JPH10150007A - Semiconductor wafer fixing sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily remove a chip at the time of picking it up by using pressure sensitive adhesives whose adhesive strength is respectively reduced only by different adhesive strength reducing means for a pressure sensitive adhesive layer for fixing a semiconductor wafer and a pressure sensitive adhesive layer for fixing the position. SOLUTION: A major part is composed of a semiconductor wafer fixing pressure sensitive adhesive layer 2 composed of thermosetting pressure sensitive adhesive laminated on one plane of a supporting body 1 and a sheet fixing pressure sensitive adhesive layer 3 composed of UV hardening pressure sensitive adhesive laminated on the other plane. The supporting body 1 is formed of polyethyleneterephthalate. The pressure sensitive adhesive layer 2 is formed of thermosetting pressure sensitive adhesive, and the pressure sensitive adhesive layer 3 is formed of UV hardening pressure sensitive adhesive. Thus, semiconductor chips can be removed from the semiconductor wafer fixing sheet after dicing without scattering them.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor wafer fixing method in which a pressure-sensitive adhesive layer is laminated on both sides, a plate-like semiconductor wafer is held by one pressure-sensitive adhesive layer, and the other pressure-sensitive adhesive layer is adhered to a fixing table. Regarding the sheet.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 2, a sheet for fixing a semiconductor wafer has a structure in which adhesive layers A and B are laminated on both sides of a sheet-like support S. The plate-shaped semiconductor wafer H is held by the pressure-sensitive adhesive layer A, and is stably fixed to the fixing table D by the other sheet-fixing pressure-sensitive adhesive layer B. The fixing table D is a part of a dicing apparatus for dicing the semiconductor wafer H into chips, and the position of the fixing table D must be extremely precise.

Here, an adhesive layer A for fixing a semiconductor wafer is used.
Must be firmly adhered to the semiconductor wafer H at the time of dicing, and must be easily detached when picking up the chip of the semiconductor wafer H. The sheet fixing pressure-sensitive adhesive layer B has an adhesive force for maintaining the position of the semiconductor wafer H even when subjected to an impact during dicing, but can be separated from the fixing table D after dicing as shown in FIG. There must be.

Accordingly, the semiconductor wafer fixing sheet needs to have a high adhesive force at the time of dicing, while having a low adhesive force at the time of peeling from the fixing table and at the time of picking up.

In response to such a demand, the present applicant has disclosed a semiconductor wafer fixing sheet capable of reducing the adhesive force during dicing by heating or ultraviolet irradiation (Japanese Patent Application No. 8-170624, 8-19840
No. 2).

[0006]

However, when the semiconductor fixing sheet is to be peeled off from the fixing stand of the pick-up apparatus by lowering the adhesive force of the position fixing pressure-sensitive adhesive layer, the semiconductor which has become a chip is removed from the sheet. There was a problem of being separated. This is because the adhesive force of the semiconductor wafer fixing adhesive was also reduced when the adhesive force of the sheet fixing adhesive layer was reduced by heating or irradiation with ultraviolet rays.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a semiconductor wafer fixing device which can be detached from a fixing table without detaching the chip even if it is subjected to an adhesive force reducing means after dicing, and which can easily detach the chip at the time of chip pick-up. To provide a seat.

[0008]

The inventor of the present invention has conducted intensive studies in view of the above, and as a result, has found that the adhesive strength of the adhesive layer for fixing the semiconductor wafer and the adhesive layer for fixing the position can be reduced only by separate adhesive force reducing means. It has been found that the above problem can be solved by employing a pressure-sensitive adhesive that does not lower the pressure, and the present invention has been completed.

