High temperature resistant bonding solutions enabling thin wafer processing (Characterization of polyimide base temporary bonding adhesive for thinned wafer handling)

Recent advanced devices including packaging and substrates required smart solution for wafer thinning and handling techniques. In addition to 3D-TSV packages, CIS, SiP, power devices, MEMS and SI interposer technologies require thinned substrates without any damage during processing or handling. On the other hand, existing thinning and handling technologies face difficulties when high process temperatures or aggressive chemicals are used in processes for via formation, insulation, via filling and re-routings. We propose the use of high temperature- and chemical-resistant polyimides as both temporary and permanent bonding adhesives in a process sequence called “transfer bonding”; this technology eliminates the difficulty of handling thinned substrates. This paper describes details of the bonding process, several techniques for de-bonding and the potential for applying this technology to manufacture of multiple types of advanced devices.