|
Abstract: |
In this paper, a solidly mounted resonator (SMR) was designed with nanocrystalline diamond (NCD) as the high acoustic impedance material of Bragg reflector to improve the quality. We used Mathcad to investigate the effect of the Bragg reflector on the performance of the SMR, as well as the influence of different materials and the number of layers of Bragg reflector on the quality factor Q. Results show that the Bragg reflector could reduce energy loss effectively, and the higher the impedance of the high acoustic impedance layer, the better the SMR. The parasitic factors of the SMR using two high acoustic impedance materials, tungsten (W) and NCD, were also simulated by an Advanced Design System (ADS) using the Mason model. It was found that the parasitic effect caused by metal would significantly decrease the Q factor of the SMR. In the frequency range below 6 GHz, within which the SMR works normally, NCD performed better than W. Therefore, NCD is a better choice of high acoustic impedance material in the design of the SMR, with improved quality at high frequency and low loss. The optimum number of layers of Bragg reflector is 6. |
Key words: solidly mounted resonator (SMR) nanocrystalline diamond (NCD) Bragg reflector quality factor (Q) parasitic effect |
DOI:10.11916/j.issn.1005-9113.19051 |
Clc Number:O411 |
Fund: |
|
Descriptions in Chinese: |
纳米金刚石(NCD)作为固贴式薄膜体声谐振器(SMR)布拉格反射栅高声阻抗材料的理论分析 鄂羽佳,张森,代兵,朱嘉琦,韩杰才 (哈尔滨工业大学 复合材料与结构研究所,哈尔滨 150001) 中文说明:本文设计了一种采用纳米金刚石(NCD)作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(SMR),可以显著提高布拉格反射栅的性能。利用Mathcad软件研究了布拉格反射栅对SMR性能的影响,以及由不同高声阻抗材料、不同层数组成的布拉格反射栅对SMR品质因子Q的影响。结果表明,选用纳米金刚石作为高声阻抗材料的布拉格反射栅能有效地降低能量损失,且可以有效地提高SMR的性能。高声阻抗材料的声阻抗越高,SMR性能越好。建立MASON模型,利用先进设计系统(ADS)模拟了金属钨(W)和NCD两种高声阻抗材料组成的布拉格反射栅对SMR器件所产生的寄生因素的影响。结果表明,金属材料所引起的寄生效应会显著降低SMR的品质因子Q。在6 GHz以下的频率范围内,在SMR正常工作的情况下,选用NCD作为高声阻抗材料的器件性能优于W,因此,NCD是SMR设计中高声阻抗材料的较好选择,在高频和低损耗下,器件的性能得到了改善。同时,布拉格反射栅的最佳层数为6层。 关键词:固贴式薄膜体声波谐振器(SMR),纳米金刚石(NCD),布拉格反射栅,品质因子(Q),寄生效应 |