TW202035620A - Adhesive tape and manufacturing method of semiconductor package - Google Patents

Abstract

A subject of the disclosure is to provide an adhesive tape and a manufacturing method of a semiconductor package using the adhesive tape, wherein the adhesive tape can be peeled cleanly from a lead frame without leaving a part of an adhesive layer and can prevent mold flash. The subject can be solved by an adhesive tape for use in a manufacturing method of a semiconductor package, wherein the adhesive tape includes a substrate and an adhesive layer disposed on the substrate, and the adhesive layer includes a non-aromatic acrylic polymer that is crosslinked by a metal chelate crosslinking agent.

Description

Adhesive tape and manufacturing method of semiconductor package

The invention relates to an adhesive tape used in a manufacturing method of a semiconductor package and a manufacturing method of the semiconductor package.

Semiconductor packages such as Quad Flat No Lead (QFN) and Small Outline No Lead (SON) are manufactured by sealing and fixing the surface of a lead frame with a semiconductor chip with resin. However, there may be a problem (so-called molding flash) that resin leaks to the back through the opening of the lead frame to cover the terminals of the semiconductor package during sealing. In response to this problem, Patent Document 1 describes "a heat-resistant adhesive tape characterized by including at least: a base layer composed of a polyimide material, and a storage elastic coefficient of 1.0×10 ⁵ Pa at 200°C. A method of attaching the above-mentioned acrylic material with a thickness of 1 μm to 20 μm to the back surface of the lead frame.

However, the adhesive tape is modified by the plasma treatment performed during the manufacturing process of the semiconductor package, and sometimes it may not be completely peeled off from the lead frame and a part of it may remain. In response to this problem, Patent Document 2 describes the use of "a heat-resistant adhesive tape for resin sealing in the manufacture of resin-sealed semiconductor devices. The adhesive tape includes a substrate layer and an adhesive layer laminated on the substrate layer. And it is characterized in that the adhesive layer is formed of an adhesive, and the adhesive includes a polymer and a ring containing structural units derived from (meth)acrylic acid and monomer components other than the (meth)acrylic acid An oxygen-based crosslinking agent in which the (meth)acrylic acid contains 5 parts by weight or more with respect to 100 parts by weight of the monomer component, and the epoxy-based crosslinking agent is 0.4 equivalent to the (meth)acrylic acid The above corresponding parts by weight are included."

Furthermore, Non-Patent Document 1 describes the influence of plasma on acrylic resin. Specifically, it is described that the bond is selectively cleaved at a site adjacent to the benzene ring contained in the acrylic resin by exposure to the plasma. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2004-014930 [Patent Document 2] Japanese Patent Laid-Open No. 2011-124495 [Non-Patent Literature]

[Non-Patent Document 1] "Surface Science", Vol.13, No.8, pp.478-482, 1992

[The problem to be solved by the invention]

Patent Document 2 describes that by increasing the degree of crosslinking of the polymer contained in the adhesive layer, the plasma resistance of the adhesive tape is improved. However, if the degree of crosslinking of the polymer is increased, it is difficult to ensure the adhesive force of the adhesive tape under high temperature conditions necessary to prevent mold flash.

The object of the present invention is to provide an adhesive tape and a method for manufacturing a semiconductor package using the adhesive tape, which can be cleanly peeled from the lead frame without leaving a part of the adhesive layer, and can prevent mold flash. [Means to solve the problem]

The inventors conducted diligent studies and found that by using non-aromatic acrylic polymer and metal chelate crosslinking agent to form the adhesive layer of the adhesive tape, excellent plasma resistance can be obtained, and it can be used under high temperature conditions. High adhesion can be obtained under the pressure. By having excellent plasma resistance, the modification of the adhesive layer caused by the plasma treatment can be suppressed, and the adhesive tape can be cleanly peeled from the lead frame under normal temperature conditions. In addition, by having high adhesion under high temperature conditions, mold flash can be prevented.