That is, the semiconductor wafer fixing sheet according to the present invention comprises a sheet-like support, a semiconductor wafer fixing adhesive layer laminated on one surface of the support, and the other surface of the support. In the semiconductor wafer fixing sheet whose main part is constituted by the sheet fixing pressure-sensitive adhesive layer laminated on one of the above, one of the semiconductor wafer fixing pressure-sensitive adhesive layer or the sheet fixing pressure-sensitive adhesive layer is formed of a heat-curable pressure-sensitive adhesive. The other is made of an ultraviolet-curable pressure-sensitive adhesive.

Here, one of the adhesive layers is made of a heat-curable type and the other is made of an ultraviolet-curable type because only the adhesive force of the adhesive for fixing the sheet is reduced and then the adhesive for fixing the semiconductor wafer is reduced. This is to reduce the adhesive strength of the agent.

As the heat-curable pressure-sensitive adhesive and the ultraviolet-curable pressure-sensitive adhesive in the present invention, conventionally known various ones can be employed.
In addition, these compounds exhibit a tackiness with a base polymer, which is a main ingredient, and reduce the tackiness with an oligomer and / or a monomer. A heat polymerization initiator is compounded as an initiator for decreasing the tackiness. If this is done, it becomes a heat-curable pressure-sensitive adhesive, and if an ultraviolet-ray polymerization initiator is blended, it becomes a UV-curable pressure-sensitive adhesive.

Here, the adhesive strength of the UV-curable pressure-sensitive adhesive and the heat-curable pressure-sensitive adhesive is reduced by the heat polymerization initiator which has been subjected to a heat treatment at 70 to 150 ° C. or the ultraviolet polymerization initiator which has received the ultraviolet ray. This is because the entire adhesive becomes a three-dimensional network structure and is cured.

As a specific value of the adhesive strength, the 180-degree peel adhesive strength (JIS Z 0237) in the range of 100 to 3000 gf / 20 mm (peeling speed 300 mm / min) before heating or irradiation with ultraviolet light is obtained by heating. Or, after ultraviolet irradiation, 0 to 50 gf / 20 mm (peeling speed 300 mm /
Min). In order to set the adhesive force of the UV-curable adhesive to such a value, the base polymer 1
It is preferable that the main components are 00 parts by weight, 5 to 900 parts by weight of an oligomer and / or a monomer, and 0.1 to 5 parts by weight of an ultraviolet polymerization initiator. Preferably, the main component is 100 parts by weight of a base polymer, 5 to 900 parts by weight of an oligomer and / or a monomer, and 0.1 to 10 parts by weight of a heat polymerization initiator.

The heating means as the means for reducing the adhesive strength can be appropriately adopted as long as the semiconductor wafer fixing sheet can be heated to 70 to 150 ° C., and is not particularly limited. Examples thereof include an oven, a hot air heater, and an electric heater. There are heaters and the like. Further, as the ultraviolet irradiation means, a conventionally known ultraviolet irradiation apparatus can be adopted.

Here, as the above-mentioned heat polymerization initiator of the compounding member which is a feature of the present invention, the above-mentioned oligomer and / or monomer is cured by being heated to cure the entire pressure-sensitive adhesive, thereby obtaining the adhesive strength. If the compounding ratio is too large, the composition becomes too sensitive to heat and cures due to a change in environmental temperature, resulting in poor storage stability. Further, a drying step (100 ° C., 1 minute) ) Alone, it is impossible to obtain the required quality as a product. If the amount is too small, the curing is slow and the workability is inferior, so that preferably 0.1 to 10 parts by weight, more preferably 0.5 to 5 parts by weight. Good.

As the heat polymerization initiator, there are an organic peroxide derivative and an azo-based polymerization initiator. The azo-based polymerization initiator is more preferably an organic peroxide derivative because nitrogen is generated during heating. Specific examples of the heat polymerization initiator include ketone peroxide, peroxyketal, hydroperoxide, dialkyl peroxide, diacyl peroxide, peroxyester, peroxydicarbonate, and azobisisobutyronitrile. is there. If necessary, an amine compound such as triethylamine, tetraethylpentamine, or dimethylaminoether may be used in combination as a polymerization accelerator.

