Temporary protective film for semiconductor device manufacturing and method for manufacturing semiconductor device

Abstract

To provide a temporary protective film that can be easily peeled off after sealing without loss of adhesive strength after attaching at room temperature.SOLUTION: A temporary protective film for a semiconductor device manufacturing has a support film and an adhesion layer provided on the support film, and the adhesion layer contains polymers containing alkyl(meth)acrylate and (meth)acryloyl morpholine as monomer units and does not contain a cross-linking agent.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a temporary protective film for use in manufacturing a semiconductor device and a method for manufacturing a semiconductor device. [Background technology]

[0002] In semiconductor packages, a structure is sometimes adopted in which an encapsulating layer is formed only on the semiconductor element side of the lead frame, and the back surface of the lead frame is exposed. In manufacturing a semiconductor package having this structure, there is a risk that the encapsulating material will get around to the back surface of the lead frame when the encapsulating layer is formed. To prevent this, a method is known in which a temporary protective film is attached to the back surface of the lead frame (Patent Document 1). The temporary protective film is peeled off from the lead frame after the encapsulating layer is formed. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2001 / 035460 Summary of the Invention [Problem to be solved by the invention]

[0004] It is desirable for a temporary protective film to have an adhesive strength that allows it to be attached to an adherend such as a lead frame at room temperature (25° C.), while being easily peeled off from the adherend after sealing. Therefore, one aspect of the present invention aims to provide a temporary protective film that can be easily peeled off after sealing without losing its adhesive strength after attachment at room temperature. [Means for solving the problem]

[0005] According to the inventors' research, when a polymer containing alkyl (meth)acrylate and (meth)acryloyl morpholine as monomer units is used in the adhesive layer of a temporary protective film, it has been conventionally common to use a crosslinking agent in combination. However, it has been found that by not using a crosslinking agent in combination, the temporary protective film can be easily peeled off after sealing without compromising its adhesive strength after application at room temperature.

[0006] The present invention includes the following aspects. [1] A temporary protective film for use in the manufacture of a semiconductor device, comprising a support film and an adhesive layer provided on the support film, the adhesive layer containing a polymer including alkyl (meth)acrylate and (meth)acryloylmorpholine as monomer units, and not containing a crosslinking agent. [2] The temporary protective film according to [1], wherein the polymer further contains a monomer having an acidic group as a monomer unit. [3] The temporary protective film according to [1] or [2], wherein the thickness of the adhesive layer is 3 μm or less, and the storage modulus of the temporary protective film at 200° C. is 5 MPa or more. [4] A method for manufacturing a semiconductor device comprising the steps of attaching a temporary protective film to one side of a substrate, mounting a semiconductor element on the side of the substrate opposite the temporary protective film, encapsulating the semiconductor element, and peeling the temporary protective film from the substrate, in that order, wherein the temporary protective film comprises a support film and an adhesive layer provided on the support film, and the adhesive layer contains a polymer having alkyl (meth)acrylate and (meth)acryloyl morpholine as monomer units, and does not contain a crosslinking agent. [5] The method according to [4], wherein the polymer further contains a monomer having an acidic group as a monomer unit. [6] The manufacturing method according to [4] or [5], wherein the thickness of the adhesive layer is 3 μm or less, and the storage modulus of the temporary protective film at 200° C. is 5 MPa or more. Effect of the Invention

[0007] According to one aspect of the present invention, it is possible to provide a temporary protective film that can be easily peeled off after sealing without losing its adhesive strength after application at room temperature. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a cross-sectional view showing one embodiment of a temporary protective film. [Diagram 2] 1A to 1C are cross-sectional views illustrating an embodiment of a method for manufacturing a semiconductor device. [Diagram 3] 1A to 1C are cross-sectional views illustrating an embodiment of a method for manufacturing a semiconductor device. [Figure 4] 1 is a cross-sectional view showing an embodiment of a semiconductor device. [Diagram 5] FIG. 2 is a perspective view showing one embodiment of a reel body. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described. FIG. 1 is a cross-sectional view showing a temporary protective film according to one embodiment. As shown in FIG. 1, the temporary protective film 10 according to one embodiment includes a support film 1 and an adhesive layer 2 provided on the support film 1. The temporary protective film 10 can be used as a temporary protective film for manufacturing a semiconductor device. More specifically, the temporary protective film 10 can be used as a temporary protective film for semiconductor encapsulation molding for temporarily protecting the lead frame during encapsulation molding by attaching it to the back surface of the lead frame (the surface opposite to the surface on which the semiconductor element is mounted) in the process of encapsulation molding to form an encapsulation layer that encapsulates the semiconductor element mounted on the die pad of the lead frame.

