Transparent conductive Ga-doped ZnO/Cu multilayers prepared on polymer substrates at room temperature

In order to improve the transparency and durability of the Cu films deposited on polycarbonate (PC) substrates, a Ga-doped ZnO (GZO) layer could be deposited directly onto the Cu film. Compared with a single-layered GZO film, the GZO/Cu multilayer coatings have much lower sheet resistance and much thinner thickness. In our work, GZO/Cu multilayers were deposited by magnetron sputtering on PC substrates at room temperature. The structural, electrical, and optical properties of multilayers were investigated at various thicknesses of the Cu and GZO layers. As the Cu layer thickness increases, the resistivity decreases. As the GZO layer thickness increases, the resistivity increases. And we obtained that the transmittance of the GZO/Cu multilayer coatings was higher than that of the single Cu layer. The lowest resistivity of 5.7×10−5 Ω cm with a carrier concentration of 3.25×1022 cm−3 was obtained at the optimum Cu (12 nm) and GZO (10 nm) layer thickness. The best figure of merit φTC is 4.66×10−3 Ω−1 for the GZO(30 nm)/Cu(12 nm) multilayer.