Evidence of substrate enhanced high-energy tails in the distribution function of deep submicron MOSFETs by light emission measurements

This letter reports direct experimental evidence that the high-energy tail of the hot carrier luminescence distribution of deep submicron silicon MOSFETs is essentially modified by the application of a substrate voltage. The bias and temperature dependence of the phenomenon are consistent with an enhancement of the high-energy tail of the energy distribution due to a second impact ionization event occurring at the drain to substrate junction.