Disordering of the ordered structure in metalorganic chemical vapor deposition grown Ga_0.5In_0.5P on (001) GaAs substrates by zinc diffusion Available to Purchase

Transmission electron microscopy is used to study sublattice atomic ordering in as‐grown and Zn‐diffused epitaxial layers of Ga_0.5In_0.5P that are grown lattice matched to GaAs by low‐pressure metalorganic chemical vapor deposition. The as‐grown Ga_0.5In_0.5P layers exhibit an ordered trigonal structure with In‐Ga ordering occurring on only two sets of {111} planes. After a Zn diffusion is performed at 650 °C, the ordered structure is no longer observed in selected area diffraction patterns. Simultaneously, the room‐temperature photoluminescence peak shifts by ≊90 meV to higher energy, as compared to the undiffused samples. These data provide direct experimental evidence that Ga_0.5In_0.5P with an ordered distribution of Ga and In atoms on the column III sublattice can be converted to a random alloy by Zn diffusion.