Flexible Transparent Electrodes Formed from Template-Patterned Thin-Film Silver.

We report template-patterned, flexible Transparent Electrodes (TEs) formed from an ultrathin silver film on top of a commercial optical adhesive - Norland Optical Adhesive 63 (NOA63). NOA63 is shown to be an effective base-layer for ultrathin silver films that advantageously prevents coalescence of vapour-deposited silver atoms into large, isolated islands (Volmer-Weber growth), and so aids the formation of ultrasmooth continuous films. 12-nm silver films on top of free-standing NOA63 combine high, haze-free visible-light transparency (T ≈ 60% at 550 nm) with low sheet-resistance ( R s ${\mathcal{R}}_s$ ≈ 16 Ω/sq.), and exhibit excellent resilience to bending, making them attractive candidates for flexible TEs. Etching the NOA63 base-layer with an oxygen plasma before silver deposition causes the silver to laterally segregate into isolated pillars, resulting in a much higher sheet resistance than silver grown on pristine NOA63 ( R s ${\mathcal{R}}_s$  > 8 × 10 6  Ω/sq.). Hence, by selectively etching NOA63 before metal deposition, insulating regions may be defined within an otherwise conducting silver film, resulting in a differentially conductive film that can serve as a patterned TE for flexible devices. Transmittance may be increased (to 79% at 550 nm) by depositing an antireflective layer of Al 2 O 3 on the Ag layer at the cost of reduced flexibility. This article is protected by copyright. All rights reserved.