Dense uniform arrays of site-controlled quantum dots grown in inverted pyramids

The growth and optical characteristics of dense, pyramidal single semiconductor quantum dot (QD) heterostructures with pitch between 500-300 nm were studied. It was found that the dense arrays were grown by organometallic chemical vapor deposition on (111)B QD substrates containing dense inverted pyramid recess patterns which were prepared by electron beam lithography and wet chemical etching. Low-temperature cathodoluminescence showed the high uniformity of dense QD arrays accross micrometer-scale areas. It was observed that the low-temperature microphotoluminescence spectra of the dense arrays showed distinct luminescence from the QDs linewidth of 1-3 MeV.