Abstract:
Hard X-ray photoelectron spectroscopy (HAXPES) provides a powerful depth-resolved approach for probing buried chemical states and electrostatic band profiles in functional semiconductor structures. In this talk, I will present our recent use of angle-resolved HAXPES to reveal opposite band-bending profiles in polarization-graded N-polar InGaN/GaN nanorods, clarifying how internal electrostatics governs carrier redistribution, nanogenerator output, and illumination-dependent screening behavior. Building on this demonstration, I will further discuss our proposed synchrotron-based HAXPES platform for next-generation semiconductor interface metrology, where angle-varied measurements, combined with physics-constrained reconstruction, can extract buried chemical states, band alignment, potential steps, and device-relevant interface descriptors in advanced multilayer and three-dimensional device stacks. This work highlights HAXPES as a key bridge between buried-interface physics and practical semiconductor device/process optimization.
Keywords – Hard X-ray photoelectron spectroscopy (HAXPES), III-nitride nanostructures, Si devices