ZnO	Zinc Oxide
RE	Rare-Earth
La	Lanthanum
Er	Erbium
Sm	Samarium
XRD	X-ray Diffraction
SEM	Scanning Electron Microscopy
EDX	Energy Dispersive X-ray Spectroscopy
UV–Vis	Ultraviolet–Visible Spectroscopy
PL	Photoluminescence
Eg	Optical Bandgap Energy
λ	Wavelength
D	Crystallite Size
ε	Microstrain
δ	Dislocation Density
τZnO	Crystallite Size of ZnO phase from Rietveld refinement
τsecondary	Crystallite Size of Secondary Phase
εZnO	Microstrain of ZnO phase from Rietveld refinement
εsecondary	Microstrain of Secondary Phase
nm	Nanometer
eV	Electron Volt
at.%	Atomic Percent
Tauc plot	Graphical Method to Estimate Bandgap from UV–Vis Absorption
O2	Molecular Oxygen
RE:ZnO	Rare-Earth-Doped ZnO Thin Film