Titanium oxide layers were prepared by sputter deposition with plasma emission monitoring in the whole stoichiometry range between Ti and TiO2 without and with substrate heating to 240 degrees C. The layers were characterized with regard to their crystal structure and specific resistance. Optical constants were determined in the spectral range between 240 nm and 38 mu m. The thermochromic behavior of a prepared Ti2O3 layer was measured and compared to calculations for bulk material.