EFFECT OF MISFIT STRAIN ON PHYSICAL-PROPERTIES OF INGAP GROWN BY METALORGANIC MOLECULAR-BEAM EPITAXY

The effects of misfit strain on physical properties (lattice parameters, photoluminescence, and electron mobility) are discussed for In 1-xGaxP epilayers with a constant thickness of around 0.75 μm grown by metalorganic molecular-beam epitaxy on GaAs(001) substrates. The elastic accommodation of misfit strain is observed in the analysis of lattice parameters and energy-band-gap shift. Tensile strain is relaxed more easily than the compressive strain. Theoretical predictions of critical thickness for elastic-strain accommodation and of energy-band-gap shift agree well with experimental results. The energy-band-gap shift and electron mobility are relatively insensitive to dislocations generated by relaxation of the misfit strain.