Room-temperature synthesized copper iodide thin film as degenerate p-type transparent conductor with a boosted figure of merit.
A degenerate p-type conduction of cuprous iodide (CuI) thin films is achieved at the iodine-rich growth condition, allowing for the record high room-temperature conductivity of ∼156 S/cm for as-deposited CuI and ∼283 S/cm for I-doped CuI. At the same time, the films appear clear and exhibit a high transmission of 60-85% in the visible spectral range. The realization of such simultaneously high conductivity and transparency boosts the figure of merit of a p-type TC: its value jumps from ∼200 to ∼17,000 MΩ-1Polycrystalline CuI thin films were deposited at room temperature by reactive sputtering. Their electrical and optical properties are examined relative to other p-type transparent conductors. The transport properties of CuI thin films were investigated by temperature-dependent conductivity measurements, which reveal a semiconductor-metal transition depending on the iodine/argon ratio in the sputtering gas.
Institut für Experimentelle Physik II, Universität Leipzig, 04103 Leipzig, Germany yangchangyc@gmail.com.
Chang
0000-0002-1380-9533
C
Yang
Institut für Experimentelle Physik II, Universität Leipzig, 04103 Leipzig, Germany.
Max
M
Kneiβ
Institut für Experimentelle Physik II, Universität Leipzig, 04103 Leipzig, Germany.
Michael
M
Lorenz
Institut für Experimentelle Physik II, Universität Leipzig, 04103 Leipzig, Germany.
Marius
0000-0001-7554-182X
M
Grundmann
copper iodide thin film; figure of merit; p-type transparent conductor; reactive sputtering; room-temperature growth