Compositional variation and ordering of GaxIn1−xP on GaAs structured substrates

Nominally lattice‐matched GaxIn1−xP grown on near‐(001) GaAs substrates containing etched trenches oriented in the [110] and [110] directions have been analyzed by scanning electron microscopy, energy dispersive x‐ray spectrometry, transmission electron microscopy, and cathodoluminescence. The trench walls exhibit a high deposition rate and Ga content, accentuated on walls that are oriented toward {111}A planes. Walls oriented toward {111}B lead to selective atomic ordering on (111) or (111) planes, whereas walls oriented toward {111}A exhibit disorder. We discuss the combined effect of composition and ordering on the band gap.