mean surface roughness Ra on the side where the adhesive layer is not provided is 100 nm or less. Generally, to prevent blocking, a base material with an arithmetic mean surface roughness Ra of 100 nm or more on one side is sometimes used; By setting the above surface as the pressure-sensitive adhesive layer side and filling the concave portions of the rough surface with the pressure-sensitive adhesive layer, light scattering can be suppressed and laser transmittance for laser marking can be improved.

The thickness of the base material is preferably 40 μm or more, more preferably 50 μm or more, and even more preferably 55 μm from the viewpoint of ensuring the strength for the base material to function as a support in a dicing tape and an adhesive film with a dicing tape. The thickness is particularly preferably 60 μm or more. Moreover, from the viewpoint of realizing appropriate flexibility in the dicing tape and the adhesive film with the dicing tape, the thickness of the base material is preferably 200 μm or less, more preferably 180 μm or less, and still more preferably 150 μm or less.

(Adhesive layer)
The adhesive layer in the adhesive film with dicing tape is preferably an adhesive layer containing an acrylic polymer as a base polymer (acrylic adhesive layer). The above-mentioned acrylic polymer is a polymer containing, as a polymer structural unit, a structural unit derived from an acrylic monomer (a monomer component having a (meth)acryloyl group in the molecule).

It is preferable that the acrylic polymer is a polymer containing the largest amount of structural units derived from (meth)acrylic acid ester in mass proportion. In addition, only one type of acrylic polymer may be used, or two or more types may be used. Furthermore, in this specification, "(meth)acrylic" refers to "acrylic" and/or "methacrylic" (either or both of "acrylic" and "methacrylic"), and the same applies to the others. .

Examples of the above (meth)acrylic esters include hydrocarbon group-containing (meth)acrylic esters that may have an alkoxy group. Examples of the hydrocarbon group-containing (meth)acrylic ester include (meth)acrylic acid alkyl ester, (meth)acrylic acid cycloalkyl ester, (meth)acrylic acid aryl ester, and the like.

Examples of the (meth)acrylic acid alkyl ester include methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, s-butyl ester, t-butyl ester, pentyl ester, Isopentyl ester, hexyl ester, heptyl ester, octyl ester, 2-ethylhexyl ester, isooctyl ester, nonyl ester, decyl ester, isodecyl ester, undecyl ester, dodecyl ester (lauryl ester), tridecyl ester, tetradecyl ester , hexadecyl ester, octadecyl ester, eicosyl ester, etc.

Examples of the above-mentioned (meth)acrylic acid cycloalkyl ester include cyclopentyl ester and cyclohexyl ester of (meth)acrylic acid. Examples of the above-mentioned (meth)acrylic acid aryl ester include phenyl ester and benzyl ester of (meth)acrylic acid.

Examples of the hydrocarbon group-containing (meth)acrylic ester having an alkoxy group include those in which one or more hydrogen atoms in the hydrocarbon group in the above hydrocarbon group-containing (meth)acrylic ester are substituted with an alkoxy group, Examples include 2-methoxymethyl ester, 2-methoxyethyl ester, and 2-methoxybutyl ester of (meth)acrylic acid.

The hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group may be used alone or in combination of two or more.

The above-mentioned hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group has a total number of carbon atoms in the ester moiety (if it has an alkoxy group, the total number including the number of carbon atoms in the alkoxy group) from 6 to 10. It is preferable that there be. Particularly preferred is a hydrocarbon group-containing (meth)acrylic ester in which the total number of carbon atoms in the hydrocarbon groups is 6 to 10. In these cases, it is possible to more easily achieve both suppression of lifting between the pressure-sensitive adhesive layer and the adhesive film in the expanding process and thereafter, and good pick-up properties in the pick-up process.

In order to properly exhibit basic properties such as tackiness due to the hydrocarbon group-containing (meth)acrylic ester which may have an alkoxy group in the adhesive layer, all monomer components for forming the acrylic polymer must be used. The proportion of the hydrocarbon group-containing (meth)acrylic acid ester which may have an alkoxy group in is preferably 20 mol% or more, more preferably 30 mol% or more, still more preferably 40 mol% or more.

In this specification, the above-mentioned monomer component includes a compound having a radiation-polymerizable group (for example, a second functional group described below and a radiation-polymerizable Compounds with a carbon-carbon double bond) are not included.

The above acrylic polymer is derived from other monomer components that can be copolymerized with the above hydrocarbon group-containing (meth)acrylic acid ester that may have an alkoxy group for the purpose of modifying cohesive force, heat resistance, etc. It may also include structural units. Examples of the other monomer components include polar groups such as carboxy group-containing monomers, acid anhydride monomers, hydroxy group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, and nitrogen atom-containing monomers. Examples include containing monomers.

Examples of the carboxy 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, itaconic anhydride, and the like. Examples of the hydroxy group-containing monomer include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, Examples include 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, methylglycidyl (meth)acrylate, and the like.

Examples of the sulfonic acid group-containing monomers include styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, sulfopropyl (meth)acrylate, and (meth)acrylamidopropanesulfonic acid. ) Acryloyloxynaphthalene sulfonic acid and the like.

Examples of the phosphoric acid group-containing monomer include 2-hydroxyethyl acryloyl phosphate.

Examples of the nitrogen atom-containing monomer include morpholino group-containing monomers such as (meth)acryloylmorpholine, cyano group-containing monomers such as (meth)acrylonitrile, and amide group-containing monomers such as (meth)acrylamide.

The above-mentioned other monomer components may be used alone or in combination of two or more.

In order to properly exhibit basic properties such as tackiness due to the hydrocarbon group-containing (meth)acrylic ester which may have an alkoxy group in the adhesive layer, all monomer components for forming the acrylic polymer must be used. The total proportion of the polar group-containing monomers in is preferably 60 mol% or less, more preferably 50 mol% or less. Further, the total proportion of the polar group-containing monomers is preferably 10 mol% or more, more preferably 15 mol% or more.

In order to properly exhibit basic properties such as tackiness due to the hydrocarbon group-containing (meth)acrylic ester which may have an alkoxy group in the adhesive layer, all monomer components for forming the acrylic polymer must be used. The proportion of the structural units derived from the hydroxy group-containing monomer in is preferably 5 mol% or more, more preferably 10 mol% or more. Further, the above ratio is, for example, 80 mol% or less, and may be 70 mol% or less, or 60 mol% or less.

The acrylic polymer may contain a structural unit derived from a polyfunctional monomer copolymerizable with the monomer component forming the acrylic polymer in order to form a crosslinked structure in the polymer skeleton. Examples of the polyfunctional monomer include hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, and pentyl glycol di(meth)acrylate. Erythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy(meth)acrylate (e.g. polyglycidyl(meth)acrylate), polyester Examples include monomers having a (meth)acryloyl group and other reactive functional groups in the molecule, such as (meth)acrylate and urethane (meth)acrylate.

The above polyfunctional monomers may be used alone or in combination of two or more. In order to properly exhibit basic properties such as tackiness due to the hydrocarbon group-containing (meth)acrylic ester which may have an alkoxy group in the adhesive layer, all monomer components for forming the acrylic polymer must be used. The proportion of the polyfunctional monomer in is preferably 40 mol% or less, more preferably 30 mol% or less.

The acrylic polymer includes a structural unit derived from a monomer having a first functional group (for example, the polar group-containing monomer), a second functional group that can react with the first functional group, and a radiation-polymerizable functional group. It is preferable to have a structural part derived from a compound having When the acrylic polymer has such a configuration, it becomes easy to design the radiation-curable adhesive described below.

Combinations of the first functional group and the second functional group include, for example, a carboxy group and an epoxy group, an epoxy group and a carboxy group, a carboxyl group and an aziridyl group, an aziridyl group and a carboxy group, a hydroxy group and an isocyanate group, Examples include isocyanate groups and hydroxy groups. Among these, a combination of a hydroxy group and an isocyanate group, and a combination of an isocyanate group and a hydroxy group are preferred from the viewpoint of ease of tracking the reaction. Among these, it is technically difficult to produce a polymer having a highly reactive isocyanate group.On the other hand, from the viewpoint of ease of production and availability of an acrylic polymer having a hydroxy group, it is difficult to produce a polymer having a highly reactive isocyanate group. A combination in which the functional group is a hydroxy group and the second functional group is an isocyanate group is preferred.

In particular, the acrylic polymer has a structural unit derived from a hydroxy group-containing monomer as well as a structural part derived from a compound having a radiation-polymerizable carbon-carbon double bond (particularly a (meth)acryloyl group) and an isocyanate group. is preferred.

Examples of compounds having a radioactively polymerizable carbon-carbon double bond and an isocyanate group include methacryloyl isocyanate, 2-acryloyloxyethyl isocyanate, 2-methacryloyloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate, etc. Can be mentioned. Among these, 2-acryloyloxyethyl isocyanate and 2-methacryloyloxyethyl isocyanate are preferred. In addition, examples of acrylic polymers having hydroxy groups include those containing structural units derived from the above-mentioned hydroxy group-containing monomers and ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, and diethylene glycol monovinyl ether. can be mentioned.

The molar ratio [former/latter] of the structural unit derived from the monomer having the first functional group to the compound having the second functional group and the radiation-polymerizable functional group is preferably 0.95 or more, more preferably 1 It is .00 or more, more preferably 1.05 or more, particularly preferably 1.10 or more. When the molar ratio is 0.95 or more, the bond between the first functional group (e.g. hydroxyl group) and the second functional group (e.g. isocyanate group) is sufficiently promoted, and the acrylic polymer in the adhesive layer It is presumed that a certain amount of unreacted first functional groups remain, and the peeling force between the adhesive layer and the base material is further improved, and cracking of the adhesive layer during expansion is less likely to occur. The molar ratio may be, for example, 10.00 or less, 5.00 or less, 3.00 or less, 2.00 or less, 1.50 or less, or 1.30 or less.

In particular, the molar ratio of the hydroxy group-containing monomer to 2-methacryloyloxyethyl isocyanate [hydroxy group-containing monomer/2-methacryloyloxyethyl isocyanate] is preferably within the above range.

Acrylic polymers are obtained by subjecting one or more monomer components containing acrylic monomers to polymerization. Examples of polymerization methods include solution polymerization, emulsion polymerization, bulk polymerization, and suspension polymerization.

