NOVELTY - A water-free composition is applied to a substrate. This is dried as necessary, then converted into an indium oxide-containing layer. In the applied composition there is at least one solvent and an indium oxo alkoxide of the generic formula: MxOy(OR)z(O(R'O)CH)aXb(R''OH)d in which x=2-25, y=1-10, z=3-50, a=0-25, b=0-20, c=0-1, d=0-25, M=In, R, R' and R'' are organic radicals and X=F, Cl, Br or I. Variant formulae are provided to specify the indium oxo alkoxide in the composition.    USE - To produce layers containing indium oxide, especially to make semiconductor components. The layers are used to manufacture electronic components, especially transistors, diodes, sensors and solar cells (claimed).    ADVANTAGE - Indium (III) oxide, In2O3 is a promising semiconductor because of the large band gap between 3.6 and 3.75 eV. A new method of producing indium oxide-containing layers from non-aqueous solutions is proposed. The method avoids use of high vacuum. Energy is required for conversion of the precursors or educts. This is readily introduced and evenly distributed using the methods described. Disadvantages of sol-gel techniques are avoided. Indium oxide layers are produced with uniform and reproducible stoichiometry, greater homogeneity and excellent electrical performance.    DETAILED DESCRIPTION - Indium oxo alkoxide is the sole metal oxide precursor used in the process. It is present in proportions of 0.1-15 wt% referred to the total mass of the water-free composition. The solvent is aprotic or weakly protic. It is selected from: methanol, ethanol, isopropanol, tetrahydro furfuryl alcohol, tertiary butanol and toluene. The viscosity of the composition is 1 mPa.s to 10 Pa.s. The substrate is glass, silicon, silicon oxide, a metal- or transition metal oxide, a metal or a polymer. The water-free composition is applied to the substrate using printing, spraying, rotary coating, immersion, meniscus coating, silt coating, slot-die coating, or curtain coating. The conversion is thermal, at temperatures exceeding 150 degrees C. Before, during or after conversion, the layer is irradiated with UV-, IR or visible radiation. An INDEPENDENT CLAIM is included for the indium oxide layer produced.