Patent ID: 6415975
Filing Date: 2002-07-09
Classification: B23K

Abstract:
A system for determining quality of bonding between a conductive ball comprised of a first conductive material and a conductive pad comprised of a second conductive material within an IC package, the system comprising:an intermediary material formed from said first conductive material of said conductive ball and said second conductive material of said conductive pad for bonding said conductive ball to said conductive pad when said conductive pad is bonded to said conductive ball; a bath of etching solution for etching said intermediary material between said conductive ball and said conductive pad such that said conductive ball is decoupled from said conductive pad, said conductive ball having a first color in areas where said intermediary material was not abutting said conductive ball and having a second color in areas where said intermediary material was abutting said conductive ball when said conductive ball was bonded to said conductive pad; and wherein said intermediary material was abutting said conductive ball on an intermediary material area of said conductive ball when said conductive ball was bonded to said conductive pad; a lead frame strip of said IC package with said conductive ball being coupled via a wire to said lead frame strip of said IC package, and wherein said pad is disposed on an IC (integrated circuit) die supported by a die frame dap of said IC package, and wherein said die frame dap with said IC die thereon is cut away from said lead frame strip such that said conductive ball is floating via said wire that is coupled to said lead frame strip; a microscope for capturing a magnified image of said intermediary material area on said conductive ball with said intermediary material area being substantially centered within said magnified image while said conductive ball is decoupled from said conductive pad; and wherein said intermediary material area appears as said second color within said magnified image and wherein an area of said conductive ball wherein said intermediary material was abutting said conductive ball appears as said first color within said magnified image; and a data processor including a computer-readable medium having computer-executable instructions for analyzing said magnified image of said intermediary material area on said conductive ball to determine quality of bonding between said conductive ball and said conductive pad.