Bondability and reliability for insulated wirebonding process with 63/spl mu/m pitch capability

In an insulated gold wire bonding process, the understanding of stitch formation and bond reliability are the most challenging areas. In most cases, the eventual stitch pull is low and experiences frequent machine stoppages. This paper presents an innovative approach in wire bonding through special capillary movement to enable mechanical abrasion. The process also involves special capillary surface design to enable effective tearing of the wire insulation material at second bond. Series of evaluation were conducted to establish optimal wire coating thickness with good package reliability on different fine pitch devices