Oxidised porous silicon has been considered as a promising candidate f
or use as a buried oxide in SOI technology. A major advantage it offer
s is that it makes possible the formation of fully isolated SOI struct
ures with a high quality device layer. The paper reports for the first
time, detailed investigation of several important electrical properti
es, such as fixed charge, interface state density, conduction under hi
gh field, and electron trapping, of thermally oxidised porous silicon.