Large-area and double-sided pulsed laser deposition of Y-Ba-Cu-O thin films applied to HTSC microwave devices

Pulsed laser deposition (PLD) of YBa/sub 2/Cu/sub 3/O/sub 7-x/ (YBCO) thin films on both sides of 3-inch diameter sapphire wafers and LaAlO/sub 3/ (LAO) cylinder substrates, respectively, is a basic and flexible technique in order to optimize microwave bandpass filters for wireless communication systems. The large-area and double-side PLD technique allows homogeneous and reproducible YBCO deposition on both substrate sides with inductively measured critical current densities j/sub c/ of 3/spl times/10/sup 6/ to 5/spl times/10/sup 6/ A/cm/sup 2/ at 77 K with a YBCO thickness of 350 nm to 600 nm. Selected results of compositional, structural, electrical, and microwave characterization of the PLD-YBCO films are reported.