Based on cavity resonance and sandwich composite plate （3D） theoretical model for frequency dispersion characterization theory, this paper presents a universal three-dimensional and displacement profile shapes of th...Based on cavity resonance and sandwich composite plate （3D） theoretical model for frequency dispersion characterization theory, this paper presents a universal three-dimensional and displacement profile shapes of the film bulk acoustic resonator （FBARs）. This model provides results of FBAR excited thickness-extensional and flexure modes, and the result of frequency dispersion is proposed in which the thicknesses and impedance of the electrodes and the piezoelectric material are taken into consideration; its further simplification shows good agreement with the modified Butterworth-Van-Dyke （MBVD） model. The displacement profile reflects the vibration stress distribution of electrode shapes and the lateral resonance effect, which depends on the axis ratio of the electrode shapes a/b. The results are consistent with the 3D finite element method modeling and laser interferometry measurement in general.展开更多
Tunable and switchable Ba 0.5 Sr 0.5 TiO 3 film bulk acoustic resonators（FBARs） based on SiO 2 /Mo Bragg reflectors are explored,which can withstand high temperature for the deposition of Ba x Sr 1 x TiO 3（BST） fi...Tunable and switchable Ba 0.5 Sr 0.5 TiO 3 film bulk acoustic resonators（FBARs） based on SiO 2 /Mo Bragg reflectors are explored,which can withstand high temperature for the deposition of Ba x Sr 1 x TiO 3（BST） films at 800 C.The dc bias-dependent resonance may be attributed to the piezoelectricity of the BST film induced by an electrostrictive effect.The series resonant frequency is strongly dc bias-dependent and shifts downwards with dc bias increasing,while the parallel resonant frequency is only weakly dc bias-dependent and slightly shifts upwards at low dc bias（ 45 V） while downwards at higher dc bias.The calculated relative tunability of shifts at series resonance frequency is around 2.3% and the electromechanical coupling coefficient is up to approximately 8.09% at 60-V dc bias,which can be comparable to AlN FBARs.This suggests that a high-quality tunable BST FBAR device can be achieved through the use of molybdenum（Mo） as the high acoustic impedance layer in a Bragg reflector,which not only provides excellent acoustic isolation from the substrate,but also improves the crystallinity of BST films withstanding higher deposition temperature.展开更多
Contactless acoustic manipulation of micro/nanoscale particles has attracted considerable attention owing to its near independence of the physical and chemical properties of the targets,making it universally applicabl...Contactless acoustic manipulation of micro/nanoscale particles has attracted considerable attention owing to its near independence of the physical and chemical properties of the targets,making it universally applicable to almost all biological systems.Thin-film bulk acoustic wave(BAW)resonators operating at gigahertz(GHz)frequencies have been demonstrated to generate localized high-speed microvortices through acoustic streaming effects.Benefitting from the strong drag forces of the high-speed vortices,BAW-enabled GHz acoustic streaming tweezers(AST)have been applied to the trapping and enrichment of particles ranging in size from micrometers to less than 100 nm.However,the behavior of particles in such 3D microvortex systems is still largely unknown.In this work,the particle behavior(trapping,enrichment,and separation)in GHz AST is studied by theoretical analyses,3D simulations,and microparticle tracking experiments.It is found that the particle motion in the vortices is determined mainly by the balance between the acoustic streaming drag force and the acoustic radiation force.This work can provide basic design principles for AST-based lab-on-a-chip systems for a variety of applications.展开更多
