Appeal No. 2000-0713
Application 08/864,726
Various methods for providing an adhesive bond between a
heat sink and integrated circuit package are known in the art.
One such method involves positioning an adhesive preform
between the heat sink and integrated circuit package and then
heating the assembly to create a bond. Specification, page 4,
lines 1-7. One of the drawbacks of this method is that air or
gas may be captured between bonding surfaces and the resultant
bubbles present a region of reduced thermal conductivity.
Specification, page 3, lines 11-18 and page 4, lines 7-12. It
is less likely that air or gas will be trapped if a
dispensable adhesive, rather than an adhesive preform is
utilized. Specification, page 4, lines 13-20. However,
dispensable adhesives generally have either poor thermal
characteristics or require special dispensing equipment and
handling. Specification, page 4, line 20-page 5, line 4.
The purpose of the present invention is to provide a
thermoplastic preform adhesive which overcomes the
aforementioned drawbacks of the prior art. Appeal Brief, p.
2. The claimed adhesive preform is shaped such that it has
opposing convex surfaces and a perimeter having concave edges.
Claim 16. Thus, the adhesive preform has a pillow-like shape
in cross-section. Specification, page 10, lines 24-29.
According to appellants:
[a]s a direct result of the configuration of the
present invention, it is now possible to avoid
entrapment of ambient gases or air between the facing
surfaces of the electronic package . . . [and] to
significantly control and/or regulate the flow of
3
Page: Previous 1 2 3 4 5 6 7 8 9 Next
Last modified: November 3, 2007