ELO SOI technology for radiation hard devices

It is demonstrated experimentally that thin SOI structures with a predetermined oxide pattern can be made by ELO (epitaxial lateral overgrowth) technology and etchback. It is also demonstrated experimentally that these ELO SOI structures can support MOS devices to a reasonably high level of radiation. At a total dose of 10/sup 6/ rad(SiO/sub 2/), the threshold voltage shift was only -0.17 V, the subthreshold slope change was only 16 mV/decade, and degradation of saturated transconductance was only 4%. At 1*10/sup 7/ rad(SiO/sub 2/), the threshold voltage shift was -0.25 V, the subthreshold slope change was 50 mV/decade, and degradation of saturated transconductance was 18%. This degradation and hence degradation of the device performance at high total dose is due to interface state buildup as a result of irradiation.<
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