Fabrication of GaN/p-Si diodes by light-assisted electrodeposition and measurement of switching times

In this thesis, a GaN/p-Si diode structure was fabricated by coating GaN on p-Si (100) substrates using light-assisted electrodeposition and dark environment electrodeposition. The electrolyte solution was prepared using a mixture of Gallium Nitrate, Ammonium Nitrate and deionized water. In all electrodeposition processes, Platinum plate was used as anode and p-Si was used as cathode, the electrodeposition time was 6 hours and the current was kept constant at 5 mA. In order to investigate the variation of ambient parameters during the electrodeposition process, a system was installed to measure and record time dependent parameters such as current applied to the electrodes, ambient temperature, electrolyte temperature, humidity and pH. XRD and SEM analysis of the GaN/p-Si diode structure produced by light-assisted electrodeposition method revealed that the material coated on p-Si is GaN with (002) orientation consisting of spherical particles. Current-Voltage (I-V) measurements carried out in the range of 293-373 K in 10 K steps in a temperature-dependent manner showed that the structure has diode characteristics and two-dimensional interfacial state density distribution analysis was performed using these measurements. Finally, the temperature-dependent switching time was measured and analyzed, and the switching time of the GaN/p-Si diode structure at room temperature was measured as 400 ns. Keywords: Electrodeposition, switching time, diode, GaN, electrical characterization, light-assisted electrodeposition