Back-Biasing to Performance and Reliability Evaluation of UTBB FDSOI, Bulk FinFETs, and SOI FinFETs

FinFETs and ultrathin body and buried oxide fully depleted silicon on insulator (UTBB-FDSOI) are the main transistors currently used in advanced integrated circuits (ICs). The tunable electrical properties via back-biasing facilitate the threshold voltage adjustment and enable IC designers to achieve a highly efficient and low-power-consuming operation. This study compares the modulation rate before and after hot carrier stress (HCS) of bulk FinFETs, UTBB-FDSOI (tBOX = 20 nm), and SOI FinFETs (t BOX>150 nm) via back-biasing. Simplified back-impedance models are proposed based on the impact of back-biasing on electrical characterization. Additionally, HCS with back-biasing shows a higher impact on UTBB FDSOI than on bulk FinFETs during reliability test, implying that the tBOX plays a critical role in the modulation rate. The lifetime with HCS indicates that the bulk FinFETs exhibit faster downscaling degradation than UTBB FDSOI probably due to the nature of multigate devices whose vertical electrical field should increase faster than planer devices during scaling.