Appeal No. 2003-0672 Page 6
Application No. 09/151,886
IBM TDB No. NA9001182 teaches using an aluminum nitride ceramic with a
thickness of 60 mils cut to the size of the chip as a heat material that is adhesively
bonded to the back of a silicon chip mounted on a substrate. IBM TDB No. NA9001182
also teaches that current alumina cermamic cannot complete heat removal from the
chips and that the perferred material for the heat sink is aluminum nitride which offers
thermal conductivity close to aluminum metal and a matched thermal expansion
coefficient with the chip. IBM TDB No. NA9001182 does not teach or suggest using a
generally planar thermal dissipation member formed of a thermally conductive,
electrically-nonconductive ceramic aluminum oxide material having a thickness of less
than about 100 mils (2.5 mm) which extends generally coterminously with or within the
margins of the second heat transfer surface of the source.
Kurokawa discloses a high density, high heat dissipating, high reliable package
structure for semiconductor devices. Kurokawa teaches (column 3, lines 20-28) that:
The heat sink can be formed of a single substance material or a
composite material, such as aluminum nitride, aluminum carbide, alumina, boron
nitride, beryllium oxide, silicon, diamond, copper, tungsten, aluminum, since
these materials have a good heat conductivity and therefore are preferable from
the total viewpoint of a heat dissipation property and a connection reliability.
However, the heat sink is in no way limited to the materials mentioned above.
As shown in the drawings, the heat sink is larger than chip. Kurokawa does not teach
or suggest using a generally planar thermal dissipation member formed of a thermally
conductive, electrically-nonconductive ceramic aluminum oxide material having a
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