The present invention includes the following embodiments. [1] An adhesive tape used in the manufacturing method of semiconductor packaging, Comprising a substrate and an adhesive layer disposed on the substrate, The adhesive layer includes a non-aromatic acrylic polymer crosslinked by a metal chelate crosslinking agent. [2] The adhesive tape according to [1], wherein the metal chelate crosslinking agent contains a ligand having a boiling point of 200°C or less. [3] The adhesive tape according to [1] or [2], wherein the metal chelate crosslinking agent is an aluminum chelate crosslinking agent. [4] An adhesive tape used in a manufacturing method of a semiconductor package, comprising a substrate and an adhesive layer disposed on the substrate, and The following formula: [(A-B)/A]×100 (In the formula, A is the contact angle of the water before plasma treatment relative to the adhesive layer, B is the contact angle of the water after plasma treatment with respect to the adhesive layer) The change rate (%) of the contact angle of the water before and after the plasma treatment with respect to the adhesive layer is 10% or less, The peeling force of the adhesive tape from the copper foil is more than 100 mN/25 mm at 150°C. [5] A method for manufacturing a semiconductor package includes: In the attaching step, attach the adhesive tape as described in any one of [1] to [4] on the back of the lead frame; The fixing step: fixing the semiconductor chip to the chip pad on the surface of the lead frame to which the adhesive tape is attached; Plasma processing step, using plasma to process the surface of the semiconductor wafer and the lead frame; A connecting step, connecting the plasma-treated semiconductor wafer and the surface of the lead frame by bonding wires; A sealing step of using resin to seal the surfaces of the bonding wire, the semiconductor wafer and the lead frame; and In the peeling step, the adhesive tape is peeled from the back surface of the lead frame whose surface is sealed with the resin. [Effects of the invention]

According to the present invention, it is possible to provide an adhesive tape and a method for manufacturing a semiconductor package using the adhesive tape, which can be cleanly peeled from the lead frame without leaving a part of the adhesive layer, and can prevent mold flash.

＜Adhesive tape＞ The first embodiment of the present invention relates to an adhesive tape used in a manufacturing method of a semiconductor package, comprising a substrate and an adhesive layer disposed on the substrate, the adhesive layer comprising a metal chelate Non-aromatic acrylic polymer crosslinked by crosslinking agent. Specifically, the adhesive tape is used to prevent mold flash. By using non-aromatic acrylic polymer and metal chelate crosslinking agent, excellent plasma resistance and high adhesion under high temperature conditions can be obtained. Thereby, the adhesive tape can be cleanly peeled from the lead frame without leaving a part of the adhesive layer, and mold flash can be prevented.

The substrate of the present embodiment is not particularly limited as long as it is a heat-resistant substrate that can withstand the temperature conditions in the manufacturing process of the semiconductor package. The heat-resistant substrate is preferably a substrate that can withstand a temperature of, for example, 150°C, 170°C, 200°C, 250°C, or 300°C. As a specific substrate, for example, polyimide, polyethylene terephthalate, polyethylene naphthalate, polyether sulfide, polyether iminium, polysulfide, polyphenylene sulfide, poly Ether ether ketone, polyarylate, aromatic polyamide, etc. The thickness of the substrate is not particularly limited, and can be, for example, 5 μm to 50 μm, 10 μm to 40 μm, 20 μm to 30 μm, or the like.

The adhesive layer of this embodiment contains a non-aromatic acrylic polymer crosslinked by a metal chelate crosslinking agent. The adhesive layer contains a non-aromatic acrylic polymer to improve plasma resistance. The detailed mechanism has not yet been determined, but the inventors speculate as follows. When the adhesive layer contains an aromatic acrylic polymer, the bonds around the aromatic ring are cut intensively by the plasma treatment. As a result, the degree of modification of the surface of the adhesive layer becomes stronger, and the plasma resistance is greatly reduced. In contrast, the adhesive layer of the present embodiment contains a non-aromatic acrylic polymer, so even if the plasma treatment is performed, the concentrated cutting does not occur. As a result, the degree of modification of the surface of the adhesive layer by the plasma treatment becomes weak, and good plasma resistance can be ensured.

