SUPPRESSION OF HOT-CARRIER DEGRADATION IN SI MOSFETS BY GERMANIUM DOPING

Presently there are two approaches to reduce hot-carrier effects in Si MOSFET’s, namely the use of lightly doped drain/double diffused drain (LDD/DDD) structures and the reduction of applied bias. Both of these suffer certain penalties. This letter introduces a novel technique which incorporates Ge impurities in the channel to create additional scattering such that “lucky” hot carriers are less probable. Results indicate that while the initial MOSFET characteristics are maintained, the degradation rate under voltage stress is much reduced. © 1990 IEEE