Effect of Ta doping on the characteristic features of spray-coated SnO2

Abstract In present work, undoped and Ta-doped SnO 2 thin films were fabricated via a simple and cheap spray pyrolysis technique. The Ta-doping level was varied from 0 at.% to 5 at.% in the step of 1 at.%. Large pyramidal and small densely-packed tetragonal SnO 2 particles were observed by X-ray diffraction and scanning electron microscope. Atomic force microscope analysis indicated that root mean square roughness values of films changed from 26.7 nm to 51.6 nm with Ta-doping. The electrical and optical measurements revealed that the films had a degenerate n-type semiconductor property. The resistivity, sheet resistance, carrier concentration, mobility, and optical band gap values of films varied between 1.11 × 10 − 2 Ω cm–2.35 × 10 − 3 Ω cm, 130.66 Ω/□–26.97 Ω/□, 2.72 × 10 19 cm − 3 –1.12 × 10 20 cm − 3 , 20.68 cm 2 V − 1 s − 1 –30.78 cm 2 V − 1 s − 1 , and 3.43 eV–3.94 eV, respectively. As a result of this study, it is concluded that characteristic properties of SnO 2 can be greatly improved with Ta-doping.