The non-aromatic acrylic polymer crosslinked by the metal chelate crosslinking agent may be only one type, or a combination of two or more types. When combining two or more types, at least one kind of non-aromatic acrylic polymer preferably contains 1 to 20% by weight of structural units derived from acrylic acid relative to the total amount of the non-aromatic acrylic polymer. Furthermore, a polymer usually has a molecular weight distribution, so a combination of a plurality of polymer molecules constituting the molecular weight distribution is regarded as one kind. The metal chelate crosslinking agent may be only one type or a combination of two or more types. The adhesive layer may contain further components within a range that does not impair the effects of the present invention. Examples of further components include plasticizers, pigments, dyes, antistatic agents, and fillers.

The dried thickness of the adhesive layer is preferably 2 μm to 12 μm, more preferably 4 μm to 10 μm, and still more preferably 6 μm to 8 μm.

The non-aromatic acrylic polymer of the present embodiment refers to a polymer having a structural unit derived from (meth)acrylic acid and/or a derivative thereof (hereinafter referred to as an "acrylic unit") and not containing an aromatic ring. In this specification, (meth)acrylic acid means acrylic acid and/or methacrylic acid. As a derivative of (meth)acrylic acid, (meth)acrylate etc. are mentioned, for example. As specific derivatives of (meth)acrylic acid, for example, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, methyl (meth)acrylate, ethyl (meth)acrylate Ester, isoamyl (meth)acrylate, n-hexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, (meth)acrylic acid Lauryl ester and so on. Among these, from the viewpoint of adequately ensuring room temperature viscosity, butyl acrylate and 2-ethylhexyl acrylate are preferred. In addition, the non-aromatic acrylic polymer must have a functional group for bonding with the metal chelate crosslinking agent. As the functional group, a carboxyl group is preferred. In addition, the structural unit having a functional group preferably contains 1% by weight to 20% by weight with respect to the total amount of the non-aromatic acrylic polymer.

The non-aromatic acrylic polymer may have a further structural unit in addition to the acrylic unit. Examples of further structural units include structural units derived from acrylonitrile, vinyl acetate, vinyl chloride, butadiene, isoprene, and the like.

The amount of acrylic units constituting the non-aromatic acrylic polymer is preferably 70% by weight or more, more preferably 80% by weight or more, and still more preferably 90% by weight or more with respect to the non-aromatic acrylic polymer. The upper limit of the amount of the acrylic acid unit is not particularly limited, and it can be set to 100% by weight, 95% by weight, etc., for example.

From the viewpoint of having both workability and paste residue properties, the weight average molecular weight of the non-aromatic acrylic polymer is preferably 300,000 to 1.5 million, more preferably 500,000 to 1 million.

The amount of the non-aromatic acrylic polymer relative to the adhesion layer is preferably 85% by weight to 99% by weight, more preferably 90% by weight to 98% by weight, and still more preferably 93% by weight to 97% by weight.

The metal chelate crosslinking agent of this embodiment refers to a crosslinking agent having a metal ion and a ligand. The metal chelate crosslinking agent is an ionic crosslinking agent, and therefore has a lower coefficient of elasticity at 175°C than a covalent crosslinking agent. In this way, the adhesive layer has high adhesion under high temperature conditions, which can effectively suppress mold flash. In addition, the metal chelate crosslinking agent preferably has a ligand having a boiling point of 200°C or less. Thereby, in the step of forming the adhesion layer, the ligand is volatilized due to drying, and the metal chelate crosslinking agent can irreversibly crosslink with the non-aromatic acrylic polymer. The lower limit of the boiling point of the ligand is not particularly limited. For example, it may be 60°C, 70°C, 80°C, or the like.

Examples of the metal chelate crosslinking agent having a ligand having a boiling point of 200°C or less include aluminum chelate crosslinking agents, titanium chelate crosslinking agents, and zirconium chelate crosslinking agents.

