Novel InGaAs/GaAs Quantum Dot Structures Formed in Tetrahedral-Shaped Recesses on (111)B GaAs Substrate Using Metalorganic Vapor Phase Epitaxy

Abstract
We report a novel GaAs/InGaAs/GaAs quantum dot structure formed in a tetrahedral-shaped recess (TSR) pattered on a (111)B GaAs substrate with anisotropic chemical etching. The pseudomorphic heterostructure shows two clear photoluminescence (PL) peaks, which are attributed to an In anisotropic incorporation on (111)B compared to (111)A. Cathodoluminescence at a lower energy peak with InGaAs of 2.5 nm shows bright image at the bottom of TSRs, which indicates the local minimum of potential energy is at the bottom of the TSR.