This paper presents a bulk acoustic wave piezoelectric disk resonator based on a special pair of degenerative modes, to detect z-axis angular velocity. A single piezoelectric disk is operated in its appropriate modes ...This paper presents a bulk acoustic wave piezoelectric disk resonator based on a special pair of degenerative modes, to detect z-axis angular velocity. A single piezoelectric disk is operated in its appropriate modes in the k Hz frequency range to achieve this function. This design combines the bulk acoustic wave drive/sense mode with lead zirconate titanate resonator which improves device's performance and simplifies its structural complexity. The operation principle of piezoelectric disk resonator is given and validated by finite element method,and the scale factor of piezoelectric disk resonator is 0.977 μV/[(°) · s-1] without any amplification section.The results of impedance analysis for the prototype in the air, which is fabricated on lead zirconate titanate wafer by Micro-Electro-Mechanical System process, show that the resonant frequency of the piezoelectric disk resonator is about 190 k Hz. Moreover, the measured frequency split between drive and sense mode is about290 Hz without any tuning methods. At last, a closed-loop driving and detecting circuit system is designed and its modulation/demodulation method is studied, preliminary experiments show that this device is not sensitive to acceleration, but is sensitive to angular velocity, its performance parameters need follow-up experiments.展开更多
Bulk acoustic wave resonators with piezoelectric films have been widely explored for the small size and high quality factor （Q） at GHz. This paper describes a high overtone bulk acoustic resonator （HBAR） based on ...Bulk acoustic wave resonators with piezoelectric films have been widely explored for the small size and high quality factor （Q） at GHz. This paper describes a high overtone bulk acoustic resonator （HBAR） based on AI/ZnO/AI sandwich layers and c-axis sapphire substrate. ZnO film with high quality c-axis orientation has been obtained using DC magnetron sputtering. The fabricated HBAR presents high Q at the multiple resonances from a 0.5-4.0 GHz wide band with a total size （including the contact pads） of 0.6 mm×0.3 mm×0.4 mm, The device exhibits the best acoustic coupling at around 2.4 GHz, which agrees with the simulation results based on the one-dimensional Mason equivalent circuit model. The HBAR also demonstrates Q values of 30 000, 25 000, and 6500 at 1.49, 2.43, and 3.40 GHz, respectively. It is indicated that the HBAR has potential applications for the low phase noise high frequency oscillator or microwave signal source.展开更多
针对无人机测控应用设计了一种S波段窄带带通体声波(BAW)滤波器,其技术指标为:中心频率2.46 GHz,带宽41 MHz,带内插损大于-3 d B,带内纹波小于1 d B,带外抑制小于-40 d B@2.385 GHz和2.506 GHz。采用Mason模型设计了BAW滤波器中各薄膜...针对无人机测控应用设计了一种S波段窄带带通体声波(BAW)滤波器,其技术指标为:中心频率2.46 GHz,带宽41 MHz,带内插损大于-3 d B,带内纹波小于1 d B,带外抑制小于-40 d B@2.385 GHz和2.506 GHz。采用Mason模型设计了BAW滤波器中各薄膜体声波谐振器(FBAR)的叠层结构;使用变迹法设计了各FBAR(电极)的形状;采用一种自行开发的自动布局方法得到紧凑的BAW滤波器布局;建立了BAW滤波器的声-电磁协同仿真模型,通过这种高保真的多物理场仿真方法对设计结果进行了性能验证。该设计流程是通用的,并且有两个特点:采用声-电磁协同仿真方法对设计阶段的BAW滤波器进行最终性能检验,可以及早发现并拒绝1D Mason模型过于乐观的设计;滤波器布局设计中采用了一种新的自动化布局方法,大大简化了在此阶段的反复尝试工作,也为声-电磁协同仿真模型输出了必需的面内结构信息。展开更多
体声波(BAW)双工器中Rx滤波器对Tx滤波器的负载效应,会使Tx滤波器的插入损耗性能退化而带外抑制性能过剩,进而使得BAW双工器性能不佳。为了解决这一问题,提出了一种BAW双工器的优化设计方法。设置BAW双工器中Tx滤波器的串联薄膜体声波...体声波(BAW)双工器中Rx滤波器对Tx滤波器的负载效应,会使Tx滤波器的插入损耗性能退化而带外抑制性能过剩,进而使得BAW双工器性能不佳。为了解决这一问题,提出了一种BAW双工器的优化设计方法。设置BAW双工器中Tx滤波器的串联薄膜体声波谐振器(FBAR)单元谐振区面积,及并联FBAR单元与串联FBAR单元谐振区面积比值为两组优化变量,通过牺牲Tx滤波器过剩带外抑制性能的方式,采用基于梯度的优化算法计算得到了两组优化变量的最终取值。以一个工作在FDD-LTE band 7的BAW双工器优化设计案例展示了该方法的应用流程。优化设计结果的仿真验证表明,Tx滤波器的插入损耗性能从2dB提升至1.1dB,带内波动性能从1dB提升至0.3dB。由此验证了该方法的可行性。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61275081)
文摘Based on cavity resonance and sandwich composite plate （3D） theoretical model for frequency dispersion characterization theory, this paper presents a universal three-dimensional and displacement profile shapes of the film bulk acoustic resonator （FBARs）. This model provides results of FBAR excited thickness-extensional and flexure modes, and the result of frequency dispersion is proposed in which the thicknesses and impedance of the electrodes and the piezoelectric material are taken into consideration; its further simplification shows good agreement with the modified Butterworth-Van-Dyke （MBVD） model. The displacement profile reflects the vibration stress distribution of electrode shapes and the lateral resonance effect, which depends on the axis ratio of the electrode shapes a/b. The results are consistent with the 3D finite element method modeling and laser interferometry measurement in general.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60871049 and 50972024)
