Thermal viscosity-reducing adhesive tape for semiconductor cutting and preparation method of thermal viscosity-reducing adhesive tape

Abstract

The thermal viscosity-reducing adhesive tape for semiconductor cutting comprises a release layer and an adhesive layer, the release layer comprises a first release layer and a second release layer, and the first release layer and the second release layer are respectively adhered to two sides of the adhesive layer; the adhesive layer comprises a basic copolymer, a thermal initiator, a curing agent and an auxiliary agent. The method for preparing the thermal-viscosity-reducing adhesive tape for semiconductor cutting comprises the following steps: reacting the stabilizer, the curing agent, the catalyst and methacrylic acid at a constant temperature, and then adding an acetone solvent to obtain a prepolymer; adding lauryl acrylate, bisphenol A epoxy resin, 3, 4-epoxy cyclohexyl formate, styrene, acrylic acid-2-hydroxyethyl ester, a flatting agent and a photoinitiator into the prepolymer to obtain a heat reducing adhesive; and coating the first release layer with the heat-reducing adhesive, covering the surface of the heat-reducing adhesive with the second release layer, and curing to obtain the heat-reducing adhesive tape for semiconductor cutting. The preparation process is simple, the crosslinking degree is high, the prepared adhesive tape has high initial viscous force, and adhesive residues can be reduced after stripping.

Description

Technical field:

[0001] The invention relates to the technical field of adhesive tapes, and in particular to a thermally debonding adhesive tape for semiconductor cutting and a preparation method thereof. Background technology:

[0002] In the semiconductor industry, wafer processing usually includes a series of fine processing processes, such as wafer thinning and wafer cutting. In these processes, the wafer needs to be firmly attached to prevent wafer breakage, surface defects and debris during processing. After the processing is completed, the wafer is required to be safely separated or the chip is easy, quick and quality-preserving to pick up and separate after cutting. The thermal adhesive tape has a certain adhesion at room temperature, which can play a positioning role and meet various precision processing requirements. However, the adhesion will disappear after heating, and it can be easily peeled off. Therefore, the thermal adhesive tape is often used in the field of semiconductor cutting. However, when the existing thermal adhesive tape is used, it will be exposed to ultraviolet light for a long time, and there will be a lot of residual adhesive that cannot be handled after peeling. Summary of the invention:

[0003] The invention designs a heat-reducing adhesive tape for semiconductor cutting and a preparation method thereof to reduce the problem of adhesive residue when the adhesive tape is peeled off.

[0004] A heat-reducing adhesive tape for semiconductor cutting, comprising a release layer and an adhesive layer, wherein the release layer comprises a first release layer and a second release layer, and the first release layer and the second release layer are respectively adhered to the two sides of the adhesive layer; the adhesive layer comprises a basic copolymer, a thermal initiator, a curing agent and an auxiliary agent, and the adhesive layer is mixed in the following proportions by weight: 75-85 parts of the basic copolymer, 0.5-5 parts of the curing agent, 5-15 parts of the thermal initiator, 6-10 parts of the auxiliary agent, and 110-150 parts of the acetone solvent. The components and proportions by weight of the basic copolymer are: 40-55 parts of methacrylic acid, 20-35 parts of lauryl acrylate, 0.5-3 parts of bisphenol A epoxy resin, 3-5 parts of 3,4-epoxycyclohexyl carboxylate, 2-4 parts of styrene, and 0.5-3 parts of 2-hydroxyethyl acrylate; the auxiliary agent comprises a molecular weight regulator, a stabilizer, a leveling agent, and a catalyst.

[0005] Preferably, the curing agent is one or a combination of isophorone diisocyanate and propylene imine; the thermal initiator is one or a combination of dibenzoyl peroxide, azobisisobutyronitrile, azobisisoheptylnitrile.

[0006] Preferably, the molecular weight regulator is isopropanol, the stabilizer is one of copper cyclohexaneate, hydroquinone monomethyl ether, hydroquinone, and p-methoxyphenol, the leveling agent is polyacrylate, and the catalyst is triphenyl bismuth.

[0007] A method for preparing a heat-reducing adhesive tape for semiconductor cutting comprises the following steps:

[0008] 2-3 parts of stabilizer and 0.5-5 parts of curing agent are mixed and put into a flask, heated to 40-70°C while stirring, 0.5-1 parts of catalyst and 40-55 parts of methacrylic acid are added, and the mixture is reacted at a constant temperature for 1-3 hours, and 120-150 parts of acetone solvent are added and reacted for 1-3 hours while stirring to obtain a prepolymer;

