Method and apparatus for removal of semiconductor chips from hybrid circuits

In the fabrication of hybrid circuits on an insulating substrate, a method for removing integrated semiconductor circuit chips bonded to said substrate but slightly raised from the surface of said substrate and having top and bottom surfaces including an encapsulant formed over the chip and substrate comprising the steps of:

• forming a sealed region around the area adjacent to the chip to be removed by contacting the encapsulant with an annular segment of a fixture defining a volume over said chip and substrate;
• collecting a supply of a liquid consisting essentially of water in a sealed container until a pressure within the range 12,000 - 20,000 p.s.i. is reached;
• and
• simultaneously directing from within said volume at least four jet streams of said water supply at the area of encapsulant adjacent to said chip and within said sealed region in a direction essentially perpendicular to said substrate such that each of said streams is directed to a respective area adjacent to each side of the chip, said jet streams having sufficient force such that they bore through said encapsulant and portions of the streams are deflected by the substrate to a portion of the bottom surface of said chip in order to lift said chip and the overlying encapsulant off the substrate.

Apparatus for removal of elements having top and bottom surfaces from a substrate comprising:

• a nozzle head including a bottom surface defining at least four openings therein through which discrete liquid jet streams may be directed;
• a nozzle tube for coupling said liquid to said nozzle head;
• and
• a fixture attached to said tube and defining a volume therein including said nozzle head, said fixture defining an annular opening at a distance from said bottom surface so that said jet streams can pass through.

Apparatus for the removal of integrated circuit chips bonded to an insulating substrate comprising:

• a nozzle head including a bottom surface defining at least four openings therein arranged in a rectangular pattern through which discrete liquid jet streams may be directed;
• a nozzle tube for coupling said liquid to said nozzle head;
• a fixture attached to said tube and defining a volume therein including said nozzle head, said fixture including a segment in the shape of a truncated cone defining an annular opening at a distance from said bottom surface so that said jet streams can pass through;
• a container coupled to said nozzle tube capable of collecting said liquid to a desired pressure and means for releasing said liquid from said container to said tube when the desired pressure is reached;
• and
• means for supplying said liquid to said container and means for isolating said container from said supply means when the desired pressure is reached.