The M-center in 4H-SiC is a carbon self-interstitial

TL;DR

This study identifies the M-center in 4H-SiC as a carbon self-interstitial, providing a detailed first-principles model that explains its bistability, electronic levels, and annealing behavior, filling a long-standing knowledge gap.

Contribution

The paper offers the first comprehensive model linking the M-center in 4H-SiC to the carbon self-interstitial using advanced calculations and spectroscopy.

Findings

M-center properties match those of carbon self-interstitial

Bistability and reconfiguration kinetics are explained by the model

Electronic levels correspond to experimental observations

Abstract

The list of semiconductor materials with spectroscopically fingerprinted self-interstitials is very short. The M-center in 4H-SiC, a bistable defect responsible for a family of electron traps, has been deprived of a model which could unveil its real importance for almost two decades. Using advanced first-principles calculations and junction spectroscopy, we demonstrate that the properties of M, including bistability, annealing, reconfiguration kinetics, and electronic levels, match those of the carbon self-interstitial.