The adhesive layer or the adhesive forming the adhesive layer may contain a crosslinking agent. For example, when an acrylic polymer is used as the base polymer, the acrylic polymer can be crosslinked to further reduce the amount of low molecular weight substances in the adhesive layer. Moreover, the number average molecular weight of the acrylic polymer can be increased.

Examples of the crosslinking agent include polyisocyanate compounds, epoxy compounds, polyol compounds (such as polyphenol compounds), aziridine compounds, and melamine compounds. Among these, polyisocyanate compounds are preferred. When a crosslinking agent is used, the amount used is preferably about 5 parts by weight or less, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the base polymer.

The weight average molecular weight of the acrylic polymer (after crosslinking if a crosslinking agent is used) is preferably 300,000 or more (for example, 300,000 to 1,400,000), more preferably 350,000 or more. When the mass average molecular weight is 300,000 or more, the amount of low molecular weight substances in the adhesive layer tends to be small, and contamination of adhesive films, semiconductor wafers, etc. can be further suppressed.

The adhesive layer may be an adhesive layer (adhesive force-reducible type adhesive layer) whose adhesive force can be intentionally reduced by external action during the use process of the adhesive film with dicing tape. It may be an adhesive layer (adhesive force non-reducing type adhesive layer) whose adhesive strength is hardly or not reduced by external action during the process of using the adhesive film with dicing tape. It can be selected as appropriate depending on the method and conditions for singulating semiconductor wafers.

When the adhesive layer is a pressure-sensitive adhesive layer that can be reduced in adhesive strength, the adhesive layer exhibits relatively high adhesive strength and relatively low adhesive strength during the manufacturing process and usage process of the adhesive film with dicing tape. This makes it possible to use the states shown in the table. For example, when an adhesive film is attached to the adhesive layer of a dicing tape in the manufacturing process of an adhesive film with a dicing tape, or when an adhesive film with a dicing tape is used in the dicing process, the adhesive layer has a relatively high adhesive strength. While it is possible to suppress and prevent the lifting of adherends such as adhesive films from the adhesive layer by utilizing the state of In the pick-up process for picking up, the adhesive force of the adhesive layer is reduced, so that the pick-up can be easily performed.

Examples of the adhesive that forms such a pressure-sensitive adhesive layer that can reduce adhesive strength include radiation-curable adhesives, heat-foaming adhesives, and the like. As the adhesive forming the adhesive layer capable of reducing adhesive strength, one type of adhesive may be used, or two or more types of adhesive may be used.

As the radiation-curable adhesive, for example, a type of adhesive that is cured by irradiation with electron beams, ultraviolet rays, α-rays, β-rays, γ-rays, or X-rays can be used; Adhesives (ultraviolet curable adhesives) can be particularly preferably used.

The radiation-curable adhesive may contain, for example, a base polymer such as the acrylic polymer and a radiation-polymerizable monomer component or oligomer component having a radiation-polymerizable functional group such as a carbon-carbon double bond. Examples include additive-type radiation-curable adhesives.

Examples of the radiation-polymerizable monomer components include urethane (meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol monohydroxypenta( Examples include meth)acrylate, dipentaerythritol hexa(meth)acrylate, and 1,4-butanediol di(meth)acrylate.

Examples of the radiation-polymerizable oligomer component include various oligomers such as urethane-based, polyether-based, polyester-based, polycarbonate-based, and polybutadiene-based oligomers, and those having a molecular weight of about 100 to 30,000 are preferred.

The content of the radiation-curable monomer component and oligomer component in the radiation-curable adhesive forming the adhesive layer is, for example, 5 to 500 parts by mass, preferably 40 to 150 parts by mass, based on 100 parts by mass of the base polymer. It is about parts by mass.

Further, as the additive-type radiation-curable adhesive, for example, one disclosed in JP-A-60-196956 may be used.

The above-mentioned radiation-curable adhesive is an intrinsic radiation-curable adhesive containing a base polymer having a radiation-polymerizable functional group such as a carbon-carbon double bond in the polymer side chain, in the polymer main chain, or at the end of the polymer main chain. Also included are adhesives. When such an internal radiation-curable adhesive is used, it tends to be possible to suppress unintended changes in adhesive properties over time due to movement of low molecular weight components within the formed adhesive layer.

The base polymer contained in the above-mentioned internal radiation-curable adhesive is preferably an acrylic polymer. As a method for introducing a radiation-polymerizable carbon-carbon double bond into an acrylic polymer, for example, an acrylic polymer can be obtained by polymerizing (copolymerizing) a raw material monomer containing a monomer component having the first functional group. After that, the compound having the second functional group and a radiation-polymerizable carbon-carbon double bond is subjected to a condensation reaction or an addition reaction to the acrylic polymer while maintaining the radiation-polymerizable carbon-carbon double bond. One example is how to do it.

The radiation-curable adhesive preferably contains a photopolymerization initiator. Examples of the photopolymerization initiator include α-ketol compounds, acetophenone compounds, benzoin ether compounds, ketal compounds, aromatic sulfonyl chloride compounds, photoactive oxime compounds, benzophenone compounds, thioxanthone compounds, Examples include camphorquinone, halogenated ketones, acylphosphinoxides, acyl phosphonates, and the like.

Examples of the above α-ketol compounds include 4-(2-hydroxyethoxy)phenyl(2-hydroxy-2-propyl)ketone, α-hydroxy-α,α'-dimethylacetophenone, and 2-methyl-2-hydroxy Examples include propiophenone and 1-hydroxycyclohexylphenyl ketone.

Examples of the acetophenone compounds include methoxyacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxyacetophenone, 2-methyl-1-[4-(methylthio)-phenyl]-2 -morpholinopropane-1, etc.

Examples of the benzoin ether compounds include benzoin ethyl ether, benzoin isopropyl ether, anisoin methyl ether, and the like. Examples of the above-mentioned ketal compounds include benzyl dimethyl ketal.

Examples of the aromatic sulfonyl chloride compounds include 2-naphthalenesulfonyl chloride. Examples of the photoactive oxime compounds include 1-phenyl-1,2-propanedione-2-(O-ethoxycarbonyl) oxime.

Examples of the benzophenone compounds include benzophenone, benzoylbenzoic acid, and 3,3'-dimethyl-4-methoxybenzophenone.

Examples of the thioxanthone compounds include thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropyl Examples include thioxanthone.

The content of the photopolymerization initiator in the radiation-curable adhesive is, for example, 0.05 to 20 parts by weight based on 100 parts by weight of the base polymer.

The heat-foaming adhesive is an adhesive containing components that foam or expand when heated (foaming agents, heat-expandable microspheres, etc.).

Examples of the foaming agent include various inorganic foaming agents and organic foaming agents. Examples of the inorganic blowing agent include ammonium carbonate, ammonium hydrogen carbonate, sodium hydrogen carbonate, ammonium nitrite, sodium borohydride, and azides. Examples of the organic blowing agent include salt fluorinated alkanes such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; paratoluene; Hydrazine compounds such as sulfonyl hydrazide, diphenylsulfone-3,3'-disulfonyl hydrazide, 4,4'-oxybis(benzenesulfonyl hydrazide), allylbis(sulfonyl hydrazide); p-tolylenesulfonyl semicarbazide, 4,4'- Semicarbazide compounds such as oxybis(benzenesulfonyl semicarbazide); Triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; N,N'-dinitrosopentamethylenetetramine, N,N'-dimethyl- Examples include N-nitroso compounds such as N,N'-dinitrosoterephthalamide.

Examples of the thermally expandable microspheres include microspheres in which a substance that easily gasifies and expands when heated is enclosed in a shell. Examples of substances that easily gasify and expand upon heating include isobutane, propane, pentane, and the like. Thermally expandable microspheres can be produced by encapsulating a substance that easily gasifies and expands upon heating into a shell-forming substance by a coacervation method, an interfacial polymerization method, or the like. As the shell-forming substance, a substance exhibiting thermal melting property or a substance capable of bursting due to the action of thermal expansion of the encapsulating substance can be used. Examples of such substances include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, polysulfone, and the like.

Examples of the adhesive layer that does not reduce adhesive strength include a pressure-sensitive adhesive layer. Note that the pressure-sensitive adhesive layer includes a pressure-sensitive adhesive layer formed from the radiation-curable adhesive described above in connection with the adhesive force-reducible adhesive layer, which is cured by radiation irradiation in advance, but has a certain adhesive force. Contains an adhesive layer. As the adhesive forming the non-reduced adhesive layer, one type of adhesive or two or more types of adhesive may be used.

Further, the entire adhesive layer may be a non-reduced adhesive layer, or a portion thereof may be a non-reduced adhesive layer. For example, when the adhesive layer has a single-layer structure, the entire adhesive layer may be a non-adhesive adhesive layer, or any part of the adhesive layer (for example, the area to which a ring frame is attached) may be used. The area outside the central area) is a non-reducible adhesive layer, and the other area (for example, the central area where a semiconductor wafer is attached) is an adhesive layer that can reduce adhesive force. It may be an agent layer.

When the adhesive layer has a laminated structure, all the adhesive layers in the laminated structure may be non-adhesive adhesive layers, or some adhesive layers in the laminated structure may be non-adhesive adhesive layers. It may also be an adhesive layer.

An adhesive layer formed from a radiation-curable adhesive (non-irradiated radiation-curable adhesive layer) is cured by radiation irradiation (irradiated radiation-curable adhesive layer). Even if the adhesive strength is reduced by irradiation, it exhibits adhesiveness due to the contained polymer component, and it is possible to exhibit the minimum required adhesive strength for the adhesive layer of the dicing tape in the dicing process and the like.

When using an irradiated radiation-curable adhesive layer, the entire adhesive layer may be an irradiated radiation-curable adhesive layer, or a part of the adhesive layer may be It may be a radiation-curable adhesive layer that has been irradiated and the other portion is not irradiated with radiation.

In addition, in this specification, the "radiation-curable adhesive layer" refers to an adhesive layer formed from a radiation-curable adhesive, and includes a radiation-curable adhesive layer that has radiation curability and has not been irradiated with radiation, and the adhesive. It includes both a radiation-cured adhesive layer and a radiation-cured adhesive layer after the adhesive layer has been cured by radiation irradiation.

As the adhesive forming the pressure-sensitive adhesive layer, any known or commonly used pressure-sensitive adhesive can be used, and acrylic adhesives or rubber-based adhesives having an acrylic polymer as a base polymer are preferably used. I can do it. When the adhesive layer contains an acrylic polymer as a pressure-sensitive adhesive, the acrylic polymer may be a polymer containing a structural unit derived from a (meth)acrylic acid ester as the largest structural unit in mass proportion. preferable. As the acrylic polymer, for example, the acrylic polymer described as the acrylic polymer that can be included in the above-mentioned adhesive layer can be employed.

