LOW TEMPERATURE INTEGRATION OF CdZnTe(211)B/Si(100) BY WAFER BONDING

摘要

We have successfully integrated CdZnTe (CZT) (211)B with Si (100) by wafer bonding for subsequent epitaxial growth of HgCdTe (MCT). Both direct and indirect wafer bonding methods are presented here. CZT (211)B and Si (100) wafers were directly bonded with good strength. Since the initial CZT surface was rough and uneven, as characterized by atomic force microscopy (AFM) and optical technique, the bonding strength was affected by voids along the bonded interface. To mitigate the surface roughness of CZT wafer, the spin-on-glass (SOG) was used as the intermediate layer to bond CZT with Si at low temperature. The bond strength of the CZT(211)B/SOG/Si(100) was high enough to allow CZT to be back-side polished from 1mm down to about 2μm, and also to withstand thermal cycling with ΔT～400℃. Infrared (IR) transmission images of bonded CZT/Si showed uniform bonding over large surface areas.