Gold-Gold (Au-Au) thermocompression (TC) bonding of very large arrays

The authors demonstrate a technique, very large array bonding (VLAB), that extends Au-Au TC bonding from a single connection or tens of connections, to thousands or tens of thousands of connections over a large area in a single joining cycle. A description of a semi-isostatic gas pressure press developed for joining metal and/or metal/polymer arrays onto ceramic or silicon substrates is presented. Bond yields of 99.97% for metal/polyimide thin film arrays containing nearly 60000 contacts to pads on a 127-mm ceramic substrate have been achieved