Silver bonding wire for BSOB(Bond-Stitch-on-Ball)/BBOS(Bonding-Ball-on-Stitch)

With gradually adopted silver alloy wire bonding in IC and LED Packaging, BSOB becomes a common practice for die stacking in IC packaging and Multi-die Serial Bonding in LED, BBOS is adopted only in LED field. This paper identify a kind of texture of silver alloy bonding wire via Electron Backscatter Diffraction (EBSD) analysis for more consistent BSOB/BBOS bonding with lower MTBA (Mean Time Between Assistant). the key factor is believed to be the anisotropy of the silver bonding wire. Fine tune in Silver alloy doping, adjustment of wire drawing and annealing parameters should be made to achieve this silver alloy bonding wire of high anisotropy nature.