JP2012059846A - Adhesive film for semiconductor production - Google Patents

Abstract

An adhesive film that protects an outer lead portion of a lead frame when a semiconductor package such as QFN is sealed prevents adhesive residue when the adhesive film is peeled from the lead frame.
An adhesive film for manufacturing a semiconductor comprising at least a heat-resistant film and an adhesive layer, which is used by being attached to a lead frame in a semiconductor manufacturing process, the surface free energy required by a contact angle method of the heat-resistant film Can be solved by the pressure-sensitive adhesive film for semiconductor production, which is 90 to 160 mN / m. The pressure-sensitive adhesive film is obtained by subjecting a heat resistant film such as polyimide to plasma treatment or corona treatment, and then laminating a pressure-sensitive adhesive layer.
[Selection figure] None

Description

The present invention relates to a peelable adhesive film for manufacturing a semiconductor, which is used by being attached to a lead frame when manufacturing a semiconductor package, and a method for manufacturing the same.

Along with the needs for downsizing and weight reduction of electronic devices, the electronic components incorporated therein are also required to be downsized and mounted with high density. In response to this, instead of the peripheral terminal packages SOP (Small Outline Package) and QFP (Quad Flat Package) that have been used in the past, area array mounting packages BGA (Ball Grid Array), CSP (Chip Size Package) System-implemented SIP (System In Package) and MCP (Multi Chip Package) have been developed. QFN (Quad Flat No Leaded Package) is a package developed to reduce the size and height of QFP, and can use the same manufacturing technology as QFP. Widely used in equipment. The QFN can be externally connected on the back surface of the package by disposing the outer leads in the sealing region, and can be reduced in size compared to the QFP. On the other hand, since there is an outer lead portion in the sealing region, there is a problem of so-called mold flash in which the sealing resin wraps around. In order to prevent this, it is effective to protect the outer lead portion of the lead frame with an adhesive film at the time of sealing.

From such a viewpoint, various pressure-sensitive adhesive sheets used for semiconductor packages such as QFN have been proposed. For example, a mask sheet for assembling a semiconductor device is proposed in which an adhesive layer made of a silicone-based pressure-sensitive adhesive is provided on a heat-resistant film, and the weight loss when heated at 180 ° C. for 1 hour is 5% or less ( Patent Document 1). However, in the mask sheet disclosed therein, adhesive residue remains on the lead frame when it is peeled off from the lead frame after being heated to a high temperature in a heating process such as die attach, wire bonding, or resin sealing. Therefore, there is a problem that the heating temperature and time in these heating steps are limited.

In addition, as an attempt to prevent adhesive residue without causing mold flash, a heat-resistant adhesive tape composed of a base material layer and an adhesive layer containing a release agent and a method for manufacturing a semiconductor device using the same are proposed. (Patent Document 2). However, even with the adhesive tape disclosed therein, no attention is paid to the surface free energy of the base material layer, so that it is difficult to completely prevent mold flash, and at the same time, lead by a mold release agent. There was a problem of frame contamination.

In addition, as an attempt to solve these problems, an adhesive sheet for manufacturing a semiconductor device in which an adhesive layer contains thermoplastic polyimide has been proposed (Patent Document 3). However, the adhesive sheet disclosed therein needs to be heat-bonded when affixed to the lead frame, so that a special laminating apparatus is required and there are problems such as dimensional deviation and warping after laminating. there were.

JP 2002-275435 A JP 2005-209936 A JP 2003-188334 A

The present invention has been made in view of the above-mentioned problems in the prior art, that is, an adhesive film for semiconductor manufacturing that can be applied at room temperature during the semiconductor assembly process, prevents mold flash, and has no adhesive residue at the time of peeling. And its manufacturing method.

According to this invention, the following adhesive films for semiconductor manufacture are provided.
[1] A pressure-sensitive adhesive film for manufacturing a semiconductor comprising at least a heat-resistant film and a pressure-sensitive adhesive layer, which is used by being attached to a lead frame in a semiconductor manufacturing process,
The adhesive film for semiconductor manufacture, wherein the surface free energy required by the contact angle method of the heat resistant film is 90 to 160 mN / m.

[2] Dispersion component of surface free energy of the heat-resistant film determined by a contact angle method using water, diiodomethane and ethylene glycol is 10 to 30 mN / m, dipole component is 40 to 110 mN / m, hydrogen bonding component Is 20 to 40 mN / m, the adhesive film for semiconductor production according to [1].

[3] The heat-resistant film is an aromatic polyimide film having an average linear expansion coefficient of 50 to 200 ° C. of 10 to 50 ppm / K and a thickness of 5 to 100 μm [1] or [1] 2] The adhesive film for semiconductor manufacture as described in 2].

