Epitaxial Growth of Two-Dimensional MoO<sub>2</sub>–MoSe<sub>2</sub> Metal–Semiconductor Heterostructures for Schottky Diodes
Ting Kang, Jiawen You, Jun Wang, Yuyin Li, Yunxia Hu, Tsz Wing Tang, Xiaohui Lin, Yunxin Li, Liting Liu, Zhaoli Gao, Yuan Liu, Zhengtang Luo
Abstract
The metal–semiconductor interface fabricated by conventional methods often suffers from contamination, degrading transport performance. Herein, we propose a one-pot chemical vapor deposition (CVD) process to create a two-dimensional (2D) MoO 2 –MoSe 2 heterostructure by growing MoO 2 seeds under a hydrogen environment, followed by depositing MoSe 2 on the surface and periphery. The ultraclean interface is verified by cross-sectional scanning transmission electron microscopy and photoluminescence. Along with the high work function of semimetallic MoO 2 ( E f = −5.6 eV), a high-rectification Schottky diode is fabricated based on this heterostructure. Furthermore, the Schottky diode exhibits an excellent photovoltaic effect with a high open-circuit voltage of 0.26 eV and ultrafast photoresponse, owing to the naturally formed metal–semiconductor contact with suppressed pinning effect. Our method paves the way for the fabrication of an ultraclean 2D metal–semiconductor interface, without defects or contamination, offering promising prospects for future nanoelectronics.