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

Department of Electrical and Computer Engineering, Cornell University, Итак, New York, United States
Applied Physics Letters (Impact Factor: 3.3). 11/2005; 87(16):161905 - 161905-3. DOI: 10.1063/1.2108118
Source: IEEE Xplore


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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    • "Currently, the growth of high-quality In Ga N films has been made possible with the aid of molecular beam epitaxy, even with films comprising a high Indium index [25]. While studying these alloy samples with such a high Indium content, a relatively serious difference is observed between the emission and absorption spectral peaks, referred to as the Stokes' shift. "
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