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Thin, transparent silver films sandwiched between dielectric layers are a versatile and high performance transparent electrode technology. Using direct laser interference patterning (DLIP), we are able to structure thin metal films by direct ablation in a fast, single step process. To achieve beneficial pattern and ablation properties, different sublayers of MoOx, Au, Al, Cr, or organics below the silver film and different laser power densities and pulse numbers are investigated. The resulting hexagonally periodic array of apertures shows improved transmittance and sheet resistance. For the best parameter set, the silver network contains little superfluous material at the joints and benefits from partial recrystallization, improving the conductivity. The nanostructured thin‐films have great potential to be combined with dielectric antireflection layers as transparent electrode for any thin‐film optoelectronic devices.

In the search for alternative materials to replace indium-tin-oxide in transparent electrodes we have structured copper and aluminum thin films (between 5 an 40 nm) for tailoring their optical properties. Micrometer scaled holes were produced using the direct laser interference patterning (DLIP) technique. We compared the optical and electrical parameters of nanosecond and picosecond processed thin films. It was found that the optical transmittance of the structured layers was relatively increased between 25 to 125% while the electrical resistance was marginally influenced. In addition, the laser treatment enhanced the diffuse to total transmission ratio (HAZE) by values ranging from 30 to 82% (relative) as a potential advantage of μm structuring. The results also show that both of the studied metals succeed to match the target which is set by typical applications of indium thin oxide (ITO) films. Furthermore, numerical simulations are performed in order to understand the ablation process of thin film material for ps and ns pulses.

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