학술논문

Investigation of Superconducting Ti/Ti-Au/Au Tri-Layer Films With a Co-Sputtering Process for Transition-Edge Sensors
Document Type
Periodical
Source
IEEE Transactions on Applied Superconductivity IEEE Trans. Appl. Supercond. Applied Superconductivity, IEEE Transactions on. 33(5):1-5 Aug, 2023
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Films
Gold
Conductivity
Sputtering
Atomic layer deposition
Substrates
Uncertainty
Artificial diffusion
co-sputtering
proximity effect
superconductivity
Ti/Au
transition-edge sensor
Language
ISSN
1051-8223
1558-2515
2378-7074
Abstract
The critical temperature ( T c ) of superconducting Ti/Au bilayer films is crucial for the performance of transition-edge sensors. We use a co-sputtering technique to insert a Ti-Au mixture layer as an artificial diffusion layer between a superconducting Ti film and a normal Au bilayer. The Ti-Au mixture layers have different thicknesses and component ratios. The cross-section and element information of thin films was characterized by a high-resolution transmission electron microscopy (HRTEM) and energy dispersive X-ray spectroscopy (EDS). The variation of T c is measured for a series of Ti/Ti-Au/Au films. T c is related to both the thickness and Ti-Au ratio in the mixture layer. We attempt to model the T c variation based on the Usadel theory with an equivalent thickness ratio.