Optical and Electrical Characterization of n-MoS2/p-Si Heterojunction Diode

This work reports the optical and electrical characteristics of n- Molybdenum disulfide (MoS2)/p-Si based heterojunction diodes. MoS2 quantum dots (QDs) based thin film synthesized on the p-Si substrate by facile-colloidal synthesis process followed by the spin coating. The optical properties of MoS2 thin film have investigated by excitation dependent photoluminescence (PL) spectra and UV–Vis absorption spectra. Absorption spectra show only one peak in the near-UV region with a wavelength of < 300 nm which is typical exciton characteristics of MoS
2
QDs. The excitation dependent PL spectra show a redshift in peak wavelength with an increase in the excitation wavelength from 360 nm to 480 nm. The electrical characteristics are determined by room temperature current-voltage (I-V) and capacitance-voltage (C-V) characteristics. The value of barrier height (φ
B
) and ideality factor (η) from I-V is calculated as 0.23 eV and 1.95 with a good current rectification ratio of 7480 at ±2 V.