Using fully-depleted technology, the Loral 256K SOI SRAM has demonstra
ted under worst case SEU and prompt dose testing an LET threshold of a
t least 80 MeVcm ($) over cap 2/mg, and a prompt dose rate upset leve
l of greater then 4E10 rad(Si)/s, respectively, without design hardeni
ng. Total dose testing on transistors fabricated on enhanced bond and
etchback SOI substrates indicates over 100 krad(Si) capability. Togeth
er, these results represent the first description of a fully depleted
SOI technology for all radiation-hardened applications except extreme
total dose.