Growth mode and strain relaxation of InAs on InP (111)A grown by molecularbeam epitaxy

Growth mode and strain relaxation of molecular-beam-epitaxy grown InAs/InAl As/InP (111)A system have been investigated using reflection high-energy el ectron diffraction, transmission electron microscopy, atomic force microsco py, and photoluminescence measurements. In direct contrast to the well-stud ied InAs/GaAs system, our experimental results show that the InAs grown on InAlAs/InP (111)A follows the Stranski-Krastanov mode. Both self-organized InAs quantum dots and relaxed InAs islands are formed depending on the InAs coverage. Intense luminescence signals from both the InAs quantum dots and wetting layer are observed. The luminescence efficiency of (111)A samples is comparable to that of (001) samples, suggesting the feasibility of fabri cating quantum dot optoelectronic devices on InP (111)A surfaces. (C) 1999 American Institute of Physics. [S0003-6951(99)01010-4].