Silicon and Silicon Carbide Based Metal-Oxide-Semiconductor Devices Using HfO_2 and SiO_2 Gate Dielectric

摘要

In this paper first time we present a model of calculation of flatband capacitance (C_(FB)) for high-k dielectric material hafnia oxide (HfO_2) as an insulator and silicon carbide (SiC) as a semiconductor material for metal-oxide-semiconductor (MOS) devices. We simulate the capacitance-voltage (C-V) characteristics of the MOS devices with ultrathin oxide using ATLAS, a commercially available TCAD tool from SILVACO. The tool has investigated the effect on C-V characteristics of different oxide thickness and doping concentration of SiO_2 and HfO_2 as insulators and Si and SiC as semiconductor based MOS devices. Excellent agreement was observed over a wide range of oxide thickness and substrate doping for the materials. The C-V characteristics of different polytype of SiC semiconductor also studied for n-type MOS devices.