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arXiv · 0708.2211

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

S. Dhara·P. Magudapathy·R. Kesavamoorthy·S. Kalavathi·K. G. M. Nair·G. M. Hsu·L. C. Chen·K. H. Chen·K. Santhakumar·T. Soga
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Abstract

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.

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S. Dhara, P. Magudapathy, R. Kesavamoorthy, S. Kalavathi, K. G. M. Nair, G. M. Hsu, L. C. Chen, K. H. Chen, K. Santhakumar, T. Soga. 2007-08-16. Optical characterization of GaN by N+ implantation into GaAs at elevated temperature. https://doi.org/10.1063/1.2099542

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