Characteristics of Superconducting Nb Layer Fabricated Using High-Vacuum Electron Beam Evaporation
Year: 2001
Type: article
Abstract: We have fabricated a niobium (Nb) layer for a Josephson junction by means of a high-vacuum electron beam (EB) evaporation technique. The high-vacuum EB-evaporated Nb layer is deposited under the base pressure of 4×10-9 Pa and the deposition rate of 1.2 nm/min. In spite of the extremely low deposition rate, Nb layers of over 50 nm thickness have the transition temperature of 9.3 K and the ratio of residual resistivity of more than 3. The surface roughness and the grain size of the high-vacuum EB-evaporated Nb layer are studied using atomic force microscopy and X-ray diffraction analysis. The stress in the high-vacuum EB-evaporated Nb layers is examined by measuring the change in the radius of curvature of the substrate before and after Nb layer deposition, and the X-ray diffraction patterns of the Nb layers. The high-vacuum EB-evaporated Nb layer exhibits a weak tensile stress.
DOI: 10.1143/jjap.40.576
Authors: Shin'ichi Morohashi, Norihisa Takeda, Shogo Tsujimura, Masanori Kawanishi, Keita Harada, Shoji Maekawa, Noriaki Nakayama, Takashi Noguchi
Institutions: Yamaguchi University, Nobeyama Radio Observatory
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2000924555