Effect of post-deposition annealing on low temperature metalorganic chemical vapor deposited gallium oxide related materials

Low temperature metalorganic chemical vapor deposition using trimethylgallium and water was investigated. The surface morphology of the film was almost flat at a deposition temperature below 182 degrees C. This flat film was a mixture of nanocrystalline and amorphous phase. The film deposited at a temperature of 272 degrees C resulted in a nanowire structure. X-ray diffraction measurements revealed that the nanowire film was a mixture of gallium hydroxide, gallium oxyhydroxide, and gallium tohdite or gallium oxide. We also found that post-deposition annealing above 600 degrees C significantly changed the crystal structure of the both flat and nanowire films. Monoclinic gallium oxide phase was dominant after the post-deposition annealing above 600 degrees C.