Effects of Mg content and thermal treatments on optoelectronic and bending properties of transparent conductive indium tin oxide/AgMg bi-layer film

Abstract Thin film metallic glass of various Ag-Mg composition layers deposited by co-sputtering was utilized as the metallic layer in the transparent conductive electrode of indium tin oxide (ITO)/AgMg (IAM). A series of IAM system has been established, the relation between optoelectronics property and compositional variation was revealed. The optical transmittance and electrical properties of the bi-layered structure before and after furnace or laser annealing were investigated. The relative change in the resistivity of IAM after cycling bending stress was also determined to ensure the robustness of the bi-layered structure. The IAM could show the optical transmittance of 76.4% at 550 nm and sheet resistivity of 21.6 Ω/□. Furnace annealing at 200 °C improved the figure of merit for all IAM films by 3∼48. Upon furnace thermal treatment, ITO/10 nm Ag75Mg25 films reached the highest figure of merit of 1.24 × 10−2 Ω−1 with an optical transmittance of 83.0% and a sheet resistivity of 12.5 Ω/□. The relative change in resistivity (ΔR/Ro) of the as-deposited IAM, following fatigue testing (10,000 cycles) with a bending strain e = 0.357%, equals 0.42, which was remarkably lower than that of a 30 nm ITO film (ΔR/Ro = 0.93) on a polyethylene terephthalate flexible substrate.