2D-3D type new oxide superconductor devices

我们研究了一种新型的超导器件，命名为2D-3D型氧化物超导晶体管。根据以下实验计划进行研究。(1)射频溅射系统的发展。使用共面二极管的直接和射频溅射系统可能会对超导薄膜造成严重的损伤，如氧脱附，偏离化学计量组成等。这些结构缺陷导致超导性能差。在这项工作中，开发了一种新的系统，使用侧溅射配置。采用侧面溅射多靶射频溅射系统，制备出了（200）取向的Pt薄膜，而不是容易生长的（110）取向。(2)器件为了研制2D-3D型超导器件，需要具有良好取向的二维导电超导薄膜。在这项工作中，Y系统被采用。由于Bi-Sr-Ca-Cu系超导薄膜难以制备，在（100）Pt衬底上制备的YBCO具有c轴取向，Tc高达85 ℃。氧的存在对Pt（100）的取向有很大的影响，形成了Pt-YBCO-Pt三层结构，具有良好的超导性能。三层薄膜的性质显示了2D-3D器件的良好特性。

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.(2) DevicesIn 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.