声表面波传感器结构仿真及敏感特性研究

【作者】 于海燕；

【导师】 吴志明；

【作者基本信息】 电子科技大学 ， 光学工程， 2007， 硕士

【摘要】 频率高、体积小、功能多、稳定性好、易于批量生产的声表面波器件,以其独特的性能在移动通信、航空航天、电子对抗等军用和民用领域得到了成功的应用。新兴的声表面波传感器,更是以其灵敏度高、功耗低的特点,广泛的应用于众多物理量、化学量和生物量的检测,成为传感领域的一门新兴技术,拥有巨大的发展潜力。论文分析了声表面波在传感器技术应用中的研究现状;讨论了不同压电晶体基片材料上声表面波的传输特点;应用MATLAB软件对声表面波传感器结构特性参数进行了分析和计算;对加权结构及非加权结构叉指换能器的特性进行了理论分析;采用了Remez交换算法及Firls最优化算法分析了声表面波滤波器中加权结构叉指换能器的特性,结果表明Remez交换算法具有设计灵活、容易调整的特点,对于同等性能的频域特性,可以以最少的指条对数来实现,以Firls最优化算法很容易做到精确的线性相位。对制备的酞菁铜颗粒掺杂的聚乙烯吡咯烷酮敏感薄膜进行了紫外、红外以及光电子能谱特性表征;理论分析了声表面波传输路径沉积薄膜质量变化、电导率变化及温度的变化对传感器中心频率的影响;并采用网络分析仪测试了声表面波传感器中心频率随酞菁铜颗粒掺杂的聚乙烯吡咯烷酮薄膜的质量变化关系;对制备的声表面波传感器随温度、湿度及气体吸附引起的中心频率的变化进行了详细分析和讨论;用振荡电路法对谐振型声表面波传感器敏感特性进行了测试,结果表明高频率谐振型SAW传感器比延迟线型SAW传感器具有更高的灵敏度。更多还原

【Abstract】 Due to its unique advantages such as high frequency, low volume, versatility, stability and mass production, Surface Acoustic Wave (SAW) device is successfully used in military and civilian fields including aerospace, mobile communication and electronic counter-measure, etc. The newly arisen SAW sensor is promising and gaining more and more attention for its high sensitivity and low power consumption. SAW sensor is widely used in sensitive detection of physical, chemical and biological measurands.The SAW technology in sensor applications has been reviewed. The transport model and the property of SAW in different piezoelectricity have been discussed. The frequency spectrum of one-path delayline resonance sensor has been simulated by MATLAB software. The characteristics of equal length and unequal length of IDT have been calculated. Remez exchange algorithm and the Firls optimization algorithm have been researched. Remez exchange algorithm has the merit that it can be designed flexibly and rectified facilely. For same frequency response, it can be realized preferably with the minimum number of IDT. The Firls optimization algorithm has the virtue that it can achieve precise linear phase.Copper phthalocyanine (CuPc) doped polyvinylpyrrolidone (PVP) thin film was deposited on the delayline of SAW sensor as a sensitive component, which was characterized by UV-vis absorption, IR spectra and X-ray photoelectron spectroscopy (XPS) techniques. The effects of mass variation, electric conductivity and temperature of deposited sensitive film on the central frequency of SAW sensor have theoretically been analyzed in detail. The relation between the shift of central frequency of SAW sensor and the mass variation of CuPc doped PVP film has been tested by electronic network analyses apparatus (ENA). The shift of central frequency of SAW sensor at different temperature, humidity and adsorbed gas has also been investigated. Using oscillating circuit, the property of SAW sensor has been tested. The results show that high frequency resonance SAW sensor is more sensitive than delayline type SAW sensor.更多还原