Method and apparatus for removal of semiconductor chips from hybrid circuits

Claim 2

In the fabrication of circuits on a substrate, a method for removal of elements having top and bottom surfaces from said substrate comprising the steps of: forming a sealed region around the area adjacent to the element to be removed; and simultaneously directing a plurality of jet streams comprising a liquid medium at the area adjacent to the element and within said sealed region of sufficient force such that a portion of the jet streams is deflected by the substrate to a portion of the bottom surface of said element and lifts said element off the substrate.

Claim 3

The method according to claim 1 wherein the liquid medium comprises water and a water soluble oil.

Claim 4

The method according to claim 2 further comprising the steps of, subsequent to the removal of the element, sequentially directing at said area within said sealed region jets of iso-propyl alcohol, de-ionized water and air in order to clean said area.

Claim 5

The method according to claim 1 wherein the number of jet streams of said liquid is four and each of said streams is directed to a respective area adjacent to one of the sides of said element.

Claim 6

The method according to claim 1 wherein the number of jet streams is five with each of four streams directed to a respective area adjacent to one of the sides of said element and the fifth directed to approximately the center of said element.

Claim 7

The method according to claim 1 wherein the initial pressure of the liquid before being directed to said area is within the range 12,000 - 20,000 p.s.i.

Claim 8

The method according to claim 1 wherein the maximum surface pressure exerted on the substrate by said jet streams lies within the range 5,000 - 10,000 p.s.i.

Claim 9

The method according to claim 1 further comprising the step of, prior to directing said jet streams to the substrate, collecting said liquid medium in a sealed container until a desired pressure is reached.

Claim 10

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.

Claim 11

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.

Claim 12

The method according to claim 9 further comprising the steps of, subsequent to the removal of said chip and overlying encapsulant, sequentially directing from within said volume at said area within the sealed region streams of iso-propyl alcohol, de-ionized water and air in order to clean and dry said area.

Claim 13

The method according to claim 9 wherein the number of jet streams is four and each stream is directed to a respective area adjacent to each side of the chip.

Claim 14

The method according to claim 9 wherein the number of jet streams is five with each of four streams directed to a respective area adjacent to each side of the chip and the fifth stream directed to approximately the center of the chip.

Claim 15

The method according to claim 9 wherein the maximum surface pressure exerted on the substrate by said jet streams lies within the range 5,000 - 10,000 p.s.i.

Claim 16

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.

Claim 17

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.

Claim 18

Apparatus according to claim 14 further comprising a container coupled to said nozzle tube and first valve means for controlling the passage of said liquid from said container to said tube.

Claim 19

Apparatus according to claim 15 further comprising means for supplying said liquid to said container and second valve means for isolating said container from said supply means when a desired pressure is reached in said container.

Claim 20

Apparatus according to claim 14 wherein said nozzle surface defines four openings therein arranged in a rectangular pattern.

Claim 21

Apparatus according to claim 14 wherein said nozzle surface defines four openings therein arranged in a rectangular pattern and a fifth opening at approximately the center of said rectangle.

Claim 22

Apparatus according to claim 14 wherein the diameter of the openings is within the range 0.01 - 0.02 inches.

Claim 23

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.

Claim 24

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.