High-rate dual-target dc magnetron sputtering of "blue" electromagnetic Mo oxide

Mo oxide films were prepared by dual-target reactive DC magnetron sputtering under conditions leading to films that were blue in as-deposited state. The deposition rate for this “blue” Mo oxide was as high as 1.5 nm/s, to be compared to ∼0.85 and ∼0.1 nm/s for highly transparent Mo oxide films made with dual-target and single-target sputtering, respectively. Good electrochromic properties of the “blue” films evolved after ∼5 colour/bleach cycles in a Li+ conducting electrolyte.