Surface segregation effects of In in GaAs

Abstract

Photoluminescence (PL), secondary-ion mass spectroscopy (SIMS), and cross-sectional transmission electron microscopy (TEM) measurements have been performed to assess surface segregation of In in GaAs during molecular-beam epitaxial growth of InAs monolayers between GaAs layers. The InAs growth temperature at which In segregation is detectable depends on the characterization technique used; using PL it is above 420 °C, but from TEM and SIMS it is 420 and 340 °C, respectively. These results highlight the need for complementary information to provide a better understanding of the segregation phenomenon. SIMS data show that the total amount of In segregating and the extent of its distribution both increase with InAs deposition temperature.