  [4] The adhesive film for semiconductor production according to any one of [1] to [3], wherein the heat-resistant film has been subjected to at least one surface treatment of plasma treatment or corona treatment.

  [5] The pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer made of a silicone-based pressure-sensitive adhesive composition of a peroxide curable type or an addition reaction curable type having a thickness of 1 to 50 μm [1]. Thru | or the adhesive film for semiconductor manufacture in any one of [4].

[6] The adhesive film for semiconductor production according to any one of [1] to [5], wherein the adhesive layer has a thermal weight loss rate of 50% or less between 50 and 200 ° C.

  [7] A pressure-sensitive adhesive layer is formed on a heat-resistant film having a surface free energy of 90 to 160 mN / m determined by a contact angle method via a primer layer [1] to [6] ] The adhesive film for semiconductor manufacture in any one of.

[8] The adhesive film for semiconductor production according to [7], wherein the primer layer contains polyorganosiloxane and is cured by either an addition reaction or a condensation reaction.

  [9] The adhesive film for semiconductor production according to [7] or [8], wherein the primer layer has a thickness of 0.01 to 5.0 μm.

Moreover, the manufacturing method of the following adhesive films for semiconductor manufacture is also one of this invention.
[10] A method for producing a pressure-sensitive adhesive film for semiconductor production comprising at least a heat-resistant film and a pressure-sensitive adhesive layer used by being attached to a lead frame in a semiconductor production process,
The surface free energy required by the contact angle method of the heat resistant film is 90 to 160 mN / m in advance,
Then, a pressure-sensitive adhesive layer is formed. A method for producing a pressure-sensitive adhesive film for semiconductor production.

  [11] The pressure-sensitive adhesive film for semiconductor production according to [10], wherein the heat-resistant film is subjected to plasma treatment or corona treatment so that the surface free energy obtained by the contact angle method is 90 to 160 mN / m. Manufacturing method.

  [12] The semiconductor according to [10] or [11], wherein a pressure-sensitive adhesive layer is further formed after forming a primer layer on a heat-resistant film whose surface free energy is 90 to 160 mN / m in advance. A method for producing an adhesive film for production.

  According to [1] and [2] of the present invention, the surface free energy of the heat-resistant film and its dispersion component, dipole component, and hydrogen bond component are controlled to an appropriate range so that they are attached to the lead frame at room temperature. Even when an adhesive that can be applied is used, a pressure-sensitive adhesive film for semiconductor production that does not cause a problem such as mold flash or adhesive residue is provided.

  According to [3] of the present invention, by using an aromatic polyimide film having an average linear expansion coefficient of 50 to 200 ppm / K and a thickness of 5 to 100 μm as the heat resistant film, When the semiconductor manufacturing adhesive film of the invention is applied to a lead frame to manufacture a semiconductor, there is less possibility of problems such as warping and deformation in a thermal process such as wire bonding and resin sealing.

  According to [4] of the present invention, the surface free energy of the heat-resistant film can be easily controlled within an appropriate range by using a plasma-treated or corona-treated heat-resistant film, such as mold flash or adhesive residue. It is possible to easily obtain a pressure-sensitive adhesive film for semiconductor production that does not cause a problem.

  According to [5] of the present invention, as the pressure-sensitive adhesive layer, a pressure-sensitive adhesive layer made of either a peroxide-curing type or an addition reaction-curing silicone-based pressure-sensitive adhesive composition is used. Therefore, it is possible to easily form an adhesive layer effective for preventing mold flash and adhesive residue.

  According to [6] of the present invention, a pressure-sensitive adhesive layer having a thermal weight reduction rate of 50% or less between 50 and 200 ° C. is used, and the heat resistance of the pressure-sensitive adhesive film for semiconductor production of the present invention is improved. There is no risk of problems such as mold flash and adhesive residue, and a more reliable semiconductor can be manufactured.

According to [7] of the present invention, the primer layer is formed on the heat-resistant film whose surface free energy is controlled in an appropriate range, and the pressure-sensitive adhesive layer is further formed. Thus, there can be obtained a pressure-sensitive adhesive film for manufacturing semiconductors, which has no fear of adhesive residue and is less likely to cause defects such as repellency and pinholes during the formation of the pressure-sensitive adhesive layer.

  According to [8] of the present invention, the primer layer contains polyorganosiloxane that is cured by addition reaction or condensation reaction, and the adhesive force of the pressure-sensitive adhesive layer to the heat-resistant film is further improved.

  According to [9] of the present invention, the primer layer has a thickness of 0.01 to 5 μm, and it becomes easy to form a primer layer having a uniform thickness without repelling or uneven coating.