[0010] The support film 1 may be, for example, a film of at least one polymer selected from the group consisting of polyimide, polyamide, polyamideimide, polysulfone, polyethersulfone, polyphenylene sulfide, polyetherketone, polyarylate, polyetheretherketone, and polyethylene naphthalate, and may be preferably a polyimide film. The polyimide may be an aromatic polyimide. The support film 1 may be a film of copper, aluminum, stainless steel, or nickel. When the support film 1 is a polymer film, its surface may be surface-treated by a method such as a chemical treatment, an alkali treatment, a silane coupling treatment, or the like, a physical treatment, such as a sand mat treatment, a plasma treatment, or a corona treatment.

[0011] The thickness of the support film 1 may be, for example, 5 μm or more, 10 μm or more, 15 μm or more, or 20 μm or more, and may be 100 μm or less, 50 μm or less, or 30 μm or less. The ratio T2 / T1 of the thickness T2 of the adhesive layer 2 to the thickness T1 of the support film 1 may be 0.05 or more, 0.08 or more, or 0.1 or more, and may be 0.5 or less, 0.3 or less, or 0.2 or less.

[0012] The adhesive layer 2 contains a polymer containing alkyl (meth)acrylate and (meth)acryloylmorpholine as monomer units (hereinafter also referred to as "acrylic polymer").

[0013] The alkyl group in the alkyl (meth)acrylate (the alkyl group portion other than the (meth)acryloyl group) may be linear or branched. The number of carbon atoms in the alkyl group may be 2 or more or 3 or more, and may be 30 or less, 20 or less, 10 or less, 7 or less, 5 or less, or 4 or less, or may be 2 or 4.

[0014] Examples of alkyl (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, pentyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, and decyl (meth)acrylate.

[0015] The content of alkyl (meth)acrylate may be 70 mass% or more, 75 mass% or more, or 80 mass% or more, and may be 92 mass% or less, 90 mass% or less, or 88 mass% or less, based on the total amount of monomer units in the acrylic polymer.

[0016] The content of (meth)acryloylmorpholine may be 7 mass% or more, 7.5 mass% or more, 8 mass% or more, 8.5 mass% or more, or 9.0 mass% or more, and may be 20 mass% or less, 18 mass% or less, 17 mass% or less, 16.5 mass% or less, or 16 mass% or less, based on the total amount of monomer units in the acrylic polymer.

[0017] The mass ratio of the (meth)acryloylmorpholine content to the alkyl (meth)acrylate content ((meth)acryloylmorpholine / alkyl (meth)acrylate) may be 0.08 / 1 or more, 0.09 / 1 or more, or 0.1 / 1 or more, and may be 0.3 / 1 or less, 0.25 / 1 or less, 0.23 / 1 or less, 0.21 / 1 or less, or 0.2 / 1 or less.

[0018] The acrylic polymer may further contain other monomers as monomer units in addition to the alkyl (meth)acrylate and (meth)acryloyl morpholine. The other monomers have a polymerizable group that is copolymerizable with the alkyl (meth)acrylate and (meth)acryloyl morpholine. The polymerizable group may be, for example, an ethylenically unsaturated group.

[0019] The other monomer may be a monomer having an acidic group in addition to the polymerizable group. The acidic group may be, for example, a carboxyl group or a sulfo group, and is preferably a carboxyl group. Examples of crosslinkable monomers having a carboxyl group include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, monohydroxyethyl phthalate acrylate, and 2-acryloyloxyethyl succinate.

[0020] Other monomers may be monomers having hydroxyl groups in addition to polymerizable groups.Examples of such monomers include hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, and 12-hydroxylauryl (meth)acrylate; and hydroxyalkyl cycloalkane (meth)acrylates such as (4-hydroxymethylcyclohexyl)methyl (meth)acrylate.

[0021] The content of the other monomers may be 0.1% by mass or more, 0.5% by mass or more, or 1% by mass or more, and may be 5% by mass or less, 4% by mass or less, or 3% by mass or less, based on the total amount of monomer units in the acrylic polymer.