The pressure-sensitive adhesive layer is a radiation-curable acrylic pressure-sensitive adhesive layer, and preferably has a glass transition temperature of -20°C or lower (preferably -25°C or lower). The adhesive film with dicing tape having the above-mentioned adhesive layer has good adhesion to the adhesive film even in low-temperature environments, and chips with adhesive film are less likely to peel off during cool expansion at low temperatures and high speeds. Even during subsequent water washing, the adhesive film exposed outside the semiconductor wafer can be prevented from scattering. Note that the glass transition temperature is, for example, −40° C. or higher. The glass transition temperature can be measured using a known or commonly used differential scanning calorimeter.

In addition to the above-mentioned components, the adhesive layer or the adhesive forming the adhesive layer contains a crosslinking accelerator, a tackifier, an anti-aging agent, a coloring agent (pigment, dye, etc.), and other known or commonly used adhesive layers. Additives used in the above may also be blended.

Examples of the coloring agent include compounds that are colored by radiation irradiation. When containing a compound that is colored by radiation irradiation, only the portion irradiated with radiation can be colored. The compound that is colored by radiation irradiation is a compound that is colorless or light-colored before radiation irradiation, but becomes colored by radiation irradiation, and includes, for example, leuco dye. The amount of the compound that is colored by radiation irradiation is not particularly limited and can be selected as appropriate.

The thickness of the adhesive layer is not particularly limited, but is preferably 2 to 10 μm, more preferably 3 to 8 μm. When the thickness is 2 μm or more, sufficient adhesion with the adhesive film can be ensured, and the adhesive film is less likely to peel off from the adhesive layer during cool expansion at low temperatures and high speeds. When the thickness is 10 μm or less, the adhesive film has better tearability during cool expansion at low temperatures and high speeds.

The total thickness of the base material and the adhesive layer is preferably 80 μm or more. When the total thickness is 80 μm or more, the dicing tape thickness is sufficiently thick, and tearing of the dicing tape can be further suppressed. The total thickness is preferably 210 μm or less, more preferably 190 μm or less, still more preferably 160 μm or less, in order to more fully exhibit cutting performance.

When the adhesive film is a back adhesive film described below, the haze of the dicing tape is preferably 10% or less, more preferably 8% or less. When the haze is 10% or less, when laser marking is applied from the dicing tape side to the back adhesive film, the laser can easily pass through, and the laser marking can be applied more efficiently to the back adhesive film. Printing can be easily confirmed through the dicing tape.

The in-line transmittance of the dicing tape at a wavelength of 532 nm is preferably 70% or more, more preferably 75% or more. When the linear transmittance is 70% or more, when laser marking is applied to the back adhesive film from the dicing tape side, the laser can easily pass through the back adhesive film, and laser marking can be performed more efficiently on the back adhesive film. Printing by marking can be easily confirmed through the dicing tape.

(adhesive film)
The adhesive film may use an adhesive that exhibits thermosetting properties, or may use an adhesive that does not exhibit thermosetting properties. The adhesive film also has an adhesive function for holding a workpiece such as a semiconductor wafer and a frame member such as a ring frame as necessary. The adhesive film can be cut by applying tensile stress, and is used after being cut by applying tensile stress.

When the adhesive film has thermosetting properties, the adhesive film and the adhesive constituting the adhesive film may contain a thermosetting resin and, for example, a thermoplastic resin as a binder component, or may react with a curing agent. It may also contain a thermoplastic resin having a thermosetting functional group capable of forming a bond. When the adhesive constituting the adhesive film contains a thermoplastic resin having a thermosetting functional group, the adhesive does not need to contain a thermosetting resin (such as an epoxy resin). Further, when the adhesive film does not have thermosetting properties, the adhesive film and the adhesive that constitutes the adhesive film may contain a thermoplastic resin. The adhesive film may have a single layer structure or a multilayer structure.

Examples of the thermoplastic resin include natural rubber, butyl rubber, isoprene rubber, chloroprene rubber, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, polybutadiene resin, and polycarbonate resin. , thermoplastic polyimide resins, polyamide resins such as 6-nylon and 6,6-nylon, phenoxy resins, acrylic resins, saturated polyester resins such as PET and PBT, polyamideimide resins, and fluororesins. The above thermoplastic resins may be used alone or in combination of two or more. As the thermoplastic resin, an acrylic resin is preferable because it contains few ionic impurities and has high heat resistance, so that it is easy to ensure bonding reliability with an adhesive film.

It is preferable that the acrylic resin contains a structural unit derived from a hydrocarbon group-containing (meth)acrylic ester as the largest structural unit in mass proportion. Examples of the hydrocarbon group-containing (meth)acrylic ester include hydrocarbon group-containing (meth)acrylic esters exemplified as hydrocarbon group-containing (meth)acrylic esters that form an acrylic polymer that can be included in the above-mentioned adhesive layer. Meth)acrylic acid esters are mentioned.

The acrylic resin may contain a structural unit derived from another monomer component copolymerizable with the hydrocarbon group-containing (meth)acrylic ester. Examples of the other monomer components include carboxy group-containing monomers, acid anhydride monomers, hydroxy group-containing monomers, glycidyl group-containing monomers, sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, and functional group-containing monomers such as acrylamide and acrylonitrile. Examples include monomers and various polyfunctional monomers, and specifically, those exemplified as other monomer components constituting the acrylic polymer that can be included in the above-mentioned adhesive layer can be used.

When the adhesive film contains a thermosetting resin together with a thermoplastic resin, examples of the thermosetting resin include epoxy resin, phenol resin, amino resin, unsaturated polyester resin, polyurethane resin, silicone resin, and thermosetting polyimide. Examples include resin. The above thermosetting resin may be used alone or in combination of two or more. Epoxy resin is preferable as the thermosetting resin because it tends to contain less ionic impurities and the like that can cause corrosion of semiconductor chips to be die-bonded. Further, as a curing agent for epoxy resin, phenol resin is preferable.

Examples of the above 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 novolak type, ortho Examples include cresol novolak type, trishydroxyphenylmethane type, tetraphenylolethane type, hydantoin type, trisglycidyl isocyanurate type, and glycidylamine type epoxy resins. Among these, novolac type epoxy resins, biphenyl type epoxy resins, trishydroxyphenylmethane type epoxy resins, and tetraphenylolethane type epoxy resins are preferred because they are highly reactive with phenolic resins as curing agents and have excellent heat resistance.

Examples of the phenolic resin that can act as a curing agent for epoxy resins include novolac-type phenolic resins, resol-type phenolic resins, and polyoxystyrenes such as polyparaoxystyrene. Examples of the novolak type phenolic resin include phenol novolak resin, phenol aralkyl resin, cresol novolak resin, tert-butylphenol novolak resin, and nonylphenol novolak resin. The above phenol resins may be used alone or in combination of two or more. Among these, phenol novolac resins and phenol aralkyl resins are preferred from the viewpoint of tending to improve the connection reliability of the adhesive when used as a curing agent for an epoxy resin as a die bonding adhesive.

In the adhesive film, from the viewpoint of sufficiently advancing the curing reaction between the epoxy resin and the phenol resin, the phenol resin preferably contains 0.5 hydroxyl groups per equivalent of epoxy group in the epoxy resin component. It is contained in an amount of ~2.0 equivalents, more preferably 0.7 to 1.5 equivalents.

When the adhesive film contains a thermosetting resin, the content ratio of the thermosetting resin is determined based on the total mass of the adhesive film, from the viewpoint of appropriately expressing the function as a thermosetting adhesive in the adhesive film. The amount is preferably 5 to 60% by weight, more preferably 10 to 50% by weight.

When the adhesive film contains a thermoplastic resin having a thermosetting functional group, for example, an acrylic resin containing a thermosetting functional group can be used as the thermoplastic resin. The acrylic resin in this thermosetting functional group-containing acrylic resin preferably contains a structural unit derived from a hydrocarbon group-containing (meth)acrylic ester as the largest structural unit in mass proportion. Examples of the hydrocarbon group-containing (meth)acrylic ester include those exemplified as the hydrocarbon group-containing (meth)acrylic ester that forms the acrylic polymer that can be included in the above-mentioned adhesive layer.

On the other hand, examples of the thermosetting functional group in the thermosetting functional group-containing acrylic resin include a glycidyl group, a carboxy group, a hydroxy group, and an isocyanate group. Among these, a glycidyl group and a carboxy group are preferred. That is, particularly preferred as the thermosetting functional group-containing acrylic resin are glycidyl group-containing acrylic resins and carboxyl group-containing acrylic resins. Further, it is preferable to include a curing agent together with the thermosetting functional group-containing acrylic resin, and examples of the curing agent include crosslinking agents that can be included in the radiation-curable adhesive for forming the adhesive layer described above. Things can be mentioned. When the thermosetting functional group in the thermosetting functional group-containing acrylic resin is a glycidyl group, it is preferable to use a polyphenol compound as the curing agent, and for example, the various phenolic resins mentioned above can be used.

In order to achieve a certain degree of crosslinking for the adhesive film before being cured, for example, a polyfunctional compound that can react and bond with the functional group at the molecular chain end of the above-mentioned resin that may be included in the adhesive film is used. It is preferable to mix it into the adhesive film-forming resin composition as a crosslinking component. Such a configuration is preferable from the viewpoint of improving the adhesive properties of the adhesive film at high temperatures and from the viewpoint of improving the heat resistance.

Examples of the crosslinking component include polyisocyanate compounds. Examples of the polyisocyanate compound include tolylene diisocyanate, diphenylmethane diisocyanate, p-phenylene diisocyanate, 1,5-naphthalene diisocyanate, and an adduct of polyhydric alcohol and diisocyanate. Further, as the above-mentioned crosslinking component, other polyfunctional compounds such as epoxy resins may be used in combination with the polyisocyanate compound.

The content of the crosslinking component in the resin composition for forming an adhesive film is determined based on 100 parts by mass of the resin having the functional group capable of reacting and bonding with the crosslinking component, from the viewpoint of improving the cohesive force of the adhesive film formed. It is preferably 0.05 parts by mass or more, and preferably 7 parts by mass or less from the viewpoint of improving the adhesive strength of the formed adhesive film.

