Leadless integrated circuit package having standoff contacts and die attach pad

1. A method of manufacturing a leadless integrated circuit (IC) package, comprising:

removing portions of a leadframe strip to form recesses defining areas for a die attach pad and a plurality of electrical contacts;

mounting an IC chip in the die attach pad area;

forming electrical connections between the electrical contact areas and the IC chip;

covering the IC chip, the die attach pad area, and the electrical contact areas, and the electrical connections with a molding layer, the molding layer filling the recesses;

forming an etch-resist layer over the electrical contact areas on a bottom surface of the leadframe strip;

selectively etching the bottom surface of the leadframe strip using the etch-resist layer as an etching mask, thereby forming the electrical contacts and the die attach pad as separate components;

wherein the selective etching of the bottom surface of the leadframe strip removes at least a portion of the die attach pad such that a bottom portion of the die attach pad extends away from a bottom surface of the molding layer by a smaller distance compared with bottom portions of one or more of the electrical contacts.

2. The method of claim 1 , further comprising completely removing the die attach pad by performing chemical etching or mechanical grinding on the bottom portion thereof.

3. The method of claim 1 , further comprising:

etching the die attach pad to form a plurality of discrete protrusions in a bottom surface of the die attach pad.

4. The method of claim 1 , further comprising:

forming the etch-resist layer on at least part of a bottom surface of the die attach pad area; and

forming recesses in the die attach pad using the etch-resist layer as an etching mask.

5. The method of claim 1 , further comprising:

applying a solder paste to the die attach pad and the electrical contacts; and

performing a reflow process on the solder to form a plurality of solder bumps.

6. The method of claim 1 , further comprising:

attaching a plurality of preformed solder balls to the electrical contacts and the die attach pad.

7. The method of claim 6 , further comprising:

applying a solder paste or a flux material to the die attach pad and the electrical contacts to aid the attachment of the solder balls.

8. The method of claim 1 , wherein the selective etching of the bottom surface of the leadframe strip thins peripheral portions of the die attach by a greater amount than a central portion of the die attach pad.

9. The method of claim 1 , wherein forming the electrical connections between the electrical contact areas and the IC chip comprises forming wire bonds between the IC chip and the electrical contact areas.