[0022] The weight average molecular weight (Mw) of the acrylic polymer may be 550,000 or more or 600,000 or more, and from the viewpoint of easier peeling of the temporary protective film after sealing, is preferably 650,000 or more, more preferably 750,000 or more, even more preferably 850,000 or more, and particularly preferably 950,000 or more. The Mw of the acrylic polymer may be 2,000,000 or less, 1,800,000 or less, 1,600,000 or less, 1,400,000 or less, 1,200,000 or less, or 1,100,000 or less.

[0023] The molecular weight distribution (Mw / Mn) of the acrylic polymer may be 2.0 or less, 1.9 or less, 1.8 or less, or 1.7 or less, or may be 1.0 or more, 1.2 or more, 1.4 or more, or 1.6 or more.

[0024] The Mw and Mw / Mn of an acrylic polymer are measured by the following procedure. The molecular weight was determined by gel permeation chromatography (GPC) using a high performance liquid chromatograph (Tosoh Corporation, model HLC-8320GPC). Two TSKgel Super Multipore HZ-H (Tosoh Corporation) columns were used, a tetrahydrofuran solution was used as the mobile phase, and a differential refractometer was used as the detector. The measurement conditions were a column temperature of 40°C, a sample concentration of 10mg / mL, a sample injection volume of 10μm, and a flow rate of 0.2mL / min. A calibration curve was created using polystyrene (molecular weights 1,090,000, 775,000, 427,000, 289,000, 190,000, 96,400, 37,900, 10,200, 2,630, and 440) as a standard substance, and the weight average molecular weight (Mw) and number average molecular weight (Mn) were measured. The molecular weight distribution (Mw / Mn) was calculated from the measured values.

[0025] The acid value of the acrylic polymer may be 10 mgKOH / g or more, or 20 mgKOH / g or more, and 40 mgKOH / g or less, or 30 mgKOH / g or less. The hydroxyl value of the acrylic polymer may be 1 mgKOH / g or more, or 2 mgKOH / g or more, and 10 mgKOH / g or less, or 5 mgKOH / g or less. The acid value and hydroxyl value of the acrylic polymer are measured according to the method described in JIS K0070.

[0026] The content of the acrylic polymer, based on the total amount of the adhesive layer 2, may be 80 mass % or more, 85 mass % or more, or 90 mass % or more, and may be 99.5 mass % or less, or 99 mass % or less.

[0027] The adhesive layer 2 does not contain a crosslinking agent. Since the adhesive layer 2 does not contain a crosslinking agent, the adhesive strength of the temporary protective film after application at room temperature is not impaired, and the temporary protective film can be easily peeled off after sealing. In one embodiment, when the adhesive layer 2 does not contain a crosslinking agent, the viscosity of the varnish for forming the adhesive layer 2 can also be suppressed.

[0028] The adhesive layer 2 may further contain other components in addition to the acrylic polymer. Examples of the other components include polymers other than the acrylic polymer and coupling agents.

[0029] The thickness of the adhesive layer 2 may be 1 μm or more, or 2 μm or more, and may be 20 μm or less, 15 μm or less, 10 μm or less, 5 μm or less, 4 μm or less, or 3 μm or less.

[0030] The storage modulus of the temporary protective film 10 at 200° C. may be 0.5 MPa or more or 1 MPa or more, preferably 2 MPa or more, 3 MPa or more, 4 MPa or more, or 5 MPa or more, for example, 10 MPa or less. The storage modulus of the temporary protective film at 200° C. is measured by the method described in the Examples.

[0031] The temporary protective film 10 exhibits a high storage modulus even when the adhesive layer 2 is thin. Specifically, in one embodiment, even when the thickness of the adhesive layer 2 is 3 μm or less, the storage modulus of the temporary protective film 10 at 200° C. can be within the above-mentioned range (particularly, preferably 2 MPa or more, 3 MPa or more, 4 MPa or more, or 5 MPa or more). When the temporary protective film 10 exhibits such a high modulus, wire bonding can be performed neatly.

[0032] In another embodiment, the temporary protective film may further include a cover film provided on the surface of the adhesive layer opposite to the support film. That is, the temporary protective film may include a support film, an adhesive layer, and a cover film in this order. The cover film may be a polyethylene terephthalate film. The thickness of the cover film may be 10 μm or more and 100 μm or less.

