First-Principles Predictions of Monolayer Violet Phosphorene for Nanoscale Field-Effect Transistor Applications

With the demand for ultrascaled field-effect transistors (FETs), Black Phosphorene (BP) has shown remarkable semiconductor properties but faces significant challenges in ambient stability. The recent synthesis of Violet Phosphorene (VP), an allotrope of BP, opens up possibilities for two-dimensional (2D) pnictogen semiconductors. Here, by first-principles calculations, we systematically evaluated the potential applications of monolayer VP in nanoscale FETs. Our calculations reveal that the VP monolayer possesses superior stability and a larger direct band gap of 2.54 eV compared with the BP monolayer. The full-phonon scattered electron mobility was accurately evaluated to be 382 cm2·V–1·s–1 at room temperature. Quantum transport simulations demonstrate the effective switching performance of the 5.5 nm VP-FETs with the Ion/Ioff exceeding 106 in low-power (LP) applications. Although the VP-FET shows a lower Ion than the BP-FET in LP applications, it achieves a higher Ion in high-performance (HP) applications. Given its superior stability, this work underscores the potential applications of the VP monolayer in nanoscale FETs and broadens the scope of 2D pnictogen as promising channel candidates.