ZnO修饰多针-板结构负电晕放电气体传感器  

A ZnO Modified Multi-Needle-to-Plate Gas Sensor Based on Negative Corona Discharge

作　　者：杨天辰 张金英[1] 何秀丽[1] 高晓光[1] 贾建[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 [2]中国科学院大学,北京100190

出　　处：《微纳电子技术》2017年第7期458-464,共7页Micronanoelectronic Technology

基　　金：国家自然科学基金资助项目(61271148)

摘　　要：基于负电晕放电原理的气体传感器利用局部高压电场将目标气体电离,根据电离特性对气体进行识别。采用MEMS技术制备硅尖阵列电极,利用电喷ZnO纳米颗粒对电极表面进行修饰,结合金平板正电极构建了多针-板结构电晕放电气体传感器。研究了电极间距对传感器负电晕放电特性的影响,综合考虑起晕电压、信号输出范围及稳定放电范围,优化电极间距为100μm。测试了在-0.70 kV放电电压下传感器对乙酸气体的敏感特性。该传感器对乙酸气体的响应灵敏度约为1.05 mV/10-6,理论检测限(三倍噪声)约为8.6×10-6,测试范围内传感器响应同乙酸气体体积分数近似呈线性关系。实验结果表明,ZnO纳米颗粒修饰减小了放电尖端曲率半径,增加了放电尖端个数,消除了硅尖阵列之间高度和顶端曲率半径的差异,从而有效降低了起晕电压,提高了传感器对乙酸气体响应灵敏度及电晕放电的稳定性。The gas sensor based on negative corona discharge identifies the gases according to their ionization properties by ionizing the target gas with local high voltage electric field.The silicon tips array as a negative electrode was fabricated with the MEMS technology and the electrode surface was modified with the electrosprayed ZnO nanoparticles.A multi-needle-to-plate gas sensor based on corona discharge was designed and fabricated with the gold-sputtered plate as a positive electrode.The effect of the electrode spacing on the negative corona discharge characteristics of the sensor was investigated.Considering the onset voltage,output signal and stable discharge range,the electrode spacing was optimized to 100μm.The sensing properties of the sensor to acetic acid gas were investigated with the applied discharging voltage of-0.7 kV.The response sensitivity of the sensor to acetic acid gas is about 1.05 mV/10-6,and the theoretical detection limit based on three times the base line noise is about 8.6×10-6.The sensor response and acetic acid gas volume fraction exhibit an approximately linear relationship within the test range.The experimental results show that ZnO nanoparticle modification effectively reduces the curvature radius of the discharge tip,increases the number of discharge tip,and eliminates the differences of the height and top curvature radius of the silicon tip arrays.Then the corona onset voltage decreases effectively,and the sensitivity of the sensor to acetic acid gas and stability of corona discharge increase.

关 键 词：负电晕放电 微电子机械系统(MEMS) 硅尖阵列 ZnO修饰 气体传感器 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TH703[自动化与计算机技术—控制科学与工程]