Investigation of the Energy Band at the Molybdenum Disulfide and ZrO2 Heterojunctions

The energy band alignment at the multilayer-MoS2/ZrO2 interface and the effects of CHF3 plasma treatment on the band offset were explored using x-ray photoelectron spectroscopy. The valence band offset (VBO) and conduction band offset (CBO) for the MoS2 /ZrO2 sample is about 1.87 eV and 2.49 eV, respectively. While the VBO was enlarged by about 0.75 eV for the sample with CHF3 plasma treatment, which is attributed to the up-shift of Zr 3d core level. The calculation results demonstrated that F atoms have strong interactions with Zr atoms, and the valence band energy shift for the d-orbital of Zr atoms is about 0.76 eV, in consistent with the experimental result. This interesting finding encourages the application of ZrO2 as gate materials in MoS2-based electronic devices and provides a promising way to adjust the band alignment.