AFM analysis of micron and sub-micron sized bridges fabricated using the femtosecond laser on YBCO thin films.

Abstract

The project arose as a result of the need to use the femtosecond laser to fabricate sub-micron and Nano-sized bridges that could be analyzed for the Josephson effect. The femtosecond laser has a low pulse duration of 130 femtoseconds. Hence in an optical setup it was assumed that it could prevent the thermal degradation of the superconductive material during fabrication. In this paper a series of micron and sub-micron sized bridges where fabricated on superconductive YBCO thin film using the femtosecond laser, a spherical convex lens of focal length 30 mm and the G-code control programming language applied on a translation stage. The dimensions of the bridges fabricated where analyzed using the Atomic Force Microscope (AFM). As a result, micron sized superconductive bridges of width 1.68 μm, 1.39 μm, 1.23 μm and a sub-micron sized bridge of width 732 nm where fabricated. The length of this bridges ranged from 9.6 μm to 12.8 μm. The femtosecond laser technique and the spherical convex lens can be used to fabricate bridges in the sub-micron dimension.