Method and structure to provide balanced mechanical loading of devices in compressively loaded environments
View Patent ↗An integrated circuit chip mounting structure includes a chip carrier electrically connected to a circuit board with an integrated circuit chip mounted on the chip carrier. In addition, a thermally conductive device is thermally connected to the chip and a set of compressible support members are provided to transmit a portion of an applied compressive load from the thermally conductive device to the chip and chip carrier.
1. An integrated circuit chip mounting structure comprising:
a circuit board;
a chip carrier electrically connected to said circuit board;
an integrated circuit chip mounted on said chip carrier;
a heat spreader having a bottom surface connected to a top surface of said integrated circuit chip, wherein said heat spreader has a top surface, opposite said bottom surface, that is larger in surface area than said top of said integrated circuit chip;
a thermally conductive adhesive on said top surface of said heat spreader;
a thermally conductive device thermally connected to said thermally conductive adhesive;
a rigid frame positioned on said chip carrier, wherein said frame is adapted to impart, on said chip carrier, force transmitted from said thermally conductive device;
spring-loaded alignment posts connected to said thermally conductive device, wherein said spring-loaded alignment posts extend through openings in said circuit board and openings in said frame, wherein said spring-loaded alignment posts comprise springs positioned between tops of said spring-loaded alignment posts and a bottom of said thermally conductive device, and wherein said alignment posts are positioned outside a periphery of said chip carrier; and
compressible support members positioned between said bottom of said thermally conductive device and said frame,
wherein said spring-loaded alignment posts pass through said circuit board, said frame, and said compressible support members, and
wherein said frame contacts said chip carrier, said spring-loaded alignment posts, and said compressible support members.
2. The integrated circuit chip mounting structure according to claim 1 , wherein said frame includes a first portion that extends over said chip carrier and a second portion through which said alignment posts pass.
3. The integrated circuit chip mounting structure according to claim 1 , wherein said compressible support members comprise at least one of springs, tubes of compressible material, and compressible rings.
4. The integrated circuit chip mounting structure according to claim 1 , wherein said frame has an L-shape in cross-section.
5. The integrated circuit chip mounting structure according to claim 1 , wherein said frame comprises one of a continuous and a discontinuous structure.
6. The integrated circuit chip mounting structure according to claim 1 , wherein force transmitted through said conductive device is distributed between said integrated circuit chip and said chip carrier by said compressible support member and said frame.