In situ pulsed laser deposition of large-area ceramic and multilayer films for applications in industry

High-quality superconducting films have been deposited onto 2 in. diameter substrates in a large-area pulsed laser deposition (PLD) system incorporating a novel pseudoblackbody radiation heater. A KrF laser (λ=248 nm) was rastered across the radius of a rotating target and a slot in the blackbody heater collected the ablation plume onto a rotating substrate holder. Critical temperatures of >90 Kwith critical current densities of 2–4 MA/cm2 were measured across a 2 in. diam YBa2Cu3O7−δ(YBCO) film deposited on an LaAlO3(LAO) substrate. Metal atom concentrations were measured by Rutherford backscattering spectrometry to be nearly stoichiometric and the film thickness uniformity was ±7% about the mean. Purely c-axis orientation was observed in the x-ray diffraction patterns. A multilayer LAO/YBCO film was deposited in situ on an MgO substrate using a large-area target load-lock chamber and exhibited good crystalline quality. YBCO films deposited onto both sides of a 1 in. square by 0.010-in.-thick MgO substrate were patterned and fabricated into a four-channel microwave receiver operating near 10 GHz. The receiver exhibited low loss and good frequency selectivity at 77 K.