As an aluminum chelate crosslinking agent, for example, aluminum tris(acetate pyruvic acid), ethyl diacetoxyacetate aluminum monoacetate pyruvate, aluminum tris(ethylacetate), and the like can be cited. As the titanium chelate crosslinking agent, for example, diisopropoxy bis (acetate pyruvate) titanium, tetra acetyl pyruvate titanium, diisopropoxy bis (acetate ethyl acetate) titanium, di- 2-Ethylhexoxy bis(2-ethyl-3-hydroxyhexaoxide) titanium, titanium ammonium lactate, titanium lactate, diisopropoxy bis(triethanol aminated) titanium, aminoethylaminoethanol Titanium etc. Examples of the zirconium chelate crosslinking agent include zirconium tetraacetylpyruvate, zirconium tributoxymonoacetylpyruvate, zirconium dibutoxybis(ethylacetate), and zirconium ammonium lactate. Although not particularly limited, from the standpoint of shelf life, the metal chelate crosslinking agent is preferably an aluminum chelate crosslinking agent, more preferably aluminum tris(acetylpyruvate).

The amount of the metal chelate crosslinking agent is preferably 1% by weight to 15% by weight relative to the adhesive layer, more preferably 2% by weight to 10% by weight, and still more preferably 3% by weight to 7% by weight.

The adhesive tape of this embodiment may include a release film on the adhesive layer.

The adhesive tape of this embodiment can be manufactured by a well-known method. For example, it can include a step of mixing a non-aromatic acrylic polymer, a metal chelate crosslinking agent, and a solvent (mixing step), a step of applying the mixture to a substrate (coating step), and a step of applying the mixture The drying step (drying step) is used to manufacture the adhesive tape.

Examples of solvents used in the mixing step include ketone solvents (acetone, methyl ethyl ketone, acetone, etc.), alcohol solvents (methanol, ethanol, propanol, butanol, etc.), ether solvents (tetrahydrofuran, etc.), Nitrile solvents (acetonitrile, etc.), amide solvents (N,N-dimethylformamide, etc.), etc.

As the coating method in the coating step, for example, die coater coating, bar coater coating, air knife coater coating, gravure coater coating, reverse roll coater coating, Lip coater coating etc.

The adhesive tape of this embodiment may further have the characteristics of the adhesive tape of the following second embodiment.

The second embodiment of the present invention relates to an adhesive tape used in a manufacturing method of a semiconductor package, comprising a substrate and an adhesive layer disposed on the substrate, and has the following formula: [(A-B)/A]×100 (In the formula, A is the contact angle of the water before plasma treatment relative to the adhesive layer, B is the contact angle of the water after plasma treatment with respect to the adhesive layer) The change rate (%) of the contact angle of the water before and after the plasma treatment with respect to the adhesive layer is 10% or less, The peeling force of the adhesive tape from the copper foil is more than 100 mN/25 mm at 150°C. Specifically, the adhesive tape is used to prevent mold flash.

If the contact angle of the water with respect to the adhesive layer is reduced by the plasma treatment, the adhesive force of the adhesive layer increases, and the adhesive tape cannot be cleanly peeled from the lead frame. On the other hand, by setting the change rate (%) of the contact angle of water before and after the plasma treatment to 10% or less, the increase in adhesive force can be suppressed and the adhesive tape can be peeled cleanly under normal temperature conditions. In addition, by making the peeling force of the adhesive tape 100 mN/25 mm or more at 150°C, mold flash can be prevented.

The change rate (%) of the contact angle of water with respect to the adhesive layer before and after the plasma treatment is preferably 10% or less, more preferably 5% or less, and still more preferably 3% or less. The lower limit of the rate of change (%) is not particularly limited, and can be set to 0%, 1%, etc., for example. The contact angle before and after the plasma treatment can be measured by the method described in the following examples, and the rate of change can be calculated based on the measured contact angle.

