Method of fabricating an integrated circuit (IC) package having a plurality of spaced apart pad portion

Patent metadata

Field	Value
Publication number	US-9520306-B2
Application number	US-201213618509-A
Country	US
Kind code	B2
Filing date	Sep 14, 2012
Priority date	Jun 10, 1998
Publication date	Dec 13, 2016
Grant date	Dec 13, 2016

Abstract

A process for fabricating an integrated circuit package includes selectively etching a leadframe strip to define a die attach pad and a plurality of contact pads. At least one side of the die attach pad has a plurality of spaced apart pad portions. A semiconductor die is mounted to the die attach pad and wires are bonded from the semiconductor die to respective ones of the contact pads. A first surface of the leadframe strip, including the semiconductor die and wire bonds, is encapsulated in a molding material such that at least one surface of the leadframe strip is exposed. The integrated circuit package is singulated from a remainder of the leadframe strip.

First claim

What is claimed is:

1. A process for fabricating an integrated circuit package, comprising:
providing a leadframe strip having an upper surface and a lower surface;
applying an etch-resist mask to the upper and lower surfaces;
patterning the etch-resist mask to expose portions of the upper and lower surfaces;
selectively etching both the upper and lower surfaces of the leadframe strip by completely etching through portions of the leadframe strip to define a die attach pad and a plurality of contact pads, and only partially etching through portions of the leadframe strip to form a plurality of spaced apart pad portions on the lower surface;
mounting a semiconductor die to said die attach pad;
wire bonding said semiconductor die to respective ones of said contact pads;
encapsulating the upper surface of said leadframe strip, said semiconductor die, and wire bonds in a molding material, the lower surface of said leadframe strip being exposed; and
singulating said integrated circuit package from a remainder of said leadframe strip.

2. The process according to claim 1 , wherein said selectively etching comprises selectively etching such that said plurality of pad portions are shaped and oriented to inhibit entrapment of air during encapsulation.

3. The process according to claim 1 , wherein said selectively etching comprises selectively etching said leadframe strip to define a continuous portion on a first side of the die attach pad and said plurality of pad portions extending from the continuous portion to a second side of the die attach pad.

4. The process according to claim 3 , wherein mounting said semiconductor die comprises mounting said semiconductor die to said first side of the die attach pad.

5. The process according to claim 4 , wherein said selectively etching comprises selectively etching to provide said plurality of pad portions wherein each of said pad portions have a generally square cross-section.

6. The process according to claim 4 , wherein said selectively etching comprises selectively etching to provide said plurality of pad portions wherein each of said pad portions have a generally circular cross-section.

7. The process according to claim 5 , wherein said selectively etching comprises selectively etching to provide said pad portions in a diamond pattern such that sides of said pad portions form an oblique angle with sides of said molding material.

8. The process according to claim 1 , wherein the pad portions form an array.

9. The process according to claim 1 , wherein said selectively etching comprises selectively etching to provide said die attach pad such that each of said plurality of pad portions have a generally square cross-section.

10. The process according to claim 1 , wherein said selectively etching comprises selectively etching to provide said die attach pad such that each of said plurality of pad portions have a generally circular cross-section.

11. The process according to claim 9 , wherein said selectively etching comprises selectively etching to provide said pad portions in a diamond pattern in which sides of said pad portions are at an oblique angle with sides of said molding material.

12. The process according to claim 1 , further comprising applying solder paste to the plurality of contact pads and to said at least one side of said die attach pad.

Assignees

• Lin Geraldine Tsui Yee
• De Munnik Walter
• Kwan Kin Pui
• Lau Wing Him
• Tsang Kwok Cheung
• Fan Chun Ho
• Mclellan Neil
• Utac Headquarters Pte Ltd

Inventors

• Lin Geraldine Tsui Yee
• De Munnik Walter
• Kwan Kin Pui
• Lau Wing Him
• Tsang Kwok Cheung
• Fan Chun Ho
• Mclellan Neil

Classifications

• H10W72/5522

  comprising gold [Au] · CPC title

• H10W74/00

  Encapsulations, e.g. protective coatings · CPC title

• H10W72/0198

  batch processes · CPC title

• H10W72/075

  of bond wires · CPC title

• H10W72/073

  of die-attach connectors · CPC title