SearcharxivSearch

arXiv subjects

K. Santhakumar

Publications and source records attributed to K. Santhakumar.

2 recordsLinked to original sources

Optical characterization of GaN by N+ implantation into GaAs at elevated temperature

Both hexagonal wurtzite and cubic zinc blend GaN phases were synthesized in GaAs by 50 keV N+ implantation at 400 deg C and subsequent annealing at 900 deg C for 15 min in N2 ambient. Crystallographic structural and Raman scattering studies revealed that GaN phases were grown for fluence above 2x1017 cm-2. Temperature-dependent photoluminescence study showed sharp direct band-to-band transition peak ~3.32 eV at temperature <= 200K. The intermediate bandgap value, with respect to ~3.4 eV for hexagonal and ~3.27 eV for cubic phases of GaN is an indicative for the formation of mixed hexagonal and cubic phases.

cond-mat.mtrl-sci

Nitrogen ion beam synthesis of InN in InP (100) at elevated temperature

InN phase is grown in crystalline InP(100) substrates by 50 keV N+ implantation at an elevated temperature of 400 deg C followed by annealing at 525 deg C in N2 ambient. Crystallographic structural and Raman scattering studies are performed for the characterization of grown phases. Temperature- and power-dependent photoluminescence studies show direct band-to-band transition peak ~1.06 eV at temperatures <=150K. Implantations at an elevated temperature with a low ion beam current and subsequent low temperature annealing step are found responsible for the growth of high-quality InN phase.

cond-mat.mtrl-sci