In order to cleanly peel the adhesive tape from the lead frame, the lower the peel force of the adhesive tape under normal temperature conditions, the better. Specifically, it is preferably less than 1200 mN/25 mm at 25°C, and more preferably less than 500 mN/25 mm. The peel force of the adhesive tape at 25°C can be measured by the method described in the following examples. The lower limit of the peeling force of the adhesive tape at 25°C is not particularly limited, and may be, for example, 100 mN/25 mm, 200 mN/25 mm, or the like.

From the viewpoint of ensuring mold flash resistance, the higher the peel force of the adhesive tape under high temperature conditions, the better. Specifically, it is preferably 100 mN/25 mm or more at 150°C, more preferably 150 mN/25 mm or more. The peeling force of the adhesive tape at 150°C can be measured by the method described in the following examples. The upper limit of the peeling force of the adhesive tape at 150°C is not particularly limited, and may be, for example, 500 mN/25 mm, 1000 mN/25 mm, or the like.

In order to ensure mold flash resistance and fully connect the semiconductor chip and the surface of the lead frame by bonding wires, the elastic coefficient of the adhesive tape is preferably 5×10 ⁵ Pa to 20×10 ⁵ Pa at 175°C, and more preferably 5×10 ⁵ Pa～10×10 ⁵ Pa. The elastic coefficient of the adhesive tape can be measured by the method described in the following examples.

The adhesive tape of this embodiment may further have the characteristics of the adhesive tape of the first embodiment.

＜Method of manufacturing semiconductor package＞ The third embodiment of the present invention relates to a method for manufacturing a semiconductor package, which includes an attaching step, a fixing step, a plasma treatment step, a connecting step, a sealing step, and a peeling step. Hereinafter, each step will be described.

The attaching step of this embodiment is a step of attaching the adhesive tape of the first embodiment or the second embodiment to the back surface of the lead frame. The attaching step can be performed by a known method.

The fixing step of this embodiment is a step of fixing the semiconductor chip to the chip pad on the surface of the lead frame to which the adhesive tape is attached. The fixing step can be performed by a known method.

The plasma processing step of this embodiment is a step of processing the surfaces of the semiconductor wafer and the lead frame with plasma. The plasma treatment step can be performed by a known method. For example, it can be used in an inert gas (argon, nitrogen, etc.) environment at 50 W to 300 W (preferably 100 W to 150 W), 5 seconds to 60 seconds (preferably 10 seconds to 30 seconds) Under the plasma treatment.

The connecting step of this embodiment is a step of connecting the plasma-processed semiconductor wafer and the surface of the lead frame using bonding wires. The connecting step can be performed by a known method.

The sealing step of this embodiment is a step of sealing the surfaces of the bonding wire, the semiconductor wafer, and the lead frame with resin. The sealing step can be performed by a known method. For example, the sealing step may be performed at 110°C to 200°C, preferably 130°C to 180°C.

The peeling step of this embodiment is a step of peeling the adhesive tape from the back surface of the lead frame whose surface is sealed with resin. The peeling step can be performed by a known method.

In the case where the lead frame has a plurality of die pads on the surface and the plurality of semiconductor wafers are fixed to the plurality of die pads, the manufacturing method of this embodiment may further include a cutting step: peeling off the adhesive tape, using The lead frame whose surface is sealed with resin is cut into individual semiconductor packages. [Example]

Hereinafter, the present invention will be explained in more detail using examples and comparative examples, but the technical scope of the present invention is not limited to these.

＜Polymer＞ The following polymers were used in Examples and Comparative Examples. (1) Acrylic polymer A Add Butyl Acrylate (BA) (92 parts by weight), Acrylic Acid (AA) (8 parts by weight), ethyl acetate (100 parts by weight) and azobisisobutyronitrile (Azobisisobutyronitrile) into the reaction vessel. , AIBN) (0.3 parts by weight), stirring at 70°C. After 60 minutes from the start of the reaction, a portion of the reaction solution was taken out every 30 minutes, the reaction was stopped with deionized water, extracted with methyl ethyl ketone, and the extracted solution was analyzed by Gel Permeation Chromatography (GPC). According to GPC analysis, the reaction vessel was cooled to stop the reaction when the weight average molecular weight of the reactant reached 700,000 or more. The obtained mixture was washed with deionized water and dried to obtain acrylic polymer A. The weight average molecular weight of the acrylic polymer A was 750,000, and the acid value obtained by titration with a potassium hydroxide aqueous solution was 810 mgKOH/g.

