This work proposes and analyzes a novel Extended Source F-type Nano Field-Effect Transistor (ES-F-NFET). The device features a low bandgap \(\text {Si}_{0.45}\text {Ge}_{0.55}\) source extended toward the drain, which is confined using a wide bandgap material (e.g., SiC) to suppress OFF-state leakage. Device simulations use the Schrodinger–Poisson approach with NEGF for quantum transport. Various Wide Band Gap Materials (WBGm) are evaluated at the drain to study \(I_{\textrm{DS}}-V_{\textrm{gs}}\) characteristics, supported by energy band diagrams, transmission probabilities, and density of states. Along with this, analog/RF performance is assessed through transconductance \((g_m),\) cut-off frequency \((f_t),\) and capacitance metrics. Linearity and reliability are further evaluated using higher-order transconductance \((g_{m3},g_{m2}),\) distortion levels, intercept points \((\text {IIP}_3,\text {VIP}_2,\text {VIP}_3),\) 1-dB compression and \(\text {IMD}_3.\) The ES-F-NFET with \(\text {Si}_{0.45}\text {Ge}_{0.55}\) and SiC as confining material shows superior performance for GaAs-based counterparts at the drain compared to \(\beta \text {-Ga}_2\text {O}_3,\) SiC, and GaN due to better confinement at the interface and wider bandgap.
