Ultrahigh-reflective optical thin films prepared by reactive magnetron sputtering with RF-induced substrate bias

Tung-Hsun Chung; Xiao-Lu Zou; Qi-Hang Zhang; Meng Wang; Xian-Qing Zhu; Ming-Xuan Zhang; Qian-Cheng Lin; Rong Liao; Xing-Yang Cui; Jun Zhang; Ping Xu; Han-Ning Dai; Yu-Ao Chen; Yong-Heng Huo; Jian-Wei Pan

doi:10.1063/5.0169714

Ultrahigh-reflective optical thin films prepared by reactive magnetron sputtering with RF-induced substrate bias

Rev Sci Instrum. 2024 Apr 1;95(4):045107. doi: 10.1063/5.0169714.

Authors

Tung-Hsun Chung^{1

2

3}, Xiao-Lu Zou^{1

2

3}, Qi-Hang Zhang^{1

2}, Meng Wang^{1

2}, Xian-Qing Zhu^{1

2

3}, Ming-Xuan Zhang², Qian-Cheng Lin^{1

3}, Rong Liao^{1

3}, Xing-Yang Cui^{2

3}, Jun Zhang², Ping Xu^{1

2

3}, Han-Ning Dai^{1

2

3}, Yu-Ao Chen^{1

2

3}, Yong-Heng Huo^{1

2

3}, Jian-Wei Pan^{1

2

3}

Affiliations

¹ Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China.
² Shanghai Research Center for Quantum Science and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Shanghai 201315, China.
³ Hefei National Laboratory, University of Science and Technology of China, Hefei 230088, China.

PMID: 38564326
DOI: 10.1063/5.0169714

Abstract

Optical thin films with high-reflectivity (HR) are essential for applications in quantum precision measurements. In this work, we propose a coating technique based on reactive magnetron sputtering with RF-induced substrate bias to fabricate HR-optical thin films. First, atomically flat SiO2 and Ta2O5 layers have been demonstrated due to the assistance of radio-frequency plasma during the coating process. Second, a distributed Bragg reflector (DBR) mirror with an HR of ∼99.999 328% centered at 1397 nm has been realized. The DBR structure is air-H{LH}19-substrate, in which the L and H denote a single layer of SiO2 with a thickness of 237.8 nm and a single layer of Ta2O5 with a thickness of 171.6 nm, respectively. This novel coating method would facilitate the development of HR reflectors and promote their wide applications in precision measurements.