(2) Acrylic polymer B Add butyl acrylate (BA) (82 parts by weight), Acrylonitrile (AN) (12 parts by weight), and 2-Hydroxy Ethyl Acrylate (2HEA) (5 parts by weight) to the reaction vessel , Acrylic acid (AA) (1 part by weight), ethyl acetate (100 parts by weight) and azobisisobutyronitrile (AIBN) (0.3 parts by weight), stir at 70°C. After 60 minutes from the start of the reaction, a part of the reaction solution was taken out every 30 minutes, the reaction was stopped with deionized water, extracted with methyl ethyl ketone, and the extracted solution was analyzed by gel permeation chromatography (GPC). According to the GPC analysis, the reaction vessel was cooled when the weight average molecular weight of the reactant reached 500,000 or more to stop the reaction. The obtained mixture was washed with deionized water and dried to obtain acrylic polymer B. The weight average molecular weight of acrylic polymer B is 540,000.

(3) Acrylic polymer C Add butyl acrylate (BA) (72 parts by weight), styrene (Styrene, ST) (20 parts by weight), acrylic acid (AA) (8 parts by weight), ethyl acetate (100 parts by weight), and Azobisisobutyronitrile (AIBN) (0.3 parts by weight), stirred at 70°C. After 60 minutes from the start of the reaction, a part of the reaction solution was taken out every 30 minutes, the reaction was stopped with deionized water, extracted with methyl ethyl ketone, and the extracted solution was analyzed by gel permeation chromatography (GPC). According to the GPC analysis, the reaction vessel was cooled when the weight average molecular weight of the reactant reached 100,000 or more to stop the reaction. The obtained mixture was washed with deionized water and dried to obtain acrylic polymer C. The weight average molecular weight of the acrylic polymer C is 120,000, and the acid value obtained by titration with an aqueous potassium hydroxide solution is 670 mgKOH/g.

＜Crosslinking agent＞ In the Examples and Comparative Examples, the following crosslinking agents were used. (1) Aluminum chelate crosslinking agent [Tris(acetylpyruvate) aluminum, trade name: ORGATIX AL-3100 (manufactured by Matsumoto Fine Chemical Co., Ltd.)] (2) Titanium chelate crosslinking agent [diisopropoxy bis(acetylpyruvate) titanium, trade name: ORGATIX TC-100 (manufactured by Matsumoto Fine Chemical Co., Ltd.) )] (3) Zirconium chelate crosslinking agent [Zirconium tetraacetylpyruvate, trade name: ORGATIX ZC-700 (manufactured by Matsumoto Fine Chemical Co., Ltd.)] (4) Phenolic novolac type epoxy resin crosslinking agent [trade name: EPICLON N730A (manufactured by DIC Co., Ltd.)] (5) Alicyclic epoxy resin crosslinking agent A [trade name: EHPE3150 (made by Daicel Co., Ltd.)] (6) Alicyclic epoxy resin crosslinking agent B [trade name: Tetrad-C (manufactured by Mitsubishi Gas Chemical Co., Ltd.)] (7) Imidazole-based catalyst [trade name: Curezol C11Z (manufactured by Shikoku Chemical Industry Co., Ltd.)] (8) Isocyanate type crosslinking agent [trade name: Duranate SBN-70D (manufactured by Asahi Kasei Co., Ltd.)]

[Example 1] ＜Manufacture of adhesive tape＞ Stir the acrylic polymer A (100 parts by weight), aluminum chelate crosslinking agent (4 parts by weight), acetone (10 parts by weight) and methyl ethyl ketone (60 parts by weight) at room temperature to obtain Composition 1. The composition 1 was coated on a polyimide film (thickness 25 μm) using a die coater so that the thickness after drying became 7 μm, and dried at 150° C. for 5 minutes to obtain an adhesive tape. The mold release surface of the mold release film which performed the mold release process was laminated on the adhesive layer of an adhesive tape by lamination, and it heated at 105 degreeC for 24 hours, and obtained the adhesive tape with a mold release film.