[0033] In another embodiment, the temporary protective film may further include a non-adhesive layer provided on the side of the support film opposite to the adhesive layer. The non-adhesive layer may be a resin layer that has substantially no adhesiveness to an adherend at 0 to 270°C. The non-adhesive layer may contain a thermoplastic resin, a thermosetting resin (cured product), or a resin that is a combination thereof. The non-adhesive layer may further contain a filler (e.g., ceramic powder, glass powder, silver powder, copper powder, resin particles, rubber particles), a coupling agent, etc. The thickness of the non-adhesive layer may be 1 μm or more and 10 μm or less.

[0034] The temporary protective film can be produced, for example, by a method including a step of applying a varnish containing an acrylic polymer and a crosslinking agent onto a support film and removing the solvent from the coating to form an adhesive layer.

[0035] Next, a method for manufacturing a semiconductor device using the above-mentioned temporary protective film will be described. The method for manufacturing a semiconductor device according to an embodiment includes, in this order, a step S1 for attaching a temporary protective film to one side of a substrate, a step S2 for mounting a semiconductor element on the surface of the substrate opposite to the temporary protective film, a step S3 for sealing the semiconductor element, and a step S4 for peeling off the temporary protective film from the substrate. Hereinafter, as an example, a method for manufacturing a semiconductor device (semiconductor device package) in which the substrate is a lead frame will be described in more detail.

[0036] 2 is a cross-sectional view illustrating one embodiment (step S1) of a method for manufacturing a semiconductor device. In step S1, as shown in FIG. 2, a temporary protective film 10 is attached to a back surface, which is one surface of a lead frame 11 having a die pad 11a and an inner lead 11b. The temporary protective film 10 is attached in a direction such that an adhesive layer of the temporary protective film 10 contacts the lead frame 11.

[0037] The lead frame 11 may be made of, for example, an iron-based alloy such as alloy 42, copper, or a copper-based alloy. The lead frame 11 may have a molded body made of copper or a copper-based alloy and a coating layer of palladium, gold, silver, or the like that coats the surface of the molded body.

[0038] The temporary protective film 10 has excellent adhesive strength at room temperature (e.g., 25°C), and can be attached to the lead frame 11 at room temperature. The temporary protective film 10 may be attached to the lead frame 11 while being heated and pressed. In this case, the heating temperature may be 150°C or higher and 400°C or lower. The pressure may be 0.5 MPa or higher and 30 MPa or lower. The heating and pressing time may be 1 second or longer and 60 seconds or shorter.

[0039] 3 is a cross-sectional view for explaining one embodiment (steps S2 and S3) of a method for manufacturing a semiconductor device. In step S2, as shown in FIG. 3, a semiconductor element 14 is mounted on the surface of the die pad 11a opposite to the temporary protective film 10. The semiconductor element 14 is bonded to the die pad 11a via an adhesive (for example, silver paste). After bonding the semiconductor element 14 to the die pad 11a, reflow connection (CuClip connection, etc.) may be performed at a maximum temperature of 250 to 440°C or 250 to 400°C for 1 to 30 minutes.

[0040] Next, the semiconductor element 14 is connected to the inner lead 11b using the wire 12. The wire 12 may be, for example, a gold wire, a copper wire, or a palladium-coated copper wire. The wire 12 may be bonded to the semiconductor element 14 and the inner lead 11b using ultrasonic waves and a pressing pressure while being heated at, for example, 200 to 350°C.

[0041] 3, an encapsulating layer 13 is formed to encapsulate the semiconductor element 14 and the wires 12. This results in a temporarily protected encapsulated body 20 having the lead frame 11, the semiconductor element 14, and the encapsulating layer 13.

[0042] The sealing layer 13 is formed by sealing molding using a sealing material. By the sealing molding, a sealed molded body 20 having a plurality of semiconductor elements 14 and a sealing layer 13 that collectively seals them may be obtained. During the sealing molding, the temporary protective film 10 is provided, thereby preventing the sealing material from wrapping around to the back side of the lead frame 11.

[0043] The temperature during the formation of the sealing layer 13 (temperature of the sealing material) may be 140 to 200° C., or 160 to 180° C. The pressure during the formation of the sealing layer may be 6 to 15 MPa, or 7 to 10 MPa. The sealing molding time may be 1 to 5 minutes, or 2 to 3 minutes.

[0044] The sealing material may contain, for example, an epoxy resin such as cresol novolac epoxy resin, phenol novolac epoxy resin, biphenyl diepoxy resin, naphthol novolac epoxy resin, etc. The sealing material may contain a filler, a flame retardant substance such as a bromine compound, a wax component, etc.

