Method of packaging semiconductor die without lead frame or substrate
A method of packaging a semiconductor die ( 10 ) includes providing a flip-chip die ( 10 ) with bump connections ( 12 ) on its bottom surface ( 14 ). An adhesive tape ( 18 ) is attached to a plate surface ( 16 ) and lead fingers ( 20 ) are formed on the tape ( 18 ). The die ( 10 ) is placed on the tape ( 18 ) such that the bumps ( 12 ) on the die ( 10 ) contact respective ones of the lead fingers ( 20 ) on the tape ( 18 ). A reflow process is performed on the die ( 10 ), the tape ( 18 ) and the plate ( 16 ), which forms C5 type interconnects. A mold compound ( 24 ) is formed over the die ( 10 ) and the tape ( 18 ), and then the tape ( 18 ) and the plate ( 16 ) are removed.
1. A method of packaging a semiconductor die, comprising:
attaching an adhesive tape to a plate surface;
forming lead fingers on the tape;
forming a heat sink on the tape;
providing a semiconductor IC die with bonding pads on a top surface thereof;
placing a bottom surface of the die on the heat sink;
electrically connecting respective ones of the die bonding pads with respective ones of the tape lead fingers with a plurality of wires, wherein the connections of the wires to the lead fingers are ball bonds;
performing a reflow process on the die, the tape and the plate, wherein the ball bonds and the lead fingers melt during the reflow process and form controlled collapse chip carrier connection (C5) type interconnects when cooled;
performing a molding process, wherein a mold compound is formed over the die and the tape; and
removing the tape and the plate such that the heat sink and a surface of the C5 type interconnects are exposed.
2. The method of packaging a semiconductor die of claim 1 wherein the bumps and the lead fingers melt during the reflow process and form controlled collapse chip carrier connection (C5) type interconnects when cooled.
3. The method of packaging a semiconductor die of claim 2 , further comprising grinding the packaged die to expose the C5 type interconnects.
4. The method of packaging a semiconductor die of claim 1 , wherein the adhesive tape is a high temperature tape.
5. The method of packaging a semiconductor die of claim 4 , wherein the tape is able to withstand temperatures greater than about 360° C.
6. The method of packaging a semiconductor die of claim 1 , wherein the bumps are in one of an area array and a peripheral array configuration.
7. The method of packaging a semiconductor die of claim 6 , wherein the die is less than or equal to about 10 mm by about 10 mm in size.
8. The method of packaging a semiconductor die of claim 1 , wherein the lead fingers and the heat sink are formed on the tape by solder cladding.
9. The method of packaging a semiconductor die of claim 8 , wherein the lead fingers have a thickness of about 18 microns.
10. The method of packaging a semiconductor die of claim 1 , wherein the plate is reusable.
11. The method of packaging a semiconductor die of claim 10 , wherein the plate is made of one of copper, ceramic, and stainless steel.
12. The method of packaging a semiconductor die of claim 1 , wherein the die, the tape and the plate are reflowed at a temperature of about 220° C.