Silver-assisted growth of NdBa2Cu3O7-d thin films: A novel approach for the growth of superior quality ceramic oxide films

TL;DR

This paper introduces a novel molecular beam epitaxy method using silver flux and RF-activated oxygen to grow high-quality NdBa2Cu3O7-d thin films that are free of silver but benefit from its growth-enhancing effects.

Contribution

The study presents a new silver-assisted growth technique that improves film quality while ensuring the final film contains no silver, suitable for high-frequency applications.

Findings

30% increase in critical current density

Films are free of silver despite silver-assisted growth

Method applicable to other complex oxides

Abstract

We have grown NdBa2Cu3O7-d films under silver atomic flux by molecular beam epitaxy, which show a drastic improvement in microstructure and also crystallinity leading to 30 % enhancement in critical current density. The most remarkable point is that the final film is free from silver. The key to our process in achieving a silver-free film was the use of RF-activated oxygen that oxidizes silver, nonvolatile, to silver oxide, volatile at the deposition temperature. This process enables one to utilize the beneficial effects of silver in the growth of oxide films and at the same time ensures that the final film be free from silver, which is important for high-frequency applications. This method can be made use in the growth of thin films of other complex oxide materials.