Optimization of YBa/sub 2/Cu/sub 3/O/sub 7-x/ thick films on yttria stabilized zirconia substrates

Abstract

This report describes the o p t i m i z a t i o n of the firing process used in the production o f Y B a 2 C~3 0 7 -~ thick films screen printed on y t t r i astabilized zirconia substrates. The highest c r i t i c a l current density (Jc) values were obtained b y employing a double layer printing technique i n which a single superconductive layer was printed onto a zirconia substrate and fired, followed by t h e subsequent deposition and firing of a s e c o n d superconductive layer. Using this procedure, t h i c k film superconductors with a superconductive transition temperature (T,) of 85K and a Jc of 1 3 0 A/cm2 were obtained by sintering the printed f i l m s at 950°C for 90 minutes, followed by a six hour oxygen annealing treatment at 600°C. S p e c i m e n s sintered for comparable periods of time at 940 and 960°C did not exhibit superconductive b e h a v i o r above 77K due to either incomplete microstructural development or thermal decomposition of t h e superconductive phase respectively.