Method for optimizing superconducting performance of niobium nitride film on silicon substrate by using buffer layer

Abstract

The invention discloses a method for optimizing the superconducting performance of a niobium nitride film on a silicon substrate by using a buffer layer, comprising the following steps of: performing magnetron sputtering of a six nitrogen five niobium film on a high-resistance silicon substrate to serve as a buffer layer, and performing in-situ magnetron sputtering of a niobium nitride film in a vacuum chamber. According to the method, the six nitrogen five niobium film buffer layer is coated on the high-resistance silicon substrate through magnetron sputtering so that the superconducting performance of the niobium nitride film is obviously improved, and particularly, the performance of an ultra-thin film is more obviously improved. The method disclosed by the invention can also be expanded to improve the superconducting performance of the niobium nitride film on other substrates and is simple, easy and obvious in effect.

Description

technical field [0001] The invention relates to the field of preparing superconducting niobium nitride thin films, in particular to a method for optimizing the superconducting properties of niobium nitride thin films on silicon substrates by using a buffer layer. Background technique [0002] Niobium nitride thin film is a superconducting thin film with excellent performance. It has an irreplaceable position in the fields of quantum communication and terahertz detection. devices such as single-photon detectors. The niobium nitride films currently used are mainly prepared on two substrates of magnesium oxide and high-resistance silicon. The lattice mismatch between the magnesium oxide substrate and niobium nitride is small, so epitaxial niobium nitride films can be grown, superconducting The performance is excellent, but the magnesium oxide substrate is easy to hydrolyze, and the niobium nitride thin film prepared on it and the device based on it are limited in service life ...

AI Technical Summary

Problems solved by technology

The niobium nitride films currently used are mainly prepared on two substrates of magnesium oxide and high-resistance silicon. The lattice mismatch between the magnesium oxide substrate and niobium nitride is small, so epitaxial niobium nitride films can be grown, superconducting Excellent performance, but the magnesium oxide substrate is easy to hydrolyze, and the niobium nitride film prepared on it and the devices based on it are limited in service life and stability

Niobium nitride thin films prepared on high-resistance silicon substrates have advantages in subsequent processing (such as further preparation of resonant cavities to improve chip performance) and integration with silicon processes. However, due to the large lattice mismatch, the thin films have multiple Crystalline properties, resulting in a greater reduction in superconducting properties

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