Deposition of noble metal contacts on YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films

Author

Hahn, R. ; Schaffter, T. ; Klockau, J. ; Fotheringham, G.

Author_Institution

Tech. Univ. Berlin, Germany

Volume

3

Issue

1

fYear

1993

fDate

3/1/1993 12:00:00 AM

Firstpage

2979

Lastpage

2982

Abstract

Ohmic contacts with low specific contact resistivities between YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films and noble metals have been fabricated using ion beam sputter etching and RF-plasma contact preparation. The influence of deposition parameters has been investigated. Specific contact resistivities in the 10/sup -8/ Omega -cm/sup 2/ range at 77 K have been achieved and were evaluated using cross bridge Kelvin test structures with sizes varying between 5 and 50 mu m. The failure rate of wires bonded onto high-temperature superconductor (HTSC)-Au/Ag pads was unacceptable in most cases. Substantial improvements have been achieved with Cr/Ti adhesion sublayers. Deposition parameters for optimum pull test results on MgO and LaAlO/sub 3/ substrates are presented.<>

Keywords

barium compounds; electron beam deposition; high-temperature superconductors; metallisation; ohmic contacts; sputter deposition; sputter etching; superconducting thin films; yttrium compounds; 5 to 50 micron; 77 K; Au-Ag metallisation; Cr-Ti sublayers; Cr/Ti adhesion sublayers; HTSC; LaAlO/sub 3/ substrates; MgO substrates; RF-plasma contact preparation; YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films; cross bridge Kelvin test structures; deposition parameters; failure rate; ion beam sputter etching; low specific contact resistivities; noble metal contacts; ohmic contacts; optimum pull test; Bonding; Bridges; Conductivity; Ion beams; Kelvin; Ohmic contacts; Sputter etching; Sputtering; Testing; Wires;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.234029

Filename

234029