SiC is set to enable a new era in power electronics impacting a wide range of energy technologies, from electric vehicles to renewable energy. Its physical characteristics outperform silicon in many aspects, including band gap, breakdown field, and thermal conductivity. The main challenge for further development of SiCbased power semiconductor devices is the quality of the interface between SiC and its native dielectric SiO 2 . High temperature nitridation processes can improve the interface quality and ultimately the device performance immensely, but the underlying chemical processes are still poorly understood. Here, we present an energy-dependent hard X-ray photoelectron spectroscopy (HAXPES) study probing non-destructively SiC and SiO 2 and their interface in device stacks treated in varying atmospheres. We successfully combine laboratory-and synchrotron-based HAXPES to provide unique insights into the chemistry of interface defects and their passivation through nitridation processes.
The determination of atomic structures in surface reconstructions has typically relied on structural models derived from intuition and domain knowledge. Evolutionary algorithms have emerged as powerful tools for such structure...
HfO2 is an important high‐k dielectric and ferroelectric, exhibiting a complex potential energy landscape with several phases close in energy. It is, however, a strongly anharmonic solid, and thus describing its temperature‐dependent behavior is methodologically challenging. An approach based on self‐consistent, effective harmonic potentials (EHP) to study the potential energy surface (PES) of anharmonic materials is proposed. The introduction of a reweighting procedure enables the usage of unregularized regression methods by efficiently utilizing the information contained in every data point obtained from density functional theory. The approach is detailed and tested on the example of the high‐temperature cubic phase of HfO2. It is demonstrated how the correction term for the deviation between the EHP and the true PES can be calculated directly from the same sampling used for determining the EHP. The calculated temperature‐dependent physical properties are in agreement with existing experimental data, thereby opening for the predictive treatment of HfO2 over a wide temperature range.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.