基于超薄钽酸锂晶片及炭黑红外吸收层的热释电探测器  

Pyroelectric Detector Based on Ultra-Thin LiTaO_3 Wafer and Carbon Black Infrared Coating

作　　者：赵玲[1] 赵燕[1] 何秀丽[1] 贾建[1] 高晓光[1] 李建平[1] 

机构地区：[1]中国科学院电子学研究所传感技术国家重点实验室,北京100190

出　　处：《纳米技术与精密工程》2014年第1期44-50,共7页Nanotechnology and Precision Engineering

基　　金：国家高技术研究发展计划(863计划)资助项目(2009AA04Z328);国家自然科学基金资助项目(60871055)

摘　　要：基于钽酸锂（LiTaO3）的热释电探测器具有灵敏度高、热释电系数大、响应范围宽等优点而被广泛应用于非分光红外气体检测．在nTaO3，热释电探测器制备过程中，采用预置沟槽方法制备出约20μm厚的超薄LiTaO3晶片，该方法既能控制晶片厚度又能实现自动解片，简化了探测器制备工艺；采用电喷雾方法制备出炭黑红外吸收层，该方法工艺简便，制备的吸收层分布均匀，结构疏松．电喷雾时间为20rain时制备的吸收层在常用气体吸收波段（2．5～10μm）的红外吸收率达98％以上，使探测器信号幅值提高了约2．6倍．热释电探测器性能测试结果表明：单元结构探测器的黑体探测率可达1．78×10。cm·Hz1/2。／W；二元补偿结构探测器信噪比为单元器件的2倍；将二元补偿结构探测器应用于非分光红外气体测试系统，进行了SO2气体检测，等噪声检测下限约为1×10^-6．Pyroelectric detectors based on LiTaO3 wafer are widely used for gas detection due to their merits of high sensitivity, high pyroelectric coefficient and wideband sensing. A convenient method of groove presetting was proposed to control the thickness of the wafer and split the wafer automatically dur- ing the process of mechanical lapping and polishing and the ultra-thin LiTaO3 wafer with the thickness of about 20 μm was obtained. The electrospray technique was introduced to fabricate carbon black infrared coating for the detectors. The coating shows uniform and porous microstructure and has the absorbance more than 98% at the common gas absorption wavelength （2.5--10 μm）when the optimized electrospray time is about 20 rain. By using the black coating, the voltage response of the detector was increased by about 2.6 times. Three voltage mode pyroelectric detectors including single-element detector, dual-ele- ment detector with compensation and four-element detector with compensation and reference channel were investigated. The specific detectivity of the single-element detector is 1.78 x 108 cm Hzl/2/W. The sig- nal-to-noise ratio of the detector with compensation is doubled compared to the single-element detector. The pyroelectric detector with compensation was used in a non-dispersive infra-red （NDIR） gas detection system. The testing result of SO2 gas indicates that the detection limit is about 1 x 10 -6.

关 键 词：热释电 钽酸锂 炭黑红外吸收层 气体检测 

分 类 号：TN215[电子电信—物理电子学]