Investigation of the Electrical and Thermal Performance of SOI MOSFETs with Modified Channel Engineering

Abstract

In this paper, we present a novel type of channel doping engineering, using a graded doping distribution, that improves the electrical and thermal performance of silicon-on-insulator (SOI) metal–oxide–semiconductor field effect transistors (MOSFETs), according to simulations that we have performed. The results obtained include a reduction in the self-heating effect, a reduction in leakage currents due to the suppression of short-channel effects (SCEs), and a reduction in hot-carrier degradation. We term the proposed structure a modified-channel-doping SOI (MCD-SOI) MOSFET. The main reason for the reduction in the self-heating effect is the use of a lower doping density near the drain region in comparison with conventional SOI MOSFETs with a uniform doping distribution. The most significant reason for the leakage current reduction in the MCD-SOI structure is the high potential barrier near the source region in the weak inversion state. The SCE factors, including the drain-induced barrier lowering, subthreshold swing, and threshold voltage roll-off, are improved. A highly reliable structure is achieved owing to the lower doping density near the drain region, which reduces the peak electric field and the electron temperature.