Patent ID: 7226811
Filing Date: 2007-06-05
Classification: H01L

Abstract:
1. A process for fabricating a leadless plastic chip carrier, comprising: providing a first metal strip; depositing one of tin and solder on an upper surface and a lower surface of a second metal strip; hot roll solder reflow joining of said first metal strip to said second metal strip, with a solder flux disposed between the metal strips, to solder bond said first metal strip and said second metal strip, thereby forming a leadframe strip; selectively plating at least one of silver, nickel/gold, and nickel/palladium to an upper surface of said first copper strip, in a pattern of at least one row of contact pads; depositing an etch-resist mask on a top surface of said leadframe strip, said portion of said upper surface forming a die attach pad; etching said top surface of said leadframe strip to define at least said die attach pad and said at least one row of contact pads; stripping off said etch-resist mask: mounting a semiconductor die to said die attach pad and wire bonding said semiconductor die to ones of said contact pads; encapsulating said top surface of said leadframe strip in a molding material: stripping said one of tin and solder on said lower surface of said second metal strip; removing said second metal strip; reflowing to separate said one of tin and solder from a bottom surface of the molding material; and singulating the leadless plastic chip carrier from the leadframe strip.