HIGH-CRYSTALLINITY SR1-XCUOY FILMS GROWN BY MOLECULAR-BEAM EPITAXY USING A MASS-SEPARATED LOW-ENERGY O+ BEAM

High-crystallinity films of the Sr1-xCuOy infinite-layer oxide were gr own by molecular beam epitaxy combined with a mass-separated low-energ y oxygen ion (O+) beam as the oxygen source. The film growth was carri ed out under an ultralow background partial pressure of molecular oxyg en, estimated to be less than 2 x 10(-11) Torr during growth. Reflecti on high-energy electron diffraction patterns of the films showed well- defined Kikuchi lines. Precise measurement of the rocking curves for t he films resulted in sharp peaks with a full-width at half-maximum of 0.016 degrees.