Tunnel junction abruptness, source random dopant fluctuation and PBTI induced variability analysis of GaAs0.4Sb0.6/In0.65Ga0.35As heterojunction tunnel FETs

We present reliability analysis of the two most critical interfaces in III-V Heterojunction Tunnel FET (HTFET) design: (1) Tunnel Heterojunction is characterized in three-dimensional atomic scale resolution using Atom Probe Tomography. We explore the impact of tunnel junction abruptness and source dopant fluctuations on HTFET performance; (2) Extremely scaled Hi-K gate dielectric (sub-0.8 nm EOT: HfO₂, HfO₂-ZrO₂ bilayer, and ZrO₂)/ III-V channel interface is evaluated using Positive Bias Temperature Instability (PBTI) measurements. HfO₂ based HTFET exhibits superior PBTI performance over ZrO₂ based HTFET and shows lifetime improvement over III-V FinFET.