High-temperature characteristics of high-quality SiC MIS capacitors with O/N/O gate dielectric

Abstract

This paper reports the high temperature (up to 450/spl deg/C) characteristics of 6H-SiC MIS capacitors made with SiO/sub 2//SiN/SiO/sub 2/ (ONO) stack gate dielectric deposited by the jet vapor deposition (JVD) process. This ONO stack gate dielectric provides: (1) high immunity to instability caused by mobile ions, (2) orders of magnitude lower gate leakage current than its thermal oxide counterpart, (3) the highest dielectric breakdown strength ever reported for SiC MIS structures at elevated temperatures (i.e., greater than 12 MV/cm at 450/spl deg/C), (4) relatively symmetric p-and n-type C-V and current-voltage (I-V) characteristics, due to low densities of dielectric charge as well as interface traps in both types of samples, and (5) over ten years of projected lifetime for both types operating at an electric field of 3 MV/cm at 350/spl deg/C. The key factors contributing to such success are briefly discussed.