Characterization of 3D semiconductor nanostructures using ultra-high-resolution STEM-CL at He-temperatures

Synopsis

For a comprehensive understanding of complex semiconductor nano-heterostructures and the physics-archive of devices based on them, a systematic determination and correlation of the structural, chemical, electronic, and optical properties on a true nanometer scale is essential. Luminescence techniques belong to the most sensitive, non-destructive methods of semiconductor research. The combination of luminescence spectroscopy - in particular at liquid He temperatures - with the high spatial resolution of a scanning transmission electron microscopy (STEM) as realized by the technique of low temperature scanning transmission electron microscopy cathodoluminescence microscopy (STEM-CL), provides a unique and extremely powerful tool for the almost atomic scale optical characterization of semiconductor nanostructures. For GaN a spatial resolution of  < 1 nm at room temperature and  < 5 nm at 10 K is achieved.