Highly Conducting and Highly Transparent Oxide/Metal/Oxide Structures for Ultraviolet-C Light Sources Utilizing a Thin Cu Wetting Interlayer.

The ZnMgBeO/Cu/Ag/ZnMgBeO multilayer structures were designed, sputter-deposited at room temperature, and characterized in detail. Results indicated that the multilayer structures with high transmission (higher than 90% at the visual wavelength range) can be readily obtained by simply inserting a thin (∼5 nm) Cu wetting layer, which renders the thin Ag layers (∼5 nm thick) continuous and smooth. It was also observed that the optical absorption edges of the multilayer structures increase as the energy band-gaps of the top/bottom oxide layers increase and the multilayer structures with the energy band gap of ∼6.0 eV can be obtained by employing the ZnMgBeO layers, with an excellent resistivity of ∼1.7 × 10 Ω cm. These results represent a significant improvement over the previous reports and the first report on the design and fabrication of the highly conducting transparent materials for the UV-C application.