Structural and optical characteristics of 1.65 m-emitting quantum dots on InP substrate grown by selected area-MOVPE

Diblock co-polymer lithography and selected area metalorganic vapor phase epitaxy was used to fabricate quantum dots (QDs) on InP substrates for application in C-band communication. Initial structural and optical studies were carried out on three layered quantum dots with compressively strained In0.76Ga0.24As well and lattice-matched either In0.53Ga0.47As or In0.52Al0.48As as barriers. Photoluminescence studies at room tempera-ture and at low temperature indicated weak carrier confinement in the QDs with In0.53Ga0.47As barrier, which leads to its broader PL linewidth, compared to QDs with In0.52Al0.48As barrier. This makes InAlAs a better choice for the barrier material in device applications. However, the higher growth rate of InAlAs inside the selected area and shape of the dots resulting from in-situ etching are some issues that need to be addressed to optimize the optical properties of QDs.