Ultrathin glass wafer lamination and laser debonding to enable glass interposer fabrication

Interposer fabrication processes are applied in three-dimensional (3-D) integrated circuit (IC) integration to shorten the interconnection among different stacked chips and substrates. Because Si is a common material in semiconductor technology, Si interposers have been widely studied in many research activities. Compared with a Si wafer, glass substrates have the advantages of high resistivity, low dielectric constant, low insertion loss, adjustable coefficient of thermal expansion (CTE), and the possibility to use panel-size substrates as well as thin glass substrates (100 µm) to avoid the costly thinning process for realization of low-cost 2.5-D ICs. Thus, glass interposer fabrication is studied thoroughly in this paper.