Indium reevaporation during molecular beam epitaxial growth of InGaAs layers on GaAs substrates

We have studied the In reevaporation behavior during InGaAs growth by molec ular beam epitaxy (MBE) on GaAs substrates along with lattice-matched InGaA s on InP substrates for comparison. A proposed rate-equation model for surf ace processes has proved that the in surface segregation effects due to the In-Ga replacement on the activation energy of In desorption are negligible , The growth temperature was changed from 540 degrees C to 680 degrees C, T he growth rates R-InGaAs for InGaAs and R-GaAs for GaAs were determined by measuring the intensity oscillation of reflection high-energy electron diff raction (RHEED) beam. The activation energy of In reevaporation decreases w ith the strain in InGaAs/GaAs. The In incorporation fraction decreases with the strain in InGaAs, The In incorporation fractions of unstrained InGaAs/ InP systems are larger than those of strained InGaAs/GaAs systems. The comp ressive stress in InGaAs shows stronger influence on decreasing In incorpor ation as compared to tensile stress.