Umenne Patrice
Department of Electrical and Mining Engineering, University of South Africa, Florida 1709, South Africa.
Micromachines (Basel). 2020 Dec 8;11(12):1088. doi: 10.3390/mi11121088.
The research 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 yttrium barium copper oxide (YBCO) thin film using the femtosecond laser, a spherical convex lens of focal length 30 mm and the G-code control programming language applied to 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 sub-micron sized bridges of width 858 nm, 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.
这项研究源于需要使用飞秒激光制造亚微米和纳米尺寸的桥，以便对约瑟夫森效应进行分析。飞秒激光的脉冲持续时间很短，仅为130飞秒。因此，在光学装置中，人们认为它可以防止超导材料在制造过程中发生热降解。在本文中，使用飞秒激光、焦距为30毫米的球面凸透镜以及应用于平移台的G代码控制编程语言，在超导钇钡铜氧化物（YBCO）薄膜上制造了一系列微米和亚微米尺寸的桥。使用原子力显微镜（AFM）分析了所制造桥的尺寸。结果，制造出了宽度为1.68μm、1.39μm、1.23μm的微米尺寸超导桥以及宽度为858nm、732nm的亚微米尺寸桥。这些桥的长度范围为9.6μm至12.8μm。飞秒激光技术和球面凸透镜可用于制造亚微米尺寸的桥。