  According to [10] to [12] of the present invention, it is possible to easily produce an adhesive film for semiconductor production which is effective for mold flash and prevention of adhesive residue.

Hereinafter, the adhesive film for semiconductor production of the present invention will be described in detail.
The pressure-sensitive adhesive film for semiconductor production of the present invention (hereinafter also simply referred to as “pressure-sensitive adhesive film”) is used by sticking to a lead frame in a semiconductor manufacturing process, and is composed of at least a heat-resistant film and a pressure-sensitive adhesive layer. And the surface free energy calculated | required by the contact angle method of the said heat resistant film shall be 90-160 mN / m.

  The thickness of the heat-resistant film used for the pressure-sensitive adhesive film of the present invention is not particularly limited, but is preferably in the range of 5 to 200 μm, more preferably 10 to 100 μm, and still more preferably 15 to 75 μm. When the thickness of the heat resistant film is less than 5 μm, it becomes difficult to form an adhesive layer on the heat resistant film, and the adhesive film of the present invention is attached to a lead frame and further sealed with a mold resin. At this time, there is a possibility that problems such as wrinkling and elongation of the adhesive film may occur. Further, when the thickness of the heat resistant film exceeds 200 μm, the rigidity becomes high, it becomes difficult to attach the lead frame to the lead frame, and there is a possibility that it is economically disadvantageous.

  In addition, in the semiconductor manufacturing process, the adhesive film is exposed to a high temperature atmosphere in a die attach process, a wire bonding process, a resin sealing process, etc., but if the linear expansion coefficient of the heat resistant film is significantly different from that of the lead frame, When it is returned to room temperature after being exposed to a high temperature atmosphere, warpage occurs, and the lead frame cannot be set on the positioning pins of the mold, which may cause a problem of misalignment. Therefore, it is preferable that the average linear expansion coefficient in 50-200 degreeC of the heat resistant film used for this invention is 10-50 ppm / K, More preferably, it is 12-30 ppm / K.

The heat-resistant film used for the adhesive film of the present invention is a plastic film having a glass transition temperature of 100 ° C. or higher or having no glass transition temperature. Polyimide, polyamide, polyamideimide, polyetherimide, polyester And plastic films such as polyphenylene sulfide, polysulfone, and polyether sulfone. Polyimide films are preferable from the viewpoint of heat resistance.

  The heat-resistant film used in the present invention is characterized in that the surface free energy required by the contact angle method is 90 to 160 mN / m, and preferably 100 to 160 mN / m.

を保って平衡に達しているとすると、非特許文献１にある拡張Ｆｏｗｋｅｓ理論によれば数式１が成り立つ。ここでγ_Lは液体の表面自由エネルギーであり、表面自由エネルギーの分散成分γ_L ^d、双極子成分γ_L ^p及び水素結合成分γ_L ^hの和、γ_L ^d＋γ_L ^p＋γ_L ^hとして表わされる。 The surface free energy of the film can be obtained by the following principle and method.
In the present invention, the solid surface free energy γ _S of the heat-resistant film is the sum of the surface free energy dispersion component γ _S ^d , dipole component γ _S ^p and hydrogen bond component γ _S ^h , γ _S ^d + γ _S ^p + γ _S ^Expressed as ^h . Droplet contact angle on solid surface

If Eq. 1 is maintained and equilibrium is reached, according to the extended Fowkes theory in Non-Patent Document 1, Equation 1 holds. Where γ _L is the surface free energy of the liquid, expressed as the sum of the dispersion component γ _L ^d , dipole component γ _L ^p and hydrogen bond component γ _L ^h of the surface free energy, γ _L ^d + γ _L ^p + γ _L ^h. It is.

、ジヨードメタンの接触角

及びエチレングリコールの接触角

を測定し、それぞれの液体のγ_L、γ_L ^d、γ_L ^p、γ_L ^hの値を代入した数式２〜４を用いて表面自由エネルギーの各成分を計算した。 When the contact angles are measured for three liquids with known γ _L , γ _L ^d , γ _L ^p , and γ _L ^h , the surface free energy γ _S of the solid can be obtained from a ternary simultaneous equation. Non-Patent Document 1 describes the surface free energy of a standard liquid, and the surface free energy of the heat-resistant film in the present invention is the contact angle of water.

Contact angle of diiodomethane

And contact angle of ethylene glycol

Then, each component of the surface free energy was calculated using Equations 2 to 4 in which the values of γ _L , γ _L ^d , γ _L ^p , and γ _L ^h of each liquid were substituted.

