Investigation of GaN/InGaN thin film growth on ITO substrate by thermionic vacuum arc (TVA)

Abstract

Group-III nitride semiconductors covering infrared, visible and ultraviolet spectral range have direct bandgaps changing from 0.7 eV (InN) to 3.4 eV (GaN). With this feature, optoelectronic devices such as light emitting diodes, laser diodes and ultraviolet (visible rays-UV) photodetectors are made. It is possible to grow high-quality InGaN epitaxial layers by modern crystal growth techniques such as molecular beam epitaxy, radio frequency sputtering method and metal organic chemical vapor deposition. Compared with these methods, the Thermionic Vacuum Arc, which is promising thin film growth technique, is relatively inexpensive and quite effective approach for preparing InGaN thin films. The purpose of this research is to investigate the physical properties of the film. The XRD patterns of the InGaN thin films deposited on the ITO substrate exhibited polycrystal structure. The larger crystallite size and smaller FWHM indicate better crystallization. Microstrain values also exhibit good crystallite films respect to the low dislocation density. This film has a potential for photovoltaic devices based on the absorbance graph. It was observed that the compound is homogeneously dispersed on the surface and that there is a nanoporous structure.

Effect of annealing temperature on structural morphological and optical properties of spray pyrolized Al-doped ZnO thin films

“…The dislocation density and strain values of the film have been found to decrease with the increase of annealing temperature up to 450°C and then increases. This tendency indicates that annealing reduces the lattice defects of the films and increases the crystalline quality by modifying the periodic arrangements of atoms in the crystal lattice [1,2,18,19]. The dislocation density and strain value show a reverse relation when the films are annealed above 450°C i.e.…”

“…Dislocations are linear defects in the crystal structure. Dislocation density (δ) is defined as the dislocation line length in the unit volume and is a measure of the number of defects in the crystal [18]. The dislocation density of the deposited and annealed films can be calculated by the following equation…”

SnO2 Nanoparticles: Green Synthesis, Characterization, and Water Treatment

“…The micro-strain is calculated from XRD data using the equation: 39 In the crystal structure, dislocations are linear defects. The dislocation density δ is a measure of defects number in the crystal 37,40 which is defined as dislocation line length per unit volume the following equation is used to estimate the dislocation density of SnO 2 NPs at different reactions temperatures and different extract concentrations.…”

Thermionic Vacuum Arc—A Versatile Technology for Thin Film Deposition and Its Applications

“…An alternative study in depositing the AlGaAs films by TVA presents [168]. The InGaN thin film deposited by TVA on GaN and ITO substrate was studied in [169]. In this way, a sandwich layer ITO/GaN/InGaN was created with an average thickness 250 nm.…”