Total dose hardness of bonded SOI wafers

The response of the buried oxide in bonded and etched-back silicon-on-insulator (SOI) wafers to radiation doses up to 2 Mrad(Si) was measured. The results indicate that the hardness of the buried oxide can be very good, at least that of a good thermally grown oxide, with only small effects from the bond. The amount of charge created in the buried oxide was independent of the thickness of the buried oxide. The buried oxide can easily be made hard enough to prevent back-channel turn-on in nonfully-depleted FETs at doses of at least 2 Mrad(Si). >