The　tin　dioxide　(SnO2)　thin　films　in　this　work　were　prepared　by　using　plasma-enhanced　atomic　layer　deposition　(PEALD),　and　a　systematic　analysis　was　conducted　to　evaluate　the　influence　of　post-deposition　annealing　at　various　temperatures　in　a　nitrogen-hydrogen　mixed　atmosphere　on　their　surface　morphology,　optical　behavior,　and　electrical　performance.　The　SnO2　films　were　characterized　by　using　X-ray　diffraction　(XRD),　X-ray　photoelectron　spectroscopy　(XPS),　scanning　electron　microscopy　(SEM),　transmission　electron　microscopy　(TEM),　and　Hall　effect　measurements.　With　increasing　annealing　temperatures,　the　SnO2　films　exhibited　enhanced　crystallinity,　a　higher　oxygen　vacancy　(O-V)　peak　area　ratio,　and　improved　mobility　and　carrier　concentration.　These　enhancements　make　the　annealed　SnO2　films　highly　suitable　as　electron　transport　layers　(ETLs)　in　perovskite　solar　cells　(PSCs),　providing　practical　guidance　for　the　design　of　high-performance　PSCs.