Sulfur doped indium phosphide on silicon substrate grown by epitaxial lateral overgrowth

The epitaxial lateral overgrowth (ELOG) of sulfur doped InP from ring shaped openings on SiN_x masked InP/Si substrate in low pressure hydride vapor phase epitaxy system was investigated. Octahedral shaped ELOG InP templates with smooth surface were formed and studied by cathodoluminescence (CL). High energy transition at 825 nm (1.52 eV) due to the band filling effect caused by high concentration sulfur atoms trapped in threading dislocations was observed in spectra at 80 K. The band edge transition at 875 nm (1.42 eV) in CL spectra has no red shift caused by thermal strain. As observed in panchromatic image, defect free area was surrounded by high density threading dislocations that were pined by sulfur atoms due to impurity hardening. The quality of the ELOG InP templates is promising for the integration of photonic active layer on Si substrate.