Black Phosphorus Based Field Effect Transistors with Simultaneously Achieved Near Ideal Subthreshold Swing and High Hole Mobility at Room Temperature

Abstract

Black phosphorus (BP) has emerged as a promising two-dimensional (2D) material for next generation transistor applications due to its superior carrier transport properties. Among other issues, achieving reduced subthreshold swing and enhanced hole mobility simultaneously remains a challenge which requires careful optimization of the BP/gate oxide interface. Here, we report the realization of high performance BP transistors integrated with HfO2 high-k gate dielectric using a low temperature CMOS process. The fabricated devices were shown to demonstrate a near ideal subthreshold swing (SS) of ~69 mV/dec and a room temperature hole mobility of exceeding >400 cm2/Vs. These figure-of-merits are benchmarked to be the best-of-its-kind, which outperform previously reported BP transistors realized on traditional SiO2 gate dielectric. X-ray photoelectron spectroscopy (XPS) analysis further reveals the evidence of a more chemically stable BP when formed on HfO2 high-k as opposed to SiO2, which gives rise to a better interface quality that accounts for the SS and hole mobility improvement. These results unveil the potential of black phosphorus as an emerging channel material for future nanoelectronic device applications.

Phosphorene/rhenium disulfide heterojunction-based negative differential resistance device for multi-valued logic

“…1f). Based on the obtained KPFM results and the previously reported band properties (conduction band minimum, valence band maximum and band gap ( E g )) of BP and ReS 2 (refs 42, 43, 44), we graphically described the predicted energy band alignment of the BP and ReS 2 heterojunction at equilibrium before contact (Fig. 1g) and after contact (Fig.…”

Black phosphorus electronics

“…Furthermore, high-k dielectrics have also been employed to passivate the upper surface of BP to reduce scattering [36,91,93,94]. Near ideal SS values were successfully achieved at room temperature by improving the BP/HfO 2 interface quality with thermal treatments [94,95]. Particularly, a record drain current exceeding 1 A/mm has been achieved by integrating 3 nm of HfO 2 and 20 nm of ZrO 2 [93].…”

Recent Advances in Black Phosphorus‐Based Electronic Devices

“…[33][34][35][36] Notably, a hole mobility of ≈536 cm 2 V −1 s −1 and a near ideal SS of ≈66 mV.dec −1 are achieved simultaneously with an ultrathin 3.4 nm HfO 2 gate dielectric. High-performance BP transistors with a thin HfO 2 back gate dielectric have been successfully demonstrated.…”