The ultraviolet polymerization initiator is used for curing the oligomer and / or monomer when irradiated with ultraviolet light, thereby curing the entire pressure-sensitive adhesive and reducing its adhesive strength. If the compounding ratio is too large, it is sensitive to light and storage stability deteriorates, and if it is too small, curing is slow and workability is inferior, so that preferably 0.1 to 5 parts by weight, more preferably 1 to 3 parts by weight is used. Good.

Specific examples of the ultraviolet polymerization initiator include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzyl diphenyl sulfide, tetramethyl thiuram monosulfide, azobisisobutyronitrile, dibenzyl , Diacetyl, β-chloranthraquinone and the like. In addition, an amine compound such as triethylamine, tetraethylpentamine, or dimethylaminoether may be used as a photopolymerization accelerator, if necessary, as the ultraviolet polymerization initiator.

Unintentional polymerization (for example, polymerization by heat) by blending a polymerization inhibitor with the ultraviolet polymerization initiator.
Can also be prevented. As this polymerization inhibitor,
Examples include picric acid, phenol, hydroquinone, and hydroquinone monomethyl ether.

The oligomer and / or monomer according to the present invention includes a photopolymerizable carbon-carbon dimer in a molecule which can be three-dimensionally networked by a heated polymerization initiator or an ultraviolet polymerization initiator irradiated with ultraviolet rays. There are low molecular weight compounds having at least two or more heavy bonds, and specific examples include acrylate compounds and urethane acrylate oligomers. By forming the oligomer and / or monomer into a three-dimensional network, the entire pressure-sensitive adhesive can be cured and the adhesive strength can be reduced.

In the present invention, if the compounding ratio of the oligomer and / or the monomer is too large, the compound becomes sensitive to heat and light, is cured by environmental temperature and ordinary light, and has poor storage stability. It hardens only in the process (100 ° C, 1 minute), and the required quality as a product cannot be obtained.
On the other hand, if the amount is too small, the curing will be slow and the efficiency of lowering the adhesive force will be poor, so the amount is preferably 5 to 900 parts by weight, more preferably 20 to 200 parts by weight.

The acrylate compounds include, for example, trimethylolpropane triacrylate, tetramethylol methane tetraacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol monohydroxypentaacrylate, dipentaerythritol hexaacrylate or 1,4 -Butylene glycol diacrylate, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, oligoester acrylate and the like.

On the other hand, the urethane acrylate oligomer is a heat and / or ultraviolet curable compound having at least two carbon-carbon double bonds, for example, a polyester compound or a polyether type polyol compound,
Polyvalent isocyanate compounds such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate,
An isocyanate-terminated urethane prepolymer obtained by reacting 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane 4,4-diisocyanate, or the like, has an acrylate or methacrylate having a hydroxyl group, for example. Examples include those obtained by reacting 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, polyethylene glycol acrylate, polyethylene glycol methacrylate, and the like.

When the urethane acrylate oligomer is employed, the molecular weight is particularly preferably 300 to 30,000,
When the adhesive having a thickness of preferably 1,000 to 8000 is used for the pressure-sensitive adhesive layer for fixing the semiconductor wafer, the pressure-sensitive adhesive does not adhere to the chip at the time of picking up the chip even if the surface of the semiconductor wafer is rough. The adhesive does not remain on the fixed base.

As the base polymer in the present invention, generally known acrylic adhesives, rubber adhesives and the like can be used.

