p-Channel TFET Operation of Bilayer Structures With Type-II Heterotunneling Junction of Oxide- and Group-IV Semiconductors

摘要

We propose a p-channel bilayer TFET composed of an n-type oxide semiconductor (n-OS)/p-type group-IV semiconductor (p-IV) heterostructure, allowing us to realize both n- and p-channel TFET operations under the same device structure. Here, the p-IV side in the heterostructure has a metal-oxide-semiconductor (MOS) gate-stack that modulates the surface potential of the p-IV MOS interface and controls the band-to-band tunneling (BTBT) current under the p-TFET operation. Technology computer-aided design (TCAD) simulation predicts the p-TFET operation with symmetric electrical characteristics to the n-TFET operation. Moreover, we experimentally demonstrate the p-TFET operation of the n-ZnSnO/p-SiGe bilayer device, fabricated on a SiGe-on-insulator substrate, under Si back-gate operation. In addition, both n- and p-TFET operations are observed in an identical device by using the top- and back-gate electrodes.