Competing nucleation of islands and nanopits in zinc-blend Ill-nitride quaternary material system

[摘要] The growth mechanism of quantum dots (QDs), nanopits and collaborative QDs- nanopits structures in GaN-InN-AlN material system is theoretically investigated using the continuum elasticity model. The islands energy versus their volume, as well as the critical energy and volume versus the island and wetting layer lattice constants relative mismatch ratio (strain s), are calculated. It is shown that when the zinc-blend GaN is used as a substrate and when the strain between the wetting layer and a substrate overcomes critical ∗ = 0.039 value, instead of QDs nucleation, the formation of nanopits becomes energetically preferable. Revealed feature is critical and has to be taking into account at QDs engineering in GaInAlN material system.

[发布机构] Department of Physics of Semiconductors and Microelectronics, Yerevan State University, 1 Alex Manoukyan, Yerevan; 025, Armenia^1

[关键词] Continuum elasticity;Critical energy;Growth mechanisms;Material systems;Mis-match ratio;Nanopits;Quaternary materials;Wetting layer