ON THE ORIGIN OF OVAL DEFECTS IN METALORGANIC MOLECULAR-BEAM EPITAXY OF INP

We have studied the dependence of oval-shaped defects on growth conditions during metalorganic molecular beam epitaxy of InP. The density of oval defects is independent of growth conditions but strongly dependent on the initial substrate surface preparation. Contaminants existing on the surface prior to growth are indicated as the likely cause of oval defect formation due to local enhancement of metalorganic molecules cracking on the surface and the subsequent formation of group III rich structures. High densities of such defects are shown to degrade the optical properties of InGaAs quantum wells.© 1995 American Institute of Physics.