It is preferable that the adhesive film contains a filler. By adding a filler to the adhesive film, the physical properties of the adhesive film such as electrical conductivity, thermal conductivity, and elastic modulus can be adjusted. Examples of fillers include inorganic fillers and organic fillers, with inorganic fillers being particularly preferred.

Examples of inorganic fillers include aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, calcium silicate, magnesium silicate, calcium oxide, magnesium oxide, aluminum oxide, aluminum nitride, aluminum borate whiskers, boron nitride, and crystals. In addition to crystalline silica and amorphous silica, metals such as aluminum, gold, silver, copper, and nickel, alloys, amorphous carbon black, and graphite may be used. The filler may have various shapes such as spherical, acicular, and flaky. As the above-mentioned filler, only one type may be used, or two or more types may be used.

The average particle size of the filler is preferably 0.005 to 10 μm, more preferably 0.005 to 1 μm. When the average particle size is 0.005 μm or more, wettability and adhesion to adherends such as semiconductor wafers are further improved. When the average particle size is 10 μm or less, the effect of the filler added to impart each of the above properties can be made sufficient, and heat resistance can be ensured. The average particle size of the filler can be determined using, for example, a photometric particle size distribution analyzer (eg, trade name "LA-910", manufactured by Horiba, Ltd.).

The adhesive film may contain other components as necessary. Examples of the other components include a curing catalyst, a flame retardant, a silane coupling agent, an ion trapping agent, and a dye. The other additives mentioned above may be used alone or in combination of two or more.

Examples of the flame retardant include antimony trioxide, antimony pentoxide, and brominated epoxy resin.

Examples of the silane coupling agent include β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and γ-glycidoxypropylmethyldiethoxysilane.

Examples of the ion trapping agent include hydrotalcites, bismuth hydroxide, hydrated antimony oxide (for example, "IXE-300" manufactured by Toagosei Co., Ltd.), and zirconium phosphate with a specific structure (for example, "IXE-300" manufactured by Toagosei Co., Ltd.). Examples include "IXE-100"), magnesium silicate (for example, "Kyoward 600" manufactured by Kyowa Chemical Industry Co., Ltd.), and aluminum silicate (for example, "Kyoward 700" manufactured by Kyowa Chemical Industry Co., Ltd.).

Compounds that can form complexes with metal ions can also be used as ion trapping agents. Examples of such compounds include triazole compounds, tetrazole compounds, and bipyridyl compounds. Among these, triazole compounds are preferred from the viewpoint of stability of complexes formed with metal ions.

Examples of the triazole 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-t-butylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3-t-butyl-5-methylphenyl)- 5-chlorobenzotriazole, 2-(2-hydroxy-3,5-di-t-amylphenyl)benzotriazole, 2-(2-hydroxy-5-t-octylphenyl)benzotriazole, 6-(2-benzo triazolyl)-4-t-octyl-6'-t-butyl-4'-methyl-2,2'-methylenebisphenol, 1-(2',3'-hydroxypropyl)benzotriazole, 1-(1 ,2-dicarboxydiethyl)benzotriazole, 1-(2-ethylhexylaminomethyl)benzotriazole, 2,4-di-t-pentyl-6-{(H-benzotriazol-1-yl)methyl}phenol, 2 -(2-hydroxy-5-t-butylphenyl)-2H-benzotriazole, 3-(2H-benzotriazol-2-yl)-5-(1,1-dimethylethyl)-4-hydroxy, 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-yl)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-t-butylphenol, 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2 -Hydroxy-5-t-octylphenyl)-benzotriazole, 2-(3-t-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole, 2-(2-hydroxy-3,5- di-t-amylphenyl)benzotriazole, 2-(2-hydroxy-3,5-di-t-butylphenyl)-5-chloro-benzotriazole, 2-[2-hydroxy-3,5-di(1 ,1-dimethylbenzyl)phenyl]-2H-benzotriazole, 2,2'-methylenebis[6-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol ], 2-[2-hydroxy-3,5-bis(α,α-dimethylbenzyl)phenyl]-2H-benzotriazole, methyl-3-[3-(2H-benzotriazol-2-yl)-5- Examples include t-butyl-4-hydroxyphenyl]propionate.

Further, specific hydroxyl group-containing compounds such as quinol compounds, hydroxyanthraquinone compounds, and polyphenol compounds can also be used as ion trapping agents. Specific examples of such hydroxyl group-containing compounds include 1,2-benzenediol, alizarin, anthralphine, tannin, gallic acid, methyl gallate, and pyrogallol.

The thickness of the adhesive film (total thickness in the case of a laminate) is not particularly limited, but is, for example, 1 to 200 μm. The upper limit is preferably 100 μm, more preferably 80 μm. The lower limit is preferably 3 μm, more preferably 5 μm.

The adhesive film may be a film for die-bonding a work onto a wiring board or other work (die-bonding film), or a film used in close contact with the back surface of a semiconductor (semiconductor back-adhesion film). Semiconductor back adhesive films, such as back protection films, are usually blended with a coloring agent so that engraved information can be added by laser marking, and have light blocking properties. In this specification, the semiconductor back-adhesion film may be simply referred to as a "back-adhesion film."

In this specification, the "front surface" of a semiconductor (workpiece) refers to the surface on which bumps are formed for flip-chip mounting of the workpiece, and the "back surface" refers to the side opposite to the surface, that is, the surface on which bumps are formed. This refers to the side that is not covered. The term "back contact film" refers to a film that is used in close contact with the back surface of a semiconductor, and includes a film (semiconductor back surface protective film) for forming a protective film on the back surface (so-called back surface) of a semiconductor chip. In addition, in this specification, a "back-adhesion film" refers to a film that remains in close contact with the back surface of a workpiece even after it is mounted on a semiconductor device, and is peeled off during the manufacturing process of semiconductor devices such as dicing tapes and separators. Layers are not included. The back adhesive film may have a single layer structure or a multilayer structure.

When the adhesive film is a back contact film, the adhesive film with dicing tape is used as a dicing tape integrated semiconductor back contact film (dicing tape integrated back contact film). That is, the dicing tape-integrated back adhesive film includes a dicing tape having a laminated structure including a base material and an adhesive layer, and a back adhesive film that is releasably adhered to the adhesive layer of the dicing tape. It is a form that is equipped with. Moreover, when the said adhesive film is a die bond film, the said adhesive film with a dicing tape is used as a dicing die bond film.

When the above-mentioned back adhesive film has a multilayer structure, it has a laminated structure including a back adhesive layer having an adhesion surface to the back of the workpiece and a laser mark layer to which marking information can be added by laser marking. It's okay. The back surface adhesion layer may have thermosetting properties so that after being adhered to the back surface of the workpiece, it can be thermally cured to adhere to and protect the back surface of the workpiece. In addition, if the back adhesive layer is non-thermosetting, the back adhesive layer will adhere to the back of the workpiece and protect it through pressure-sensitive interface adhesion (wettability) or chemical bonding. Is possible. Laser marking is performed on the surface of the laser mark layer during the manufacturing process of the semiconductor device. The back adhesive film having such a laminated structure has a laminated structure in which the back adhesive layer is thermally cured by heat treatment at 120° C. for 2 hours, while the laser mark layer is not substantially thermally cured. can be taken. In addition, in the back adhesive film, the layer that is not substantially thermoset by heat treatment at 120° C. for 2 hours includes a thermosetting layer that has already been cured. The back adhesive layer and the laser mark layer may each have a single layer structure or a multilayer structure.

The laser mark layer is preferably a thermosetting layer (thermocured layer) in which a thermosetting component is thermoset at the time of laser marking. The thermoset laser mark layer is formed by curing a thermosetting resin composition layer formed from the resin composition forming the laser mark layer.

When the back adhesive film has a multilayer structure including a back adhesive layer and a laser marking layer, the ratio of the thickness of the laser mark layer to the thickness of the back adhesive layer is preferably 1 or more, more preferably 1.5 or more. , more preferably 2 or more. The above ratio is, for example, 10 or less.

FIG. 2 shows an embodiment of an adhesive film with a dicing tape in which the back adhesive film has a multilayer structure. As shown in FIG. 2, the adhesive film with dicing tape 1 includes a dicing tape 10 and a back adhesive film 20a laminated on the adhesive layer 12 of the dicing tape 10. The back adhesive film 20a has a multilayer structure including a back adhesive layer 21a and a laser mark layer 22a, and the laser mark layer 22a is peelably adhered to the adhesive layer 12 of the dicing tape 10. The back adhesive film 20a can be used by being attached to the back surface of a workpiece and then thermally cured.

The adhesive film with dicing tape may have a separator. Specifically, each adhesive film with dicing tape may be in the form of a sheet with a separator, or the separator may be a long separator on which a plurality of adhesive films with dicing tape are arranged and the The separator may be wound into a roll.

The separator is an element for covering and protecting the adhesive film surface of the adhesive film with dicing tape, and is peeled off from the adhesive film when the adhesive film with dicing tape is used. Examples of the separator include polyethylene terephthalate (PET) film, polyethylene film, polypropylene film, and plastic films and papers whose surfaces are coated with a release agent such as a fluorine-based release agent or a long-chain alkyl acrylate release agent. The thickness of the separator is, for example, 5 to 200 μm.

The adhesive film with dicing tape 1, which is an embodiment of the adhesive film with a dicing tape, is manufactured, for example, as follows.

First, the base material 11 can be obtained by forming a film using a known or commonly used film forming method. Examples of the film forming method include a calendar film forming method, a casting method in an organic solvent, a closed system inflation extrusion method, a T-die extrusion method, a coextrusion method, and a dry lamination method.

Next, a composition for forming the adhesive layer 12 (adhesive composition) containing an adhesive for forming the adhesive layer 12, a solvent, etc. is applied onto the base material 11 to form a coating film. If necessary, the adhesive layer 12 can be formed by solidifying the coating film by removing the solvent, curing, or the like. Examples of the above coating method include known and commonly used coating methods such as roll coating, screen coating, and gravure coating. Further, the desolvation conditions include, for example, a temperature of 80 to 150° C. and a time of 0.5 to 5 minutes.

Alternatively, the adhesive layer 12 may be formed by coating the adhesive composition on the separator to form a coating film, and then solidifying the coating film under the above-mentioned solvent removal conditions. Thereafter, the adhesive layer 12 is bonded together with the separator onto the base material 11. The dicing tape 10 can be produced as described above.

