Analysis and Improvement of Off-state Current in Biaxially Strained Si Nano p-MOSFET by Virtual Substrate's Doping Control

In biaxially strained p-MOSFET with Si channel, formation of a parasitic parallel channel due to misalignment of energy bands degrades device performance by increasing off-state current. In this paper a new approach has been introduced to eliminate this parasitic channel by increasing the dopant concentration of virtual substrate up to . Using simulation the impact of this method on the parasitic channel has been investigated. According to simulation results, increasing virtual substrate's doping not only provides a high mobility channel but also significantly reduces off-state current more than four orders of magnitude. This method is effective in various channel length and also increases output resistance of the MOSFET.