The growth and characterization of Sn doped Al/ZnS/p-Si structures

In this study, undoped and Sn (tin) doped ZnS (zinc sulfide) solutions were coated on glass and p-type Si (silicon) crystal using the sol-gel method. The Sn contribution amount changed between 0%-10%. The films are coated 15 layers on glass and 6 layers on crystal. Optical parameters such as thickness d, forbidden band gap Eg and refractive index n of the materials were investigated by using UV-vis-NIR measurements of thin films coated on glass. The crystal structure of the materials was determined with help of XRD spectrum. According to the results obtained, it was observed that the films grown on both glass and crystal crystallize as a cubic structure. Current-voltage I-V measurements of doped and undoped ZnS/p-Si structures were taken at room temperature in the dark, and diode properties of the samples were investigated with the help of these measurements. Diode parameters such as ideality factor n, barrier height ϕb and series resistance Rs were calculated using Thermionic emission (TE), Norde, Lien and Cheung-Cheung methods. In addition, capacitance-voltage C-V measurements of doped and undoped ZnS/p-Si in the frequency range of 10kHz-1.5MHz were taken and diode parameters were determined in detail by using these measurements. In addition, illuminated I-V measurements of doped and undoped ZnS/p-Si structures were determined under 100mW/cm2 illumination power in order to investigate photodiode characteristics of the samples.