3D Cryogenic Interposer for Quantum Computing Application

Conventional Cu through silicon via (TSV) (5×50 μm) with Al metal lines on 300mm Si substrate were fabricated and electrically tested at cryogenic temperatures down to 20mK in a dilution refrigerator to assess their reliability for cryogenic applications. I-V characterization of the Al lines was also performed from room temperature to 20mK to study the superconducting transition temperature (Tc) of the A1.