Akademik Veri Yönetim Sistemi
Physica Status Solidi (A) Applications and Materials Science, cilt.223, sa.11, 2026 (SCI-Expanded, Scopus)
The scarcity and rising cost of indium drive the search for indium-free transparent conducting oxides (TCOs). Ta-doped SnO2 (Ta:SnO2) is a promising candidate due to its stable Ta5+ state and resonant doping behavior. In this study, Ta:SnO2 thin films are fabricated by pulsed laser deposition at room temperature, and the effects of deposition pressure (4–40 μbar), Ta doping concentration (2 and 7 wt% Ta2O5:SnO2 targets), and ex situ annealing temperature (300°C–500°C) are systematically investigated. XPS and Hall effect analyses confirm that postdeposition annealing at ≥400°C effectively activates Ta5+ dopants in films grown at low pressure (4–9 μbar), as evidenced by a concurrent increase in free carrier density despite the reduction of the surface-adsorbed oxygen signature in XPS, suggesting vacancy annihilation and surface reoxidation. Successful dopant activation enables low resistivities, with an optimized resistivity of 1.9 × 10−3 Ω cm achieved in films deposited using the 2 wt% target at 9 μbar and postannealed at 500°C, while maintaining >80% average visible to near-infrared (vis–NIR) transmittance. While 500°C is not yet device-compatible, this work motivates the exploration of postdeposition treatments that can locally crystallize and activate dopants in indium-free TCOs without affecting the adjacent layers of the device.