Growth and humidity-dependent electrical properties of bulk-like MoS2 thin films on Si

摘要: Bulk-like molybdenum disulfide (MoS2) thin films were deposited on Si substrates using a dc magnetron sputtering technique and n-MoS2/p-Si junctions fabricated at room temperature (RT) 400 °C, respectively. The typical oscillating modes of E12g A1g shown in the Raman spectra as-grown MoS2 films. Atomic force microscopy illustrated that surfaces composed dense nanoscale grains scanning electron revealed existence large quantities pores surface. current–voltage curves showed obvious rectifying characteristics due to energy-band bending near interface MoS2/Si. exhibited humidity-dependent electrical properties. Compared with one film RT, junction °C much more sensing properties humid gas. In particular, sensitivity device could be tuned by external fields. forward voltage range, currents increased significantly after was exposed conditions. response increasing reached saturated value V = 1.9 V. performance featured high sensitivity, fast recovery. current reverse range decreased under condition. This contrary range. We also studied dependence humidity levels. An almost linear correlation obtained measured mechanisms MoS2/Si heterojunction proposed.