Z‐shaped gate <scp>TFET</scp> with horizontal pocket for improvement of electrostatic behavior
Sasmita Sahoo, Sidhartha Dash, Soumyaranjan Routray, Guru Prasad Mishra
Abstract
Abstract In this paper, a new Z‐shaped gate TFET structure is proposed with an n+ horizontal pocket insertion beneath the source. The Z‐TFET structure provides higher ON current by 2‐decades as compared to conventional TFET due to the vertical tunneling and presence of HfO 2 gate oxide. Similarly, the ambipolar current reduces by 2‐decades without affecting subthreshold swing (SS) and OFF current significantly. The ON current is further improved by positioning a horizontal pocket layer in the source. The impact of horizontal pocket (HP) concentration and thickness on the analog performance is investigated further using a TCAD device simulator. The simulated results reveal the superiority of the proposed ZHP‐TFET device in terms of ON current (higher by seven times) and average SS (reduces by 13%) as compared to Z‐TFET keeping ambipolar current constant. The ambipolar current can be further reduced by optimizing the length of the back gate. Thus, the proposed device is capable of providing higher I ON /I OFF ( ~10 12 ), I ON /I AMB ( ~10 9 ) ratio, and transconductance with improved average SS of 45 mV/decade.