以四面体非晶碳为布拉格反射栅高声阻抗材料的固贴式薄膜体声波谐振器性能仿真分析  

Simulation analysis of SMR with tetrahedral amorphous carbon as high impedance material of Bragg reflection

作　　者：陆晓欣[1] 朱嘉琦[1] 王赛[1] 刘罡[1] 刘远鹏[1] 袁欣薇[1] 霍施宇[1] 

机构地区：[1]哈尔滨工业大学复合材料与结构研究所,黑龙江哈尔滨150080

出　　处：《功能材料》2012年第14期1872-1875,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(51072039;50972031);教育部新世纪优秀人才支持计划资助项目(NCET-10-0070);黑龙江省自然科学基金资助项目(QC2009C56)

摘　　要：为了提高固贴式薄膜体声波谐振器(SMR)的电学和声学品质,实现四面体非晶碳(ta-C)在体声波器件领域的新应用,建立了以ta-C为布拉格反射栅高声阻抗材料的SMR模型,利用MathCAD仿真研究布拉格反射栅层数对该SMR的谐振特性的影响以及ta-C中sp3杂化含量和高/低声阻抗层厚度偏差对SMR的品质因子(Q值)的影响。结果表明层数的增加提高了SMR的品质;ta-C薄膜sp3杂化含量越高,达到饱和Q值所需层数越少,当含量为80%时,至少需要6层(3对)布拉格反射层使SMR达到优异Q值;距离压电堆越近的高/低声阻抗层,其厚度偏差对Q值的影响越大,从而实现了高频率(8GHz)低损耗的SMR的设计。To improve the electricity and acoustic quality of solidly mounted resonator（SMR）,realize the new application of tetrahedral amorphous carbon（ta-C） in the field of bulk acoustic wave device,a SMR was designed with ta-C as the high acoustic impedance Bragg reflector,which to simulate the effect of the Bragg reflector to the properties of SMR,as well as the influence of the sp3 fraction in ta-C and the error of thickness of high/low acoustic impedance layers on quality factor（Q） by MathCAD.The simulation results showed that the quality of SMR was improved with the increase of Bragg reflectors.With higher sp3 fraction,saturated Q factor can be reached with fewer layers,and there should be only six layers（three pairs） in order to get an excellent Q factor when the sp3 fraction in ta-C was 80%.The thickness error of high/low acoustic impedance layers closer to the piezoelectric stack had greater effect to Q factor.So the design of SMR with high frequency（8GHz） and low loss has been realized.

关 键 词：固贴式薄膜体声波谐振器 四面体非晶碳 布拉格反射栅 品质因子 

分 类 号：TN713[电子电信—电路与系统]