According to Non-Patent Document 1, the surface free energy represented by the dispersion component, dipole component, hydrogen bond component, and sum of water surface energy is 29.1 mN / m, 1.3 mN / m, 42.4 mN / m and 72.8 mN / m for diiodomethane, 46.8 mN / m, 4.0 mN / m, 0 and 50.8 mN / m, respectively, and 30 for ethylene glycol. 1 mN / m, 0, 17.6 mN / m, and 47.7 mN / m.

Journal of Japan Adhesion Association 8 (3), 131-141 (1972)

In the present invention, by setting the surface free energy of the heat-resistant film to 90 to 160 mN / m, high adhesiveness between the heat-resistant film and the pressure-sensitive adhesive layer is obtained, and the pressure-sensitive adhesive is used to prevent leakage of a semiconductor sealing resin called mold flash. Even if the adhesion of the lead frame is increased, it is possible to prevent adhesive residue at the time of re-peeling. When the surface free energy of the heat-resistant film is less than 90 mN / m, it becomes difficult to obtain adhesion between the heat-resistant film and the pressure-sensitive adhesive layer, and adhesive residue is easily generated when the pressure-sensitive film is peeled off from the lead frame. On the other hand, in order to obtain a surface free energy of 160 mN / m or more, it is necessary to make the plasma energy extremely strong. Therefore, the surface of the heat-resistant film is damaged, and a fragile layer is created, which is not preferable. It is also economically disadvantageous.

Moreover, in this invention, it is preferable that the dipole component and the hydrogen bond component which are the components of the surface free energy of a heat-resistant film are 40-110 mN / m and 20-40 mN / m, respectively.
When the dipole component and the hydrogen bond component of the surface free energy are 40 mN / m and 20 mN / m or less, respectively, the surface free energy is not sufficient, and the adhesion between the heat resistant film and the pressure-sensitive adhesive layer cannot be obtained. . In addition, when the dipole component and the hydrogen bond component of the surface free energy are 110 mN / m or more and 40 mN / m or more, friction on the surface of the heat resistant film is increased, and there are problems such as wrinkles and static electricity in the manufacturing process. It tends to occur.

The surface free energy of the heat resistant film can be appropriately adjusted by subjecting the heat resistant film to surface treatment such as plasma treatment or corona treatment. In particular, using a low-temperature plasma processing apparatus capable of depressurization, introducing a plasma gas so that the pressure is 1.0 Pa to 150 Pa, applying a voltage of 0.1 to 10 kV to generate a plasma by glow discharge, By irradiating the generated heat-resistant film to the heat-resistant film, the surface of the heat-resistant film is modified, and the surface free energy can be easily controlled to 90 to 160 mN / m. As the plasma gas, oxygen, nitrogen, water, carbon dioxide, argon, or a mixture thereof can be used.

  The pressure-sensitive adhesive film of the present invention can be obtained by forming a pressure-sensitive adhesive layer directly or via a primer layer on a heat-resistant film having a surface free energy of 90 to 160 mN / m.

The adhesive layer can use any adhesive such as silicone, acrylic, olefin, etc., but can be attached to the lead frame at room temperature, and in the semiconductor manufacturing process, the die attach process, There is little change of decomposition, deterioration, etc. with respect to the heat history in the wire bonding process or resin sealing process, etc., and it shows a stable adhesive force. Furthermore, when it peels off from the lead frame after sealing, From the viewpoint of preventing the remainder from occurring, a silicone-based pressure-sensitive adhesive is particularly preferable.

Silicone pressure-sensitive adhesives mainly include addition-curing types and peroxide-curing types depending on the type of crosslinking reaction, and any type can be used in the present invention. Of these, the addition curing type using siloxanes with alkenyl groups introduced into the polyorganosiloxane and SiH groups as the crosslinking agent has a low curing temperature and is more stable than the peroxide reaction type that forms and reacts with radicals. It is easy and advantageous, and is preferable.

The pressure-sensitive adhesive layer preferably has a weight reduction rate of 5% or less when heated from 50 ° C. to 200 ° C., more preferably 3% or less, and even more preferably 2% or less. If the weight reduction rate is greater than 5%, the lead frame is contaminated in the semiconductor manufacturing process, and problems such as poor bonding of wires are likely to occur.

Various additives such as a plasticizer, a filler, and an antioxidant can be added to the pressure-sensitive adhesive layer.

It is preferable that the thickness of an adhesive layer is 1-50 micrometers, More preferably, it is 3-30 micrometers, More preferably, it is 5-20 micrometers. When the thickness of the pressure-sensitive adhesive layer is less than 1 μm, it becomes difficult to follow the irregularities on the surface of the lead frame, and therefore, filling between the pressure-sensitive adhesive and the lead frame cannot be performed, and mold flash tends to occur. On the other hand, when the pressure-sensitive adhesive layer exceeds 50 μm, the bonding energy loss at the time of wire bonding becomes large, causing wire bonding failure and increasing the adhesive force to the lead frame and the sealing resin. There is a possibility that the workability of the apparatus becomes worse, and it is also disadvantageous economically.

