基于单个宽频CMOS探测器的太赫兹焦平面扫描成像系统  

Focal plane scanning imaging system based on single broadband CMOS terahertz detector

作　　者：林越 张辉[1] 祁峰 刘朝阳[2,3,4] LIN Yue;ZHANG Hui;QI Feng;LIU Zhaoyang(School of Electrical and Control Engineering,Shenyang Jianzhu University,Shenyang 110168,China;Key Laboratory of Opto-Electronic Information Processing,Chinese Academy of Sciences,Shenyang 110169,China;Shenyang Institute of Automation,Chinese Academy of Sciences,Shenyang 110169,China;Key Laboratory of Terahertz Imaging and Sensing,Liaoning Province,Shenyang 110169,China)

机构地区：[1]沈阳建筑大学电气与控制工程学院,沈阳110168 [2]中国科学院光电信息处理重点实验室,沈阳110169 [3]中国科学院沈阳自动化研究所,沈阳110169 [4]辽宁省太赫兹成像与传感重点实验室,沈阳110169

出　　处：《集成电路与嵌入式系统》2024年第5期35-41,共7页INTEGRATED CIRCUITS AND EMBEDDED SYSTEMS

基　　金：雄安新区科技创新专项(2022XAGG0181);国家自然科学基金项目(61804160、61801467);辽宁省自然科学基金项目(2022 MS 034)。

摘　　要：太赫兹波是介于毫米波与红外光之间的电磁波,具有强穿透性、非电离性、高瞬时带宽等特点,在安全检查、无损检测、医疗成像等领域有着广阔的应用前景。在成像系统中,探测器是至关重要的部分。本文提出了一种将不同中心频率的窄带探测器输出结合实现宽频带探测的结构,为了减少面积,这些窄带探测器采用嵌套式结构,即高频窄带探测器被依次放置在低频窄带探测器的内部,每一个窄带探测器均包括环形天线、匹配网络和场效应晶体管检波电路。该探测器由65 nm标准CMOS工艺制成,探测频率范围覆盖了100~1000 GHz。基于该宽频探测器搭建实现了太赫兹焦平面成像系统,该系统主要包括太赫兹辐射源、聚四氟乙烯(PTFE)透镜、宽频CMOS探测器等。实验结果表明,该成像系统在100 GHz、220 GHz和300 GHz频率下能够稳定成像,并且随着频率的提高,成像质量也明显提升。通过对得到的成像结果使用形态学闭运算进行优化,解决了成像中信息缺失的问题,有效地改善了成像质量。Terahertz wave is an electromagnetic wave between millimeter wave and infrared light,which has many feature like strong penetration capability,non-ionization and high instantaneous bandwidth.For these qualities,terahertz waves have a wide range of potential applications in non-destructive testing,medical imaging,safety inspection,and other areas.In the imaging system,the detector is an essential part.This paper presents a structure that combines the output of narrow-band detectors with different center frequencies to realize wide-band detection.In order to reduce the area,these narrowband detectors adopt a nested structure,which means that the high-frequency narrowband detectors are placed inside the low-frequency narrowband detectors in turn.Each narrow-band detector includes a loop antenna,a matching network and a field effect transistor(FET)detector circuit.The detector is fabricated in a 65 nm standard CMOS process,and the detection frequency range covers 100 GHz to 1000 GHz.Based on this broadband detector,we propose a terahertz focal plane imaging system,which mainly consists of a terahertz radiation source,a PTFE lens,a broadband CMOS detector,etc.The measurement results have shown that the focal plane imaging system is capable of stably imaging at frequencies of 100 GHz,220 GHz and 300 GHz.The imaging quality improves significantly with increasing frequency.In order to solve the problem of missing information in measurement images,the morphological closing algorithm is used to process the original image.This algorithm effectively fills in the missing information and enhances the quality of the image.

关 键 词：太赫兹成像 宽带CMOS探测器 焦平面成像 闭运算 窄带探测器 

分 类 号：TN42[电子电信—微电子学与固体电子学]