＜The rate of change of the contact angle of water＞ The adhesive tape with the release film is divided into two adhesive tapes, the first adhesive tape and the second adhesive tape, the release film is removed, and the electricity is fully eliminated. Under the conditions of argon atmosphere (flow rate 50 cc), 120 W, 20 seconds, only the second adhesive tape is plasma treated. Fix the first adhesive tape and the second adhesive tape on the pedestal of the contact angle meter [product name: CA-X (manufactured by Kyowa Interface Science Co., Ltd.)] at 23°C with the adhesive layer facing upwards, and measure the direction The contact angle of the adhesive layer when pure water is dropped. The measurement was performed 10 times, and the average value was calculated. Based on the average value of the contact angle and the following formula, the rate of change of the contact angle of water was calculated. Change rate of the contact angle of water (%)=[(Contact angle of water with respect to the first adhesive tape-Contact angle of water after plasma treatment with respect to the second adhesive tape)/Contact of water with respect to the first adhesive tape Angle]×100

The rate of change of the contact angle of the water was evaluated using the following criteria. The results are shown in Table 1. ◎: The rate of change of the contact angle of water is 5% or less ○: The change rate of the contact angle of water is greater than 5% and less than 10% △: The change rate of the contact angle of water is greater than 10% and less than 15% ×: The change rate of the contact angle of water is greater than 15%

＜Measurement of peel strength＞ The adhesive tape was roll-laminated (30°C, 0.4 MPa, 1 m/min) on the glossy side of the rolled copper foil (thickness 35 μm), and then a 25 mm wide test piece was prepared. The rolled copper foil surface of the produced test piece and the stainless steel plate were bonded with double-sided tape, and the peeling force when the adhesive tape was peeled off at a speed of 200 mm/min in the 180° direction at 25°C and 150°C was measured . The peeling force was evaluated using the following criteria. The results are shown in Table 1.

[Peel strength under 25℃ environment] ◎: Peeling force is less than 500 mN/25 mm ○: The peeling force is 500 mN/25 mm or more and less than 1200 mN/25 mm △: The peeling force is 1200 mN/25 mm or more and less than 1300 mN/25 mm ×: Peeling force is 1300 mN/25mm or more

[Peel strength under 150℃ environment] ◎: Peeling force is 150 mN/25 mm or more ○: The peeling force is more than 100 mN/25 mm and less than 150 mN/25 mm △: The peeling force is more than 50 mN/25 mm and less than 100 mN/25 mm ×: Peeling force is less than 50 mN/25 mm

＜Measurement of coefficient of elasticity＞ The adhesive composition was coated on the release film so that the thickness after drying became 100 μm, and after drying, it was heated at 105° C. for 24 hours to remove the release film, thereby obtaining a single film of the adhesive. With respect to the obtained single film, the storage elastic coefficient (E') at 23° C. to 200° C. was measured under the conditions of a temperature increase rate of 10° C./min and 1 Hz using a dynamic viscoelasticity measurement (DMA: Dynamic Mechanical Analysis) device. Among them, the value at 175°C was evaluated using the following criteria. The results are shown in Table 1.

◎: Storage elasticity coefficient at 175℃ is 5×10 ⁵ Pa or more and less than 10×10 ⁵ Pa ○: Storage elasticity coefficient at 175℃ is 10×10 ⁵ Pa or more and less than 20×10 ⁵ Pa △: 175℃ The storage elasticity coefficient under the temperature is 20×10 ⁵ Pa or more and less than 30×10 ⁵ Pa ×: The storage elasticity coefficient at 175℃ is 30×10 ⁵ Pa or more

[Example 2 to Example 4 and Comparative Example 1 to Comparative Example 7] Using the polymers and crosslinking agents shown in Table 1 and Table 2, an adhesive tape with a release film was produced in the same manner as in Example 1, and the rate of change in the contact angle of water was calculated. In addition, the peeling force and the coefficient of elasticity were measured. The results are shown in Table 1 and Table 2.