As the acrylic pressure-sensitive adhesive, a conventionally known acrylic pressure-sensitive adhesive can be appropriately selected and used. Generally, a homopolymer (main monomer) having an acrylate ester as a main constituent monomer unit can be used. ) And copolymers with comonomers, copolymers with other functional monomers (functional group-containing monomers), and mixtures of these polymers. Here, examples of the main monomer include ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate. Examples of the comonomer include vinyl acetate, acrylonitrile, acrylamide, styrene,
Examples include methyl methacrylate and methyl acrylate.
Further, as the functional group-containing monomer, methacrylic acid,
Examples include acrylic acid, itaconic acid, hydroxyethyl methacrylate, hydroxypropyl methacrylate, dimethylaminoethyl methacrylate, acrylamide, methylol acrylamide, glycidyl methacrylate, and maleic anhydride.

Examples of the rubber-based pressure-sensitive adhesive include natural rubber, synthetic isoprene rubber, styrene-butadiene rubber,
Styrene / butadiene block copolymer, styrene / isoprene block copolymer, butyl rubber, polyisobutylene, polybutadiene, polyvinyl ether, silicone rubber, polyvinyl isobutyl ether, chloroprene rubber, nitrile rubber, kraft rubber, recycled rubber, styrene / ethylene / butylene -Block copolymer, styrene-propylene-butylene-block copolymer, styrene-isoprene-block polymer, acrylonitrile-butadiene copolymer, acrylonitrile-acryl ester copolymer, methyl methacrylate-butadiene copolymer, polyisobutylene-ethylene Propylene copolymer, ethylene vinyl acetate copolymer, polyisobutylene / silicone rubber, polyvinyl isobutyl ether / chloroprene, etc. It may be a mixture not only these alone product.

Further, it is preferable to add a tackifier resin to the rubber-based pressure-sensitive adhesive in order to increase the adhesion. As the tackifying resin, if the amount is too small, the adhesive effect of the adhesive containing an elastomer as a main component does not appear, and if the amount is too large, the adhesive becomes too soft and the adhesive force does not decrease even when heated or irradiated with ultraviolet rays. It is preferable to mix 5 to 100 parts by weight with respect to 100 parts by weight of a rubber-based adhesive.
It is more preferable to mix 10 to 30 parts by weight.

As the tackifying resin, a rosin resin,
Terpene resin, aliphatic petroleum resin, aromatic petroleum resin, hydrogenated petroleum resin, chroman / indene resin, styrene resin, alkylphenol resin, xylene resin, etc. In consideration of the above, a terpene resin is preferable. Examples of the rosin-based resin include rosin, polymerized rosin, hydrogenated rosin, rosin ester, hydrogenated rosin ester, rosin-modified phenol resin, and the like, and as the terpene resin, a terpene resin,
There are terpene phenol resins, aromatic modified terpene resins, rosin phenol resins and the like. Examples of the hydrogenated petroleum resin include aromatic ones, dicyclopentadiene-based ones, and aliphatic ones.

A curing agent may be added to the pressure-sensitive adhesive layer for fixing a semiconductor wafer or the pressure-sensitive adhesive layer for fixing a sheet, if necessary, in order to arbitrarily set an initial pressure-sensitive adhesive strength.
Adoption of the curing agent enhances cohesive strength as an adhesive, and causes contamination during lamination even before ultraviolet irradiation (unirradiated) (when the sheet once adhered is peeled off, the adhesive of the sheet becomes sticky). (A state remaining on the member) does not occur, and removability can be obtained. If the amount of the curing agent is too small, the anti-contamination function cannot be exerted.If the amount is too large, the initial adhesive strength is lowered, and the chip flies or peels off from the fixing table at the time of dicing. -30 parts by weight, preferably 1.0-5.0 parts by weight.

When the above-mentioned curing agent is used for the adhesive layer for fixing the semiconductor wafer and an elastomer is used as the base polymer, the molecular skeleton of the elastomer itself is softened even if the adhesive force is reduced by heating or irradiation of ultraviolet rays. As a result, the adhesive does not move to the fixing base. Further, when the curing agent is used for the sheet fixing pressure-sensitive adhesive layer and an elastomer is used as the base polymer, the molecular skeleton of the elastomer is firmly adhered to the semiconductor wafer due to the softness, and the chips are not scattered during dicing. Dicing can be performed stably. In addition, damage to the blade due to chip scattering is eliminated, and the durability of the blade is improved, leading to an improvement in productivity.

