ADHESIVE FILM FOR SEMICONDUCTOR, AND SEMICONDUCTOR DEVICE

Abstract

There are provided an adhesive film for a semiconductor including: a conductive layer containing at least one metal selected from the group consisting of copper, nickel, cobalt, iron, stainless steel (SUS), and aluminum, and having a thickness of 0.05 m or more; and an adhesive layer formed on at least one surface of the conductive layer and including a (meth)acrylate-based resin, a curing agent, and an epoxy resin, and a semiconductor device including the above-mentioned adhesive film.

Claims

1. An adhesive film for a semiconductor comprising: a conductive layer containing at least one metal selected from the group consisting of copper, nickel, cobalt, iron, stainless steel (SUS), and aluminum, and having a thickness of at least 0.05 m; and an adhesive layer formed on at least one surface of the conductive layer and including a (meth)acrylate-based resin, a curing agent, and an epoxy resin.

2. The adhesive film for a semiconductor of claim 1, wherein the conductive layer has a thickness of 0.05 m to 10 m.

3. The adhesive film for a semiconductor of claim 1, wherein the conductive layer is a copper layer of 0.1 m to 10 m, a stainless steel (SUS) layer of 0.1 m to 10 m, an aluminum layer of 0.1 m to 10 m, a nickel layer of 0.05 m to 10 m, a cobalt layer of 0.05 m to 10 m, or an iron (Fe) layer of 0.05 m to 10 m.

4. The adhesive film for a semiconductor of claim 1, further comprising a barrier layer formed between the conductive layer and the adhesive layer and having a thickness of 0.001 m to 1 m.

5. The adhesive film for a semiconductor of claim 1, wherein the barrier layer includes at least one selected from the group consisting of titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), stainless steel, a nickel alloy, and a rare earth metal, or oxides thereof, and nitrides thereof.

6. The adhesive film for a semiconductor of claim 1, wherein the (meth)acrylate-based resin includes a (meth)acrylate-based repeating unit containing an epoxy-based functional group, the curing agent includes a phenol resin.

7. The adhesive film for a semiconductor of claim 6, wherein the (meth)acrylate-based resin has a hydroxyl equivalent weight of 0.15 eq/kg or less.

8. The adhesive film for a semiconductor of claim 6, wherein the (meth)acrylate-based resin further includes 2 to 40% by weight of the (meth)acrylate-based functional group containing an aromatic functional group.

9. The adhesive film for a semiconductor of claim 6, wherein a weight ratio of the (meth)acrylate-based resin relative to the total weight of the (meth)acrylate-based resin, the epoxy resin, and the phenol resin is 0.55 to 0.95.

10. The adhesive film for a semiconductor of claim 6, wherein the phenol resin has a softening point of 100 C. or more.

11. The adhesive film for a semiconductor of claim 6, wherein the epoxy resin has a softening point of 50 C. to 120 C.

12. The adhesive film for a semiconductor of claim 1, wherein the adhesive film has a thickness of 0.1 m to 300 m, and a thickness ratio of the conductive layer relative to the adhesive layer is 0.001 to 0.8.

13. A semiconductor device comprising the adhesive film for a semiconductor of claim 1, and a semiconductor element that is in contact with a surface of an adhesive layer of the adhesive film.

14. The semiconductor device of claim 13, wherein the semiconductor device further includes an adherend for bonding with the semiconductor element through a wire bonding or flip-chip method.

15. The semiconductor device of claim 14, wherein the adhesive film for a semiconductor is formed between the adherend and the semiconductor element, or the adhesive film for a semiconductor is formed on a surface opposite to a surface to which the semiconductor element and the adherend are bonded.

16. The semiconductor device of claim 13, wherein the semiconductor device includes two or more semiconductor elements, and at least two of the elements are bonded via the adhesive film for a semiconductor.

17. The adhesive film for a semiconductor of claim 5, wherein the nickel alloy includes an alloy containing nickel and one or more elements selected from the group consisting of carbon, manganese, silicon, sulfur, iron, copper, chromium, aluminum, titanium, molybdenum, and cobalt.

18. The adhesive film for a semiconductor of claim 6, wherein the (meth)acrylate-based resin has a glass transition temperature of 10 C. to 20 C.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0119] FIG. 1 shows an example of a semiconductor device including an adhesive film for a semiconductor according to one embodiment of the present invention.

[0120] FIG. 2 shows another example of a semiconductor device including an adhesive film for a semiconductor according to one embodiment of the present invention.

[0121] FIG. 3 shows still another example of a semiconductor device including an adhesive film for a semiconductor according to one embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0122] Specific embodiments of the invention will be described in more detail by way of the following examples. However, these examples are only to illustrate specific embodiments of the invention, and the scope of the invention is not limited thereto.

