A novel p-channel flash device with a SiGe layer is proposed, which is based on the analysis made with the simulator MEDICI, to enhance the band-to-band-tunneling current and improve the programming speed. The programming biases of the p-channel flash device can be reduced with an equal programming speed. Simulation results show that more than one hundred times enhancement in the programming speed or 35% reduction of the drain voltage can be achieved in the proposed p-channel flash device with a 40% Ge content in the surface SiGe layer. In addition, a Si-cap layer is inserted between the SiGe and the tunneling oxide to obtain a high-quality interface and to optimize the cell structure.Index Terms-Band-to-band-tunneling-induced hot-electron (BBHE), high programming speed, low-voltage operation, p-channel flash, SiGe.

SiGe employment is, for the first time, proposed to enhance band-to-band-tunneling-induced hot electron injection (BBHE) in a p-channel flash by the analysis made with two dimensional device simulator MEDICI. Simulation results show that more than 100 times enhancement in the programming speed can be achieved in a proposed p-channel flash with 40% Ge in the surface SiGe channel. In addition, a Si-cap layer and HfO 2 tunnel dielectric are also incorporated to improve the interface quality. Up to 1000 times enhancement in BBHE injection programming speed is achieved in the case of a p-channel flash memory with surface SiGe layer and HfO 2 tunnel dielectric.