Examples of the curing agent include isocyanate-based, epoxy-based, and aziridine-based curing agents.
These may be used alone or as a mixture. As the isocyanate, a polyvalent isocyanate compound,
For example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylene diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane- 2,4'-diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicycloxysylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4 '-Diisocyanate, lysine isocyanate, phenylene diisocyanate, tolylene diisocyanate, diphenyl metadiisocyanate, cyclohexane diisocyanate and the like.

The pressure-sensitive adhesive laminated on the semiconductor fixing sheet according to the present invention is generally formed to have a thickness of 5 to 70 μm. This is because if it is too thick, curing by heating or irradiation with ultraviolet rays is delayed, and if it is too thin, the adhesive strength cannot be set high. In addition, conventionally known fillers, antioxidants, softeners, stabilizers, coloring agents, and the like can be appropriately selected and added to the pressure-sensitive adhesive.

As the sheet-like support in the present invention, various synthetic resin materials can be generally used. When the above-mentioned ultraviolet-curable pressure-sensitive adhesive is laminated on the semiconductor wafer fixed side, the support is made to transmit ultraviolet light. It is preferable to use a sheet that allows ultraviolet rays to reach the adhesive. Examples of the material of the support include a single layer or a plurality of layers of polyvinyl chloride, polybutene, polybutadiene, polyurethane, ethylene-vinyl acetate copolymer, polyethylene terephthalate, polyethylene, polypropylene and the like. The thickness of the support is generally selected from the range of 10 to 500 μm.

The semiconductor wafer fixing sheet according to the present invention is stored by adhering release paper or a release sheet such as polyethylene laminated paper or release treated plastic film onto an adhesive as required.

[0036]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A semiconductor wafer fixing sheet according to the present invention comprises a sheet-like support, a semiconductor wafer fixing adhesive layer laminated on one surface of the support, and the other of the support. In the semiconductor wafer fixing sheet whose main part is constituted by the sheet fixing adhesive layer laminated on the surface, one of the semiconductor wafer fixing adhesive layer and the sheet fixing adhesive layer is heat-curable. It is characterized in that the adhesive is an adhesive and the other is an ultraviolet-curing adhesive, whereby the semiconductor wafer fixing sheet can be peeled off without scattering the semiconductor wafer chip after dicing when the fixing base is peeled off, and the semiconductor wafer chip is picked up. Then, the chip can be easily picked up.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments and comparative examples of a semiconductor wafer fixing sheet according to the present invention will be described in detail with reference to the drawings and tables. FIG. 1 is an explanatory view schematically showing a semiconductor wafer fixing sheet of each of Examples and Comparative Examples, and shows a state after dicing a semiconductor wafer fixed by an adhesive force into dice. Table 1 shows the compositions which are the characteristics of the pressure-sensitive adhesive layers of Examples and Comparative Examples, and their characteristic values. The values of the compounds in Table 1 are parts by weight, and the pick-up properties in the characteristic values are as follows: those that were able to pick up the chips after heating or irradiation with ultraviolet light were evaluated as 、; When the semiconductor wafer fixing sheet was peeled off from the fixing table D, the semiconductor wafer chips H diced when the semiconductor wafer chips H were not dropped were not evaluated as ○, and the semiconductor wafer chips H that were dropped were evaluated as ×.

[0038]

[Table 1]

As shown in FIG. 1, the semiconductor wafer fixing sheet according to the first embodiment is a semiconductor wafer comprising a sheet-like support 1 and a heat-curable pressure-sensitive adhesive laminated on one surface of the support 1. The main part is composed of a fixing pressure-sensitive adhesive layer 2 and a sheet fixing pressure-sensitive adhesive layer 3 made of an ultraviolet-curable pressure-sensitive adhesive laminated on the other surface of the support 1. The characteristic composition of each of the pressure-sensitive adhesive layers 2 and 3 is shown in the first example of Table 1.
In the drawings, reference symbol H denotes a semiconductor wafer diced into chips, and D denotes a dicing device (not shown).
It is a fixed base.

