The observation of negative transconductance effect caused by real-space-transfer of electrons in metal oxide semiconductor field effect transistors fabricated with Ta2O5 gate dielectric

N-channel metal oxide semiconductor held effect transistors (MOSFETs) with Ta2O5 gate dielectric were fabricated. An intrinsic Ta2O5/silicon barrier h eight of 0.51 eV was extracted from the gate current, The effective Ta2O5/s ilicon barrier height including image force barrier lowering is about 0.37 eV with drain to source voltage V-DS ranging from 1.5 V to 4.0 V. Due to th e low barrier height, negative transconductance effect was observed in the linear region, The decrease of drain current is due to the real space trans fer of electrons from the drain terminal to the gate electrode.