[0045] After the formation of the sealing layer 13 (sealing molding), the temporary protective film 10 is peeled off from the lead frame 11 and the sealing layer 13 of the obtained sealed molded body 20. When the sealing layer 13 is cured, the temporary protective film 10 may be peeled off at any time before or after the sealing layer 13 is cured.

[0046] The temperature at which the temporary protective film 10 is peeled off is not particularly limited, but may be room temperature (for example, 5 to 35°C). This temperature may be equal to or higher than the glass transition temperature of the adhesive layer. In this case, the temporary protective film 10 has better peelability from the lead frame 11 and the sealing material. If the Tg of the acrylic polymer in the adhesive layer is, for example, 5°C or lower or 0°C or lower, the Tg of the adhesive layer becomes equal to or lower than room temperature, and good peelability at room temperature is easily obtained.

[0047] When the lead frame 11 includes a plurality of patterns having the die pad 11a and the inner lead 11b, the encapsulated body 20 can be divided as necessary to obtain a plurality of semiconductor devices (semiconductor packages) 100 of Fig. 4 each having one semiconductor element. That is, when the lead frame 11 has a plurality of die pads 11a and a semiconductor element 14 is mounted on each of the plurality of die pads 11a, the manufacturing method according to one embodiment may further include a step of peeling the temporary protective film 10 from the encapsulated body 20 and then dividing the encapsulated body 20 to obtain a semiconductor device (semiconductor package) 100 having one die pad 11a and a semiconductor element 14.

[0048] The temporary protective film may be long and wound around a core in a reel form. In this case, the temporary protective film is attached to the adherend while being unwound from the reel.

[0049] Fig. 5 is a perspective view showing one embodiment of a reel body. As shown in Fig. 5, a reel body 30 according to one embodiment includes a winding core 31, a temporary protective film 10 wound around the winding core 31, and a side plate 32. The width of the winding core 31 and the temporary protective film 10 (the length in the direction perpendicular to the winding direction) may be 1 mm or more, 5 mm or more, or 10 mm or more, and may be 1000 mm or less, 800 mm or less, or 500 mm or less. In another embodiment, the reel body may not include a side plate. EXAMPLES

[0050] The present invention will be described in more detail below with reference to examples, although the present invention is not limited to these examples.

[0051] Example 1 Acrylic polymer A-1 (weight average molecular weight (Mw): 600,000, molecular weight distribution (Mw / Mn): 1.7) containing 80% by mass of butyl acrylate, 16% by mass of acryloylmorpholine, 3% by mass of acrylic acid, and 1% by mass of other monomers (monomers having a hydroxyl group) as monomer units was dissolved in cyclohexanone to obtain a varnish for forming an adhesive layer. A polyimide film (thickness: 25 μm, manufactured by Toray DuPont Co., Ltd., product name: Kapton 100EN) was prepared as a support film. The obtained varnish was applied onto one side of the support film. The coating on the support film was dried by heating at 90°C for 1.5 minutes and at 260°C for 1.5 minutes to form an adhesive layer having a thickness of 2 μm. This resulted in a temporary protective film.

[0052] (Examples 2 to 3) A temporary protective film was obtained in the same manner as in Example 1, except that the thickness of the adhesive layer was changed as shown in Table 1.

[0053] Comparative Example 1 The following formula is used relative to 100 parts by mass of acrylic polymer A-1: [ka] A varnish was prepared by adding 7 parts by mass of a crosslinking agent represented by the following formula: and the thickness of the adhesive layer was changed as shown in Table 1. The same procedure as in Example 1 was repeated to obtain a temporary protective film.

[0054] Example 4 A temporary protective film was obtained in the same manner as in Example 2, except that acrylic polymer A-2 (weight average molecular weight (Mw): 1 million, molecular weight distribution (Mw / Mn): 1.9) containing, as monomer units, 90.5% by mass of butyl acrylate, 5.5% by mass of acryloylmorpholine, 3% by mass of acrylic acid, and 1% by mass of other monomers (monomers having a hydroxyl group) was used instead of acrylic polymer A-1.

[0055] Example 5 A temporary protective film was obtained in the same manner as in Example 4, except that the thickness of the adhesive layer was changed as shown in Table 1.

[0056] (Evaluation of varnish thickening) The adhesive layer varnish used in producing each temporary protective film was evaluated for the presence or absence of thickening. Specifically, 1.1 mL of varnish was used, and the viscosity of the varnish at 25°C was measured on the day the varnish was produced and one month after the production date using a viscosity measuring instrument L type (manufactured by the company). The presence or absence of thickening of the varnish was evaluated according to the following criteria. A: The increase in viscosity of the varnish one month after the date of production is less than 30% compared to the viscosity on the day the varnish was produced. B: The above increase rate is 30% or more, or the varnish has gelled and lost fluidity one month after the date of production.

