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The first transparent conductive oxide (TCO) was introduced by Karl Bädeker in 1907, more than 110 years ago. [1] It was a thin film of cadmium oxide (CdO) prepared by oxidizing a vacuum-sputtered film of cadmium metal. By the same method, the first film of tin oxide (SnO 2 ) was obtained in 1937 by Gerhard Bauer. [2] Currently, different TCOs are being employed in the optoelectronic industry such as aluminum-doped zinc oxide (AZO), indium-doped tin oxide (ITO), and fluorine-doped tin oxide (FTO). The latter has been extensively used as it possesses low fabrication costs compared to ITO because indium is a very scarce element on Earth, [3] high thermal resistance, and good electronic compatibility with many semiconductors. [4,5] To ensure the high performance of optoelectronic devices, two features are key for TCOs: high optical transmittance in the spectral range of interest and low electrical resistivity. Besides, a high level of diffuse spectral transmittance has been demonstrated to further enhance sunlight absorption in the photoactive material on many different solar cell technologies. [6][7][8][9][10] Particularly in FTO, numerous strategies were applied to achieve these goals, for instance, by changing the doping concentration of fluorine, [11] by performing a surface chemical etching, [12] by laser annealing, [13] or by laser ablation. [14,15] In the field of laser ablation, efforts have been carried out to develop different approaches to structure the surface without deteriorating the material's intrinsic properties, which could affect the optoelectronic performance of the device in which it will be employed. Saetang et al. [16] structured FTO with an infrared (IR) ns-pulsed laser, generating line-like structures by means of a stream of water between the laser source and the conductive film. The results showed a reduction of the burr height index of 62.5% (relative) which is a critical parameter to reduce the intermittency between different thin layers in solar cells. Moreover, Kim et al. [17] textured FTO for dye-sensitized solar cells (DSSCs) by using a continuous wave Nd:YAG infrared laser and obtained an 8.1% increase in the incident-photon-to-current efficiency (IPCE) compared to the solar cell based on unstructured FTO.Regarding laser techniques, direct laser interference patterning (DLIP) has become an industrial-compatible technique able to produce large-area periodic surface micro-and nanostructures on a broad range of materials. [18,19] Berger et al. [20] used DLIP to structure ZnO:B thin films with an UV ns-laser and achieved a

It is well known that the surface topography of a part can affect its function as well as its mechanical performance. In this context, we report on the surface modification of additive manufactured components made of Titanium 64 and Scalmalloy®, using Direct Laser Interference Patterning technique. In our experiments, a nanosecond-pulsed near-infrared laser source with a pulse duration of 10 ns was used. By varying the process parameters, periodic structures with different depths and associated roughness values are produced. Additionally, the influence of the resultant morphological characteristics on the wettability behaviour of the fabricated textures is investigated by means of contact angle measurements. The results demonstrated a reduction of the surface roughness of the additive manufactured parts (in the order of some tens of micrometres) and simultaneously the production of well-defined micro-patterns (in the micrometre range), which allow the wettability of the surfaces from 26° and 16° up to 93° and 131° to be tuned for Titanium 6Al 4V and Al-Mg-Sc (Scalmalloy®), respectively.

The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/adem.202101624.

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