Patent ID: 11569385

Abstract:
An FDSOI device and fabrication method are disclosed. The device comprises: a buried oxide layer disposed on the silicon substrate; a SiGe channel disposed on the buried oxide layer, a nitrogen passivation layer disposed on the SiGe channel layer; a metal gate disposed on the nitrogen passivation layer, and sidewalls attached to sides of the metal gate; and a source and a drain regions disposed on the nitrogen passivation layer at both sides of the metal gate, wherein the source and drain regions are built in a raised SiGe layer. The stack structure of the SiGe layer and the nitrogen passivation layer forms the channel. This stack structure avoids the low stress of the silicon channel in the conventional device. In addition, it prevents the Ge diffusion from the SiGe channel to the gate dielectric in the conventional device. Thereby the invention improves reliability and performance of the device.