Design and characterization of a package-less hybrid PDMS-CMOS-FR4 contact-imaging system for microfluidic integration.
Design and characterization of a package-less hybrid PDMS-CMOS-FR4 contact-imaging system for microfluidic integration.
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用于微流体集成的无封装混合 PDMS-CMOS-FR4 接触成像系统的设计和表征。
DOI：
10.1117/1.jmm.17.3.034501
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
WoodChiang,Shiuh-Hua
中科院分区：
文献类型：
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作者：
Galan,Andres;Nordin,GregoryP;WoodChiang,Shiuh-Hua
我们展示了一种混合的“无封装”聚二甲基硅氧烷（PDMS）-互补金属氧化物半导体（CMOS）-FR 4接触成像系统。该系统将CMOS图像传感器直接嵌入PDMS层而不是标准芯片封装中，以支持比现有技术中的微流体结构大得多且更复杂的微流体结构。CMOS/PDMS层是自对准的，以形成连续的平坦表面，从而为上部微流体层提供结构支撑。该系统由五层PDMS组成，实现了流体通道、阀门、腔室和入口/出口。带有集成信号调节电路的定制CMOS图像传感器直接捕获样品流体中的光，实现高光学收集效率。由于集成过程提供的灵活性，该系统首次展示了接触成像中的集成阀。此外，我们提出了第一个直接比较的CMOS图像传感器和光电倍增管（PMT）在相同的接触成像条件下的光学性能。测量结果表明，我们的CMOS传感器实现了17 dB更好的信噪比（SNR）相比，商业PMT在广泛的集成时间范围内，最大信噪比为47 dB。化学发光测试成功地显示了不同分析物浓度和积分时间的信号检测。接触式成像系统证明了9，10-二苯基蒽基溶液的检测限为25μM。
We demonstrate a hybrid “package-less” polydimethylsiloxane (PDMS)–complementary metal–oxide–semiconductor (CMOS)-FR4 system for contact imaging. The system embeds the CMOS image sensor directly in a PDMS layer instead of the standard chip package to support microfluidic structures much larger and more complex than those in prior art. The CMOS/PDMS layer is self-aligned to form a continuous, flat surface to provide structural support for upper microfluidic layers. The system consists of five layers of PDMS implementing fluid channels, valves, chambers, and inlets/outlets. A custom CMOS image sensor with integrated signal conditioning circuits directly captures light from sample fluid for high optical collection efficiency. Owing to the flexibility afforded by the integration process, the system demonstrates, for the first time, integrated valves in contact imaging. Moreover, we present the first direct comparison of the optical performance of a CMOS image sensor and a photomultiplier tube (PMT) in identical contact-imaging conditions. Measurements show that our CMOS sensor achieves 17 dB better signal-to-noise ratio (SNR) compared with a commercial PMT across a broad range of integration times, with a maximum SNR of 47 dB. Chemiluminescent testing successfully shows signal detection for different analyte concentrations and integration times. The contact-imaging system demonstrates a detection limit of 25μM of a 9,10-diphenylanthracene-based solution.