Modulating p-type doping of two dimensional material palladium diselenide

The van der Waals heterostructures have evolved as novel materials for complementing the Si-based semiconductor technologies. Group-10 noble metal dichalcogenides (e.g., PtS 2 , PtSe 2 , PdS 2 , and PdSe 2 ) have been listed into two-dimensional (2D) materials toolkit to assemble van der Waals heterostructures. Among them, PdSe 2 demonstrates advantages of high stability in air, high mobility, and wide tunable bandgap. However, the regulation of p-type doping of PdSe 2 remains unsolved problem prior to fabricating p–n junction as a fundamental platform of semiconductor physics. Besides, a quantitative method for the controllable doping of PdSe 2 is yet to be reported. In this study, the doping level of PdSe 2 was correlated with the concentration of Lewis acids, for example, SnCl 4 , used for soaking. Considering the transfer characteristics, the threshold voltage (the gate voltage corresponding to the minimum drain current) increased after SnCl 4 soaking treatment. PdSe 2 transistors were soaked in SnCl 4 solutions with five different concentrations. The threshold voltages from the as-obtained transfer curves were extracted for linear fitting to the threshold voltage versus doping concentration correlation equation. This study provides in-depth insights into the controllable p-type doping of PdSe 2 . It may also push forward the research of the regulation of conductivity behaviors of 2D materials.