The photovoltaic and photodiode properties Of Au/Carmine/N-Si/Ag diode

In this study, carmine thin films were deposited on glass slides and n-Si substrates using a spin coater. The deposited carmine film on glass was analyzed using SEM and absorbance measurements. Both in the dark and under daylight, the current-voltage (I-V) characteristics of the reference Au/n-Si/Ag diode and 24 Au/Carmine/n-Si/Ag dots (upper contact points) were measured at room temperature. All diodes exhibited rectifying behavior. The ideality factor (n), barrier height (Φ_b), rectification ratio (RR), and series resistance (Rs) of each dot were determined using the thermionic emission (TE) theory and modified Norde's functions. The n and Φ_b values of the 24 dots were found in the range of 1.52-2.72 and 0.76-0.85 eV in the dark, respectively. Furthermore, a high current rectification ratio of 104 was achieved for the 11 dots in the dark. The photovoltaic and photodiode properties of one (D18 coded) of the Au/Carmine/n-Si/Ag dots under the different light intensities varied from 30 to 100 mW/cm2 at room temperature, and its capacitance-voltage (C–V) characteristics were investigated only in the dark. D18 exhibited typical photodiode behavior with a fill factor (FF) value of 36.2% and an experimental efficiency (ŋ) of 2.45% under 30 mW/cm2 light intensity. It also has a high on/off current (Ion/Ioff) ratio of 7.45x103. The Au/Carmine/n-Si/Ag photodiode demonstrated good stability for 12 on/off cycles without significant changes in its maximum current value. Based on these experimental findings, the high-performance Au/Carmine/n-Si/Ag diode exhibits excellent photodiode behavior, suggesting the potential of carmine thin films for future optoelectronic devices.