This paper proposes a Hetero-Gate-Tri-Oxide Symmetric U-Shaped Tunnel Field-Effect Transistor (HGTO-SUTFET) for ultra-low-power applications. To achieve enhanced electrostatic control and effective suppression of ambipolar conduction, a stacked high-k dual-oxide gate dielectric \(HfO_2\) / \(TiO_2\) and stacked low-k dielectric \(ZrO_2\) / \(TiO_{2}\) are employed near the source and drain regions, respectively. HGTO-SUTFET utilizes p \(^{+}\) doped GaAs and p \(^{+}\) doped Ge as the source and drain materials, respectively, along with an n-type InGaAs channel. This framework enhances the carrier mobility and band-to-band tunneling (BTBT). Besides, an n \(^{+}\) pocket is employed, which enhances the tunneling electric field and achieves improved \(I_{ON}\) of \(4.2\times 10^{-5}\) A/ \(\mu \) m, \(I_{OFF}\) of \(1.38\times 10^{-19}\) A/ \(\mu \) m, an \(I_{ON}\) / \(I_{OFF}\) ratio of \(3.1\times 10^{14}\) , and subthreshold swing (SS) of 4.4 mV/decade. The obtained results confirm that the proposed HGTO-SUTFET exhibits significant potential for low-power, high-speed applications.
