Electronic Property of PdSe2 Thin Films Fabricated by Post-selenization of Pd Films

At present, the approaches to fabricate PdSe2 thin films mainly focus on mechanical exfoliation and chemical vapor deposition. In this study, we report a simple and efficient method to fabricate PdSe2 thin films on SiO2/Si substrates. Firstly, a Pd metal layer was deposited on a SiO2/Si substrate using magnetron sputtering. Then the PdSe2 thin film was obtained through selenization of the Pd layer at certain temperatures in a vacuum quartz ampule containing Se powder. According to the cross-sectional high-resolution transmission electron microscopy (HRTEM) image, the as-grown PdSe2 thin film has an average thickness of about 30 nm. The correlation between selenization temperature and electronic transport properties of PdSe2 thin films was investigated. PdSe2 thin films with a hole carrier concentration of similar to 10(18) cm(-3) and a mobility of similar to 48.5 cm(2) .V-1 .s(-1) are realized at a low selenization temperature of 300 V. It is worth noting that the mobility obtained by the vacuum selenization is superior to that of the p-type PdSe2 thin films fabricated by mechanical exfoliation from bulk PdSe2 single crystals. In addition, a relatively large room-temperature magnetoresistance (MR) of 12% is achieved for the PdSe2 thin films selenized at 300 V. With the increase in the selenization temperature from 300 V, mobility and magnetoresistance decrease due to the evaporation of Se element at high temperatures. This work demonstrates that present one-step selenization process is a facile and efficient approach to synthesize PdSe2 films, which could actually be used to prepare PdSe2 films in a large scale and may have potential applications for next-generation electronic and magneto-electronic devices.

Automated summary

A simple and efficient method to fabricate PdSe2 thin films on SiO2/Si substrates is reported in this study. The approach could potentially be used for large-scale preparation of PdSe2 films and have potential applications in next-generation electronic and magneto-electronic devices.