Optical, electronical and structural study of Scandium Sluminum Nitride alloy for optoelectronic applications

Abstract

This manuscript presents a study on sputtered ScxAl1-xN layers for use in ultraviolet optoelectronics applications such as light-emitting diodes(LEDs)and ultraviolet laser diodes(UV-LDs).By adding a certain amount of scandium into the hexagonal structure of AlN deposed on silicon Si (111) substrate, changes in the compound can be observed.In this work,X-ray photoemission Spectroscopy(XPS) is used to determine the concentration of Scandium in the samples. The lattice parameter c of hexagonal ScxAl1-xN is determined by X-ray diffraction (DRX). Optical characterizations such as UV-VIS spectroscopy and spectroscopic ellipsometry(SE)are used to determine the binding energy and absorption coefficient of scandium aluminum nitride.Scanning Electron Microscopy(SEM)is used to determine the roughness of the samples and to analyze the morphology of the ScAlN . Energy Dispersive X-ray (EDS) is used to characterize a sample’s chemical characteristics or determine its element composition.Additionally,infrared spectroscopy is performed to obtain a detailed overview of the vibrational bands in ScxAl1-xN,as a function of x. ScAlN is a composite material of great interest,particularly in lectromechanical and optoelectronic applications where its optical properties influence most electrical and mechanical properties.To model these properties,several theories such as the finite element method,the Rayleigh-Rice theory,and the effective medium approximation(EMA)were tested.This work focuses on simulating ScAlN parameters to improve the properties of a light-emitting diode.For this purpose,the GPVDM software is used to simulate the studied materials in an LED system. Considerable efforts were made to adapt the requirements to the software to achieve the best possible result with the data from the material used.The results obtained were satisfactory and in agreement with the literature.