ZnO/(ZnMg)O-based semiconductors are discussed for applications as optical devices emitting in the blue and ultraviolet wavelength range. Many basic properties of these heterostructures are not known, hence structure analysis can give valuable information.
We investigate in joint projects with the group of Prof. Dr. Martin Eickhoff/JLU Gießen the polarity, defect structure and composition of (ZnMg)O/ZnO heterostructures, which are either grown on sapphire or on ZnO substrates. The TEM techniques used include convergent beam electron diffraction, weak beam dark field imaging and energy dispersive X-ray spectroscopy.
The structure and composition of the layers is correlated to growth conditions as well as to optoelectronic properties.