The pressure-sensitive adhesive layer can be formed on the heat-resistant film by directly forming the pressure-sensitive adhesive layer on the heat-resistant film having a surface free energy of 90 to 160 mN / m, or by forming a pressure-sensitive adhesive layer via a primer layer or the like. You may do it. In particular, by forming a primer layer on a heat-resistant film having a surface free energy of 90 to 160 mN / m and forming an adhesive layer thereon, the heat-resistant film and the adhesive layer can be bonded more firmly. This is preferable because the problem of adhesive residue on the lead frame can be more reliably prevented.

As the primer layer, a primer layer mainly composed of organopolysiloxane can be suitably used. In the present invention, when a primer layer mainly composed of an organopolysiloxane is used, for example, a solution containing an organopolysiloxane composition is applied to a heat-resistant film, dried after the solvent, and further cured by heating. The thickness of the primer layer is preferably 0.01 μm to 5 μm, more preferably 0.1 μm to 1 μm. When the thickness of the primer layer is smaller than 0.01 μm, it is difficult to stably form the primer layer and it is difficult to obtain the effect of improving the adhesion as the primer layer. Moreover, when the thickness of a primer layer becomes larger than 5 micrometers, the thickness of a primer layer tends to become non-uniform | heterogenous, it will become easy to produce the thickness nonuniformity of the adhesive film obtained, and it will also become economically disadvantageous.

Examples of organopolysiloxane compositions that can be suitably used as a primer layer include condensation-curable organopolysiloxanes having the chemical structures of formulas (1) and (2) and alkoxy having the structure of formula (3). Examples thereof include a mixture of a monomer having both a silyl group and a radically polymerizable unsaturated group and a copolymer of a radically polymerizable monomer such as methyl methacrylate. And a mixture of organopolysiloxanes having the chemical structure 6).

  The pressure-sensitive adhesive film of the present invention can be laminated with a peelable protective film in order to protect the pressure-sensitive adhesive layer and prevent blocking. In this case, as the protective film, any protective film (separator) such as a plastic film such as polyethylene, polypropylene or polyethylene terephthalate, a metal foil such as an aluminum foil or a copper foil, or a laminated film of a plastic film and a metal foil can be used. . Moreover, in order to make peeling of a protective film easy, you may process the surface of a protective film with mold release agents, such as a silicone type and a fluorine type.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

The linear expansion coefficient of the heat resistant film and the weight reduction rate of the pressure-sensitive adhesive in the present invention are measured as follows.
The linear expansion coefficient of the heat-resistant film was raised from room temperature to 250 ° C. using a thermomechanical analyzer (manufactured by Shimadzu Corporation, TMA-60), and further maintained at that temperature for 5 minutes, then 10 ° C./min. The average linear expansion coefficient from 200 ° C. to 50 ° C. during cooling is obtained.

The weight reduction rate of the pressure-sensitive adhesive was determined by removing only the pressure-sensitive adhesive layer from the pressure-sensitive adhesive film applied on the heat-resistant film, and using a simultaneous differential heat / thermogravimetric measuring device (DTG-60, manufactured by Shimadzu Corporation) at room temperature. To 250 ° C. at a rate of 10 / min. The weight reduction rate between 50 ° C. and 200 ° C. is obtained.

Further, the contact angle was measured by the ATAN 1/2 angle method using a measurement temperature of 25 ° C. ± 2 ° C. and an apparatus contact angle meter Model: Simage02V (manufactured by Excimer).

[Example 1]
A polyimide film with a thickness of 25 μm (manufactured by Toray DuPont Co., Ltd .: Kapton 100EN, average linear expansion coefficient of 15 to 50 ppm / K at 50 to 200 ° C.) was charged into a plasma processing apparatus with a vacuum chamber, under an oxygen atmosphere at a pressure of 4.5 Pa The reduced pressure plasma treatment was performed at an applied voltage of 4.5 kV. The dispersion component, dipole component and hydrogen bond component of the surface free energy obtained from the contact angles of water, diiodomethane and ethylene glycol of the polyimide film after the plasma treatment are 17 mN / m, 85 mN / m and 36 mN / m, respectively. The surface free energy was 138 mN / m.

