DEGRADATION OF SI1-XGEX EPITAXIAL DEVICES BY PROTON IRRADIATION

Irradiation damage in n(+)-Si/p(+)-Si1-xGex/n-Si epitaxial diodes and heterojunction bipolar transistors by protons is studied. The degradat ion of the performance increases with increasing proton fluence, where as it decreases with increasing germanium content and proton energy. T he damage coefficient for proton irradiation is nearly the same as for neutron irradiation and is about three orders of magnitude larger tha n that for electron irradiation. This difference is due to the differe nt number of knock-on atoms and the nonionizing energy loss, which is correlated to the difference of mass and the possibility of nuclear co llisions. (C) 1996 American Institute of Physics.