Illumination impact on the electrical characteristics of Au/Sunset Yellow/n-Si/Au hybrid Schottky diode

In this study, semiconductor device applications of organic material sunset yellow (SY) (C₁₆H₁₀N₂Na₂O₇S₂) has been investigated. The SY thin film was grown on n-Si via spin coating method and the Au/SY/n-Si/Au heterojunction was fabricated. The basic diode parameters of device were determined by the current–voltage (I–V) and capacitance–voltage (C–V) measurements at the room temperature. The values of the ideality factory (n) and barrier height (Φ_b) were evaluated as 1.15 and 0.70 eV, respectively; and series resistance (R_s) of device was found using Norde functions. The values of built in potential, donor concentration, Fermi energy level and barrier height were also estimated from the linear C⁻²–V curves with reverse bias room temperature and difference frequency. Furthermore, I–V measurements were applied under different illuminations; some photoelectrical parameters of device were evaluated to understand the photo response properties of the device. Consequently, the results confirmed that the barrier height can be modified by interfacial SY layer, and the device can be used in optoelectronic applications such as optical sensor or photodiode.