MOVPE growth of GaNAs using tertiarybutylarsine (TBA) and dimethylhydrazine (DMHy)

GaNAs alloys were successfully grown on GaAs substrates by low-pressure MOVPE with all organometallic sources of triethylgallium (TEG), tertiarybutylarsine (TBA), and dimethylhydrazine (DMHy). We studied the incorporation behavior of nitrogen in terms of growth temperature and molar flow ratio of supplied sources. A ratio of TBA to the group III element, As/III, as low as 1.4 was found to be possible to grow GaNAs with good crystalline quality. Since the nitrogen concentration of more than 3% was easily achieved by our growth technique. The combination of TBA-DMHy as V precursors is a candidate for the growth of other III-V alloys containing nitrogen. We observed a decrease in PL intensity with enhancing nitrogen incorporation into solids: lowering growth temperature and increasing the fractional flow ratio of DMHy. In order to recover from degradation in optical properties, Rapid Thermal Annealing (RTA) was demonstrated and found to be effective. Therefore MOVPE using TBA-DMHy combined with post-annealing is expected to obtain GaNAs alloys with high nitrogen concentration as well as excellent optical properties