Properties of InGaN Films Grown by Reactive Sputtering

InGaN films were grown on (0001) sapphire substrates by reactive sputtering in nitrogen plasma, using a GaAs wafer and a pure indium target It was found that In, Ga, As, and N atoms adsorb on the substrate and react with each other to form an InGaNAs film at a low substrate temperature With increasing the substrate temperature to 550 degrees C, the arsenic atoms in the grown layer are completely desorbed, forming the InGaN film X-ray diffraction analysis showed that the lattice constant for the c-axis obtained from the (0002) diffraction peak of the InGaN films decreases linearly with an increase in Ga composition, obeying Vegard's law Optical analysis revealed that the InGaN films have a direct band gap structure as InN and GaN and the band gap energy of the InGaN films can be tailored by varying the area ratio of the GaAs wafer to the indium target (C) 2010 The Japan Society of Applied Physics