Our group reported previously off-stoichiometric copper-chromium delafossite (Cu_2/3Cr_4/3O₂) with long chains of copper vacancies as source of high p-type electrical conductivity and adequate optical transparency. The small polaron conduction mechanisms present in this class of materials leads to low values of mobilities (< 0.1 cm²/ (V.s) – Bosman-Van Daal limit). One way to ameliorate this is to engineer the energetic band structure by the means of induced strain. For this purpose, delafossite thin films were grown by metal organic chemical vapour deposition (MOCVD) on substrates with different thermal expansions and to evaluate the effect of induced thermal strain on delafossite thin films (caused by the mismatch between the coefficients of thermal expansion of the substrate and the delafossite) was evaluated. Seebeck coefficient and resistivity measurements were performed on the range of 300-850 K. The Arrhenius relation has shown two different electrical conductivity behaviours over temperature with two distinct activation energies; this crossover point lies around the deposition temperature, where the transition from tensile to compressive strain takes place. These results might open the possibility of tunning the electrical properties of TCOs by engineering of the substrate-film interface.