On the polyimide film, a silicone-based condensation curable primer was applied as a primer layer so as to have a thickness of 0.2 to 1 μm after drying and heat-treated at 130 ° C. for 30 seconds. Next, an addition curing type silicone pressure-sensitive adhesive is applied on the polyimide film on which the primer layer is formed so as to have a thickness of 6 μm after drying, and is 30 seconds at 70 ° C., 30 seconds at 100 ° C., and 60 seconds at 130 ° C. Heat treatment was performed, and a PET separator was laminated on the pressure-sensitive adhesive application surface to prepare an adhesive film with a PET separator. The weight reduction rate of 50 to 200 ° C. of the silicone-based adhesive of the present adhesive film was 0.8 wt%.

Next, the obtained adhesive film was bonded to a copper plate having a thickness of 200 μm coated with palladium at 25 ° C. using a laminator, and then, 175 ° C. for 1.5 hours, 200 ° C. for 0.5 hours, and further Heat treatment was performed at 175 ° C. for 6 hours. After the heat treatment, the adhesive film was peeled off from the copper plate coated with palladium in the 90 ° direction and the adhesive strength was measured. The adhesive strength was 1.8 N / cm, and the adhesive strength to the copper plate coated with palladium was measured. The transfer of adhesive from the film (adhesive residue) was not confirmed.

Further, this adhesive film was bonded to a copper lead frame coated with palladium plating at 25 ° C., and after heat treatment at 175 ° C. for 1.5 hours and 200 ° C. for 0.5 hours, the temperature was increased with an epoxy-based sealing resin. Transfer molding was performed at 175 ° C., a pressure of 8 MPa, and a time of 2 minutes. After molding, when leakage of the mold resin to the outer lead portion to which the adhesive film was attached was visually confirmed, occurrence of resin leakage (mold flash) was not recognized.

[Example 2]
A 25 μm-thick polyimide film (manufactured by Toray DuPont: Kapton 100EN) was subjected to reduced-pressure plasma treatment under a carbon dioxide pressure of 20 Pa and an applied voltage of 5.0 kV. The dispersion component of the surface free energy obtained from the water contact angle, the diiodomethane contact angle, and the ethylene glycol contact angle of the plasma-treated polyimide film is 22 mN / m, the dipole component is 53 mN / m, and the hydrogen bond component is 27 mN. The surface free energy was 102 mN / m.

Hereinafter, when carried out in the same manner as in Example 1, the adhesive strength when peeled in the 90 ° direction between the copper plate coated with palladium after heat treatment and the adhesive film was 1.8 N / cm, and after the adhesive strength measurement No adhesive residue was observed on the copper plate coated with palladium. In addition, the lead frame to which the pressure-sensitive adhesive film is bonded is subjected to heat treatment at 175 ° C. for 1.5 hours and 200 ° C. for 0.5 hours, and then the epoxy sealing resin is used at a temperature of 175 ° C., a pressure of 8 MPa, a time of 2 Transfer molding was performed under the condition of minutes. After molding, when leakage of the mold resin to the outer lead portion to which the adhesive film was attached was visually confirmed, occurrence of resin leakage (mold flash) was not recognized.

[Example 3]
The same procedure as in Example 1 was performed except that the primer was changed to the addition-curing type.
After heat treatment, when the adhesive strength was measured by peeling the palladium-coated copper plate and the adhesive film in the 90 ° direction, it was 1.8 N / cm, and the adhesive residue on the palladium-coated copper plate after the adhesive strength measurement was It was not confirmed. In addition, the lead frame to which the adhesive film was bonded was subjected to heat treatment at 175 ° C. for 1.5 hours and 200 ° C. for 0.5 hours, and then with an epoxy-based sealing resin at a temperature of 175 ° C., a pressure of 8 MPa, and a time of 2 minutes. Transfer molding was performed under the conditions. After molding, when leakage of the mold resin to the outer lead portion to which the adhesive film was attached was visually confirmed, occurrence of resin leakage (mold flash) was not recognized.

[Example 4]
It implemented like Example 1 except not having apply | coated the primer.
After the heat treatment, the 90 ° direction of the copper plate coated with palladium and the adhesive film was peeled off and the adhesive strength was measured. As a result, the adhesive strength on the copper plate coated with palladium after measuring the adhesive strength was 1.5 N / cm. It was not confirmed. In addition, the lead frame to which the adhesive film was bonded was subjected to heat treatment at 175 ° C. for 1.5 hours and 200 ° C. for 0.5 hours, and then with an epoxy-based sealing resin at a temperature of 175 ° C., a pressure of 8 MPa, and a time of 2 minutes. Transfer molding was performed under the conditions. After molding, when leakage of the mold resin to the outer lead portion to which the adhesive film was attached was visually confirmed, occurrence of resin leakage (mold flash) was not recognized.

