QUANTITATIVE OXYGEN MEASUREMENTS IN OMVPE ALXGA1-XAS GROWN BY METHYL PRECURSORS

Oxygen has always been considered to be a major contaminant in the organo-metallic vapor phase epitaxy (OMVPE) of AlxGa1-xAs. Oxygen incorporation has been invoked as a contributor to low luminescence efficiency, dopant compensation and degradation of surface morphology among other deleterious effects. This study presents quantitative measurements of oxygen concentration in nominally high purity AlxGa1-xAs. The oxygen concentration was measured as a function of alloy composition, growth temperature, and V/III ratio. Quantitative secondary ion mass spectroscopy (SIMS) measurements were used to determine the oxygen content as well as the carbon concentration in the film. The oxygen concentration increases with decreased growth temperature and V/III ratio while increasing superlinearly with Al content in the epitaxial layer.