In the case of the adhesive film 1 with dicing tape shown in FIG. 1, for the adhesive film 20, first, a composition (adhesive composition) for forming the adhesive film 20 containing a resin, a filler, a curing catalyst, a solvent, etc. is prepared. Next, after applying the adhesive composition onto the separator to form a coating film, the coating film is solidified by solvent removal, curing, etc., as necessary, to form the adhesive film 20. The coating method is not particularly limited, and examples thereof include known and commonly used coating methods such as roll coating, screen coating, and gravure coating. Further, the solvent removal conditions are, for example, at a temperature of 70 to 160° C. and a time of 1 to 5 minutes.

In the case of the adhesive film 1 with dicing tape shown in FIG. 2, for the back adhesive film 20a which is an adhesive film, first, a back adhesive layer 21a and a laser mark layer 22a are separately produced. The back adhesive layer 21a is formed by applying a resin composition (adhesive composition) for forming the back adhesive layer 21a onto the separator to form a resin composition layer, and then removing the solvent and curing by heating. It can be produced by solidifying a material layer. In producing the back adhesive layer 21a, the heating temperature is, for example, 90 to 150° C., and the heating time is, for example, 1 to 2 minutes. Examples of methods for applying the resin composition include roll coating, screen coating, and gravure coating. On the other hand, the laser mark layer 22a is formed by coating a resin composition for forming the laser mark layer 22a on a separator to form a resin composition layer, and then removing the solvent and curing by heating to solidify the resin composition layer. It can be produced by In producing the laser mark layer 22a, the heating temperature is, for example, 90 to 160° C., and the heating time is, for example, 2 to 4 minutes. The back adhesive layer 21a and the laser mark layer 22a can be produced in a form that each includes a separator. Then, the exposed surfaces of the back adhesive layer 21a and the laser mark layer 22a are bonded together, and then punched to have the desired planar projection shape and planar projected area, and the back adhesive layer 21a and the laser mark layer 22a are bonded together. A back adhesive film 20a having a laminated structure is produced.

Subsequently, the separators are peeled off from the dicing tape 10 and the adhesive film 20, respectively, and the adhesive film 20 and the adhesive layer 12 are bonded together so that they become bonding surfaces. When the adhesive film 20 is a back contact film 20a, the laser mark layer 22a side of the back contact film 20a is bonded to the adhesive layer 12 side of the dicing tape 10. The bonding can be performed, for example, by pressure bonding. At this time, the lamination temperature is not particularly limited, and is preferably, for example, 30 to 50°C, more preferably 35 to 45°C. Further, the linear pressure is not particularly limited, and is preferably, for example, 0.1 to 20 kgf/cm, more preferably 1 to 10 kgf/cm.

As described above, when the adhesive layer 12 is a radiation-curable adhesive layer, when the adhesive layer 12 is irradiated with radiation such as ultraviolet rays after the adhesive film 20 is attached, the adhesive layer 12 is cured from the side of the base material 11, for example. The agent layer 12 is irradiated with radiation at a dose of, for example, 50 to 500 mJ, preferably 100 to 300 mJ.

The area (irradiation area R) in which irradiation is performed as a measure to reduce the adhesive force of the adhesive layer 12 in the adhesive film with dicing tape 1 usually excludes the peripheral part within the adhesive film 20 bonding area in the adhesive layer 12. It is an area. When providing the irradiation region R partially, it can be done through a photomask in which a pattern corresponding to the region other than the irradiation region R is formed. Another method is to form the irradiation region R by irradiating radiation spot-wise.

In the manner described above, for example, the adhesive film 1 with dicing tape shown in FIGS. 1 and 2 can be produced.

The adhesive film with dicing tape 1, which is an embodiment of the adhesive film with a dicing tape, is manufactured, for example, as follows.

[Method for manufacturing semiconductor device]
A semiconductor device can be manufactured using the adhesive film with a dicing tape. Specifically, the step of attaching a divided semiconductor wafer including a plurality of semiconductor chips, or a semiconductor wafer that can be singulated into a plurality of semiconductor chips, to the adhesive film side of the adhesive film with a dicing tape ("process") is performed. A) and a step of expanding the dicing tape in the adhesive film with the dicing tape under relatively low temperature conditions and cutting at least the adhesive film to obtain a semiconductor chip with the adhesive film ( (sometimes referred to as "Process B"), and a step (sometimes referred to as "Process C") of expanding the dicing tape to widen the distance between the semiconductor chips with adhesive films under relatively high temperature conditions. A semiconductor device can be manufactured by a manufacturing method including a step (sometimes referred to as "step D") of picking up the semiconductor chip with the adhesive film.

The divided semiconductor wafer including the plurality of semiconductor chips used in step A, or the semiconductor wafer that can be singulated into a plurality of semiconductor chips, can be obtained as follows. First, as shown in FIGS. 3A and 3B, dividing grooves 30a are formed in the semiconductor wafer W (dividing groove forming step). The semiconductor wafer W has a first surface Wa and a second surface Wb. Various semiconductor elements (not shown) have already been formed on the first surface Wa side of the semiconductor wafer W, and wiring structures etc. (not shown) necessary for the semiconductor elements have already been formed on the first surface Wa. has been done.

Then, after bonding the wafer processing tape T1 having the adhesive surface T1a to the second surface Wb side of the semiconductor wafer W, the semiconductor wafer W is held on the wafer processing tape T1. A dividing groove 30a having a desired depth is formed on the surface Wa side using a rotating blade such as a dicing machine. The dividing groove 30a is a gap for separating the semiconductor wafer W into semiconductor chips (the dividing groove 30a is schematically represented by a thick line in FIGS. 3 to 5).

Next, as shown in FIG. 3(c), the wafer processing tape T2 having the adhesive surface T2a is attached to the first surface Wa side of the semiconductor wafer W, and the wafer processing tape T1 is removed from the semiconductor wafer W. and peeling.

Next, as shown in FIG. 3(d), with the semiconductor wafer W held on the wafer processing tape T2, the semiconductor wafer W is thinned by grinding from the second surface Wb until it reaches a desired thickness. (wafer thinning process). Grinding can be performed using a grinding device equipped with a grinding wheel. Through this wafer thinning process, in this embodiment, a semiconductor wafer 30A that can be singulated into a plurality of semiconductor chips 31 is formed.

Specifically, the semiconductor wafer 30A has a portion (connecting portion) that connects portions of the wafer that will be singulated into a plurality of semiconductor chips 31 on the second surface Wb side. The thickness of the connecting portion in the semiconductor wafer 30A, that is, the distance between the second surface Wb of the semiconductor wafer 30A and the tip of the dividing groove 30a on the second surface Wb side is, for example, 1 to 30 μm, preferably 3 to 20 μm. It is.

(Process A)
In step A, a divided semiconductor wafer including a plurality of semiconductor chips or a semiconductor wafer that can be singulated into a plurality of semiconductor chips is attached to the adhesive film 20 side of the adhesive film 1 with a dicing tape.

In one embodiment of step A, as shown in FIG. 4(a), the semiconductor wafer 30A held by the wafer processing tape T2 is bonded to the adhesive film 20 of the adhesive film 1 with dicing tape. Thereafter, as shown in FIG. 4(b), the wafer processing tape T2 is peeled off from the semiconductor wafer 30A.

Note that after bonding the semiconductor wafer 30A to the adhesive film 20, the adhesive layer 12 may be irradiated with radiation such as ultraviolet rays from the base material 11 side. The irradiation amount is, for example, 50 to 500 mJ/cm ² , preferably 100 to 300 mJ/cm ² . The area (irradiation area R shown in FIG. 1) where irradiation is performed as a measure to reduce the adhesive force of the adhesive layer 12 in the adhesive film with dicing tape 1 is, for example, the area in the adhesive film 20 bonding area of the adhesive layer 12. This is the area excluding the periphery.

(Process B)
In step B, the dicing tape 10 in the adhesive film with dicing tape 1 is expanded under relatively low temperature conditions, and at least the adhesive film 20 is cut to obtain a semiconductor chip with an adhesive film.

In an embodiment in process B, first, after pasting the ring frame 41 on the adhesive layer 12 of the dicing tape 10 in the adhesive film with dicing tape 1, as shown in FIG. 5(a), the semiconductor wafer 30A is attached. The accompanying adhesive film 1 with dicing tape is fixed to a holder 42 of an expanding device.

Next, a first expansion process (cool expansion process) under relatively low temperature conditions is performed as shown in FIG. The adhesive film 20 of the dicing tape-attached adhesive film 1 is cut into small pieces of the adhesive film 21 to obtain the adhesive film-attached semiconductor chip 31.

In the cool expansion process, a hollow cylindrical push-up member 43 provided in the expansion device is brought into contact with the dicing tape 10 at the lower side in the figure of the adhesive film with dicing tape 1 and raised, thereby dicing the bonded semiconductor wafer 30A. The dicing tape 10 of the tape-attached adhesive film 1 is expanded so as to be stretched in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer 30A.

This expansion is performed under conditions in which the dicing tape 10 generates a tensile stress in the range of 15 to 32 MPa, preferably 20 to 32 MPa. The temperature conditions in the cool expansion step are, for example, 0°C or lower, preferably -20 to -5°C, more preferably -15 to -5°C, and more preferably -15°C. The expansion speed (the speed at which the push-up member 43 is raised) in the cool expansion step is preferably 50 to 400 mm/sec, and when carried out at high speed, preferably 100 to 400 mm/sec. Further, the amount of expansion in the cool expansion step is preferably 3 to 20 mm.

In step B, when the semiconductor wafer 30A that can be singulated into a plurality of semiconductor chips is used, the semiconductor wafer 30A is broken at a thin and easily broken portion, and the semiconductor chips 31 are singulated. At the same time, in step B, deformation is suppressed in each area where each semiconductor chip 31 is in close contact with the adhesive film 20 that is in close contact with the adhesive layer 12 of the dicing tape 10 to be expanded. Tensile stress generated in the dicing tape 10 acts on the portions of the dividing grooves located in the vertical direction in the figure without such a deformation suppressing effect. As a result, the adhesive film 20 is cut at a location located perpendicular to the dividing groove between the semiconductor chips 31. After cutting by expanding, the pushing up member 43 is lowered to release the expanded state of the dicing tape 10, as shown in FIG. 5(c).

(Process C)
In step C, the dicing tape 10 is expanded under relatively high temperature conditions to widen the distance between the semiconductor chips with adhesive films.

