Indium gallium nitride (InGaN)-optical properties and technological implications

Abstract The successful introduction of indium into gallium nitride using epitaxial growth techniques has lead to the recent introduction of the InGaN-based blue laser diode and of light-emitting diodes that span the visible spectrum. However, it is believed that indium nitride is insoluble in gallium nitride at the growth temperatures used in fabricating such devices, with the result that a vigorous debate has started on the state of aggregation of the light-emitting material on the nanoscale. While most research has focused upon materials with modest indium nitride fractions, it is at high and low concentrations that we observe the most interesting and puzzling optical effects.