Investigation of Trap States, Series Resistance and Diode Parameters in Al/Gelatin/n-Si Schottky Diode by Voltage and Frequency Dependent Capacitance and Conductance Analysis

Inorganic-organic Schottky contacts based on Gelatin on n-Si wafer have been prepared by a spin coating technique. The reverseand forward bias capacitance-voltage (C-V) and conductance-voltage (G-V) properties of the Al/Gelatin/n-Si Schottky diode atroom temperature in the frequency range from 30 kHz to 1 MHz have been computed by taking into account the series resistance(Rs) and interface states (Dit) effects. The conductance and Hill-Coleman method were used to determine interfacial layercapacitance (Cin), Rs and Dit. The values of Rs and Dit were determined as 810 and 1.52 x-1012 eV-1 cm-2 for 30 kHz and 38 and 3.38 x 1011 eV-1 cm-2 for 1 MHz. Experimental results corroborated that the Rs and Dit are influential parameters whichseverely impact the basic electrical parameters of Al/Gelatin/n-Si Schottky diode. Both the measured capacitance (Cm) andconductance (Gm) were corrected in order to obtain the real diode capacitance (Cc) and conductance (Gc). Schottky diodeparameters such as barrier height (φB), ionized donor density (ND), Fermi level (EF), built-in voltage (VD) were extracted from thefrequency-dependent Cc-V and 1 Cc V2 /-relations. The values of φB was determined as 0.796 eV for 30 kHz and 1.090 eV for1 MHz. The Rs and Dit values were observed to decrease, while the φB values increase as the frequency increases. Results revealthat the fabricated diode can potentially be used as a promising candidate material for electronics applications.