Method of packaging an integrated circuit die
View Patent ↗A structure ( 40 ) for holding an integrated circuit die ( 38 ) during packaging includes a support substrate ( 42 ), a release film ( 44 ) attached to the substrate ( 42 ), and a swelling agent ( 60 ). A method ( 34 ) of packaging the die ( 38 ) includes placing the die ( 38 ) on the substrate ( 42 ) with its active surface ( 52 ) and bond pads ( 54 ) in contact with the film ( 44 ). The agent ( 60 ) is applied over an adhesive coating ( 50 ) of the film ( 44 ). The agent ( 60 ) causes the adhesive ( 50 ) to swell into contact with the bond pads ( 54 ) and/or to form fillets ( 64 ) of adhesive ( 50 ) about the die ( 38 ). The die ( 38 ) is encapsulated in a molding material ( 72 ) and released from the substrate ( 42 ) as a panel ( 74 ) of dies ( 38 ). Swelling of the adhesive ( 50 ) about the bond pads ( 54 ) prevents the molding material ( 72 ) from bleeding onto the bond pads ( 54 ).
1. A method of packaging an integrated circuit (IC) die having bond pads located on an active surface of said IC die, said method comprising:
attaching a release film over a support substrate, said release film having an adhesive coating situated on a side of said film opposite said support substrate;
placing said IC die on said support substrate with said active surface in contact with said release film;
applying a swelling agent over said adhesive coating;
allowing said adhesive coating to swell into contact with said bond pads in response to application of said swelling agent;
encapsulating said IC die in a molding material; and
releasing said IC die from said support substrate.
2. A method as claimed in claim 1 further comprising selecting a solvent as said swelling agent.
3. A method as claimed in claim 2 wherein said selecting operation comprises selecting a non-polar solvent as said solvent.
4. A method as claimed in claim 2 further comprising selecting said solvent from a group of solvents that exhibits a boiling temperature in a range of fifty to one hundred and fifty degrees Celsius.
5. A method as claimed in claim 1 further comprising selecting toluene as said swelling agent.
6. A method as claimed in claim 1 further comprising selecting said release film having said adhesive coating formed from a silicone polymer.
7. A method as claimed in claim 1 wherein said applying operation comprises distributing said swelling agent uniformly over said adhesive coating.
8. A method as claimed in claim 1 wherein said applying operation comprises distributing said swelling agent as an atomized spray over said adhesive coating.
9. A method as claimed in claim 1 wherein said applying operation comprises spraying said swelling agent over said adhesive coating at a pressure in a range of 0.5-5 psi.
10. A method as claimed in claim 1 wherein said allowing operation comprises forming a fillet of said adhesive coating about a perimeter of said IC die, said fillet exhibiting a height in a range of approximately one half to one hundred microns.
11. A method as claimed in claim 1 further comprising preventing a flow of said molding material onto said bond pads of said IC die when said adhesive coating swells around at least an active surface of said IC die.
12. A method as claimed in claim 1 wherein said IC die is one of multiple IC dies, each of said multiple IC dies having said active surface, and said method further comprises:
placing each of said multiple IC dies on said support substrate with said active surface facing said release film;
applying said swelling agent over said adhesive coating of said release film;
allowing said adhesive coating to swell into contact with said bond pads on said active surface of said each of said multiple IC dies in response to application of said swelling agent;
concurrently encapsulating said multiple IC dies in said molding material following said applying operation;
releasing said multiple IC dies from said support substrate as a panel following said encapsulating operation; and
separating said multiple IC dies of said panel to form individual IC packages.
13. A structure for temporarily holding at least one integrated circuit (IC) die during packaging thereof, said IC die having bond pads located on an active surface of said IC die, said structure comprising:
a support substrate;
a release film overlying a surface of said support substrate, said release film including a polyimide liner coated with a silicone polymer adhesive coating, wherein said adhesive coating temporarily holds said active surface of said at least one IC die in a desired placement on said support substrate and is swollen by an amount that encapsulates at least said active surface of said IC die in response to application of a solvent adapted to cause swelling of said adhesive coating, said solvent having been uniformly distributed as an atomized spray over said adhesive coating to cause said adhesive coating to swell into contact with said bond pads and encapsulate at least said active surface of said IC die.
14. A structure as claimed in claim 13 wherein said solvent exhibits a boiling temperature in a range of fifty to one hundred and fifty degrees Celsius.
15. A structure as claimed in claim 13 wherein said solvent is a non-polar solvent.
16. A structure as claimed in claim 13 wherein said solvent comprises toluene.
17. A method of packaging an integrated circuit (IC) die having bond pads located on an active surface of said IC die, said method comprising:
attaching a release film over a support substrate, said release film having an adhesive coating situated on a side of said film opposite said support substrate;
placing said IC die on said support substrate with said active surface in contact with said release film;
applying a swelling agent over said adhesive coating by uniformly distributing said swelling agent over said adhesive coating as an atomized spray;
allowing said adhesive coating to swell into contact with said bond pads in response to application of said swelling agent;
encapsulating said IC die in a molding material, wherein when said adhesive coating swells around said IC die, said molding material is prevented from flowing onto said bond pads of said IC die; and
releasing said IC die from said support substrate following encapsulation of said IC die.
18. A method as claimed in claim 17 further comprising:
utilizing said release film having said adhesive coating formed from a silicone polymer; and
selecting a non-polar solvent as said swelling agent.
19. A method as claimed in claim 17 further comprising selecting said solvent from a group of solvents that exhibits a boiling temperature in a range of fifty to one hundred and fifty degrees Celsius.
20. A method as claimed in claim 17 wherein said allowing operation comprises forming a fillet of said adhesive coating about a perimeter of said IC die, said fillet exhibiting a height in a range of approximately one half to one hundred microns.