Large area pulsed laser deposition of YBCO thin films

A special PLD-setup for large area deposition of homogeneous YBa2Cu3O7-x (Y BCO) thin films and buffer layers as large as 7 cm x 20 cm will be presente d. A new concept for homogeneous large area substrate heating and the influ ence of the deposition rate on the film properties will be discussed. YBCO is deposited on r-plane sapphire substrates (10 cm x 10 cm) as well as on s maller (2 inch O, 1 cm x 1 cm) SrTiO3, MgO, LaAlO3, and on yttria stabilize d ZrO2 substrates distributed over the deposition area. The homogeneity of the deposited YBCO films concerning structural and electrical properties is investigated by XRD, RBS/Channeling, and spatially resolved inductive meas urements of Te and Jc, The variation of Je on a 2 inch MgO wafer is less th an +/-9 %, the mean c-axis length is 11.681 Angstrom, the FWHMs of the (005 ) rocking curves are 0.4 degrees and the channeling minimum yield chi(min) varies between 3.7 % and 4.9 % over the 2 inch wafer. The Je values of YBCO on 7 cm x 20 cm in situ buffered sapphire substrates are (2.0 +/- 0.4 MA/c m(2)) at T = 77 K and B = 0 T.