Alumina Aluminum oxide Aspect ratio Atomic layer deposition Atomic layer etching Atomic-layer deposition Atoms Etch rates Etching Etching process Fluorine compounds Hafnium oxides In-Situ Study Oxide films Photoelectrons Photons Process pressure Semiconductor devices Sequential reaction Spectroscopic analysis Spectroscopic ellipsometry Surface reactions Temperature distribution Thin films Thin-films Trimethylaluminum X ray photoelectron spectroscopy X-ray photoelectrons