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Effect of Native Defects on Optical Properties of InxGa1-xN Alloys

S. X. Li·E. E. Haller·K. M. Yu·W. Walukiewicz·J. W. Ager III·J. Wu·W. Shan·Hai Lu·William J. Schaff
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Abstract

The energy position of the optical absorption edge and the free carrier populations in InxGa1-xN ternary alloys can be controlled using high energy 4He+ irradiation. The blue shift of the absorption edge after irradiation in In-rich material (x > 0.34) is attributed to the band-filling effect (Burstein-Moss shift) due to the native donors introduced by the irradiation. In Ga-rich material, optical absorption measurements show that the irradiation-introduced native defects are inside the bandgap, where they are incorporated as acceptors. The observed irradiation-produced changes in the optical absorption edge and the carrier populations in InxGa1-xN are in excellent agreement with the predictions of the amphoteric defect model.

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S. X. Li, E. E. Haller, K. M. Yu, W. Walukiewicz, J. W. Ager III, J. Wu, W. Shan, Hai Lu, William J. Schaff. 2005-08-05. Effect of Native Defects on Optical Properties of InxGa1-xN Alloys. https://doi.org/10.1063/1.2108118

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