Ref HAL: hal-00805853_v1
DOI: 10.1088/0268-1242/27/10/105023
WoS: 000309111800025
Exporter : BibTex | endNote
16 Citations
Résumé:

The effect of thermal annealing on In0.25Ga0.75N/GaN quantum wells grown by molecular beam epitaxy at 550°C is investigated. A strong increase in the 300 K photoluminescence (PL) intensity is observed for samples annealed at 880°C, while degradation occurs for higher temperatures. The improvement of the optical properties is ascribed to higher internal quantum efficiency (IQE), as indicated by temperature-dependent and time-resolved PL experiments. The effect of carrier localization due to possible quantum dot formation via indium clustering is ruled out based on high-resolution transmission electron microscopy imaging. IQE improvement is thus attributed to a reduction of point defects upon annealing.