Van der Waals Heterostructures Based on Two-dimensional Materials

Two-dimensional (2D) layered materials offer a platform to build well-designed heterostructures due to their weak van der Waals interactions between each individual layer and dangling-bond-free surface. It is therefore possible to assemble high quality and multifunctional heterostructures using different 2D materials. Herein, a high performance gate tunable P-I-N heterojunction has been demonstrated using BP/WSe₂ /MoS₂ system, where the PN junction is unintentionally formed by p-type BP and n-type MoS₂, and WSe₂ thin film acts as photo carrier generation layer and carrier transportation layer. With well-designed bandgap alignment, such van der Waals heterostructure shows versatile applications integrated in one single device, including high performance optoelectronic photodetector and logic inverter. When under illumination, excellent photoresponse has been demonstrated, covering 10³ large photocurrent-to-dark current ratio and 10⁹ Jones of specific detectivity at zero bias. As a vertical complementary inverter, this device exhibits decent voltage transfer from logic 1 to logic 0. This work indicates the great potential in future functional optoelectronic applications as well as integrated logic circuits.