Distinguishing the impact of oxidation on the Josephson junction oxide barrier through the 1/f behavior

Abstract

The quality of the oxide barrier in Josephson junctions (JJs) is crucial for devices with it as the core structure. Despite the critical nature of the oxidation process in JJ fabrication, there remains a lack of systematic research on its impact. Our study aims to fill this gap by comprehensively investigating the influence of oxidation parameters and methods on the oxide barrier quality. To achieve this, we evaluate the low-frequency 1/f noise of JJs produced using various fabrication processes. Our findings demonstrate that a weak oxidation strength (oxygen pressure × exposure time) and a dynamic oxidation method contribute positively to the formation of high-quality oxide barriers. This research provides an important reference for optimizing the oxidation process.