of thermal to electrical energy and vice versa. The state-of-the-art material for thermoelectric generators (TEG) is bismuth telluride (Bi 2 Te 3); however, its application is limited due to its high costs and tendency to oxidize at elevated temperatures. Copper-iron-oxides are a thermally stable promising alternative due to the low costs of the raw materials, their high Seebeck coefficient, and their high electrical conductivity. The PAD method enables to form dense nanocrystalline ceramic films on a variety of substrates with high deposition rates. [16-18] In contrast to all other ceramic processing routes, even moisture-sensitive ceramics, or ceramics with high sintering temperatures can be fabricated at room temperature (RT). [11] Besides the dry ceramic powder, neither additional binders nor other liquids are needed. The ceramic particles are accelerated towards a substrate by a pressure difference. The kinetic energy of the particles is converted into bonding energy during their impact on the substrate and comes along with the reduction of the crystallite size and formation of microstrain within the atomic lattice. [19-21] Particle fracturing occurs along the grain boundaries and within the grains generating temporarily unsaturated surface bonds that cause an excellent adherence of the particles. [22] Despite all the positive aspects of the powder aerosol deposition summarized in Figure 1, a major disadvantage in the as-deposited state that all PAD films have in common is the reduced electrical conductivity of the films. A thermal annealing step is necessary to reduce the mechanical stress of the film and to restore the electrical properties so that they reach bulk values. Exner et al. recently found out that the required annealing temperature in the furnace depends on the melting point of the functional ceramic materials, though it is significantly lower than the typical sintering temperatures. [23] In contrast, laser-based annealing could provide additional advantages like a reduced annealing time or a targeted local property change as it was shown by Palneedi et al. for PZT (Pb(Zr,Ti)O 3) [24-30] and Shinonaga et al. for TiO 2. [31-33] In this study, we investigated the influence of laser irradiation on the properties of a nanocrystalline thermoelectric film. Tin doped copper-iron-oxide respectively copper delafossite (CuFe 0.98 Sn 0.02 O 2), which is known for its good thermoelectric properties and is processability by PAD, [15,34] was synthesized by the mixed-oxide-route. Films were fabricated by powder aerosol deposition method. After deposition, the films were annealed with a frequency tripled Nd:YAG laser (λ = 355 nm) and its influence on the microstructure and the electrical properties was examined by optical and electrical measurements. Powder aerosol deposition (PAD) is a unique coating method that allows the fabrication of dense ceramic films on a variety of substrates at room temperature. This spraying process can produce film thicknesses of several micrometers within minutes without the use of...