Abstract: In a method of patterning superconducting thin films such as YBaCuO, based on the inhibition of superconductivity by intermixing an impurity, such as silicon, with superconductor material, a thin film of silicon is formed on a magnesium oxide substrate and then patterned, by laser direct-writing for example, to correspond to a desired pattern of superconducting lines. Multilayered YBaCuO thin films are then deposited over the patterned silicon film and annealed using rapid thermal annealing at a temperature of 980.degree. C. maintained for a period in the range from 30 to 90 seconds. The rapid annealing results in intermixing of silicon and YBaCuO in regions of the film between the lines of the pattern which, in turn, causes these regions to become insulating, and at the same time causes the YBaCuO film over the line pattern to become superconducting.