Energy Band Adjustment in a Reliable Novel Charge Plasma SiGe Source TFET to Intensify the BTBT Rate
Mohammad K. Anvarifard, Ali A. Orouji
Abstract
The energy band of a novel Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.7</sub> Ge <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.3</sub> source tunneling field-effect transistor (TFET) is successfully adjusted and sharply bent without any physical formation of metallurgical junction around the source/channel regions. By work function engineering, charge plasma of the hole is created inside the heavily doped n-type source region to convert the device from n-i-n to p-n-i-n. Hence, the reliability of the proposed device will increase during the thermal proceeding of the device. The reduced source bandgap and the electrical creation of metallurgical junction are stated as the principal factors intensifying the band-to-band tunneling (BTBT) rate, thereby increasing the drain current considerably. One of the substantial benefits is the neglectable variation of the leakage current for the proposed device promising a high ON– OFF current ratio. Comparing the proposed structure by the conventional TFET and the p-n-p-n TFET performed based on the simulation results revealed the electrical performance improvement. The significant parameters in terms of ON-current ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{ \mathrm{\scriptscriptstyle ON}}{)}$ </tex-math></inline-formula> , transconductance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${g}_{\text {m}}{)}$ </tex-math></inline-formula> , output conductance ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${g}_{\text {d}}{)}$ </tex-math></inline-formula> , voltage gain ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${g}_{\text {m}}/{g}_{\text {d}}{)}$ </tex-math></inline-formula> , <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{ \mathrm{\scriptscriptstyle ON}}/{I}_{ \mathrm{\scriptscriptstyle OFF}}$ </tex-math></inline-formula> , and trap-assisted tunneling (TAT) component have been successfully improved for the proposed device in comparison with the devices under study in this work. Hence, the suggested device is introduced as a reliable high-performance structure applicable in analog and digital applications.