General Electric Co. said its scientists have put a superconducting film on a silicon chip and gotten it to work at temperatures warmer than liquid nitrogen, the first such achievement. The matching of a superconductor and silicon is considered important because of silicon's dominance in the microelectronics field, GE said in an announcement for release Thursday. ``Virtually all of the world's microchips are made from silicon, so if you want to use the new superconducting materials in any way in microelectronics, it is advantageous to be able to deposit them on this substrate,'' Antonio Mogro-Campero, who did the research along with Larry G. Turner, said in a statement. Previous attempts to apply a superconducting film on silicon had failed because the layers mixed in the process of heating the film, known as annealing. Researchers at GE's research center in Schenectady, N.Y., solved the problem by using a buffer layer of zirconia, a heat-resistant metallic oxide. GE said the thin film remained superconducting _ that is, with zero loss of energy to resistance _ at temperatures as high as 310 degrees below zero Fahrenheit, 10 degrees above the point at which nitrogen becomes liquid.
