Thermal annealing of molecular beam epitaxy-grown InGaN/GaN single quantum well

Nils Kaufmann (1) , Amélie Dussaigne (1) , Denis Martin (1) , Pierre Valvin (2) , Thierry Guillet (2) , Bernard Gil (2) , Francesco Ivaldi (3) , Slawomir Kret (3) , N. Grandjean (1)

1 Institute of Condensed Matter Physics [Lausanne]
2 L2C - Laboratoire Charles Coulomb
3 IFPAN - Institute of Physics [Warsaw]

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.

Domaines: Autre [cond-mat.other]

Nils Kaufmann, Amélie Dussaigne, Denis Martin, Pierre Valvin, Thierry Guillet, et al.. Thermal annealing of molecular beam epitaxy-grown InGaN/GaN single quantum well. Semiconductor Science and Technology, 2012, 27 (10), pp.105023. ⟨10.1088/0268-1242/27/10/105023⟩. ⟨hal-00805853⟩