Formation and evolution of antiphase boundaries during epitaxial growth of partially ordered Ga_(0.5)In_(0.5)P

摘要

The antiphase boundaries in CuPt_B-type ordered Ga_(0.5)In_(0.5)P layers grown by metal-organic vapor phase epitaxy on GaAs(001) substrates misoriented towards [1(1-bar)0] have been investigated at the interface to the buffer layer by plan-view transmission electron microscopy. The patterns of antiphase boundaries indicate that the growth of Ga_(0.5)In_(0.5)P starts by the formation of ordered islands rather than by step-flow as believed so far. Furthermore, the connection between the antiphase boundaries and the surface undulations have been studied by transmission electron microscopy and atomic force microscopy. No direct spatial coincidence of the antiphase boundaries and surface features has been found, especially by plan-view transmission electron microscopy which allows imaging of both at the same time.