Modifying ALE grown In2O3 films by benzoyl fluoride pulses

Indium oxide thin films grown at 500°C by atomic layer epitaxy from InCl3 and water were modified by benzoyl fluoride pulses. A broad minimum in resistivity was found when the number of the benzoyl fluoride containing cycles were 6–15% of total. The lowest resistivities were 4–5×10−4 Ωcm. Fluorine contents studied by nuclear resonance broadening method were below 0.02 at% in all the films, which is far too low to explain the measured carrier concentrations 2–3×1020 cm−3. This leads to an assumption that rather than acting as a fluorine source, the benzoyl fluoride modifies the In2O3 structure creating additional oxygen vacancies which serve as sources of the charge carriers. The films had cubic In2O3 structure and optical transparencies over 90%.