Optimized Antimony‐Doped Tin Oxide Thin Films With Enhanced Electrical Properties for Low‐Emissivity Architectural Coatings

Antimony‐doped tin oxide (ATO) thin films were deposited by aerosol‐assisted chemical vapor deposition (AACVD) and systematically investigated to establish correlations between doping level, defect chemistry, structural properties, and optoelectronic performance. X‐ray diffraction confirmed that all films crystallized in the cassiterite structure without secondary phases, indicating successful incorporation of Sb into the SnO 2 lattice. Moderate Sb doping significantly reduced film resistivity due to increased carrier concentration, while excessive doping resulted in increased resistivity and reduced mobility. Optical measurements revealed high visible transmittance and low haze, together with a characteristic bluish coloration at increased doping levels, attributed to free‐carrier absorption. Importantly, the films exhibited selective infrared blocking, positioning ATO as a promising candidate for solar‐control coatings. The optoelectronic performance was assessed using Haacke's figure of merit, with optimized samples demonstrating a favorable balance between electrical conductivity and optical transparency. CIE Lab* color coordinates were used to quantitatively evaluate the color appearance of the films. The controllable blue‐gray optical tint, combined with infrared heat shielding, positions AACVD‐deposited ATO films as promising candidates for low‐emissivity architectural glazing, as well as transparent electrode applications in optoelectronic devices.