In one embodiment of process C, first, a second expansion process (normal temperature expansion process) under relatively high temperature conditions is performed as shown in FIG. 6(a), and the distance between semiconductor chips 31 with adhesive films is Increase (separation distance).

In step C, the hollow cylindrical push-up member 43 of the expanding device is raised again to expand the dicing tape 10 of the adhesive film 1 with dicing tape. The temperature conditions in the second expanding step are, for example, 10°C or higher, preferably 15 to 30°C. The expansion speed (the speed at which the push-up member 43 is raised) in the second expansion step is, for example, 0.1 to 10 mm/sec, preferably 0.3 to 1 mm/sec. In step C, the distance between the adhesive film-attached semiconductor chips 31 is increased to such an extent that the adhesive film-attached semiconductor chips 31 can be appropriately picked up from the dicing tape 10 in a later-described pick-up process. After increasing the separation distance by expanding, as shown in FIG. 6(b), the push-up member 43 is lowered to release the expanded state of the dicing tape 10.

From the viewpoint of suppressing the narrowing of the distance between the semiconductor chips 31 with adhesive films on the dicing tape 10 after canceling the expanded state, before canceling the expanded state, the portion of the dicing tape 10 outside the semiconductor chip 31 holding area is It is preferable to shrink it by heating.

After step C, a cleaning step may be included as necessary, in which the semiconductor chip 31 side of the dicing tape 10 with the adhesive film attached semiconductor chip 31 is cleaned using a cleaning liquid such as water.

(Process D)
In step D (pickup step), the semiconductor chips with adhesive films that have been separated into pieces are picked up. In one embodiment in step D, after passing through the cleaning step as necessary, the semiconductor chip 31 with adhesive film is picked up from the dicing tape 10, as shown in FIG. For example, for the semiconductor chip 31 with an adhesive film to be picked up, the pin member 44 of the pickup mechanism is raised on the lower side of the dicing tape 10 in the figure, pushed up through the dicing tape 10, and then held by suction by the suction jig 45. . In the pick-up process, the speed of pushing up the pin member 44 is, for example, 1 to 100 mm/sec, and the amount of pushing up of the pin member 44 is, for example, 50 to 3000 μm.

The method for manufacturing a semiconductor device described above may include steps other than steps A to D. For example, in one embodiment, as shown in FIG. 8A, the picked up semiconductor chip 31 with an adhesive film is temporarily fixed to an adherend 51 via the adhesive film 21 (temporary fixing step).

Examples of the adherend 51 include a lead frame, a TAB (Tape Automated Bonding) film, a wiring board, a separately manufactured semiconductor chip, and the like. The shear adhesive force at 25° C. during temporary fixation of the adhesive film 21 to the adherend 51 is preferably 0.2 MPa or more, more preferably 0.2 to 10 MPa. The configuration in which the shear adhesive strength of the adhesive film 21 is 0.2 MPa or more is such that the bonding surface between the adhesive film 21 and the semiconductor chip 31 or the adherend 51 is not sheared due to ultrasonic vibration or heating in the wire bonding process described below. Wire bonding can be performed appropriately while suppressing deformation. Further, the shear adhesive force at 175° C. during temporary fixation of the adhesive film 21 to the adherend 51 is preferably 0.01 MPa or more, more preferably 0.01 to 5 MPa.

Next, as shown in FIG. 8B, the electrode pads (not shown) of the semiconductor chip 31 and the terminal portions (not shown) of the adherend 51 are electrically connected via the bonding wires 52 ( wire bonding process).

Connections between the electrode pads of the semiconductor chip 31 and the terminal portions of the adherend 51 and the bonding wires 52 can be realized by ultrasonic welding accompanied by heating, and are performed without thermosetting the adhesive film 21. As the bonding wire 52, for example, a gold wire, an aluminum wire, a copper wire, etc. can be used. The wire heating temperature in wire bonding is, for example, 80 to 250°C, preferably 80 to 220°C. Further, the heating time is from several seconds to several minutes.

Next, as shown in FIG. 8C, the semiconductor chip 31 is sealed with a sealing resin 53 for protecting the semiconductor chip 31 and bonding wires 52 on the adherend 51 (sealing step).

In the sealing process, thermal curing of the adhesive film 21 progresses. In the sealing process, 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, epoxy resin can be used. In the sealing step, the heating temperature for forming the sealing resin 53 is, for example, 165 to 185° C., and the heating time is, for example, 60 seconds to several minutes.

If the curing of the sealing resin 53 does not progress sufficiently in the sealing process, a post-curing process for completely curing the sealing resin 53 is performed after the sealing process. Even if the adhesive film 21 is not completely thermally cured in the sealing process, the adhesive film 21 can be completely thermally cured together with the sealing resin 53 in the post-curing process. In the post-curing step, the heating temperature is, for example, 165 to 185° C., and the heating time is, for example, 0.5 to 8 hours.

In the above embodiment, as described above, after the adhesive film-attached semiconductor chip 31 is temporarily fixed to the adherend 51, the wire bonding process is performed without completely thermosetting the adhesive film 21. Instead of such a configuration, in the method for manufacturing a semiconductor device described above, after temporarily fixing the semiconductor chip 31 with an adhesive film to the adherend 51, the wire bonding process may be performed after the adhesive film 21 is thermally cured. good.

In the method for manufacturing a semiconductor device described above, as another embodiment, a wafer thinning process shown in FIG. 9 may be performed instead of the wafer thinning process described above with reference to FIG. 3(d). After passing through the process described above with reference to FIG. 3(c), in the wafer thinning step shown in FIG. The semiconductor wafer segment 30B is thinned by grinding from the second surface Wb until it reaches the wafer processing tape T2, thereby forming a semiconductor wafer segment 30B including a plurality of semiconductor chips 31 and held by the wafer processing tape T2.

In the wafer thinning step, a method (first method) may be adopted in which the wafer is ground until the dividing groove 30a is exposed on the second surface Wb side, or a method may be adopted in which the wafer is ground from the second surface Wb side to the dividing groove 30a. A method (second method) may be adopted. Depending on the method adopted, the depth from the first surface Wa of the dividing groove 30a formed as described above with reference to FIGS. 3(a) and 3(b) is determined as appropriate.

In FIG. 9, the dividing groove 30a that has undergone the first method or the dividing groove 30a that has undergone the second method and cracks connected thereto are schematically represented by thick lines. In the above method for manufacturing a semiconductor device, in step A, the semiconductor wafer division body 30B produced in this way is used instead of the semiconductor wafer 30A, and each of the semiconductor wafer division bodies described above with reference to FIGS. 4 to 8 is used. You may perform the process.

10(a) and 10(b) represent step B in this embodiment, that is, the first expanding step (cool expanding step) performed after the semiconductor wafer divided bodies 30B are bonded to the adhesive film 1 with dicing tape. .

In step B in this embodiment, a hollow cylindrical push-up member 43 provided in the expanding device is brought into contact with the dicing tape 10 at the lower side in the figure of the adhesive film with dicing tape 1 and raised, and the semiconductor wafer divided body 30B is raised. The dicing tape 10 of the bonded dicing tape-attached adhesive film 1 is expanded so as to be stretched in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer divided body 30B.

This expansion is performed under conditions in which a tensile stress is generated in the dicing tape 10, for example, in a range of 5 to 28 MPa, preferably 8 to 25 MPa. The temperature conditions in the cool expansion step are, for example, 0°C or lower, preferably -20 to -5°C, more preferably -15 to -5°C, and more preferably -15°C. The expansion speed (the speed at which the push-up member 43 is raised) in the cool expansion step is preferably 50 to 400 mm/sec, and when carried out at high speed, preferably 100 to 400 mm/sec. Further, the amount of expansion in the cool expansion step is preferably 3 to 20 mm.

Through such a cool expansion process, the adhesive film 20 of the adhesive film with dicing tape 1 is cut into small pieces of the adhesive film 21 to obtain the semiconductor chip 31 with the adhesive film. Specifically, in the cool expansion process, deformation occurs in each region of the adhesive film 20 that is in close contact with the adhesive layer 12 of the dicing tape 10 to be expanded, where each semiconductor chip 31 of the semiconductor wafer divided body 30B is in close contact. On the other hand, the tensile stress generated in the dicing tape 10 acts on the portions of the dividing grooves 30a between the semiconductor chips 31 located in the vertical direction in the figure without such a deformation suppressing effect. As a result, the adhesive film 20 is cut at a portion of the dividing groove 30a between the semiconductor chips 31 located in the vertical direction in the figure.

In the method for manufacturing a semiconductor device described above, as a further embodiment, instead of the semiconductor wafer 30A or the semiconductor wafer segment 30B used in step A, a semiconductor wafer 30C manufactured as follows may be used.

In this embodiment, as shown in FIGS. 11(a) and 11(b), first, a modified region 30b is formed in the semiconductor wafer W. The semiconductor wafer W has a first surface Wa and a second surface Wb. Various semiconductor elements (not shown) have already been formed on the first surface Wa side of the semiconductor wafer W, and wiring structures etc. (not shown) necessary for the semiconductor elements have already been formed on the first surface Wa. has been done.

Then, after bonding the wafer processing tape T3 having the adhesive surface T3a to the first surface Wa side of the semiconductor wafer W, with the semiconductor wafer W held by the wafer processing tape T3, a light converging point is placed inside the wafer. The combined laser beams are irradiated onto the semiconductor wafer W along the planned dividing line from the side opposite to the wafer processing tape T3, and the semiconductor wafer W is modified by ablation due to multiphoton absorption. A region 30b is formed. The modified region 30b is a weakened region for separating the semiconductor wafer W into semiconductor chips.

The method of forming modified regions 30b on the planned dividing line in a semiconductor wafer by laser beam irradiation is described in detail in, for example, Japanese Patent Laid-Open No. 2002-192370, but the laser beam irradiation conditions in this embodiment are, for example, Adjustments will be made as appropriate within the following conditions.

<Laser light irradiation conditions>
(A) Laser light Laser light source Semiconductor laser excitation Nd:YAG laser Wavelength 1064nm
Laser beam spot cross-sectional area 3.14×10 ^-8 cm ²
Oscillation form Q-switch pulse Repetition frequency 100kHz or less Pulse width 1μs or less Output 1mJ or less Laser light quality TEM00
Polarization characteristics Linearly polarized light (B) condensing lens Magnification 100x or less NA 0.55
Transmittance for laser light wavelength: 100% or less (C) Movement speed of the processing table on which the semiconductor substrate is placed: 280 mm/sec or less

Next, as shown in FIG. 11(c), with the semiconductor wafer W held on the wafer processing tape T3, the semiconductor wafer W is thinned by grinding from the second surface Wb until it reaches a desired thickness. This forms a semiconductor wafer 30C that can be singulated into a plurality of semiconductor chips 31 (wafer thinning step).

