Impact of temperature on RF characteristics and electrical noise analysis of an L-shaped gate tunnel FET with hetero-stacked source configuration

In this article, a pocket doped hetero-stacked L-shaped gate silicon-on-insulator (SOI) tunnel FET (HS-LG-TFET) has been proposed and investigated. The band-to-band tunneling (BTBT) feature of LG-TFET in a direction perpendicular to the channel facilitates higher ON current due to relatively larger tunneling area. The channel appears to be U-shaped that is primarily distributed along the vertical direction, which increases the device scalability. Besides, the HS source architecture owns an upper source layer, which consists of larger bandgap material silicon and an underlying source layer, which consists of smaller bandgap material germanium. This underlying layer of smaller bandgap material in HS-LG-TFET provides enhanced ON current as well as steeper subthreshold swing behavior. The electrical noise behavior of the proposed structure is addressed to test its viability. Furthermore, a complete radio frequency (RF) characterization, including transconductance, capacitances, cutoff frequency, gain bandwidth product, maximum oscillation frequency, transit time, and minimum noise figure of the proposed device are analyzed to examine its analog applicability. Moreover, for checking the reliability issues associated with temperature, the temperature dependence on transfer and RF characteristics are also explored and presented. Further, the non-quasi-static equivalent circuit of the proposed structure is presented to analyze its behavior in the high frequency range.