Optical, electrical, and structural properties of Ta-doped SnO2 films against substrate temperature using direct current magnetron sputtering

Ta-doped SnO2 (TTO) films were deposited at 3 x 10(-3) Torr pressure from the 6 wt. % Ta2O5-doped SnO2 target at temperatures of 30-500 degrees C in Ar sputtering gas. The Ta dopants in the SnO2 host lattice were detected via X-ray photoemission, EDX mapping, and photoluminescence spectra. The Ta5+-Sn4+ substitution formed the O-O(x) at V-O(x), sites in the host lattice and the substitution occurred at deposition temperatures greater than 200 degrees C. The substitution leads to a decrease in the amount of V-O(x), in the SnO2 lattice corresponding to the preferred rutile SnO2 (110) lattice reflection in the X-ray diffraction patterns. The ultraviolet-visible transmittance in visible light was approximately 80%. The lowest resistivity achieved was 2.0 x 10(-3) Omega.cm, with a carrier concentration of 1.28 x 10(20) cm(-3) and carrier mobility of 24.5 cm(2)V(-1)s(-1). The integration of the TTO-400 film with (n- and p-) Si exhibited an excellent photoelectric effect.

Automated summary

The Ta-doped SnO2 films were deposited at different temperatures and the effects of Ta dopants on the lattice structure and electrical properties were investigated. The substitution of Ta in the SnO2 lattice was found to improve conductivity and optical transmittance, leading to an enhanced photoelectric effect when integrated with Si.