In the above method for manufacturing a semiconductor device, in step A, the semiconductor wafer 30C produced in this way as a singulated semiconductor wafer is used instead of the semiconductor wafer 30A, and the semiconductor wafer 30C as described above with reference to FIGS. 4 to 8 is used. Each step may be performed.

12(a) and 12(b) represent step B in this embodiment, that is, the first expanding step (cool expanding step) performed after the semiconductor wafer 30C is bonded to the adhesive film 1 with dicing tape.

In the cool expansion process, a hollow cylindrical push-up member 43 provided in the expansion device is brought into contact with the dicing tape 10 at the lower side in the figure of the adhesive film with dicing tape 1 and raised, thereby dicing the bonded semiconductor wafer 30C. The dicing tape 10 of the tape-attached adhesive film 1 is expanded so as to be stretched in two-dimensional directions including the radial direction and the circumferential direction of the semiconductor wafer 30C.

This expansion is performed under conditions in which a tensile stress is generated in the dicing tape 10, for example, in a range of 5 to 28 MPa, preferably 8 to 25 MPa. The temperature conditions in the cool expansion step are, for example, 0°C or lower, preferably -20 to -5°C, more preferably -15 to -5°C, and more preferably -15°C. The expansion speed (the speed at which the push-up member 43 is raised) in the cool expansion step is preferably 50 to 400 mm/sec, and when carried out at high speed, preferably 100 to 400 mm/sec. Further, the amount of expansion in the cool expansion step is preferably 3 to 20 mm.

Through such a cool expansion process, the adhesive film 20 of the adhesive film with dicing tape 1 is cut into small pieces of the adhesive film 21 to obtain the semiconductor chip 31 with the adhesive film. Specifically, in the cool expansion process, cracks are formed in the fragile modified region 30b of the semiconductor wafer 30C, and the semiconductor chips 31 are separated into pieces. At the same time, in the cool expansion process, deformation of the adhesive film 20 that is in close contact with the adhesive layer 12 of the dicing tape 10 to be expanded is suppressed in each region where each semiconductor chip 31 of the semiconductor wafer 30C is in close contact. On the other hand, the tensile stress generated in the dicing tape 10 acts on the portions of the wafer located in the vertical direction in the figure where cracks are formed, without such a deformation suppressing effect occurring. As a result, the adhesive film 20 is fractured at the location where the crack is formed between the semiconductor chips 31 and which is located in the vertical direction in the figure.

In addition, in the above method for manufacturing a semiconductor device, the adhesive film with dicing tape 1 can be used to obtain a semiconductor chip with an adhesive film as described above, but it can also be used for three-dimensional mounting by stacking a plurality of semiconductor chips. It can also be used to obtain a semiconductor chip with an adhesive film in cases where the adhesive film is attached to a semiconductor chip. A spacer may be interposed between the semiconductor chips 31 in such a three-dimensional mounting together with the adhesive film 21, or there may be no spacer interposed.

The present invention will be explained in more detail with reference to Examples below, but the present invention is not limited to these Examples in any way. In addition, the composition of each component constituting the adhesive film in Examples and Comparative Examples is shown in the table. In the tables, each number representing a composition is a relative "parts by weight" within the composition.

Example 1
(dicing tape)
In a reaction vessel equipped with a cooling tube, a nitrogen inlet tube, a thermometer, and a stirring device, 100 moles of 2-ethylhexyl acrylate (2EHA), 30 moles of 2-hydroxyethyl acrylate (HEA), and acryloylmorpholine ( AM), 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 heated at 61°C for 6 hours in a nitrogen atmosphere. (polymerization reaction). Thereby, a polymer solution containing the acrylic polymer P ₁ was obtained.

Next, a mixture containing a polymer solution containing this acrylic polymer P ₁ , 2-methacryloyloxyethyl isocyanate (MOI), and dibutyltin dilaurylate as an addition reaction catalyst was heated at 50°C for 48 hours in an air atmosphere. (addition reaction). In the reaction solution, the amount of MOI is 25 mol. Further, in the reaction solution, the amount of dibutyltin dilaurylate blended is 0.01 parts by mass based on 100 parts by mass of the acrylic polymer P ₁ . Through this addition reaction, a polymer solution containing an acrylic polymer P ₂ having a methacrylate group in its side chain (an acrylic polymer containing a structural unit derived from an isocyanate compound containing an unsaturated functional group) was obtained.

Next, 1 part by mass of a polyisocyanate compound (trade name "Coronate L", manufactured by Tosoh Corporation) and 2 parts by mass of a photopolymerization initiator (for 100 parts by mass of acrylic polymer P ₂ ) were added to the polymer solution. (trade name "Irgacure 127", manufactured by BASF) and mixed, and further diluted with toluene to obtain an adhesive composition.

Next, the adhesive composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form an adhesive composition layer. . Next, this composition layer was heated at 120° C. for 2 minutes to remove the solvent, thereby forming an adhesive layer with a thickness of 5 μm on the PET separator.

Next, using a laminator, plastic film A (ionomer base material (12.5 μm)/polyurethane base material (75 μm)/ionomer base material (12.5 μm)) was applied to the exposed surface of this adhesive layer as a base material. Three-layer structure, base material thickness: 100 μm) were bonded together at room temperature. This bonded body was then stored at 50° C. for 24 hours. The dicing tape (thickness: 105 μm) of Example 1 was produced as described above.

(Preparation of back adhesive film)
100 parts by mass of acrylic resin (trade name "Teisan Resin SG-708-6", glass transition temperature: 4°C, manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name "JER YL980", Mitsubishi Chemical Corporation) 29 parts by mass of epoxy resin E ₂ (product name "KI-3000-4", manufactured by Nippon Steel Chemical Co., Ltd.), and 44 parts by mass of epoxy resin E 2 (product name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) ), 206 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.), and thermosetting catalyst C (trade name "Cure Sol 2PHZ", manufactured by Shikoku Kasei Co., Ltd.). 1 part by mass (manufactured by Kogyo Co., Ltd.) and 13 parts by mass of a visible light-absorbing dark blue dye (trade name "OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.) were added to methyl ethyl ketone and mixed to a solid content concentration of 36 mass. % resin composition was obtained. Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and then punched into a disk shape with a diameter of 315 mm. As described above, a semiconductor back adhesive film (thermosetting semiconductor back adhesive film) of Example 1 having a thickness of 15 μm was produced on a PET separator.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Example 1, and the semiconductor back adhesive film of Example 1 was laminated to the exposed adhesive layer using a laminator to produce the adhesive film with dicing tape of Example 1.

Example 2
(Preparation of back adhesive film)
100 parts by mass of acrylic resin (trade name "Teisan Resin SG-708-6", glass transition temperature: 4°C, manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name "JER YL980", Mitsubishi Chemical Corporation) (manufactured by Nippon Steel Chemical Co., Ltd.), 7 parts by mass of epoxy resin E ₂ (trade name "KI-3000-4", manufactured by Nippon Steel Chemical Co., Ltd.), and phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.). ), 103 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.), and thermosetting catalyst C (trade name "Cure Sol 2PHZ", manufactured by Shikoku Kasei Co., Ltd.). 0.5 parts by mass (manufactured by Kogyo Co., Ltd.) and 6 parts by mass of a visible light-absorbing dark blue dye (trade name "OIL BLACK BS", manufactured by Orient Chemical Industries, Ltd.) were added to methyl ethyl ketone and mixed, and the solid content concentration was A resin composition of 36% by mass was obtained. Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and then punched into a disk shape with a diameter of 315 mm. In the manner described above, a semiconductor back adhesive film (thermosetting semiconductor back adhesive film) of Example 2 having a thickness of 15 μm was produced on a PET separator.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Example 1, and the semiconductor back adhesive film of Example 2 was bonded to the exposed adhesive layer using a laminator to produce the adhesive film with dicing tape of Example 2.

Example 3
(Preparation of laser mark layer)
100 parts by mass of acrylic resin (trade name "Teisan Resin SG-708-6", glass transition temperature: 4°C, manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name "JER YL980", Mitsubishi Chemical Corporation) 29 parts by mass of epoxy resin E ₂ (product name "KI-3000-4", manufactured by Nippon Steel Chemical Co., Ltd.), and 44 parts by mass of epoxy resin E 2 (product name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) ), 206 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.), and thermosetting catalyst E (trade name "TPP", Hokuko Chemical Co., Ltd.) 10 parts by mass (manufactured by OIL BLACK BS) and 13 parts by mass of a visible light-absorbing dark blue dye (trade name "OIL BLACK BS", manufactured by Orient Chemical Industry Co., Ltd.) were added to methyl ethyl ketone and mixed to give a solid content concentration of 36% by mass. A resin composition was obtained. Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, thereby producing a 7 μm thick laser mark layer (thermally cured layer) of Example 3 on the PET separator.

(Preparation of back adhesive layer)
100 parts by mass of acrylic resin (trade name "Teisan Resin SG-708-6", glass transition temperature: 4°C, manufactured by Nagase ChemteX Co., Ltd.) and phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) ) and 254 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.) were added to methyl ethyl ketone and mixed to obtain a solid content concentration of 36% by mass. A resin composition was obtained. Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, thereby producing a back adhesive layer of Example 3 having a thickness of 8 μm on the PET separator.

The laser mark layer on the PET separator produced as described above and the back adhesive layer on the PET separator were bonded together using a laminator. Specifically, the exposed surfaces of the laser mark layer and the back adhesive layer were bonded together under conditions of a temperature of 100° C. and a pressure of 0.6 MPa, and then punched out into a disk shape with a diameter of 315 mm. The back adhesive film of Example 3 was produced as described above.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Example 1, and the laser mark layer surface of the semiconductor back adhesive film of Example 3 was bonded to the exposed adhesive layer using a laminator, and the adhesive film with the dicing tape of Example 3 was attached. Created.

Example 4
(Preparation of back adhesive layer)
100 parts by mass of acrylic resin (trade name "Teisan Resin SG-708-6", glass transition temperature: 4°C, manufactured by Nagase ChemteX Co., Ltd.) and phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) ) and 106 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.) were added to methyl ethyl ketone and mixed to obtain a solid content concentration of 36% by mass. A resin composition was obtained. Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, thereby producing a back adhesive layer of Example 4 having a thickness of 8 μm on the PET separator.

