Title :
Low-pressure oxidation of YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films in purified ozone
Author :
Sawa, A. ; Kosaka, S. ; Obara, H. ; Aoki, K.
Author_Institution :
Electrotech. Lab., Ibaraki, Japan
fDate :
3/1/1993 12:00:00 AM
Abstract :
The oxidation of YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films with purified ozone has been studied by in-situ resistivity measurements during annealing, and the oxidizing activity of ozone was compared with that of molecular oxygen. The experimental results suggest that ozone partial pressure, which yields the YBa/sub 2/Cu/sub 3/O/sub 7-x/ phase with a certain oxygen content, is about 5 orders of magnitude smaller than the pressure of molecular oxygen which yields the same oxygen content of YBa/sub 2/Cu/sub 3/O/sub 7-x/. The pressure-temperature phase diagram in ozone was also generated from these results. The YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin film with a superconducting transition temperature of 86 K was deposited at an ozone pressure of 9*10/sup -5/ Torr.<>
Keywords :
annealing; barium compounds; high-temperature superconductors; oxidation; phase diagrams; superconducting thin films; superconducting transition temperature; surface chemistry; yttrium compounds; 86 K; 9*10/sup -5/ torr; YBa/sub 2/Cu/sub 3/O/sub 7- delta /; annealing; high temperature superconductors; in-situ resistivity; low pressure oxidation; oxidizing activity; ozone partial pressure; pressure-temperature phase diagram; purified ozone; superconducting transition temperature; thin films; Conductivity measurement; Gold; Oxidation; Plasma temperature; Sputtering; Superconducting thin films; Superconducting transition temperature; Temperature dependence; Transistors; Yttrium barium copper oxide;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
