近日，Artilux公司的Neil Na及其研究团队取得一项新进展。经过不懈努力，他们实现锗硅单光子雪崩二极管的室温下工作。相关研究成果已于2024年2月21日在国际权威学术期刊《自然》上发表。

该研究团队报道了一种在室温下工作的CMOS兼容的高性能锗硅SPAD，其噪声等效功率比以前基于锗的SPAD提高了2-3.5个数量级。暗计数率、1310 nm处的单光子探测概率、时序抖动、后脉冲特征时间和后脉冲概率等关键参数分别为19kHzμm^-2、12%、188ps、~90ns和<1%，击穿电压低至10.26V，过量偏压小至0.75V。研究人员三维点云图像捕获与直接飞行时间技术作为概念验证。这项研究工作为在日常生活中使用单光子灵敏SWIR传感器、成像仪和光子集成电路铺平了道路。

据悉，探测单光子的能力导致了许多研究领域的进步。虽然已经开发了各种类型的单光子探测器，但由于两个主要因素，即(1)需要在低温下工作，(2)与互补金属氧化物半导体(CMOS)制造工艺不兼容，到目前为止，据我们所知，只有硅基单光子雪崩二极管(SPAD)获得了主流成功，并已用于消费电子产品。随着将工作波长从近红外转移到短波红外(SWIR)的需求越来越多，以获得更好的安全性和性能，需要一种替代解决方案，因为硅对波长超过1μm的光吸收可以忽略不计。

附：英文原文

Title: Room temperature operation of germanium–silicon single-photon avalanche diode

Author: Na, Neil, Lu, Yen-Cheng, Liu, Yu-Hsuan, Chen, Po-Wei, Lai, Ying-Chen, Lin, You-Ru, Lin, Chung-Chih, Shia, Tim, Cheng, Chih-Hao, Chen, Shu-Lu

Issue&Volume: 2024-02-21

Abstract: The ability to detect single photons has led to the advancement of numerous research fields. Although various types of single-photon detector have been developed, because of two main factors—that is, (1) the need for operating at cryogenic temperature and (2) the incompatibility with complementary metal–oxide–semiconductor (CMOS) fabrication processes—so far, to our knowledge, only Si-based single-photon avalanche diode (SPAD) has gained mainstream success and has been used in consumer electronics. With the growing demand to shift the operation wavelength from near-infrared to short-wavelength infrared (SWIR) for better safety and performance, an alternative solution is required because Si has negligible optical absorption for wavelengths beyond 1μm. Here we report a CMOS-compatible, high-performing germanium–silicon SPAD operated at room temperature, featuring a noise-equivalent power improvement over the previous Ge-based SPADs by 2–3.5 orders of magnitude. Key parameters such as dark count rate, single-photon detection probability at 1,310nm, timing jitter, after-pulsing characteristic time and after-pulsing probability are, respectively, measured as 19kHzμm^-2, 12%, 188ps, ~90ns and <1%, with a low breakdown voltage of 10.26V and a small excess bias of 0.75V. Three-dimensional point-cloud images are captured with direct time-of-flight technique as proof of concept. This work paves the way towards using single-photon-sensitive SWIR sensors, imagers and photonic integrated circuits in everyday life.

DOI: 10.1038/s41586-024-07076-x

Source: https://www.nature.com/articles/s41586-024-07076-x