CuxS thin ﬁlms, 80 nm thick, are deposited by vacuum thermal evaporation of sulfur-rich powder mixture,Cu2S:S (50:50 wt.%) with no intentional heating of the substrate. The process of deposition occurs at verylow deposition rates (0.1-0.3 nm/s) to avoid the formation of Cu or S-rich ﬁlms. The evolution of CuxS ﬁlms surface properties (morphology/roughness) under post deposition mild annealing in air at 270 °Cand their integration in a thin ﬁlm transistor (TFT) are the main objectives of this study. Accordingly, Scan-ning Electron Microscopy studies show CuxS ﬁlms with different surface morphologies, depending on thepost deposition annealing conditions. For the shortest annealing time, the CuxS ﬁlms look to be constructedof grains with large dimension at the surface (approximately 100 nm) and consequently, irregular shape. Forthe longest annealing time, ﬁlms with a ﬁne-grained surface are found, with some randomly distributed largeparticles bound to this ﬁne-grained surface. Atomic Force Microscopy results indicate an increase of theroot-mean-square roughness of CuxS surface with annealing time, from 13.6 up to 37.4 nm, for 255 and 345 s, respectively. The preliminary integration of CuxS ﬁlms in a TFT bottom-gate type structure allowedthe study of the feasibility and compatibility of this material with the remaining stages of a TFT fabricationas well as the determination of the p-type characteristic of the CuxS material.