Multipixel single-photon avalanche diode array for parallel photon counting applications
Multipixel single-photon avalanche diode array for parallel photon counting applications
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DOI：
10.1080/09500340802318309
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发表时间：
2009-01-01
影响因子：
1.3
通讯作者：
Cova, Sergio
中科院分区：
文献类型：
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作者：
Rech, Ivan;Marangoni, Stefano;Cova, Sergio
在生命科学中，用于表征生物过程的光学技术已经成熟并广泛使用。在大多数情况下，为了获得最佳性能，需要具有单光子探测能力的探测器。此外，对此类信息不断增长的需求正在推动该技术走向分析的并行化。这些要求使得开发新的检测头变得非常具有挑战性，因为最先进的检测器，例如光电倍增管 (PMT) 和电荷耦合器件 (CCD)，有一些缺点。例如，在荧光相关光谱 (FCS) 中，必须在短时间内监测荧光波动，因为典型的时间常数范围从数百纳秒到毫秒。在这种情况下，为此应用开发并行模块非常具有挑战性。事实上，PMT 体积庞大且无法集成，而 CCD 和电子倍增 CCD 等成像检测器的使用则受到读取时间的强烈限制，而读取时间决定了 FCS 分析可检测到的最小相关时间。我们在此提出了一种多通道光子计数模块，该模块利用单光子雪崩二极管 (SPAD) 的单片阵列。探测器阵列由8个直径50 m的SPAD组成，具有低暗计数率和高光子探测效率（550 nm处50%）；像素间串扰概率低至2×10-3。使用高度集成的有源猝灭电路可以设计非常紧凑的读出电路，同时提供八个完全独立的计数通道，以高计数率（每秒高达 3000 万次计数）运行。并行模式操作、高计数率和低成本使该模块成为 FCS 分析广泛推广的潜在突破。
In life science, optical techniques for the characterization of biological processes are well established and widely used. In most of them, to obtain the best performances, detectors with single-photon detection capability are required. Moreover, the growing demand for this type of information is pushing the technology towards a parallelization of the analysis. These requirements make it very challenging to develop new detection heads, because state-of-the-art detectors, such as photomultiplier tubes (PMTs) and charged coupled devices (CCDs), have some drawbacks. For example, in fluorescence correlation spectroscopy (FCS) fluorescence fluctuations must be monitored on a short time scale because typical time constants range from hundreds of nanoseconds to milliseconds. In this case, developing parallel modules for this application is very challenging. In fact, PMTs are bulky and they cannot be integrated, while the use of imaging detectors, such as CCDs and electron multiplying CCDs, is strongly limited by the read time that determines the minimum correlation time detectable by FCS analysis. We present here a multichannel photon counting module that exploits a monolithic array of single-photon avalanche diodes (SPADs). The detector array consists of eight 50 m diameter SPADs featuring low dark counting rate and high photon detection efficiency (50% at 550 nm); inter-pixel crosstalk probability is as low as 2 10-3. The use of highly integrated active quenching circuits makes it possible to design a very compact read-out circuit, yet providing eight fully independent counting channels operating at high count rate (up to 30 million counts per second). Parallel-mode operation, high count rate and low-cost make this module a potential breakthrough for a widespread diffusion of FCS analysis.