THE EFFECT OF COMPOSITION IN CONTROLLING THE O-CONTENT IN (BIPB)(2)SR2CA2CU3OY THIN-FILMS

Journal article

The effect of composition in controlling the O content of textured polycrystalline Bi2-xPbxSr2Ca2Cu3Oy thin films grown on MgO(001) substrates by RF magnetron sputtering has been studied. Films of composition Bi1.5Pb1.5Sr1.25Ca1.85Cu3Ox sintered at high temperatures (862 °C) for 30 min in air were cooled down to different low temperatures (700-150 °C) with a cooling rate of 1 °C min-1 and subsequently air quenched to room temperature. A small decrease of Tc from 109.5 K to 105.5 K was observed with decreasing quenching temperature, i.e. with increasing O content. The same effect has also been observed in films sintered and cooled in different partial O2 atmospheres. However, it was found that this is not the case for slightly Bi-rich (Bi:1.82) as-deposited film compositions and films doped with excess Pb (Pb: more than 0.26 in sintered films). It is suggested that the O content can be changed at ambient pressure in air for optimization of the charge carrier concentration. The contradictory results in the literature concerning the variation of Tc with O content for the Bi-2223 phase can now be understood as being due to differences in the film composition or initial O content of the films.

Authors: Guldeste, A; Grovenor, C; Goringe, M

• Publication status: Published
• Journal: SUPERCONDUCTOR SCIENCE and TECHNOLOGY
• Volume: 7
• Issue: 9
• Pages: 668-671
• Publication date: 1994-09-01
• DOI: 10.1088/0953-2048/7/9/008
• EISSN: 1361-6668
• ISSN: 0953-2048
• Language: English