USTC realizes national production of single-photon detector chips

The InGaAs single-photon detector chip designed and fabricated by Prof. Wang Liang's research group from the Department of Optics and Optical Engineering, University of Science and Technology of China has made great progress. The research team optimized the optical performance of the single-photon detector chip by designing a metal-distributed Bragg reflector, completed the fully autonomous design and fabrication of the single-photon detector chip with low intrinsic dark count, and realized the development of the single-photon detector chip. Nationalization has taken an important step towards solving the cutting-edge scientific and technological problems urgently needed by the country. The related research results were published online in the Journal of Lightwave Technology, a well-known journal in the field of electronic engineering technology, titled "High performance InGaAs/InP single-photon avalanche diode using DBR-metal reflector and backside micro-lens".

Semiconductor single-photon avalanche diodes (SPADs) based on InGaAs materials have excellent characteristics such as high sensitivity at the single-photon level, eye safety in the short-wave infrared band, low loss in the atmospheric window band, penetrating haze, low power consumption, small size, and easy integration. . These advantages make SPAD play a huge role in quantum information technology, active and passive focal plane detectors, urban mapping, lidar and other fields, and have great civil, commercial and military value.

Professor Wang Liang's research team achieved epitaxial structure growth with low defect density and high doping accuracy by adjusting the growth parameters such as MOCVD temperature, V/III ratio, and doping concentration. Based on the structure of the SPAD device, a new type of broad-spectrum (all-optical communication band) total reflection mirror, that is, a metal-distributed Bragg mirror, is proposed and designed to improve the photoelectric absorption efficiency of the SPAD chip. The low dark count SPAD with a 12 μm window prepared by the research team has an ultra-low intrinsic dark count of 127 Hz at a temperature of 233 K and a detection efficiency of 10%, which is an order of magnitude lower than similar foreign products and has better device performance. , this chip can meet the needs of single-photon detection in applications such as quantum communication and can replace imported devices.

Figure 1 (a) Schematic diagram of the device structure of SPAD (b) 12μm window ultra-low dark count SPAD chip and test results

Professor Wang Liang from the Department of Optics and Optical Engineering of the University of Science and Technology of China is the corresponding author of the paper, and doctoral student Zhang Bojian is the first author of the paper. This research was funded by the Ministry of Science and Technology of China, the National Natural Science Foundation of China and the Anhui Provincial Department of Science and Technology, as well as the School of Physics, China University of Science and Technology, the 13th Research Institute of China Electronics Technology Group, China University of Science and Technology Micro and Nano Research and Manufacturing Center, and the Chinese Academy of Sciences Quantum Information Key Laboratory Support.

Paper link:

https://ieeexplore.ieee.org/abstract/document/9720212