Impact of Strain and Channel Thickness on Performance of Biaxial Strained Silicon MOSFETs

Abstract

In this paper the impact of strain and channel thickness on the performance of biaxial strained silicon MOSFET with 40 nm channel length has been analyzed by simulation in TCAD Sentaurus Simulator. With the increase in the mole fraction of germanium at the interface of the channel region, the strain in the silicon channel increases and with it the mobility of the carriers increases and thus the drain current increases. The mole fraction in this paper is varied from 0 to 0.3. Other than mobility, the increase in strain also shows improvement in other performance parameters. The impact of variation in channel thickness on the functionality parameters of the MOSFET has also been analyzed. The channel thickness cannot be increased more than the critical thickness and therefore, in this paper the thickness is varied from 2nm to 20 nm. It is observed that beyond 10nm the performance improvement gets saturated and therefore the critical thickness for the channel of this structure is 10nm..