[Example 5]
The same procedure as in Example 2 was performed except that the heat-resistant film was changed to a 50 μm-thick polyimide film (manufactured by Toray DuPont Co., Ltd .: Kapton200EN). The linear expansion coefficient of this polyimide film was 17 ppm / K. The dispersion component of the surface free energy calculated from the contact angle of water of the polyimide film, the contact angle of diiodomethane, and the contact angle of ethylene glycol is 16 mN / m, the dipole component is 98 mN / m, and the hydrogen bond component is 37 mN / m. The surface free energy was 151 mN / m.

After the heat treatment, the 90 ° direction of the copper plate coated with palladium and the adhesive film was peeled off and the adhesive strength was measured. As a result, the adhesive strength on the copper plate coated with palladium after measuring the adhesive strength was 1.6 N / cm. It was not confirmed. In addition, the lead frame to which the adhesive film was bonded was subjected to heat treatment at 175 ° C. for 1.5 hours and 200 ° C. for 0.5 hours, and then with an epoxy-based sealing resin at a temperature of 175 ° C., a pressure of 8 MPa, and a time of 2 minutes. Transfer molding was performed under the conditions. After molding, when leakage of the mold resin to the outer lead portion to which the adhesive film was attached was visually confirmed, occurrence of resin leakage (mold flash) was not recognized.

[Example 6]
It implemented similarly to Example 2 except having changed the heat resistant film into another 25-micrometer-thick polyimide film (Ube Industries, Ltd. product: Upilex25S). The linear expansion coefficient of this polyimide film was 16 ppm / K. The dispersion component of the surface free energy obtained from the contact angle of water of the polyimide film, the contact angle of diiodomethane, and the contact angle of ethylene glycol is 17 mN / m, the dipole component is 107 mN / m, and the hydrogen bond component is 34 mN / m. The surface free energy was 158 mN / m.

After the heat treatment, the 90 ° direction of the copper plate coated with palladium and the adhesive film was peeled off and the adhesive strength was measured. As a result, the adhesive strength on the copper plate coated with palladium after measuring the adhesive strength was 1.6 N / cm. It was not confirmed. In addition, the lead frame to which the adhesive film was bonded was subjected to heat treatment at 175 ° C. for 1.5 hours and 200 ° C. for 0.5 hours, and then with an epoxy-based sealing resin at a temperature of 175 ° C., a pressure of 8 MPa, and a time of 2 minutes. Transfer molding was performed under the conditions. After molding, when leakage of the mold resin to the outer lead portion to which the adhesive film was attached was visually confirmed, occurrence of resin leakage (mold flash) was not recognized.

[Comparative Example 1]
The dispersion component of the surface free energy obtained from the water contact angle, diiodomethane contact angle, and ethylene glycol contact angle of a 25 μm-thick polyimide film (Toray Dupont Co., Ltd., Kapton 100EN) not subjected to plasma treatment is 34 mN / m. The dipole component was 27 mN / m, the hydrogen bond component was 7 mN / m, and the surface free energy was 67 mN / m.
Next, an addition-curing type silicone-based adhesive is applied onto the polyimide film so as to have a thickness of 6 μm after drying, and heat treatment is performed at 70 ° C. for 30 seconds, 100 ° C. for 30 seconds, and 130 ° C. for 60 seconds. An adhesive film with a PET separator was prepared by laminating a PET separator on the adhesive-coated surface.
This adhesive film was adhered to a copper plate coated with palladium at 25 ° C., and the adhesive strength after heat treatment was measured in the same manner as in Example 1. The adhesive strength was 1.1 N / cm, and the adhesive formed on the polyimide film All layers were transferred to a copper plate coated with palladium.

[Comparative Example 2]
A 25 μm-thick polyimide film (manufactured by Toray DuPont Co., Ltd., Kapton 100EN) was subjected to reduced-pressure plasma treatment under an oxygen gas pressure of 4.5 Pa and an applied voltage of 2.0 kV. The dispersion component of the surface free energy obtained from the water contact angle, diiodomethane contact angle, and ethylene glycol contact angle of the polyimide film subjected to the plasma treatment is 25 mN / m, the dipole component is 30 mN / m, and the hydrogen bond component is 19 mN. / M, and the surface free energy was 74 mN / m.
Next, an addition-curing type silicone-based adhesive is applied onto the polyimide film so as to have a thickness of 6 μm after drying, and heat treatment is performed at 70 ° C. for 30 seconds, 100 ° C. for 30 seconds, and 130 ° C. for 60 seconds. An adhesive film with a PET separator was prepared by laminating a PET separator on the adhesive-coated surface.
This adhesive film was adhered to a copper plate coated with palladium at 25 ° C., and the adhesive strength after heat treatment was measured in the same manner as in Example 1. The adhesive strength was 1.1 N / cm, and the adhesive formed on the polyimide film All layers were transferred to a copper plate coated with palladium.