[0009] Add 20-35 parts of lauryl acrylate, 0.5-3 parts of bisphenol A epoxy resin, 3-5 parts of 3,4-epoxycyclohexyl carboxylate, 2-4 parts of styrene, 0.5-3 parts of 2-hydroxyethyl acrylate and 1-2 parts of leveling agent to the prepolymer, heat to 40-70° C. while stirring, react for 1-3 hours, add 5-15 parts of photoinitiator, react for 1-3 hours while stirring, cool naturally to room temperature after the reaction, shake to remove bubbles, and obtain a thermal viscosity-reducing adhesive for semiconductor cutting;

[0010] The thermal de-viscosity adhesive is evenly coated on the first release layer of 12 to 20 μm, and the second release layer is covered on the surface of the thermal de-viscosity adhesive, and after drying and curing, the thermal de-viscosity adhesive tape for semiconductor cutting is obtained. Generally, the production and coating process are carried out in a dust-free workshop of Class 1000 or above.

[0011] Preferably, the first release layer and the second release layer are both PET films.

[0012] The invention discloses a heat-reducing adhesive tape for semiconductor cutting and a preparation method thereof. The adhesive of the heat-reducing adhesive tape is prepared by a "one-pot method", the preparation process is simple, the production efficiency is high, and the preparation method has the possibility of industrialization; at the same time, the multifunctional polymer added to the adhesive of the heat-reducing adhesive tape disclosed by the method contains a large number of polymer groups, which can form a polymer network structure after the adhesive is photocured, and the cross-linking degree is high, and the adhesive residue can be reduced after peeling; at the same time, the adhesive tape prepared by the invention has a viscosity of 5-10 Newtons before illumination, has a high initial viscosity, and the viscosity decays rapidly to about 0.1 Newton after illumination, and is easy to peel after illumination. Specific implementation method:

[0013] The following describes a method for preparing a heat-reducing adhesive tape for semiconductor cutting provided by the present invention in combination with specific embodiments.

[0014] Embodiment 1:

[0015] Mix 2 g of hydroquinone monomethyl ether and 0.5 g of isophorone diisocyanate and put them into a four-necked flask; heat to 40°C while stirring, add 0.5 g of triphenyl bismuth at the same time, and age at 40°C for 1 hour; after aging, add 120 g of acetone, stir evenly, and age at 40°C for 1 hour to obtain a prepolymer.

[0016] 20 g of lauryl acrylate, 0.5 g of bisphenol A epoxy resin, 3 g of 3,4-epoxycyclohexyl carboxylate, 2 g of styrene, 0.5 g of 2-hydroxyethyl acrylate and 1 g of polyacrylate are added to the prepolymer, heated to 40° C. while stirring, reacted for 1 h, 5 g of dibenzoyl peroxide is added, stirred and reacted for 1 h, cooled naturally to room temperature after the reaction is completed, shaken to remove bubbles, and a thermal viscosity-reducing adhesive for semiconductor cutting is obtained;

[0017] The thermal de-viscosity adhesive is evenly coated on the first release layer with a thickness of 15 μm, and the second release layer is covered on the surface of the thermal de-viscosity adhesive. After drying and curing, the thermal de-viscosity adhesive tape for semiconductor cutting is obtained.

[0018] The initial adhesion of the thermally debonding tape for semiconductor dicing prepared in this embodiment is 5 Newtons; after exposure to light, the adhesion decays to 0.4 Newtons.

[0019] Embodiment 2:

[0020] Mix 2.5 g of hydroquinone monomethyl ether and 2.5 g of isophorone diisocyanate and put them into a four-necked flask; heat to 55°C while stirring, add 0.75 g of triphenyl bismuth at the same time, and age at 55°C for 2 hours; after aging, add 135 g of acetone, stir evenly, and age at 55°C for 2 hours to obtain a prepolymer.

[0021] 25 g of lauryl acrylate, 2.5 g of bisphenol A epoxy resin, 4 g of 3,4-epoxycyclohexyl carboxylate, 3 g of styrene, 2 g of 2-hydroxyethyl acrylate and 1.5 g of polyacrylate are added to the prepolymer, heated to 55° C. while stirring, reacted for 2 h, 10 g of dibenzoyl peroxide is added, stirred and reacted for 2 h, cooled naturally to room temperature after the reaction is completed, shaken to remove bubbles, and a thermal viscosity-reducing adhesive for semiconductor cutting is obtained;

[0022] The thermal de-viscosity adhesive is evenly coated on the first release layer with a thickness of 12 μm, and the second release layer is covered on the surface of the thermal de-viscosity adhesive. After drying and curing, the thermal de-viscosity adhesive tape for semiconductor cutting is obtained.

[0023] The initial adhesion of the thermally debonding tape for semiconductor dicing prepared in this embodiment is 10 Newtons; after exposure to light, the adhesion decays to 0.1 Newton.

