Three-dimensional nano-machining in high-Tc oxide superconductor whiskers and thin films

Abstract

Three-dimensional nano/micro-machining (3D machining) is a versatile technique to fabricate devices in scale to quantum level. Three-dimensional focused ion beam (3D-FIB) etching technique is one of the most promising mask-less 3D-machining techniques which give freedom of milling through whisker or thin films and help to fabricate tunnel junction devices. In this chapter, the base materials of these devices are high- Tc superconductor whiskers and thin films. Particularly, this chapter explains the fabrication process of Josephson junction stack devices of high-Tc superconductor Bi2Sr2CaCu2O8+δ single-crystal whiskers and multilayered YBa2Cu3O7/PrBa2Cu3O7thin films. With 3D-FIB etching technique, it is possible to mill down to nano- and submicron scale. The smallest in-plane area of about 0.16 μm 2 is discussed in this chapter.