Asymmetric Relaxation in Epitaxial Layers of III-V Compounds

Relaxation in a 3 μm epitaxial layer of GaAsSb on GaAs, a 1 μm layer of InGaAs on InP and an InGaAs superlattice on InP has been investigated by double crystal X-ray diffractometry and double crystal X-ray synchrotron topography and found to be asymmetric. The origins of assymetric relaxation are discussed and the sensitivity of diffractometry and topography to the detection of layer relaxation compared.