High Performance YBCO Films
Abstract
High quality YBCO films were successfully deposited on 2.5 cm by 2.5 cm magnesium fluoride substrates. Critical temperatures of 88-89K and transition widths of 0.5K were obtained. Surface quality of Sarnoff-polished magnesium fluoride was improved to a level that produced a Chi-min of about 17% using Rutherford Backscattering. The maximum STO dielectric layer thickness (for capacitor between ground plane and power plane layers) was found to be 2000 angstroms or less in order to allow re-oxygenation of underlying YBCO ground plane. A new bismuth oxide based glass for bonding of the YBCO sample to the metal handle was identified. This glass showed significantly less interaction with silver and better stability at 750K under vacuum than the previously used PbO-based glass. A five micron thick silver layer for the power plane was found sufficient for preventing any reduction of its conductivity due to interaction with the bonding glass during firing. Patterned glass/metal handle attachment to YBCO samples showed good adhesion.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 25, 1994
- Accession Number
- ADA283870
Entities
People
- Aly Fathy
- Barry Thaler
- David Kalokitis
- Edgar J. Denlinger
- K. S. Harshavardhan
- T. Venkatesan
- Valerie Pendrick
Organizations
- Sarnoff Corporation