Title :
YBa/sub 2/Cu/sub 3/O/sub 7-x//SrTiO/sub 3/ bilayers for superconducting field effect devices by pulsed laser deposition
Author :
Doughty, C. ; Walkenhorst, A. ; Xi, X.X. ; Kwon, C. ; Li, Q. ; Bhattacharya, S. ; Findikoglu, A.T. ; Mao, S.N. ; Venkatesan, Thirumalai ; Spencer, N.G. ; Grace, W.R.
Author_Institution :
Dept. of Phys., Maryland Univ., College Park, MD, USA
fDate :
3/1/1993 12:00:00 AM
Abstract :
Materials issues relevant to the growth of high-quality YBa/sub 2/Cu/sub 3/O/sub 7-x//SrTiO/sub 3/ (YBCO/STO) bilayers for use in superconducting field-effect devices were studied. Different substrate materials and growth conditions were investigated. NdGaO/sub 3/ was determined to be the most promising substrate material due to its low surface roughness and good lattice match to YBCO. The electrical properties of ultrathin YBCO and YBCO/STO bilayers grown by pulsed laser deposition were also investigated as a function of substrate temperature. The optimized deposition temperature for 10-nm-thick YBCO was found to be 60 degrees C below that of thick (100-nm) films. STO overlayers with a dielectric constant of approximately=700 and a breakdown field of approximately=625 kV/cm were fabricated. The STO/YBCO interface was also studied.<>
Keywords :
barium compounds; field effect transistors; high-temperature superconductors; pulsed laser deposition; strontium compounds; superconducting junction devices; superconducting thin films; yttrium compounds; YBa/sub 2/Cu/sub 3/O/sub 7-x/-SrTiO/sub 3/; bilayers; electrical properties; high temperature superconductor; low surface roughness; substrate material; superconducting field effect devices; ultrathin; Lattices; Optical materials; Optical pulses; Pulsed laser deposition; Rough surfaces; Superconducting devices; Superconducting materials; Surface roughness; Temperature; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