[0024] Embodiment 3:

[0025] Mix 3g of hydroquinone monomethyl ether and 5g of isophorone diisocyanate and put them into a four-necked flask; heat to 70°C while stirring, add 1g of triphenylbismuth at the same time, and age at 70°C for 3h; after aging, add 150g of acetone, stir evenly, and age at 70°C for 3h to obtain a prepolymer.

[0026] 35g of lauryl acrylate, 3g of bisphenol A epoxy resin, 5g of 3,4-epoxycyclohexyl carboxylate, 4g of styrene, 3g of 2-hydroxyethyl acrylate and 2g of polyacrylate are added to the prepolymer, heated to 70°C while stirring, reacted for 3h, 15g of dibenzoyl peroxide is added, stirred and reacted for 3h, cooled naturally to room temperature after the reaction is completed, shaken to remove bubbles, and a thermal viscosity-reducing adhesive for semiconductor cutting is obtained;

[0027] The thermal de-viscosity adhesive is evenly coated on the first release layer of 20 μm, and the second release layer is covered on the surface of the thermal de-viscosity adhesive. After drying and curing, the thermal de-viscosity adhesive tape for semiconductor cutting is obtained.

[0028] The initial adhesion of the thermally debonding tape for semiconductor dicing prepared in this embodiment is 7 Newtons; after exposure to light, the adhesion decays to 0.3 Newton.

[0029] The above description is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements, substitutions, modifications and embellishments can be made without departing from the principle and purpose of the present invention. These improvements, substitutions, modifications and embellishments should also be regarded as the scope of protection of the present invention.

Claims

1. A heat-reducing adhesive tape for semiconductor cutting, characterized in that: The invention comprises a release layer and an adhesive layer, wherein the release layer comprises a first release layer and a second release layer, and the first release layer and the second release layer are respectively adhered to the two sides of the adhesive layer; the adhesive layer comprises a basic copolymer, a thermal initiator, a curing agent and an auxiliary agent, and the adhesive layer comprises the following proportions in parts by weight: 75-85 parts of the basic copolymer, 0.5-5 parts of the curing agent, 5-15 parts of the thermal initiator, 6-10 parts of the auxiliary agent, and 110-150 parts of the acetone solvent, wherein the components of the basic copolymer and the proportions in parts by weight are: 40-55 parts of methacrylic acid, 20-35 parts of lauryl acrylate, 0.5-3 parts of bisphenol A epoxy resin, 3-5 parts of 3,4-epoxycyclohexylcarboxylate, 2-4 parts of styrene, and 0.5-3 parts of 2-hydroxyethyl acrylate; the auxiliary agent comprises a molecular weight regulator, a stabilizer, a leveling agent, and a catalyst.

2. The heat-reducing adhesive tape for semiconductor dicing according to claim 1, characterized in that: The curing agent is one or a combination of isophorone diisocyanate and propylene imine; the thermal initiator is one or a combination of dibenzoyl peroxide, azobisisobutyronitrile, and azobisisoheptylnitrile.

3. The heat-reducing adhesive tape for semiconductor dicing according to claim 1, characterized in that: The molecular weight regulator is isopropanol, the stabilizer is one of copper cyclohexaneate, hydroquinone monomethyl ether, hydroquinone, and p-methoxyphenol, the leveling agent is polyacrylate, and the catalyst is triphenyl bismuth.

4. A method for preparing a heat-reducing adhesive tape for semiconductor cutting, characterized in that: The method comprises the following steps: 2-3 parts of stabilizer and 0.5-5 parts of curing agent are mixed and put into a flask, heated to 40-70°C while stirring, 0.5-1 parts of catalyst and 40-55 parts of methacrylic acid are added, and the mixture is reacted at a constant temperature for 1-3 hours, and 120-150 parts of acetone solvent are added and reacted for 1-3 hours while stirring to obtain a prepolymer; Add 20-35 parts of lauryl acrylate, 0.5-3 parts of bisphenol A epoxy resin, 3-5 parts of 3,4-epoxycyclohexyl carboxylate, 2-4 parts of styrene, 0.5-3 parts of 2-hydroxyethyl acrylate and 1-2 parts of leveling agent to the prepolymer, heat to 40-70° C. while stirring, react for 1-3 hours, add 5-15 parts of photoinitiator, react for 1-3 hours while stirring, cool naturally to room temperature after the reaction, shake to remove bubbles, and obtain a thermal viscosity-reducing adhesive for semiconductor cutting; The thermal de-viscosity adhesive is evenly coated on the first release layer of 12 to 20 μm, and the second release layer is covered on the surface of the thermal de-viscosity adhesive. After drying and curing, the thermal de-viscosity adhesive tape for semiconductor cutting is obtained.

5. The method for preparing a heat-reducing adhesive tape for semiconductor dicing according to claim 4, characterized in that: The first release layer and the second release layer are both PET films.