  An experimental investigation was conducted to explore spectroscopic and
structural characterization of semiconducting yttrium oxide thin film deposited
at 623 K (+/- 5K) utilizing reactive pulsed direct current magnetron
sputtering. Based on the results obtained from both x-ray diffraction and
transmission electron microscope measurements, yttrium monoxide is very likely
formed in the transition region between {\beta}-Y2O3 and {\alpha}-Y2O3, and
accompanied by the crystalline Y2O3. Resulting from either the low energy
separation between 4d and 5s orbitals and/or different spin states of the
corresponding orbitals' sublevels, the stability of monoxide is most presumably
self-limited by the size of the crystal in thermodynamic terms. This behavior
develops a distortion in the structure of the crystal compared to the metal
oxide cubic structure and it also effectuates the arrangement in
nanocrystalline/amorphous phase. In addition to this, spectroscopic
ellipsometry denotes that the semiconducting yttrium oxide has the dominant,
mostly amorphous, formation character over crystalline Y2O3. Our purpose, by
means of the current findings, is to advance the understanding of formation
kinetics/conditions of yttrium with an unusual valency (2+).
