Silicon Hybrid Wafer Scale Integration (WSI) Used to Fabricate a Hilbert Transform Integrated Circuit Module

This research was performed in order to develop a superior processing schedule for fabricating Wafer-Scale Integration WSI circuit modules. This technology allows the design of circuitry that spans the entire surface of a silicon substrate wafer. The circuit element employed in this research was the Hilbert transform, a digital phase-shifting circuit. The transform was incorporated into a three Integrated Circuit IC die package that consisted of a mechanically supportive silicon wafer, three IC die, and a planarizing silicon wafer. The die were epoxied into this wafer using a Teflon block as a flat, and the combination was epoxied onto the substrate wafer, forming the IC module. The original design goals this research to keep the IC die and wafer planar and to electrically characterize of the modules interconnects. The first goal was met the resultant process uses a low temperature 50 degrees cure to achieve die- to-wafer planarity of within 5 microns. The second was not met due to the inability to pattern the chosen photosensitive dielectric material. Recommendations for further research included the need to use a stable non-stick surface as a epoxy cure fixture and the need to investigate the photopatternable dielectric material.