Site-controlled InGaAs/GaAs pyramidal quantum dots grown by MOVPE on patterned substrates using triethylgallium

•Site-controlled QDs were grown with triethylgallium as a precursor.•The QDs ensembles exhibited narrow linewidths and better spectral homogeneity across the sample.•Narrow linewidth could be obtained reproducibly and tuned from 870 nm to 960 nm.

The fabrication and characterization of site-controlled InGaAs/GaAs quantum dots (QDs) made by MOVPE using triethylgallium (TEGa) on patterned {1 1 1}B GaAs substrates are reported. Results are compared to more traditional pyramidal QD structures grown employing trimethylgallium (TMGa). Several potential advantages of the use of TEGa are demonstrated, including more reproducible achievement of QD transitions with narrow (<100 µeV) linewidths and better spectral uniformity across patterned substrates. These features are important for QD integration in optical cavities, which require both site and spectral stringent control.