A new bonding-tool solution to improve stitch bondability
A new bonding-tool solution is proposed to improve stitch bondability by creating a new surface morphology on the tip surface of a wire-bonding tool (capillary). The surface has relatively deep lines with no fixed directions. This new capillary has less slipping between the wire and the capillary tip surface and provides better coupling effect between them. Experiments of wire bonding on unstable lead frames/substrates, alloyed wire (2N gold wire) bonding, and copper wire bonding were carried out to confirm the effect of the new capillary on the stitch bondability. The experimental results are promising and have proved that the use of the new capillary could improve the bondability of the stitch bond and minimize the occurrence of short tail defects and non-sticking on lead during bonding.
stitch bondability capillary wire bond copper wire bonding microelectronics packaging