Comparison of optical, electrical, and surface characteristics of InGaN thin films at non-flow and small nitrogen flow cases

Abstract

InGaN films in the non-flow and a small flow of nitrogen cases were fabricated by the RFMS (Radio Frequency Magnetron Sputter) method to compare crucial physical characteristics of its material. From the XRD analysis, application of small nitrogen flow in the InGaN thin film growth has been observed to result in changes in the crystal size, texture coefficient, and crystal structure parameters of the film. AFM results showed both films obtained have tightly packed granular, and almost homogeneous, and Nano-structural properties, but they are different in roughness, as increased by applying small nitrogen flow. Optical conductance peaks of the material in non-flow and small flow case were 1.3957 × 10 10and 1.1496 × 10 10(S / m ) , showed a decrement in optical conductance by small nitrogen flow. In the same manner, electrical conductance peaks of the material in non-flow and small flow case were 5.2512 × 10 12and 5.2236 × 10 12(S ) , showed a decrement in electrical conductance by small nitrogen flow. In addition, the electrical conductivity of the InGaN material has been obtained at higher than the optical conductivity value of the InGaN material in both cases. Also, it was noticed that direct allowed optical band gap energy non-flow and small flow cases were 2.65 and 2.69 eV, displayed increased by applied small nitrogen flow. Essentially, many noteworthy physical properties such as crystalline size, texture coefficient, optical/electrical conductivity, the surface roughness of the films have been compared and studied for the non-flow and a small flow of nitrogen cases. Therefore; a better understanding of the structural/crystal and electrical characteristics of the InGaN film by applying/optimizing different growth conditions will be able to pave the way for InGaN device studies. © 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.