IN-SITU SYNCHROTRON X-RAY STUDIES OF EPITAXIAL STRAINED-LAYER GROWTH-PROCESSES

The work described here uses, for the first time, in situ synchrotron X-ray topography to study misfit dislocation introduction processes during the growth of strained InGaAs on (001) GaAs. The central importance of GaAs substrate threading dislocations in the initial relaxation phase is highlighted. Following this phase, these studies clearly demonstrate that a significant increase in epilayer thickness is then required to activate additional dislocation sources for further stress-relief. The observation of the different relaxation regimes is described in detail.