MOVPE growth of high quality p-type InGaN with intermediate In compositions

MOVPE growth and Mg doping of InGaN films with intermediate In compositions have been studied. By optimizing the growth temperature and TMI/(TMI+TEG) molar ratio, InGaN with In compositions from 0.05 up to 0.75 are successfully grown without phase separation and metallic In incorporation. The growth temperature of InGaN is discussed from the viewpoints of not only composition control but also crystalline quality of grown InGaN. Mg doping of InGaN with In contents of 0.05-0.4 has been studied using Cp 2 Mg as a Mg precursor. p-type conduction is achieved for InGaN films with In content of 0.25-0.4 when the Cp 2 Mg/(TMI+TEG) molar ratio is 2-5%. Compared with the previous study (Islam et al. (2009) [6]), p-type conduction is achieved with reduced Cp 2 Mg supply. This is due to the improved crystalline quality of the present InGaN films. It is found that p-type conduction is easily obtained for InGaN films grown on GaN/sapphire templates, compared with those grown on GaN buffer/sapphire substrates. This is also due to the better crystalline quality of InGaN films grown on the templates.