Embedded chip fabrication technique for novel hybrid packaging

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Embedded chip fabrication technique for novel
hybrid packaging
This project concerns the embedding of active and
passive devices for advanced RF/Microwave/Millimet
er Wave system on chip applications. We are
currently designing novel self packaging
structures which exhibit characteristics that are
useful for low-cost, high volume production of
practical RF/Microwave/Millimeter-Wave devices.
substrate
Thin film metal
This schematic shows the final aim of the
project several chips embedded in a substrate,
with electrical contact between chips at the
front surface.
Filler material
Embedded chip
This photo shows aluminum CPW lines crossing an
embedded chip, to test the interconnect losses
due to the filler material. This device was
fabricated using an adhesive film to temporarily
hold the chip in place during chip alignment and
filler dispense and cure.
Experiments are currently ongoing on the use of
an evaporated hot melt adhesive layer as
temporary bond promoter. It is proposed that thin
film heaters be used to melt the wax layer during
chip alignment. Solidification of the wax will
then provide a temporary adhesive to hold the
chip during filler dispense and cure.
This photo is a plan view through a
chip-wax-substrate sandwich. It shows a
wax-coated thin film heater (bright thin lines)
on a glass substrate, bonded to a glass chip. The
central shaded area is the wax bond interface.
This area is 0.3mm2.
Paul Rainey