Enhancing the RF/Analog Performance of a Germanium Source Double Gate Ferroelectric Tunnel FET by the Gate Stack Modification Using Different Ferroelectric Materials

Ferroelectric tunnel field effect transistors are well known for their lower supply voltage operation and improved electrostatic characteristics in low power IoT applications. In this article we performed a systematic 2-D Silvaco TCAD simulation based comparative analysis of several RF/Analog parameters of a germanium source double gate ferroelectric tunnel FET using various well known ferroelectric materials on the gate stack of the proposed device. Germanium source form heterojunction with silicon channel at the source channel interface and a heterojunction ferroelectric tunnel FETs may achieve a steep subthreshold swing of 26.7 mV/decade with essentially no ambipolar conduction and a significant increase in ON current when compared to conventional TFETs due to the combined effect of band to band tunneling and negative capacitance. Scaling the ferroelectric layer thickness below its critical thickness can reduce hysteretic losses by stabilizing the negative capacitance effect for ferroelectric polarization. This is ideal for high frequency switching and ultra-low power applications.