Tan-based Josephson junction and preparation method thereof

Abstract

The invention provides a TaN-based Josephson junction and a preparation method thereof. The preparation method includes: providing a substrate, forming an NbN bottom layer film, a metal TaN barrier layer, and an NbN top layer film, etching to define a bottom electrode and a junction region, and forming an isolation layers and wiring layers. The invention forms a metal TaN barrier layer through an ion nitriding process to obtain a Josephson junction of SNS structure, which can improve the stability of the resistivity of the barrier layer without parallel resistors, and solves the problems of SIS Josephson junction magnetic flux noise and integration , improve the repeatability and stability of the process, the resistivity and thickness of the barrier layer material can be freely adjusted by parameters such as ion nitriding time and power, effectively avoiding the formation of an insulating layer at the S / N interface, and the surface smoothness is high And the nitriding uniformity is good, which improves the characteristic voltage I of the SNS junction c R n Small defects that limit the high-frequency application of devices are conducive to the development of high-quality NbN SNS Josephson junctions.

Description

technical field [0001] The invention belongs to the field of superconducting electronics, in particular to a TaN-based Josephson junction and a preparation method thereof. Background technique [0002] Human beings have never stopped pursuing high-performance computing systems since they entered the information age. After more than half a century of rapid development of digital circuits based on semiconductor transistors, the integration of transistors is approaching the physical limit size, Moore's Law is about to fail, and digital computing has encountered bottlenecks in energy consumption and speed. A superconducting single flux quantum (SFQ, Single Flux Quantum) circuit uses a superconducting Josephson junction as a switch to represent logic information by whether there is a single flux quantum in a superconducting loop. Compared with the high and low level encoding method of traditional semiconductor CMOS circuits, superconducting SFQ circuits have quantized signal acc...

AI Technical Summary

Problems solved by technology

However, the Josephson junction of the current SNS structure is difficult to realize the free regulation of the physical properties of the barrier layer under the premise of ensuring the stability of the barrier layer resistivity, and to ensure the uniformity of the film in a large size range to achieve a high characteristic voltage SNS Josephson junction. knot preparation

Images