Technology of fabrication superconducting free-standing structures (FSS)

TL;DR

This paper presents a novel fabrication method for superconducting microstructures that are suspended from substrates, exploring two configurations and analyzing their effects on superconducting properties and thermal dissipation.

Contribution

It introduces two new suspended microstructure configurations and investigates their fabrication process and impact on superconducting characteristics and thermal behavior.

Findings

Suspended micro-structures cause a 10-15% reduction in superconducting parameters.

Thermal coupling significantly influences energy dissipation, varying by up to 250 times.

Gas-phase etching effectively creates isolated superconducting microstructures.

Abstract

In this study, a method for fabrication of superconducting microstructures that are partially or completely isolated from the substrate has been proposed. Two configurations of suspended microbridges have been suggested, i. e., the first structure that features a T-shaped etching of the substrate and the second structure which is completely separated from the substrate through periodically positioned supports. The creation of suspended structures is based on the principle of gas-phase etching of amorphous silicon oxide in a mixture of hydrogen fluoride (HF) and ethanol gases. In the course of the experiments, it has been discovered that suspending micro-structures in the configuration of a micro-bridge results in a slight reduction in superconducting characteristics, ranging from 10 to 15% of the initial parameters. It has also been demonstrated that the thermal coupling between the film and the substrate significantly affects the dissipation of thermal energy. The power dissipated into the substrate at room temperature can vary by up to 250 times based on the value of the micro-bridge undercutting.