Thickness dependent integrity of gate oxide on SOI

To investigate the gate oxide integrity for the silicon-on-insulator (SOI) wafer, we evaluated the time-dependent dielectric breakdown (TDDB) characteristic of gate oxide formed on SOI wafer with gate oxide thickness (Tox) as a parameter. The TDDB characteristic was degraded with increasing the Tox of gate oxide for the SOI wafer. The time to 50% failure of breakdown (TBD) was shorter when Tox was thicker than 7 nm in contrast to the gate oxide for the bulk silicon wafer.