|Budget Amount *help
¥3,500,000 (Direct Cost : ¥3,500,000)
Fiscal Year 1999 : ¥700,000 (Direct Cost : ¥700,000)
Fiscal Year 1998 : ¥2,800,000 (Direct Cost : ¥2,800,000)
We have investigated a new type of superconductor devices, named as 2D-3D type oxide super conducting transistor. The investigation was carried out according to following experimental plans.
(1) Development of an RF sputtering system.
Usual an RF sputtering systems using co-planar diodes are likely to give severe damages on the super conducting then films, such as an oxygen desorption, deviation from the stoichiometric composition, etc. These structural defects results in poor super conducting properties.
In this work, a new system using side-sputtering configuration was developed. This system could diminish the attack of ionized oxygen atoms.
By using the side-sputter multi-target an RF sputtering system, we have prepared Pt thin films with a single orientation of (200), instead of (110) orientation easy to grow up.
In order to develop the 2D-3D type super conductor device, well-oriented two dimensionally conducting super conducting thin films are required. In this work, Y system was adopted. Instead of Bi-system, because of the difficulty to get the super conducting Bi-Sr-Ca-Cu thin films.
It was found that the YBCO deposited on the (100) Pt have a c-axis orientation and a high Tc of 85Κ. The orientation of Pt (100) was strongly affected by the presence of oxygen during deposition.
The tri-layer structure, Pt-YBCO-Pt was developed and showed good super conducting properties. The property of the tri-layer film showed a promising characteristic of 2D-3D devices.