Effects of thermal nitrided gate-oxide thickness on 4H silicon-carbide-based metal-oxide-semiconductor characteristics

Abstract

The effects of thermal nitrided gate-oxide thickness on n-type 4H silicon-carbide-based metal-oxide-semiconductor characteristics have been reported. Seven different thicknesses of oxide (tox), ranging from 2to20nm, have been investigated. It has been shown that effective oxide charge (Qeff) and total interface-trap density (Nit) have demonstrated a cyclic trend as tox is increased. These observations have been explained in the letter. Correlations of Qeff and Nit with oxide breakdown field and current transport mechanism in these oxides have also been established and explained.

Physical characterization of post-deposition annealed metal-organic decomposed cerium oxide film spin-coated on 4H-silicon carbide

“…Intensive studies have been carried out on SiC MOS-based devices and it is crucial to have a high quality gate oxide deposited or grown between a metal electrode and a SiC substrate. NitridedSiO 2 has been widely employed as gate oxide in SiC MOS-based high power devices, owing to its low interface and slow trap densities, high reliability, and low leakage current [7][8][9][10][11][12][13][14][15][16][17][18][19]. Nevertheless, the maximum permissible electric field in SiC-based devices is restricted by the nitrided-SiO 2 due to its low dielectric constant (k = 3.9) compared to SiC (k = 9.7), as scaled by the Gauss's law at the interface [20].…”

Investigation of sol–gel derived HfO2 on 4H-SiC

“…This voltage shift indicates the accumulated effective charge in the oxide. The effective oxide charge and slow-trap density have been calculated using the following equations [2]:…”

“…In order to realize this, a high quality gate oxide must be deposited or grown in between a metal electrode and SiC. Currently, nitrided SiO 2 is considered as the best gate oxide that has been grown on SiC, owing to its low interface-and slow-trap densities [2]. However, this type of oxide could not withstand high electric field (E) as it would breakdown electrically before the SiC substrate does.…”

Effects of heat treatment in vacuum on the physical properties of thermal nitrided silicon dioxide gate on 4H-silicon carbide

“…Besides, SiC has become a favored material compared to other premier wide-bandgap semiconductors due to commercial availability substrates, known device processing techniques, and ability to grow native oxide that is silicon dioxide (SiO 2 ) [1,2,4]. In other words, SiC can be produced in much the same way as silicon but with higher processing temperatures.…”