基于钽酸锂晶体薄片的红外探测器设计及应用

通过减薄、键合、抛光等技术加工成厚度达到10μm左右的超薄晶片,然后通过蒸金、黑化等处理技术将其制备成红外敏感元件.根据红外光谱吸收原理,为提高分辨率和选择性吸收性能,在敏感元件前段集成了窄带滤光片.制备的敏感元件与选用的窄带滤光片,以及CMOS放大器与电阻和电容各一个都被封装和集成在一个TO-18型管壳内,最终被设计加工成为单一通道的红外探测器,其滤光片可根据要求的波带范围进行更换.利用两个吸收波长分别为(3 310±90)nm和(3 910±60)nm的单元探测器,设计并制作了一个微型气体传感器.该气体传感器能实现检测一些烃类气体,文中对乙烯气体进行了实验测试,并进行了实验数据分析.分析结果表明:这种气体传感器具备较好的检测气体浓度的能力,能检测的最大量程为30 000×10-6,达到分辨100×10-6的检测能力,且具有较好的重复性.

Design and Applications of IR Detector Based on LiTaO3 Crystal Thin Wafer

The thinning technology of lithium tantalite（LiTaO3） crystal about 10 μm was introduced,and ultra-thin wafer was fabricated with technologies including thinning,bonding,polishing,etc.into the infrared sensitive element with the steaming gold and blackening technology.Based on the infrared spectrum absorption principle,narrowband filter was integrated into the sensitive element to improve resolution and selective absorption.The sensitive element,narrow band filter,CMOS amplifier,a resistance and a capacitance for read out circuit were mounted into a TO-18 vessel to form an infrared detector with a single channel and single wavelength,whose wave band could be varied according to the demand by substituting the filter.Two TO-18 detectors,whose absorption wavelengths were（3 310±90） nm and（3 910±60） nm,respectively,were used to fabricate a mini-gas-sensor.The gas sensor can detect hydrocarbons gas,such as methane and ethane.The experiment was performed with ethane and the experimental data were analyzed.Results show that the gas sensor can detect gas up to 30 000×10^-6 and the resolution reaches 100×10^-6,and has good repeatability.