Structural, Morphological, Optical, and Elemental Properties of the Low‐Temperature‐Deposited Amorphous Gallium Oxide Thin Film

In this work, amorphous gallium oxide (a‐Ga 2 O 3 ) thin films were deposited by pulsed laser deposition (PLD) and systematically characterized. Scanning electron microscopy reveals a uniform and smooth surface, while X‐ray diffraction confirms the amorphous nature of the thin film. X‐ray photoelectron spectroscopy reveals lattice and nonlattice oxygen components, together with lower‐binding‐energy Ga 3 d components associated with oxygen‐reduced Ga states, supporting a locally oxygen‐deficient chemical environment. Direct‐allowed Tauc analysis yields an optical bandgap of approximately 4.29 eV. Combined with the VBM located 2.80 eV below E F , the CBM is estimated to lie approximately 1.49 eV above E F . These results establish a self‐consistent band diagram linking the amorphous structure, defect chemistry, and energy level distribution of a‐Ga 2 O 3 .