Thermodynamic analyses were carried out to understand the influence of lattice constraint from InN and GaN substrates on the relationship between solid composition x of InxGa1-xN films and input mole ratio RIn (= PIn0/(PIn0 + PGa0), where Pi0 is the input partial pressure of element i) during molecular beam epitaxy. The calculation results suggest that a compositionally unstable region is found at the GaN-rich region for InGaN on InN at higher temperatures while that for InGaN on GaN can be seen at the InN-rich region. This is because the maximum enthalpy of mixing shifts toward x ∼ 0.10 for InGaN on InN and toward x ∼ 0.80 for InGaN on GaN compared with x ∼ 0.50 for stress-free InGaN.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)