Investigation of capacitance characteristics in metal/high-k semiconductor devices at different parameters and with and without interface state density (traps)

Abstract

Capacitance vs. voltage (C-V) curves at AC high frequency of a metal-insulator-semiconductor (MIS) capacitor are investigated in this paper. Bi-dimensional simulations with Silvaco TCAD were carried out to study the effect of oxide thickness, the surface of the structure, frequency, temperature and fixed charge in the oxide on the C-V curves. We evaluate also the analysis of MIS capacitor structures by different substrate doping concentrations with and without interface state density at different temperatures (100, 300 and 600 K). These studies indicate that the doping substrate concentration and the traps enormously affect the high-frequency C-V curve behaviour. We also demonstrate that for low and high temperatures, the high-frequency C-V curves behaviour changes, indicating that the capacitance due to the substrate is significantly influenced in these conditions (bias and substrate doping concentration).