Hybrid Assembly Module

Hybrid Assembly Module

       A low-cost ceramic package is described which is to be
used as a rigid carrier for passive superchip (passive silicon
carrier) assemblies.  The module uses metallized ceramic layers that
do not require any interconnections.  The multilayer structure is
fixed to form one rigid part by means of the pins serving as
connections to the next packaging level.  The passive superchip (PSC)
is connected to the hybrid assembly substrate by wire bonding or TAB
(Tape Automated Bonding).  If required, the module can be sealed
hermetically.

      As shown in the figure, the hybrid assembly module consists of
layers 1 and 2 of metallized ceramic with fan-out wiring 4 and 5.  A
row of outer lead bond pads 6 and 7 is connected to pin pads 8
and 9 by signal wires of chrome-copper-chrome.  A hole in the center
of the pin pads holds pin 10 which is connected to the pin pad by
soldering. The pins can be flush pins if the area under the passive
superchip is required for them.  Lower ceramic layers are connected
to pins through larger holes in the upper deck to allow pin punching
and soldering.  The various ceramic layers are merely held together
by the pins linking the top deck.
      The hybrid assembly has the following advantages:
      -    Two metallized ceramic plates can be individually
          personalized without reference to each other (like
          matching lay-ups).
      -    The two layers are...