[Table 1] Example 1 Example 2 Example 3 Example 4 Acrylic polymer A 100 100 100 70 Acrylic polymer B - - - 30 Aluminum chelate crosslinker 4 - - 4 Titanium chelate crosslinking agent - 4 - - Zirconium chelate crosslinking agent - - 6 - Change rate of water contact angle (%) ◎ ◎ ◎ ◎ Peeling force (mN/25 mm) 25℃ ○ ○ ○ ○ 150°C ○ ○ ◎ ◎ Elastic coefficient (×10 ⁵ Pa) ◎ ◎ ◎ ◎ The unit of the numerical value of the adhesive tape component is part by weight.

[Table 2] Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Comparative example 6 Comparative example 7 Acrylic polymer A 100 100 100 100 - - - Acrylic polymer C - - - - 100 100 100 Phenol novolac type epoxy resin crosslinking agent 8 - - - - - - Alicyclic epoxy resin crosslinking agent A - 8 - - 8 - - Alicyclic epoxy crosslinking agent B - - 6 - - - - Imidazole-based catalyst 0.2 0.2 0.2 - 0.2 - - Aluminum chelate crosslinker - - - - - 4 - Isocyanate type crosslinking agent - - - 14 - - 14 Change rate of water contact angle (%) ○ X △ ◎ X △ X Peeling force (mN/25 mm) 25℃ ◎ ◎ ◎ ○ ○ X ○ 150°C X X X X X ◎ △ Elastic coefficient (×10 ⁵ Pa) △ X X ○ X ◎ ○ The unit of the numerical value of the adhesive tape component is part by weight.

As shown in the results of Table 1 and Table 2, the adhesive tapes of Examples 1 to 4 have plasma resistance and therefore can be peeled cleanly from the lead frame without leaving a part of the adhesive layer. In addition, the adhesive tapes of Examples 1 to 4 have excellent adhesive force under high temperature conditions, so mold flash can be suppressed.

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Claims (5)

An adhesive tape used in a manufacturing method of semiconductor packaging, including: A substrate, and an adhesive layer disposed on the substrate, The adhesive layer includes a non-aromatic acrylic polymer crosslinked by a metal chelate crosslinking agent. The adhesive tape described in item 1 of the scope of patent application, wherein the metal chelate crosslinking agent contains a ligand having a boiling point of 200°C or less. The adhesive tape according to item 1 or item 2 of the scope of patent application, wherein the metal chelate crosslinking agent is an aluminum chelate crosslinking agent. An adhesive tape used in a manufacturing method of a semiconductor package, comprising: a substrate, and an adhesive layer disposed on the substrate, and From the following formula: [(A-B)/A]×100 (In the formula, A is the contact angle of the water before plasma treatment relative to the adhesive layer, B is the contact angle of the water after plasma treatment with respect to the adhesive layer) The change rate (%) of the contact angle of the water before and after the plasma treatment with respect to the adhesive layer is 10% or less, The peeling force of the adhesive tape from the copper foil is more than 100 mN/25 mm at 150°C. A method for manufacturing a semiconductor package includes: In the attaching step, attach the adhesive tape as described in any one of items 1 to 4 of the scope of patent application on the back of the lead frame; The fixing step: fixing the semiconductor chip to the chip pad on the surface of the lead frame to which the adhesive tape is attached; Plasma processing step, using plasma to process the surface of the semiconductor wafer and the lead frame; A connecting step, connecting the plasma-treated semiconductor wafer and the surface of the lead frame by bonding wires; A sealing step of using resin to seal the surfaces of the bonding wire, the semiconductor wafer and the lead frame; and In the peeling step, the adhesive tape is peeled from the back surface of the lead frame whose surface is sealed with the resin.