Gate-driven band modulation hyperdoping for high-performance p-type 2D semiconductor transistors
Bei Zhao, Zucheng Zhang, Junqing Xu, Dingli Guo, Tiancheng Gu, Guiming He, Ping Lü, Kun He, Jia Li, Zhao Chen, Quan Ren, Lin Miao, Junpeng Lü, Zhenhua Ni, Xiangfeng Duan, Xidong Duan, Xidong Duan, Xidong Duan
Abstract
Tailoring carrier density in atomically thin two-dimensional (2D) semiconductors is challenging because of the inherently limited physical space for incorporating charge dopants. Here, we report that interlayer charge-transfer doping in type III van der Waals heterostructures can be greatly modulated by an external gate to realize a hyperdoping effect. Systematic gated-Hall measurements revealed that the modulated carrier density is about five times that of the gate capacitive charge, achieving an ultrahigh 2D hole density of 1.49 × 10 14 per square centimeter, far exceeding the maximum possible electrostatic doping limit imposed by typical dielectric breakdown. The highly efficient hole-doping enables high-performance p-type 2D transistors with an ultralow contact resistance of ~0.041 kilohm micrometers and a record-high ON-state current density of ~2.30 milliamperes per micrometer.