Microstructural origins of localization in InGaN quantum wells

R A Oliver (1) , S E Bennett (1) , T Zhu (1) , D J Beesley (1) , M J Kappers (1) , D W Saxey (2) , A Cerezo (2) , C J Humphreys (1)

1 DMSM - Department of Materials Science and Metallurgy [Cambridge University]
2 Department of Materials

The startling success of GaN-based light emitting diodes despite the high density of dislocations found in typical heteroepitaxial material has been attributed to localisation of carriers at non-uniformities in the quantum wells which form the active region of such devices. Here, we review the different possible structures within the quantum wells which could act as localisation sites, at length scales ranging from the atomic to the tens of nanometre range. In some quantum wells several localisation mechanisms could be operational, but the challenge remains to optimise the quantum wells ' structure to achieve improved quantum efficiencies, particularly at high excitation powers.

Mots clés: GaN; InGaN; quantum wells; localisation; transmission electron microscopy; atom probe tomography; spinodal decomposition PACS codes 68.37.-d; 68.65.Fg; 81.07.St; 78.55.Cr; 81.05.Ea III-V

R A Oliver, S E Bennett, T Zhu, D J Beesley, M J Kappers, et al.. Microstructural origins of localization in InGaN quantum wells. Journal of Physics D: Applied Physics, 2010, 43 (35), pp.354003. ⟨10.1088/0022-3727/43/35/354003⟩. ⟨hal-00569690⟩