TEMPERATURE-DEPENDENCE OF MOSFET SUBSTRATE CURRENT

Hitherto, theoretical models for MOSFET substrate current predicted that substrate current is a strong function of temperature. However, experimental data presented in this and previous studies show that the ratio of substrate current to drain current is insensitive to temperature over the range 77 to 300 K. We propose a modified model for an electron mean-free path (MFP) in the substrate current based on the concept of energy relaxation. The difference between the energy and momentum relaxation MPF is clarified and the substrate current model with modified MFP can explain the temperature dependence of the substrate current.