Impact of a Treatment Combining Nitrogen Plasma Exposure and Forming Gas Annealing on Defect Passivation of SiO2/SiC Interfaces

Heiji Watanabe; Yuu Watanabe; Makoto Harada; Yusuke Kagei; Takashi Kirino; Takuji Hosoi; Takayoshi Shimura; Shuhei Mitani; Yuki Nakano; Takashi Nakamura

doi:10.4028/www.scientific.net/MSF.615-617.525

Paper Titles

Observation of SiC Oxidation in Ultra-Thin Oxide Regime by In Situ Spectroscopic Ellipsometry
p.509

4H-SiC Oxide Characterization with SIMS Using a ¹³C Tracer
p.513

Transient Currents Induced in 6H-SiC MOS Capacitors by Oxygen Ion Incidence
p.517

Electrical Characterization of MOS Structures with Deposited Oxides Annealed in N₂O or NO
p.521

Impact of a Treatment Combining Nitrogen Plasma Exposure and Forming Gas Annealing on Defect Passivation of SiO₂/SiC Interfaces
p.525

Oxidation Process of SiC by RTP Technique
p.529

Analysis of the Electron Traps at the 4H-SiC/SiO₂ Interface of a Gate Oxide Obtained by Wet Oxidation of a Nitrogen Pre-Implanted Layer
p.533

Effect of High Temperature Oxidation of 4H-SiC on the Near-Interface Traps Measured by TDRC
p.537

AlON/SiO₂ Stacked Gate Dielectrics for 4H-SiC MIS Devices
p.541

HomeMaterials Science ForumMaterials Science Forum Vols. 615-617Impact of a Treatment Combining Nitrogen Plasma...

Impact of a Treatment Combining Nitrogen Plasma Exposure and Forming Gas Annealing on Defect Passivation of SiO₂/SiC Interfaces

Abstract:

We propose a treatment combining nitrogen plasma exposure and forming gas annealing (FGA) to improve the electrical properties of SiO2/SiC interfaces. Although conventional FGA at 450°C alone is not effective for reducing interface traps and fixed charges, our combination treatment effectively reduces both even at moderate temperatures. We achieved further improvement by applying our treatment at higher (over 900°C) FGA temperatures, including lower interface state density (Dit) values for both deep and shallow energy levels (1 - 4 x 1011 cm-2eV-1). Considering that nitrogen incorporation promotes hydrogen passivation of interface defects, a possible mechanism for the improved electrical properties is that interface nitridation eliminates carbon clusters or Si-O-C bonds, which leads to the formation of simple Si and C dangling bonds that can be readily terminated by hydrogen. We therefore believe that our treatment is a promising method for improving the performance of SiC-based MOS devices.