Examples 1 to 5: Production of Adhesive Layer and Adhesive Film for Semiconductor

Example 1

[0123] (1) Production of a Solution of an Adhesive Layer

[0124] 57 g of phenol resin KH-6021 (produced by DIC Corp., bisphenol A novolac resin, hydroxyl equivalent weight: 121 g/eq, softening point: 125 C.), which is a curing agent for epoxy resin, 85 g of epoxy resin EOCN-104S (produced by Nippon Kayaku Co., Ltd., cresol novolac type of epoxy resin, epoxy equivalent weight: 214 g/eq, softening point: 83 C.), 425 g of the acrylate resin (KG-3015P), 61.7 g of R972, 0.96 g of DICY, and 0.11 g of 2MAOK were mixed in a methyl ethyl ketone solvent to obtain a solution for an adhesive layer (solid content: 20 wt % concentration).

[0125] (2) Production of Adhesive Film for Semiconductor

[0126] The above produced solution for an adhesive layer was coated onto a release-treated polyethylene terephthalate film (thickness 38 m), and then dried at 110 C. for 3 min to obtain an adhesive film with a thickness of about 9 m.

[0127] Then, the adhesive film was laminated on both surfaces of an about 2 m thick copper foil to produce an adhesive film for a semiconductor with a thickness of about 20 m.

Example 2

[0128] A solution for an adhesive layer (solid content: 20 wt % concentration) was obtained in the same manner as in Example 1, except that KG-3082 was used instead of KG-3015P for the acrylate resin. By using the resulting solution, the adhesive film was laminated on both surfaces of an about 2 m thick copper foil in the same manner as in Example 1 to produce an adhesive film for a semiconductor with a thickness of about 20 m.

Example 3

[0129] An about 0.05 m thick niobium (Nb) oxide layer was formed on one surface of an about 2 m thick copper foil by a sputtering deposition method.

[0130] Then, an adhesive film having a thickness of about 9 m obtained in Example 1 was laminated on the niobium (Nb) oxide layer.

[0131] Similarly, an about 0.05 m thick niobium (Nb) oxide layer was formed on the other surface of the about 2 m thick copper foil by a sputtering deposition method, and the adhesive film having a thickness of about 9 m was laminated.

Comparative Example 1

[0132] The solution for an adhesive layer produced in Example 1 was coated onto a release-treated polyethylene terephthalate film (thickness: 38 m), and then dried at 110 C. for 3 min to obtain an adhesive film having a thickness of 20 m.

Comparative Example 2

[0133] The 0.04 m thick copper layer was formed on the adhesive film having a thickness of about 9 m obtained in Example 1, and the adhesive film having a thickness of about 9 m was laminated again on the copper layer to produce an adhesive film for a semiconductor having a thickness of about 18.4 m.

TABLE-US-00002 TABLE 2 Composition of resin compositions of examples [unit: g] Example 1 Example 2 Curing agent KH-6021 57 57 Epoxy resin EOCN-104S 85 85 Filler R972 61.7 61.7 Acrylate resin KG-3015P 425 KG-3082 425 Curing catalyst DICY 0.96 0.96 2MAOK 0.11 0.11

[0134] KH-6021: Bisphenol A novolac resin (DIC Corp., softening point: about 125 C., hydroxyl equivalent weight: 118 g/eq)

[0135] EOCN-104S: Cresol novolac epoxy (Nippon Kayaku Co., Ltd., epoxy equivalent weight: 180 g/eq, softening point: 90 C.)

[0136] <Filler>

[0137] R 972: Evonik Industries, fumed silica, average particle size 17 nm

[0138] <Acrylate Resin>

[0139] KG-3015P: Acrylic resin synthesized at a composition ratio of butyl acrylate:ethyl acrylate:acrylonitrile:methyl methacrylate:glycidyl methacrylate=41:24:30:2:3 (weight average molecular weight: about 900,000, glass transition temperature: 17 C.)

[0140] KG-3082: Acrylic resin synthesized at a composition ratio of butyl acrylate:acrylonitrile:glycidyl methacrylate:benzyl methacrylate=46:20:6:28 (weight average molecular weight: about 660,000, glass transition temperature: 14 C., hydroxyl equivalent weight: about 0.05 eq/kg)

[0141] <Additive>

[0142] DICY: Dicyandiamide

[0143] 2 MAOK: Imidazole-based hardening accelerator

[0144] 3

Experimental Examples: Evaluation of Electromagnetic Wave Shielding Effect of Adhesive Film for Semiconductor

[0145] (1) Manufacture of Semiconductor Device

[0146] The adhesion films for semiconductors respectively obtained in the examples and comparative examples were attached to a first semiconductor element having a quadrangular shape having one side of 10 mm and a thickness of 80 m under the condition of a temperature of 70 C. The first semiconductor element to which the adhesive film was attached was attached to a BGA substrate under conditions of a temperature of 125 C., a pressure of 1 kg, and a time of 1 s.

[0147] Then, the BGA substrate to which the first semiconductor element was bonded was heat-treated at 125 C. for 1 h with a dryer to thermally cure the adhesive film.