[Comparative Example 3]
A low adhesion type silicone adhesive (addition curing type) is applied to a 25 μm thick polyimide film (Toray DuPont: Kapton 100EN) that has not been plasma-treated so as to have a thickness of 6 μm after drying. Heat treatment was performed for 30 seconds, 100 ° C. for 30 seconds, and 130 ° C. for 60 seconds, and a PET separator was laminated on the pressure-sensitive adhesive coated surface to prepare an adhesive film with a PET separator. The weight reduction rate of this adhesive was 0.8 wt%.
This adhesive film was adhered to a copper plate coated with palladium at 25 ° C., and the adhesive strength after heat treatment was measured in the same manner as in Example 1. As a result, it was 0.26 N / cm. The glue of the adhesive film did not migrate. However, after the lead frame to which the adhesive film is bonded is subjected to heat treatment at 175 ° C. for 1.5 hours and 200 ° C. for 0.5 hours, the epoxy sealing resin is used at a temperature of 175 ° C., a pressure of 8 MPa, and a time of 2 minutes. Transfer molding was performed under the conditions, and after molding, the leakage of the mold resin with respect to the outer lead portion to which the adhesive film was attached was visually confirmed. As a result, occurrence of resin leakage (mold flash) was observed.

  The present invention is an adhesive film for protecting the outer lead portion of a lead frame when sealing a semiconductor package such as QFN, and has an excellent effect that no adhesive residue occurs when re-peeling from a mold flash or a lead frame. And is industrially useful.

Claims (12)

It is an adhesive film for manufacturing a semiconductor consisting of at least a heat-resistant film and an adhesive layer, which is used by being attached to a lead frame in a semiconductor manufacturing process,
The adhesive film for semiconductor manufacture, wherein the surface free energy required by the contact angle method of the heat resistant film is 90 to 160 mN / m. The dispersion component of the surface free energy of the heat-resistant film obtained by a contact angle method using water, diiodomethane and ethylene glycol is 10 to 30 mN / m, the dipole component is 40 to 110 mN / m, and the hydrogen bond component is 20 to 20 It is 40 mN / m, The adhesive film for semiconductor manufacture of Claim 1 characterized by the above-mentioned. 3. The heat-resistant film is an aromatic polyimide film having an average linear expansion coefficient of 50 to 200 ° C. of 10 to 50 ppm / K and a thickness of 5 to 100 μm. Adhesive film for semiconductor manufacturing.   The pressure-sensitive adhesive film for semiconductor production according to any one of claims 1 to 3, wherein the heat-resistant film has been subjected to at least one surface treatment of plasma treatment or corona treatment.   5. The pressure-sensitive adhesive layer according to claim 1, wherein the pressure-sensitive adhesive layer is a pressure-sensitive adhesive layer made of either a peroxide-curing type or an addition reaction-curing type silicone-based pressure-sensitive adhesive composition having a thickness of 1 to 50 μm. The adhesive film for semiconductor manufacture in any one. The pressure-sensitive adhesive layer for semiconductor production according to any one of claims 1 to 5, wherein the pressure-sensitive adhesive layer has a thermal weight reduction rate of 50% or less between 50 and 200 ° C.   The pressure-sensitive adhesive layer is formed on the heat-resistant film whose surface free energy obtained by the contact angle method is 90 to 160 mN / m via a primer layer. The adhesive film for semiconductor manufacture as described. The pressure-sensitive adhesive film for manufacturing a semiconductor according to claim 7, wherein the primer layer contains polyorganosiloxane and is cured by either an addition reaction or a condensation reaction.   The pressure-sensitive adhesive film for manufacturing a semiconductor according to claim 7 or 8, wherein the primer layer has a thickness of 0.01 to 5.0 µm. A method for producing a pressure-sensitive adhesive film for semiconductor production comprising at least a heat-resistant film and a pressure-sensitive adhesive layer used by being attached to a lead frame in a semiconductor production process,
The surface free energy required by the contact angle method of the heat resistant film is 90 to 160 mN / m in advance,
Then, a pressure-sensitive adhesive layer is formed. A method for producing a pressure-sensitive adhesive film for semiconductor production.   The method for producing a pressure-sensitive adhesive film for semiconductor production according to claim 10, wherein the surface free energy obtained by the contact angle method is 90 to 160 mN / m by subjecting the heat resistant film to plasma treatment or corona treatment. . The pressure-sensitive adhesive film for semiconductor production according to claim 10 or 11, wherein a pressure-sensitive adhesive layer is further formed after forming a primer layer on a heat-resistant film whose surface free energy is 90 to 160 mN / m in advance. Production method.