ACED Fab: On-chip CMOS-MEMS Infrared Spectroscopy Systems

金属、气体和许多化学物质的结构都是独特的，在红外光谱波段表现出独特的吸收指纹。使用便携式设备精确检测和跟踪这种光谱具有巨大的潜力，并将使许多应用成为可能，包括实时健康监测、气体检测、光谱学、成像、危险材料的识别等。常见的红外光谱仪依赖于傅立叶变换系统（FTIR），其体积庞大、昂贵、与集成电路不兼容，并且不适合于现实生活中的应用。在这里，基于美国和台湾团队之间的协同合作，将展示一种在室温下运行的片上红外光谱系统，该系统能够使用大量通道从~ 1.5μm到10 μm进行扫描。该系统依赖于在美国制造的小型化和光谱选择性红外传感器阵列和在台湾制造的CMOS芯片的集成，这些芯片实现了最先进的噪声抑制和询问技术。提出的片上红外光谱平台是红外技术领域的重要一步，超越了笨重和昂贵的基于傅立叶变换的光谱仪，成为小型化，负担得起的，大规模生产的设备。这种系统的潜在应用包括传感、通信、成像和光谱学等。在教育方面，该项目将向研究生和本科生提供CMOS技术、红外传感、机械谐振器、超材料以及器件制造和表征等各种科学领域的多学科培训;将研究成果与教育活动相结合，包括将研究内容纳入研究生课程，并通过期刊论文和科学会议广泛传播研究成果;并鼓励妇女和西班牙裔学生参与和保留-PI可以作为榜样-在STEM和研究。除此之外，该计划将促进美国和台湾研究人员之间的合作，并为长期合作伙伴关系和科学互动奠定基础。该项目的目标是展示一种片上红外光谱系统，该系统能够使用大量并行通道从~ 1.5μm到10 μm进行扫描，同时表现出能够超越在室温下运行的竞争技术的性能。为此，将在加州大学戴维斯分校洁净室的单个芯片上制造大型阵列光谱选择性红外传感器，而RF询问和噪声抑制方案将在台湾半导体研究所（TSRI）制造的CMOS芯片上实施。异构集成和打包也将在TSRI进行。关键的组成部分是一个红外探测器，该探测器基于纳米图案化的MEMS和高Q元表面，位于自由空间站立的微机电系统（MEMS）之上，以有效地吸收具有所需光谱分布的光。设计用于实现高机械品质因数并吸收目标波长的每个MEMS将在谐振时由RF信号激发，该RF信号的相位和幅度随着所吸收的红外功率而变化。为了提高系统性能，检测器将包括每个释放腔的两个MEMS，一个用作参考，另一个用作传感器。将I/Q信号用于参考/感测路径，将获得并处理两个单元的相位/幅度变化，以高度抑制共模和环境噪声（电、机械、光学、热）以及电子读出电路噪声和非理想性。除了显著的噪声降低之外，CMOS技术的使用将允许同时询问芯片上的并行传感器的较大阵列，并且将它们的信号多路复用到输出通道。该计划将奠定基础，并展示小型化，超灵敏，低噪音，片上红外光谱系统能够与国家的竞争，这项奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的评估，被认为值得支持。影响审查标准。

Metabolites, gases, and many chemicals are structurally unique and exhibit distinctive absorptive fingerprints in the infrared spectrum band. The accurate detection and tracking of such spectrum using portable devices carry enormous potential and would enable many applications, including real-time health monitoring, gas detection, spectroscopy, imaging, the identification of hazardous materials, etc. Common infrared spectrometers rely on Fourier Transform system (FTIR) that are bulky, expensive, incompatible with integrated circuits, and unsuitable for real-life applications. Here, rooted on a synergetic collaborative effort between U.S. and Taiwan groups, an on-chip infrared spectroscopy system operating at room temperature and able to scan from ~ 1.5μm to 10 μm using a large number of channels will be demonstrated. The system relies on the integration of an array of miniaturized and spectrally-selective infrared sensors fabricated in the US, and CMOS chips fabricated in Taiwan that implement state of the art noise-suppression and interrogation techniques. The proposed on-chip infrared spectroscopy platform constitutes a significant step forward in the field of infrared technologies, moving beyond bulky and expensive Fourier Transform-based spectrometers into miniaturized, affordable, and mass-production ready devices. The potential applications enabled by such systems include sensing, communications, imaging, and spectroscopy, among many others. On the educational front, this project will provide multidisciplinary training to graduate and undergraduate students on a variety of scientific areas such as CMOS technologies, infrared sensing, mechanical resonators, metamaterials, and device fabrication and characterization; integrate research results with education activities, including the incorporation of research content in graduate courses and its broad dissemination through journal papers and scientific conferences; and encourage the participation and retention of women and Hispanic students - the PIs can serve as role model- in STEM and research. Moving beyond, this program will foster the collaboration between US and Taiwan researchers and set the foundations for long-term partnerships and scientific interactions. The goal of this project is to demonstrate an on-chip infrared spectroscopy system able to scan from ~ 1.5μm to 10 μm using a massive number of parallel channels while exhibiting a performance able to surpass competing technologies operating at room temperature. To this purpose, a large array spectrally-selective infrared sensors will be fabricated on a single chip at the UC Davis cleanroom, whereas RF interrogating and noise-suppression schemes will be implemented on a CMOS chip that will be fabricated at the Taiwan Semiconductor Research Institute (TSRI). Heterogeneous integration and packaging will also be carried out at the TSRI. The key building-block is an infrared detector based on nano-patterning ultrathin and high-Q metasurfaces on top of free-space standing microelectromechanical systems (MEMSs) to efficiently absorb light with desired spectral distribution. Each MEMS, designed to achieve a high mechanical quality factor and to absorb targeted wavelengths, will be excited at resonance by a RF signal whose phase and amplitude changes with the absorbed infrared power. To enhance the system performance, the detector will include two MEMS per released cavity, one serving as the reference and the other as the sensor. Exploiting I/Q signals for reference/sensing paths, the phase/amplitude variations of both units will be obtained and processed to highly suppress common mode and environmental noises (electrical, mechanical, optical, thermal) as well as the electronic readout circuit noises and non-idealities. In addition to significant noise reduction, the use of CMOS technology will permit to interrogate simultaneously a larger array of parallel sensors on a chip, and to multiplex their signals towards an output channel. This program will lay the foundational groundwork and demonstrate miniaturized, ultra-sensitive, low-noise, on-chip IR spectroscopy systems able to compete with state-of-the-art FTIR technologies operating at room temperature while strengthening the partnership and scientific interactions between USA and Taiwan.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.