High‐Resolution X‐Ray Diffraction of III–V Semiconductor Thin Films

In this chapter, we will address the structural characterization of III–V semiconductor thin films by means of HRXRD. We first give an overview on the basic experimental apparatus and theory element of this method. Subsequently, we treat several examples in order to determine the effect of doping, composition and strain on structural properties of crystal. Analysed layers were grown by metal organic vapour phase epitaxy (MOVPE). Films treated as examples are selected in order to bring the utility of characterization technique. Here, we investigate GaAs/GaAs(0 0 1), GaAs:C/GaAs(0 0 1), GaN/Si(1 1 1), GaN:Si/Al2O3(0 0 1), GaAsBi/GaAs(0 0 1) and InGaAs/GaAs(0 0 1) heterostructures by using different scans for studying numerous structural layers and substrate parameters. Different scan geometries, such as ω‐scan, ω/2θ‐scan and map cartography, are manipulated to determine tilt, deformation and dislocation density induced by mismatch between layer and substrate. This mismatch is originated from the difference between the chemical properties of two materials generated by doping or alloying. Such HRXRD measurements are explored through the angular spacing between peaks of the substrate and layer. The half of full width maximum (HFWM) of peak layer intensity is a crucial qualitative parameter giving information on defect density in the layer