  InGaN is an ideal alloy system for optoelectronic devices due its tunable
band gap. Yet high-quality InGaN requires high In concentration, which is a
challenging issue that limits its use in green-light LEDs and other devices. In
this paper, we investigated the surfactant effect of Sb on the In incorporation
on InGaN (000-1) surface via first-principles approaches. Surface phase diagram
was also constructed to determine surface structures under different growth
conditions. By analyzing surface stress under different structures, we found
that Sb adatom can induce tensile sites in the cation layer, enhancing the In
incorporation. These fi ndings may provide fundamental understandings and
guidelines for the growth of InGaN with high In concentration.
