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This work analyses the Bi incorporation in InAs1-xBix/InAs(100) epilayers grown by MBE through advanced transmission electron microscopy techniques. Samples grown from 350-400 °C resulted in Bi contents <3.3% exhibiting compositional variation in the growth direction. In contrast, roughly spherical clusters appeared in the sample grown at lower temperatures. The clusters are made up of the binary InBi with a tetragonal PbO phase surrounded by a matrix of InAs0.95Bi0.05indicating the Bi solubility limit in InAs. These InBi crystals underwent a cubic distortion and are tilted 55° with regard to the InAsBi matrix. The crystallographic relationships are analysed in detail.

The distribution of bismuth in InAs1-xBix/GaAs quantum dots is analyzed by atomic-column resolution electron microscopy and imaging simulation techniques. A random Bi distribution is measured in the case of <0.03 ML/s Bi flux during the InAs growth with no significant variations in the shape or size of quantum dots, resulting in a low redshift and the degradation of the photoluminescence. However, for a 0.06 ML/s Bi flux the lateral indium segregation into the quantum dots is enhanced and Bi is incorporated inside them. As a result, a strong redshift and an increase of the peak intensity are found in this sample.