The effects of sulfur concentration on the growth rate of selective MOCVD grown InP [for BH LD]

Ridge structures with various widths of about 5 μm were selectively grown on open stripe regions between pairs of mask stripes. In narrow regions both lateral gas phase diffusion and substrate migration contribute to the enhanced growth, and affect the surface flatness. In addition, rabbit-ear growth occurs at both edges of selective grown mesa structure and prevents flat burial of the mesa. The results are presented of a study of the effects of sulfur, on the growth rate of InP in selective area growth processes. It was found that the growth rate of the n-type InP layer on the open stripes is a sensitive function of the H₂S flow rate. It was also found that the growth rate on (100) planes (mesa top) differ frpmm that on (111)B (side facet), and can be controlled by the H₂S flow rate. A complete growth suppression can be achieved at partial pressure of 2×10^-3 Torr. Using this novel MOCVD growth technique, a selectively grown buried heterostructure laser diode is successfully fabricated in one step growth