Atomic layer epitaxy has been found to be effective in achieving 2-dimensional growth of highly mismatched InP/GaAs heterostructures from the initial stages. The structural characterization of the layers has been carried out by conventional and high resolution transmission electron microscopy and high resolution x-ray diffractometry. 60-degrees type misfit dislocations have been observed at the heterointerface in all the structures investigated. As the layer thickness increases, neighboring 60-degrees dislocations can react to form 90-degrees edge type dislocations. Planar defects extending into the layers along the {111} planes have also been observed. Finally, the elastic strain relaxation has been correlated with the nature and density of the observed crystal defects.
ELECTRON-MICROSCOPY AND X-RAY-DIFFRACTION CHARACTERIZATION OF INP GAAS GROWN BY ATOMIC LAYER EPITAXY
L Lazzarini;G Salviati
1993
Abstract
Atomic layer epitaxy has been found to be effective in achieving 2-dimensional growth of highly mismatched InP/GaAs heterostructures from the initial stages. The structural characterization of the layers has been carried out by conventional and high resolution transmission electron microscopy and high resolution x-ray diffractometry. 60-degrees type misfit dislocations have been observed at the heterointerface in all the structures investigated. As the layer thickness increases, neighboring 60-degrees dislocations can react to form 90-degrees edge type dislocations. Planar defects extending into the layers along the {111} planes have also been observed. Finally, the elastic strain relaxation has been correlated with the nature and density of the observed crystal defects.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
