基于ALN压电层的声表面波温度传感器仿真与试验研究  

Simulation and Experimental Study of SAW Temperature Sensor Based on ALN Piezoelectric Layer

作　　者：曹森 赵祉澎 刘志春 孙宏毅 陈锦斌 于晓梅 梁军生[1,2] Cao Sen;Zhao Zhipeng;Liu Zhichun;Sun Hongyi;Chen Jinbin;Yu Xiaomei;Liang Junsheng(Key Laboratory for Micro/Nano Technology and System of Liaoning Province,Dalian University of Technology,Dalian,Liaoning 116024,China;Key Laboratory for Precision and Non-traditional Machining Technologyof Ministry of Education,Dalian University of Technology,Dalian,Liaoning 116024,China)

机构地区：[1]大连理工大学辽宁省微纳米技术及系统重点实验室,辽宁大连116024 [2]大连理工大学精密与特种加工技术教育部重点实验室,辽宁大连116024

出　　处：《机电工程技术》2022年第11期174-177,共4页Mechanical & Electrical Engineering Technology

基　　金：航空科学基金资助项目(编号:2019ZD063001)。

摘　　要：传统的声表面波(SAW)温度传感器仍存在测温范围小、灵敏度低的问题,为满足对工业生产、航空航天等高温环境下的温度检测,采用了在高温下仍能保持良好压电性的ALN薄膜,确定传感器的结构为叉指换能器(IDT)/ALN/Sapphire。为了得到较高温度频率系数(TCF),进行建模仿真和计算对比,并利用激发的瑞利波模态对温度进行感知标定。分析了不同压电层厚度、金属化比率、叉指电极厚度对激发的瑞利波波速和机电耦合系数的影响,并讨论了TCF值与压电层厚度的关系。确定理想参数下的波速为5780 m/s,机电耦合系数为0.82%。利用射频磁控溅射系统在Sapphire基底上溅射了高质量C轴取向ALN薄膜,再将表面的Pt/Ta图案化成电极。试验制得的传感器在800℃以下其频率与温度呈现较好的线性关系,温度频率系数约为-53.5 ppm/℃,与仿真较为吻合。相比于传统SAW温度传感器,在测温范围增大的同时保证了高灵敏度。The traditional surface acoustic wave(SAW)temperature sensors are facing the chanllenges of small temperature range and low sensitivity in measurement.In order to meet the high temperature detection requirement in harsh environment including industrial production and aerospace,a structure of interdigital transducer(IDT)/ALN/Sapphire was designed since the ALN can maintain good piezoelectric property at high temperatures.Modeling simulation and calculation comparison were developed to obtain the high temperature frequency coefficient(TCF),and the excited Rayleigh wave mode was also used for the temperature calibration.The influences of the thickness of piezoelectric layer,metallization ratio and interdigital electrode thickness on Rayleigh wave velocity and electromechanical coupling coefficient were systematically studied respectively.In addition,the thickness of the ALN films on the TCF was also investigated.Results show that the wave velocity and electromechanical coupling coefficient can reach up to 5780 m/s and 0.82%under ideal parameters.High quality C-axis oriented ALN thin films were deposited on Sapphire substrates by RF magnetron sputtering system,and then Pt/Ta electrodes were fabricated using MEMS technique.The temperature frequency coefficient of the SAW was about-53.5 ppm/℃,and it also had a good linear relationship between frequency and temperature at 800℃,which was consistent with the results of simulation.The sensor has the larger temperature measurement range and higher sensitivity than that of the traditional SAW temperature sensor.

关 键 词：温度检测 声表面波温度传感器 温度频率系数 COMSOL仿真 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置] TN751[自动化与计算机技术—控制科学与工程]