Thin films of cadmium oxide (CdO) doped with 1.5 wt pct samarium were prepared by a vacuum evaporation on glass and Si wafer substrates. The prepared films were annealed in nitrogen gas at 200 degrees C, 250 degrees C, and 300 degrees C and characterised by the X-ray fluorescence and diffraction. It was observed that the N-annealing of CdO:Sm films has no a considerable effect on their CdO cubic crystalline parameters, crystallinity, and energy gap. However, the electrical measurements show that CdO:Sm is an n-type degenerate semiconductor and the nitridation increases its conductivity and carrier concentration. These results were explained according to the available models. In general, the low-temperature nitridation is a useful complementary operation for the production a better transparent conducting oxide TCO. (C) 2009 Elsevier B.V. All rights reserved.