The oligomer in Table 1 is Beam Set 575 manufactured by Arakawa Chemical Industry Co., Ltd. The heat-polymerizable initiator is Parloyl T manufactured by NOF Corporation as peroxydicarbonate.
CP and the UV polymerization initiator is Irgacure 651 manufactured by Ciba Geigy.

Although not shown in the table, each adhesive in each of Examples and Comparative Examples contained 100 parts by weight of a base polymer (Nipol AR53L manufactured by Zeon Corporation as an acrylic rubber) as a main agent. 20 parts by weight of a tackifier resin (YS Resin 1250 manufactured by Yasuhara Chemical Co., Ltd. as a terpene resin), and 0.01 part by weight of a thermal polymerization inhibitor (hydroquinone monomethyl ether) when a heat polymerization initiator is added. When an ultraviolet polymerization initiator is added, 3 parts by weight of a curing agent (Coronate L manufactured by Nippon Polyurethane Industry Co., Ltd. as an isocyanate-based curing agent) is added. The support 1 used was polyethylene terephthalate.

In the first embodiment, the chip-shaped semiconductor wafer H did not fall off even if the semiconductor wafer fixing sheet was peeled off from the fixing table D after being irradiated with ultraviolet rays. Further, in the case of the pick-up of chip H, the chip could be picked up without any problem by heating the whole sheet after the peeling and before the pick-up.

Comparative Example 1 shows a composition in which the same ultraviolet curable adhesive as in the first embodiment was used for each of the semiconductor wafer fixing adhesive layer 2 and the sheet fixing adhesive layer 3. In Comparative Example 1, the semiconductor wafer fixing sheet is
When peeled off from the fixing table D after the entire irradiation with ultraviolet rays, a wide range of chips H was scattered at the time of the peeling.

Next, a second embodiment will be described. This embodiment is different from the first embodiment in that the pressure-sensitive adhesive layer 2 for fixing a semiconductor wafer is used.
And a sheet for fixing a semiconductor wafer, wherein the composition of the pressure-sensitive adhesive layer 3 for sheet fixing was changed and laminated, and the support 1 used was polyethylene terephthalate having ultraviolet transmittance.

In the second embodiment, the semiconductor wafer chip H did not fall off even when the semiconductor wafer fixing sheet was heated and peeled off from the fixing table D after heating. Further, in the pick-up of the chip H, the chip H could be picked up without any problem by irradiating the whole sheet with ultraviolet rays after the peeling and before the pick-up.

Comparative Example 2 shows a composition in which the same heat-curable pressure-sensitive adhesive as in the second embodiment was used for each of the pressure-sensitive adhesive layer 2 for fixing the semiconductor wafer and the pressure-sensitive adhesive layer 3 for fixing the sheet. In Comparative Example 2, when the semiconductor wafer fixing sheet was peeled off from the fixing table D after being heated together with the chip H, a wide range of chips H scattered during the peeling.

Next, the structure of the first embodiment (the support 1 is made of polyethylene terephthalate, the semiconductor wafer fixing adhesive layer 2 is made of a heat-curable adhesive, and the sheet fixing adhesive layer 3 is made of an ultraviolet-curable adhesive). A comparative example in which the composition of the adhesive is appropriately changed based on the formed semiconductor wafer fixing sheet) will be described in detail with reference to Table 1.

