Structural and morphological analysis of rf sputtered nano ZnSe coatings as a function of thickness: investigation of the effect of metal contact on MIS structure with ZnSe interfacial layer

In this study, to examine the effect of the thickness difference on the physical properties, ZnSe thin films with three different thicknesses were deposited by the RF sputter technique on Si substrates. Measurements were carried out in XRD and AFM systems to determine the effect of films thickness deposited at 100, 300, and 600 nm on physical properties. It was observed that the crystallinity increased, and the surface roughness decreased with the increase in thickness. 600 nm thick ZnSe thin film was chosen for both XPS analysis and fabrication of Schottky diodes due to its high crystallinity and large grain size. XPS analysis was performed for the determination of the binding energy and elemental analysis on ZnSe. In addition, the effect of different metal contacts on the performance of MIS structures formed with a 600 nm thick ZnSe thin film interfacial layer produced using Au, Ag and Al metals was investigated in detail. Therefore, I–V measurements were performed to examine the electrical properties with Au/ZnSe/Si, Ag/ZnSe/Si ve Al/ZnSe/Si MIS structures. The Schottky diodes’ performances were compared with each other by Thermionic Emission Theory, Cheung I–II, and Norde functions methods. Results show that Au/ZnSe/Si MIS structure performed better than the others.