Claims
- 1. A method for rapidly bonding a small electronic component having a mating surface smaller than about one square inch selected from the class consisting of capacitor,
- (a) cutting a continuous ribbon having a thickness of 25 to 125 micrometers of non-olefinic, substantially amorphous, solvent-free thermoplastic polymer, the polymer being further characterized in that
- T.sub.g is at least 30.degree. C.
- T.sub.b is below -30.degree. C.
- S.sub.w is less than 1.0% wt. and
- extractable tonics are less than 10 ppm by wt.,
- such that the cut ribbon forms the adhesive pad having both lateral dimensions substantially equal to or greater than the electronic component to be bonded;
- (b) heating mating surfaces of the electronic component and substrate so that the temperature of at least one of the surfaces exceeds the T.sub.g of the adhesive pad;
- (c) positioning the adhesive pad upon the heated substrate with an application of slight pressure to effect heat transfer from the substrate to the adhesive pad, thus softening the adhesive without incurring adhesive flow;
- (d) positioning the small electronic component upon the heated adhesive pad resulting in assembly of the electronic component, adhesive pad and substrates;
- (e) laminating the small electronic component to the substrate by applying a higher pressure to the small electronic component to reduce the thickness of the adhesive pad by 0.5 to 3% followed by a release of pressure within about 5 seconds.
- 2. A method for rapidly bonding a small electronic component having a mating surface smaller than about one square inch selected from the class consisting of capacitor, transistor, resistor, diode and integrated circuit chip to a substrate employing an adhesive pad between the electronic component and the substrate comprising the steps of:
- (a) cutting a continuous ribbon having a thickness of 25 to 125 micrometers of non-olefinic, substantially amorphous, solvent-free thermoplastic polymer, the polymer being further characterized in that
- T.sub.g is at least 30.degree. C.
- T.sub.b is below -30.degree. C.
- S.sub.w is less than 1.0% wt. and
- extractable ionics are less than 10 ppm by wt.,
- such that the cut ribbon forms the adhesive pad having both lateral dimensions substantially equal to or greater than the electronic component to be bonded;
- (b) heating mating surface of the electronic component to near the bonding temperature and heating the substrate so that the temperature exceeds the T.sub.g of the adhesive pad;
- (c) positioning the adhesive pad upon the heated substrate with an application of slight pressure to effect heat transfer from the substrate to the adhesive pad, tush softening the adhesive without incurring adhesive flow;
- (d) positioning the small electronic component upon the heated adhesive pad resulting in assembly of the electronic component, adhesive pad and substrates whereby the heating for steps (b), (c) and (d) is about one second;
- (e) laminating the small electronic component to the substrate by applying a higher pressure to the small electronic component to reduce the thickness of the adhesive pad by 0.5 to 5% followed by a release of pressure within about 5 seconds.
- 3. The method of claim 1 or 2 in which the substrate and small electronic component are heated by direct heat transfer from inert hot gases.
- 4. The method of claim 1 or 2 in which the small electronic component is an integrated circuit chip.
- 5. The method of claim 4 in which the substrate is a metallic lead frame.
- 6. The method of claim 1 in which the substrate is a ceramic oxide.
- 7. The method of claim 1 or 2 in which the adhesive is comprised of a compliant polymer having a low unfilled tensile modulus, T.sub.g below 140.degree. C. and viscosity of less than 1 M Pa.s at the lamination temperature.
- 8. The method of claim 10 in which the adhesive is comprised of a mixture of compliant and rigid polymers.
- 9. The method of claim 2 in which the adhesive is comprised of a rigid polymer having a high unfilled tensile modulus, T.sub.g at least 140.degree. C. melting temperature at least 230.degree. C. and viscosity of less than 5200 Pa.s at the lamination temperature.
- 10. The method of claim 9 in which the adhesive is comprised of a mixture of compliant and rigid polyers.
- 11. The method of claim 1 or 2 in which the polymer adhesive is filled with finely divided particles of heat-conductive solids.
- 12. The method of claim 1 or 2 in which the adhesive is filled with finely divided particles of electrically conductive solids.
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation of copending application Ser. No. 07/853,879 filed Mar. 18, 1992, now abandoned, which is a continuation of application Ser. No. 07/631,263 filed Dec. 12, 1990, now abandoned, which is a continuation of application Ser. No. 07/469,812 filed Jan. 23, 1990, now abandoned, which is a continuation-in-part of application Ser. No. 07/171,974 filed Mar. 23, 1988, now abandoned, which is a continuation-in-part of application Ser. No. 07/088,141 filed Aug. 21, 1987, now abandoned, which is a continuation-in-part of application Ser. No. 07/031,793 filed Mar. 3, 1987, now abandoned.
US Referenced Citations (25)
Foreign Referenced Citations (8)
Number |
Date |
Country |
0051165 |
Oct 1981 |
EPX |
51165 |
May 1982 |
EPX |
0135416 |
Jul 1984 |
EPX |
0142783 |
Nov 1984 |
EPX |
0198194 |
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514007 |
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JPX |
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WOX |
Non-Patent Literature Citations (2)
Entry |
Modern Plastics Encyclopedia, Oct. 1983, vol. 60, No. 10 A, pp. 472-473. |
Heat-Resistant Materials for Electric and Electronic Uses, Hanai, and Hirata, Yuki Gosei Kagaku Kyokai, Shi 42, No. 11: 1074-80, 1984. |
Continuations (3)
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853879 |
Mar 1992 |
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Parent |
631263 |
Dec 1990 |
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469812 |
Jan 1990 |
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Continuation in Parts (3)
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171974 |
Mar 1988 |
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88141 |
Aug 1987 |
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Parent |
31793 |
Mar 1987 |
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