Comparative examples 3 and 4 show examples in which the composition of the ultraviolet-curable pressure-sensitive adhesive was appropriately changed. In Comparative Example 3 in which the blending ratio of the oligomer was reduced and in Comparative Example 4 in which the blending ratio of the ultraviolet polymerization initiator was reduced, the curing rate of the pressure-sensitive adhesive layer 2 for fixing the semiconductor wafer was slow.
Even after peeling off from the fixing table D after irradiation with ultraviolet rays, a wide range of chips H was scattered at the time of peeling. Although not shown in the table, when the mixing ratio of the oligomer and / or the UV polymerization initiator is more than 300 parts by weight and 5 parts by weight, respectively, there is no problem in a state immediately after laminating the ultraviolet curable adhesive. When light is received after lamination, the ultraviolet-curable pressure-sensitive adhesive is automatically cured, so that only products having poor storage stability can be obtained.

Comparative Examples 5 and 6 show examples in which the composition of the heat-curable pressure-sensitive adhesive was appropriately changed. Comparative Example 5 in which only the blending ratio of the oligomer was reduced, and Comparative Example 6 in which only the blending ratio of the heat-polymerizable initiator was reduced, both of which were inferior in thermosetting properties and had high adhesive strength even after heating and poor pick-up properties. . Although not shown in the table, if the mixing ratio of the oligomer and the heat-polymerizable initiator is more than 900 parts by weight and 10 parts by weight, respectively, the thermal polymerization occurs in the drying step (100 ° C., 1 minute) during the production. As a result, the required quality as a product could not be satisfied.

[0050]

The semiconductor wafer fixing sheet according to the present invention comprises a sheet-like support, a semiconductor wafer fixing adhesive layer laminated on one surface of the support, and the other surface of the support. In the semiconductor wafer fixing sheet whose main part is constituted by the sheet fixing adhesive layer laminated on the substrate, one of the semiconductor wafer fixing adhesive layer and the sheet fixing adhesive layer is a thermosetting adhesive. The other is an ultraviolet-curing adhesive, whereby the semiconductor wafer fixing sheet can be peeled without scattering the semiconductor wafer chip after the dicing when the fixing base is peeled off, and further, when the semiconductor wafer chip is picked up. In this case, the chip can be easily picked up.

[Brief description of the drawings]

FIG. 1 is an explanatory view schematically showing an example of a semiconductor wafer fixing sheet according to the present invention and a comparative example thereof.

FIG. 2 is an explanatory view schematically showing a conventional semiconductor wafer fixing sheet.

[Description of Signs] 1 support 2 adhesive layer for fixing semiconductor wafer 3 adhesive layer for fixing sheet

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takashi Hayashi 2-13-1, Dai, Kamakura-shi, Kanagawa Toyo Kagaku Co., Ltd.

Claims (4)

[Claims] 1. A sheet-shaped support (1), a semiconductor wafer fixing adhesive layer (2) laminated on one surface of the support (1), and the other of the support (1) A semiconductor wafer fixing adhesive layer (2) or a sheet fixing adhesive layer (3), the main part of which is constituted by the sheet fixing adhesive layer (3) laminated on the surface.
Wherein one of the two is a heat-curable adhesive and the other is an ultraviolet-curable adhesive. 2. The heat-curable pressure-sensitive adhesive comprises 100 parts by weight of a base polymer, oligomers and / or monomers 5
2. The semiconductor wafer fixing sheet according to claim 1, wherein the main component is 900 parts by weight and 0.1 to 10 parts by weight of a thermal polymerization initiator. 3. The UV-curable pressure-sensitive adhesive according to claim 1, wherein the UV-curable pressure-sensitive adhesive comprises 100 parts by weight of a base polymer, oligomers and / or monomers 5 to 900.
The semiconductor wafer fixing sheet according to claim 1, wherein the main component is 0.1 parts by weight or 5 to 5 parts by weight of an ultraviolet polymerization initiator. 4. The semiconductor wafer fixing sheet according to claim 2, wherein the oligomer and / or monomer is a urethane acrylate-based oligomer.