[0057] (Measurement of storage modulus of temporary protective film) Each temporary protective film was cut into a size of 5 mm x 8 mm to prepare a test specimen. The test specimen was heated at 180°C for 1 hour, then heated at 200°C for 1 hour, and then the storage modulus of the test specimen at 200°C was measured using a dynamic viscoelasticity measuring device (UBM Corporation, Rheogel-E4000). The test specimen was fixed using a jig for shear modulus with a tightening torque of 7 cN·m. The measurement conditions were as follows: measurement mode: frequency dependent, measurement frequency: 20Hz to 600Hz, load: constant control.

[0058] (Measurement of adhesive strength after application at room temperature) A CDA194 palladium-plated plate (PPF, manufactured by Shinko Electric Industries Co., Ltd.) was prepared as a lead frame. Each temporary protective film cut to a size of 10 mm x 50 mm was attached to this lead frame with the adhesive layer in contact with the lead frame using a hand roller under the conditions of 25 ° C. and a load of 20 N. Next, using a force gauge, each temporary protective film was peeled off at a speed of 50 mm / min in a direction of 90 degrees to the main surface of the lead frame at 25 ° C. The maximum load (N / m) per 10 mm width of the adhesive layer at that time was measured as the adhesive strength (90 degree peel strength) after room temperature application. The results are shown in Table 1. If the adhesive strength after room temperature application is 20 N / m or more, it can be said that the adhesive strength is not impaired.

[0059] (Measurement of peel strength after sealing) Using a mold forming machine (manufactured by Apic Yamada Co., Ltd.), a sealing layer was formed on the surface of the lead frame on which the temporary protective film was attached in the same manner as in the above "Measurement of adhesive strength after room temperature application" using a sealing material (product name: GE-300, manufactured by Resonac Co., Ltd.). The sealing conditions were 175°C, 6.8 MPa, and 2 minutes. Then, at 25°C, each temporary protective film was peeled off at a speed of 50 mm / min in a direction of 180 degrees to the main surface of the lead frame, and the peel strength at that time was measured with a force gauge. At this time, the peel strength from the part with a large adhesive area between the temporary protective film and the lead frame was taken as the peel strength on the lead frame, and the peel strength from the part with a large adhesive area between the temporary protective film and the sealing layer was taken as the peel strength on the sealing layer. The smaller the peel strength after sealing, the easier it is to peel off the temporary protective film after sealing.

[0060] [Table 1] [Explanation of symbols]

[0061] Reference Signs List 1: support film, 2: adhesive layer, 10: temporary protective film, 11: lead frame, 11a: die pad, 11b: inner lead, 12: wire, 13: sealing layer, 14: semiconductor element, 20: sealed molded body, 100: semiconductor device.

Claims

1. A support film; an adhesive layer provided on the support film, The temporary protective film for use in the production of a semiconductor device, wherein the adhesive layer contains a polymer containing an alkyl (meth)acrylate and a (meth)acryloylmorpholine as monomer units, and does not contain a crosslinking agent.

2. The temporary protective film according to claim 1 , wherein the polymer further comprises a monomer having an acidic group as a monomer unit.

3. The temporary protective film according to claim 1 or 2, wherein the adhesive layer has a thickness of 3 μm or less, and the temporary protective film has a storage modulus at 200° C. of 5 MPa or more.

4. A step of attaching a temporary protective film to one side of the substrate; Mounting a semiconductor element on a surface of the substrate opposite to the temporary protective film; encapsulating the semiconductor element; peeling the temporary protective film from the substrate; A method for manufacturing a semiconductor device, comprising the steps of: The temporary protective film is A support film; an adhesive layer provided on the support film, The manufacturing method, wherein the adhesive layer contains a polymer containing an alkyl (meth)acrylate and a (meth)acryloylmorpholine as monomer units, and does not contain a crosslinking agent.

5. The method according to claim 4 , wherein the polymer further comprises a monomer having an acidic group as a monomer unit.

6. The method according to claim 4 or 5, wherein the adhesive layer has a thickness of 3 μm or less, and the temporary protective film has a storage modulus at 200° C. of 5 MPa or more.

Images