Self-heating-induced spatial spread of interface state generation by hot-electron effect: Role of the high-energy tail electron

The spatial spread of interface states generated by hot-electron effect in the nMOSFET is shown to be significantly increased by self-heating. Substantial generation of interface states in the channel region of the wide-channel strained-Si/SiGe nMOSFET, which suffers from significant self-heating, is observed at a very short stress time. The initial spread of the interface damage is significantly reduced in the narrow-channel strained-Si device, which exhibits a much lesser degree of self-heating. Evidence suggests that the increased spread in the spatial distribution of the interface damage is due to a small fraction of excess "superhot" electrons, which have gained additional energy from phonon absorption.