The laser mark layer of Example 3 and the back adhesive layer of Example 4 on the PET separator produced as described above were bonded together using a laminator. Specifically, the exposed surfaces of the laser mark layer and the back adhesive layer were bonded together under conditions of a temperature of 100° C. and a pressure of 0.6 MPa, and then punched out into a disk shape with a diameter of 315 mm. The back adhesive film of Example 4 was produced as described above.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Example 1, and the laser mark layer surface of the semiconductor back adhesive film of Example 4 was bonded to the exposed adhesive layer using a laminator, and the adhesive film with dicing tape of Example 4 was attached. Created.

Example 5
(dicing tape)
Plastic film B (two-layer structure of ionomer base material (20 μm)/polyurethane base material (60 μm), base material thickness: 80 μm) was used as the base material, and the polyurethane base material of the above plastic film B was used on the exposed surface of the adhesive layer. A dicing tape (thickness: 85 μm) of Example 5 was produced in the same manner as Example 1 except that the surfaces were bonded together.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Example 5, and the semiconductor back adhesive film of Example 1 was bonded to the exposed adhesive layer using a laminator to produce the adhesive film with dicing tape of Example 5.

Example 6
(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Example 5, and the laser mark layer surface of the semiconductor back adhesive film of Example 4 was bonded to the exposed adhesive layer using a laminator, and the adhesive film with dicing tape of Example 6 was attached. Created.

Comparative example 1
(dicing tape)
Comparative Example 1 was carried out in the same manner as in Example 1, except that plastic film C (EVA base material, base material thickness: 125 μm) was used as the base material, and the above plastic film C was laminated on the exposed surface of the adhesive layer. A dicing tape (thickness: 130 μm) was produced.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Comparative Example 1, and the semiconductor back adhesive film of Example 1 was bonded to the exposed adhesive layer using a laminator to produce an adhesive film with dicing tape of Comparative Example 1.

Comparative example 2
(Preparation of back adhesive film)
100 parts by mass of acrylic resin (trade name "Teisan Resin SG-708-6", glass transition temperature: 4°C, manufactured by Nagase ChemteX Corporation) and epoxy resin E ₁ (trade name "JER YL980", Mitsubishi Chemical Corporation) 2 parts by mass of epoxy resin E ₂ (trade name "KI-3000-4", manufactured by Nippon Steel Chemical Co., Ltd.), and 3 parts by mass of epoxy resin E 2 (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) ), 92 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.), and thermosetting catalyst C (trade name "Cure Sol 2PHZ", manufactured by Shikoku Kasei Co., Ltd.). 0.4 parts by mass (manufactured by Kogyo Co., Ltd.) and 6 parts by mass of a visible light-absorbing dark blue dye (trade name "OIL BLACK BS", manufactured by Orient Chemical Industries, Ltd.) were added to methyl ethyl ketone and mixed, and the solid content concentration was determined. A resin composition of 36% by mass was obtained. Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and then punched into a disk shape with a diameter of 315 mm. As described above, a semiconductor back adhesive film (thermosetting semiconductor back adhesive film) of Comparative Example 2 having a thickness of 15 μm was produced on a PET separator.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Comparative Example 1, and the semiconductor back adhesive film of Comparative Example 2 was laminated to the exposed adhesive layer using a laminator to produce an adhesive film with dicing tape of Comparative Example 2.

Comparative example 3
(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Comparative Example 1, and the laser mark layer surface of the semiconductor back adhesive film of Example 3 was bonded to the exposed adhesive layer using a laminator, and the adhesive film with dicing tape of Comparative Example 3 was attached. Created.

Comparative example 4
(Preparation of back adhesive layer)
100 parts by mass of acrylic resin (trade name "Teisan Resin SG-708-6", glass transition temperature: 4°C, manufactured by Nagase ChemteX Co., Ltd.) and phenol resin (trade name "MEH7851-SS", manufactured by Meiwa Kasei Co., Ltd.) ) and 95 parts by mass of silica filler (trade name "SO-25R", average particle size: 0.5 μm, manufactured by Admatex Co., Ltd.) were added to methyl ethyl ketone and mixed to obtain a solid content concentration of 36% by mass. A resin composition was obtained. Next, the resin composition was applied using an applicator onto the silicone release-treated surface of a PET separator (thickness: 50 μm) having a silicone release-treated surface to form a resin composition layer. Next, this composition layer was heated at 130° C. for 2 minutes to remove the solvent, and a back adhesive layer of Comparative Example 4 having a thickness of 8 μm was produced on the PET separator.

The laser mark layer of Example 3 and the back adhesive layer of Comparative Example 4 on the PET separator produced as described above were bonded together using a laminator. Specifically, the exposed surfaces of the laser mark layer and the back adhesive layer were bonded together under conditions of a temperature of 100° C. and a pressure of 0.6 MPa, and then punched out into a disk shape with a diameter of 315 mm. A back contact film of Comparative Example 4 was produced as described above.

(Preparation of adhesive film with dicing tape)
The PET separator was peeled off from the dicing tape of Comparative Example 1, and the laser mark layer surface of the semiconductor back adhesive film of Comparative Example 4 was bonded to the exposed adhesive layer using a laminator, and the adhesive film with dicing tape of Comparative Example 4 was attached. Created.

<Evaluation>
The following evaluations were performed on the dicing tapes, semiconductor back adhesive films, and adhesive films with dicing tapes obtained in Examples and Comparative Examples. The results are shown in the table.

(1) Glass transition temperature of adhesive layer Approximately 2 mg of the adhesive layer was scraped off from the dicing tapes prepared in Examples and Comparative Examples to obtain a measurement sample, and the measurement sample was measured using a differential scanning calorimeter "DSCQ2000" (TA Instruments ), the temperature was raised at a heating rate of 2°C/min in the temperature range from -50°C to 50°C, DSC measurements were performed to create a calorific curve, and the inflection point in the calorific curve obtained was was obtained as the glass transition temperature (Tg).

(2) Peeling force of adhesive film against silicone (releasing force against silicone)
Peel off the separator on one side (the side on the laser mark layer side in the case of a two-layer structure) of the adhesive films (semiconductor back adhesive films) obtained in Examples and Comparative Examples, and apply adhesive tape (trade name "BT-315"). (manufactured by Nitto Denko Corporation) were pasted together and cut to a width of 10 mm and a length of 150 mm to obtain a test piece. On the other hand, the mirror side of a 6-inch silicon wafer was wiped with toluene and ethanol, and then placed on a 70° C. hot plate with the mirror side facing up. Then, the adhesive film surface of the test piece (in the case of a two-layer structure, the surface on the back adhesive layer side) was attached to the mirror surface side of the silicon wafer, and left for 2 minutes. The bonding was performed by a crimping operation in which a 2 kg hand roller was moved back and forth once. Thereafter, the stack of silicon wafers and test pieces was removed from the hot plate and air-cooled for 30 minutes until it returned to room temperature. Then, using a tensile testing machine (trade name "Autograph AG-X", manufactured by Shimadzu Corporation), the test piece was subjected to a peel test at 25°C, a peel angle of 180°, and a tensile speed of 300 mm/min. The average value of the values in the range from the start point of 10 mm to the end point of 100 mm from the start of the measurement was obtained as the peeling force of the adhesive film to the silicone.

(3) Amount of fracture push-up Amount obtained in Examples and Comparative Examples was applied to a disc-shaped silicon with a thickness of 500 μm and a diameter of 300 mm that was ground with No. 2000 finish using a wafer mounter "MA3000III" (manufactured by Nitto Seiki Co., Ltd.). The adhesive film surfaces of the adhesive film with dicing tape were bonded together. The bonding was performed under conditions of a table temperature of 70° C. and a bonding pressure of 0.15 MPa. After that, using a die separator (product name "DDS2300", manufactured by DISCO Co., Ltd.), after leaving it for 2 minutes at a temperature of -15°C, the hollow cylindrical shape of the die separator was The push-up member is brought into contact with the dicing tape side of the adhesive film with dicing tape in an area outside the area provided with the disc-shaped silicon and raised, and the dicing tape is stretched in two-dimensional directions including the radial direction and the circumferential direction. It expanded like this. Then, the amount of rise of the push-up member when the dicing tape broke was measured as the amount of push-up at break.

(4) Peeling of Adhesive Film In the evaluation of the amount of push-up at break, the case where the adhesive film did not peel off during expansion was evaluated as ◯, and the case where peeling occurred was evaluated as ×.

1 Adhesive film with dicing tape 10 Dicing tape 11 Base material 12 Adhesive layer 20, 21 Adhesive film 20a Adhesive film (semiconductor back adhesive film)
21a Back adhesive layer 22a Laser mark layer W, 30A, 30C Semiconductor wafer 30B Semiconductor wafer division body 30a Division groove 30b Modified region 31 Semiconductor chip

Claims (5)

A dicing tape having a laminated structure including a base material and an adhesive layer;
an adhesive film that is releasably adhered to the adhesive layer of the dicing tape,
The adhesive film has a peel force of 5 N/10 mm or more in a peel test against silicon at a temperature of 25 ° C. and a peel angle of 180 °,
An adhesive film with a dicing tape having a breaking push-up amount of 10 mm or more as measured by the breaking push-up test described below.
Breaking push-up test: A 500-μm-thick silicon disk is pasted onto an adhesive film, and an expanding device is used to push up a hollow cylindrical member with the silicon disk at a temperature of -15°C and a speed of 400 mm/s. In the area outside the area, the adhesive film with dicing tape is brought into contact with the dicing tape side and raised, and the dicing tape is expanded so as to be stretched in two-dimensional directions including the radial direction and the circumferential direction. Then, the amount of rise of the push-up member when the dicing tape breaks is measured as the break-up push-up amount. The adhesive film with dicing tape according to claim 1, wherein the base material includes a polyurethane base material. 3. The adhesive film with dicing tape according to claim 1, wherein the adhesive layer is a radiation-curable acrylic adhesive layer and has a glass transition temperature of -20°C or lower. The adhesive film with dicing tape according to any one of claims 1 to 3, wherein the total thickness of the base material and the adhesive layer is 80 μm or more. The adhesive film with dicing tape according to any one of claims 1 to 4, wherein the base material has a multilayer structure including a polyurethane base material.

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