[0148] Subsequently, wire bonding was carried out on the first semiconductor element at a wire diameter 23 m and a pitch of 100 m using a wire bonder (Manufacturer: ShinKawa, product name: UTC-1000) under the following conditions at 150 C.

[0149] (2) Evaluation of Electromagnetic Wave Shielding Effect

[0150] Electric power was applied to the above-produced semiconductor device through a signal source, a near field antenna was positioned on the semiconductor device, and then the intensity (dBm) of the electromagnetic wave obtained from the antenna was measured with 2D scanning using a spectrum analyzer in the range of frequencies of about 1 MHz to 8 GHz.

[0151] The measurement results are shown in Table 3 below.

TABLE-US-00003 TABLE 3 Shielding Efficiency Conductive layer/ (maximum dBm = 10log (mW)) Category barrier layer 10 MHz 10 MHz 10 MHz 10 MHz Example 1 Cu 2 m 115 114 110 118 Example 2 Cu 2 m 115 114 110 118 Example 3 Cu 2 m/0.05 m 115 114 110 118 niobium (Nb) oxide layer*2 Comparative None 106 103 96 112 Example 1 Comparative Cu 0.04 m 103 103 97 114 Example 2

[0152] The adhesive film of the examples exhibited a high modulus at the initial elongation, but a modulus was relatively lowered as the elongation rate increased. As the adhesive film had a low elongation rate at room temperature, it could achieve a high cutting property in the expanding process at low temperatures. It was also confirmed that excellent electromagnetic wave absorption performance could be realized as shown in Table 3 above.

[0153] In particular, in the case of the adhesive film of Example 2, as it had a higher modulus at the initial elongation and a lower elongation rate at room temperature as compared with Example 1, improved cutting properties could be realized in the expanding process at a low temperature.

[0154] More specifically, as shown in Table 3 above, it was confirmed that the adhesive film for a semiconductor of Examples 1 to 3 was configured such that a 2 m thick copper layer was located between the adhesive layers, and thus it improved electromagnetic wave shielding performance by about 6 to 14 dBm in the frequency band of 1 MHz to 8 GHz compared with the comparative examples.

[0155] On the contrary, the adhesive film for a semiconductor of Comparative Example 2 having a structure in which a 0.04 m thick copper layer was located between the adhesive layers was confirmed to have no remarkable difference in electromagnetic wave shielding performance in the frequency band of 1 MHz to 8 GHz compared with the comparative examples. Consequently, it could be seen that in order to improve the electromagnetic wave shielding performance, a conductive layer having a thickness of not less than a predetermined value was required.

[0156] Accordingly, it was confirmed that the adhesive films for semiconductors of Examples 1 to 3 could realize the characteristics that can effectively shield and absorb electromagnetic waves which cause malfunction of the electric element and adversely affect the human body.

[0157] (3) Evaluation of Ion Migration

[0158] The adhesive films for semiconductors of Examples 1 and 3 were laminated on two copper electrodes provided at intervals of 75 m, and then heat-treated at 125 C. for 1 h in this state to thermally cure the adhesive film.

[0159] Subsequently, a voltage of 5.5 V was applied to the copper electrode under the conditions of 85 C. and 85 RH %, and the time required until the electrical resistance value suddenly decreased in a short time equal to a few minutes (occurrence of a short) was measured.

[0160] As a result of the time measurement, it was confirmed that the adhesive film for a semiconductor of Example 1 took 190 h to have a short occur, and that the adhesive film for a semiconductor of Example 3 took 220 hours to have a short occur. Thus, it was confirmed that with the adhesive films of the examples, it was relatively difficult to diffuse atoms or ions of the conductive layer into the adhesive layer owing to the characteristics of the adhesive layer. In particular, the adhesive film for a semiconductor of Example 2 could prevent the diffusion of atoms or ions into the adhesive layer due to the presence of a niobium oxide layer formed on both surfaces of the copper foil layer, and could improve the ionization of the metal of the conductive layer.

EXPLANATION OF SYMBOLS

[0161] 110: package substrate [0162] 112: signal pad [0163] 114: ground contact [0164] 116: circuit pattern [0165] 120: semiconductor element [0166] 122: bonding pad [0167] 125: conductive wire [0168] 130: molding member [0169] 140: adhesive film for semiconductor [0170] 200: package substrate [0171] 201: first semiconductor element [0172] 202: second semiconductor element [0173] 203: ground contact part [0174] 204: conductive wire [0175] 205: molding member [0176] 210: first adhesive film for semiconductor [0177] 220: second adhesive film for semiconductor [0178] 300: package substrate [0179] 301: first semiconductor element [0180] 302: second semiconductor element [0181] 303: third semiconductor element [0182] 304: fourth semiconductor element [0183] 305: fifth semiconductor element [0184] 306: ground contact part [0185] 307: conductive wire [0186] 308: FOW (film over wire) [0187] 310: first adhesive film for semiconductor [0188] 320: second adhesive film for semiconductor [0189] 330: third adhesive film for semiconductor