斜坡式超導穿隧元件之製作與特性研究

Fabrication and Characteristics of Ramp-type Superconducting Tunneling Device

曾上銘(Shang-Ming Tseng)

指導教授 ： 王立民

國立臺灣大學/理學院/物理研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.01358

摘要

本研究探討了一種斜坡式結構約瑟夫森元件的製作，利用超導體釹鋇銅氧(NdBa2Cu3O7-δ)及絕緣層鈦酸鍶(SrTiO¬3)成長於鈦酸鍶基板上。以光學微影及離子蝕刻方式製作斜坡，利用射頻磁控濺鍍方式成長所需之薄膜。利用X-Ray及MPMS做薄膜特性的量測；原子力顯微鏡做斜坡表面形態之量測。
由測量結果得知，以濺鍍方式可得到品質良好之超導薄膜，以乾蝕刻之方式可做出坡度平整、表面平緩之斜坡，為一可能取代雙晶基板製作約瑟夫森結之替代方案。

關鍵字

高溫超導 ； 約瑟夫森結 ； 釹鋇銅氧 ； 量子穿隧元件

並列摘要

A ramp-type technique for the fabrication of high temperature superconducting tunneling device is researched. We use NdBa2Cu3O7-δ as top and bottom superconducting layer; SrTiO3 as insulating and barrier layer, both grown on 1cm2 SrTiO¬3 substrate.
The crystalline orientation and surface morphology are characterized by X-ray diffraction and atomic force microscope. The electric and magnetic properties of the superconducting films are studied by using low temperature measurement and superconducting quantum interference device (SQUID)
We found a gentle ramp angle and a flat ramp surface can be fabricated using dry-etching technique, combined with high quality c-axis orientation superconducting films, this method can be an alternative to produce artificial boundary josephson junctions.

並列關鍵字

ramp-type structure ； josephson junction ； NBCO ； SQUID

參考文獻

[7] C.C. Tsuei, and J. R. Kirley, Rev. Mod. Phys.,72, 969(2000)

[22] Pauza A J, Moore D F, Campbell A M et al. IEEE Trans. Appl Supercond.,1995,5:3410

[23] Liang W Y, Yuanh J, Yan Y et al. Mater, Sci. Eng. B, 1996, 41. 5

[25] Dimos D, Chaudhari P, Mannhart J et al. Phys. Rev. Lett.,1988, 61:219

[28] Simon R W, Bulman J B, Burch J F et al. IEEE Trans. Magn., 1991, 27:3209