Method for forming chip carrier with a single protective encapsulant
AssigneeInternational Business Machines Corporation
InventorsAnson J. Call, Stephen H. Meisner, Frank L. Pompeo, Jeffrey A. Zitz
Life of this patent
Estimating the term…
Abstract
The present invention relates generally to a new apparatus and method for a chip carrier. More particularly, the invention encompasses an apparatus and a method that uses a chip carrier having a single encapsulant to provide both flip chip fatigue life enhancement and environmental protection. A double-sided, pressure-sensitive, thermally-conductive adhesive tape could also be used with the encapsulated chip to directly attach the chip to a heat sink. Similarly, also disclosed is a method and apparatus for directly joining a heat sink to the chip carrier.
Claims17
A method for forming a chip carrier having a single encapsulant, comprising:
- (a) electrically connecting at least one chip to a first surface of a substrate, and forming an electrical connection between said at least one chip and said substrate,
- (b) applying an encapsulant precursor to at least a portion of said electrical connection and to at least a portion of said first surface of said substrate,
- (c) heating said encapsulant precursor to a temperature of about 70.degree. C., .+-.10.degree. C., for a minimum of of about 5 minutes and a maximum of about 15 minutes, until said encapsulant precursor has transformed into a gel,
- (d) heating said encapsulant gel for a minimum of about 1 hour and a maximum of about 2 hours, at a temperature of about 70.degree. C., .+-.10 .degree. C.,
- (e) hardening said encapsulant gel at a temperature of between about 130.degree. C., .+-.10.degree. C., and about 160.degree. C., .+-.10.degree. C., for a minimum of about 4 hours and a maximum of about 6 hours,
- (f) cooling said hardened encapsulant until said hardened encapsulant has reached room temperature, and thereby forming said chip carrier having a single encapsulant.
Dependencies are inferred from the claim text.