文摘Tunable and switchable Ba 0.5 Sr 0.5 TiO 3 film bulk acoustic resonators（FBARs） based on SiO 2 /Mo Bragg reflectors are explored,which can withstand high temperature for the deposition of Ba x Sr 1 x TiO 3（BST） films at 800 C.The dc bias-dependent resonance may be attributed to the piezoelectricity of the BST film induced by an electrostrictive effect.The series resonant frequency is strongly dc bias-dependent and shifts downwards with dc bias increasing,while the parallel resonant frequency is only weakly dc bias-dependent and slightly shifts upwards at low dc bias（ 45 V） while downwards at higher dc bias.The calculated relative tunability of shifts at series resonance frequency is around 2.3% and the electromechanical coupling coefficient is up to approximately 8.09% at 60-V dc bias,which can be comparable to AlN FBARs.This suggests that a high-quality tunable BST FBAR device can be achieved through the use of molybdenum（Mo） as the high acoustic impedance layer in a Bragg reflector,which not only provides excellent acoustic isolation from the substrate,but also improves the crystallinity of BST films withstanding higher deposition temperature.
基金The authors gratefully acknowledge financial support from the National Key R&D Program of China(2018YFE0118700)the Natural Science Foundation of China(NSFC No.62174119)+1 种基金Tianjin Applied Basic Research and Advanced Technology(17JCJQJC43600)the 111 Project(B07014).
文摘Contactless acoustic manipulation of micro/nanoscale particles has attracted considerable attention owing to its near independence of the physical and chemical properties of the targets,making it universally applicable to almost all biological systems.Thin-film bulk acoustic wave(BAW)resonators operating at gigahertz(GHz)frequencies have been demonstrated to generate localized high-speed microvortices through acoustic streaming effects.Benefitting from the strong drag forces of the high-speed vortices,BAW-enabled GHz acoustic streaming tweezers(AST)have been applied to the trapping and enrichment of particles ranging in size from micrometers to less than 100 nm.However,the behavior of particles in such 3D microvortex systems is still largely unknown.In this work,the particle behavior(trapping,enrichment,and separation)in GHz AST is studied by theoretical analyses,3D simulations,and microparticle tracking experiments.It is found that the particle motion in the vortices is determined mainly by the balance between the acoustic streaming drag force and the acoustic radiation force.This work can provide basic design principles for AST-based lab-on-a-chip systems for a variety of applications.
基金the Special New Century Excellent Talents Support Program of Ministry of Education(No.NCET-10-0583)the National Key Laboratory of Science and Technology on Nano/Micro Fabrication(No.9140C790405110C7904)+2 种基金Preresearch Fund(No.9140A09010312JW03104)Fund(No.2013ZC57003)the Graduate Innovation Program of Shanghai Jiao Tong University(No.Z-340-014)
文摘This paper presents a bulk acoustic wave piezoelectric disk resonator based on a special pair of degenerative modes, to detect z-axis angular velocity. A single piezoelectric disk is operated in its appropriate modes in the k Hz frequency range to achieve this function. This design combines the bulk acoustic wave drive/sense mode with lead zirconate titanate resonator which improves device's performance and simplifies its structural complexity. The operation principle of piezoelectric disk resonator is given and validated by finite element method,and the scale factor of piezoelectric disk resonator is 0.977 μV/[(°) · s-1] without any amplification section.The results of impedance analysis for the prototype in the air, which is fabricated on lead zirconate titanate wafer by Micro-Electro-Mechanical System process, show that the resonant frequency of the piezoelectric disk resonator is about 190 k Hz. Moreover, the measured frequency split between drive and sense mode is about290 Hz without any tuning methods. At last, a closed-loop driving and detecting circuit system is designed and its modulation/demodulation method is studied, preliminary experiments show that this device is not sensitive to acceleration, but is sensitive to angular velocity, its performance parameters need follow-up experiments.
基金Project (Nos. 11074274 and 11174319) supported by the National Natural Science Foundation of China
文摘Bulk acoustic wave resonators with piezoelectric films have been widely explored for the small size and high quality factor （Q） at GHz. This paper describes a high overtone bulk acoustic resonator （HBAR） based on AI/ZnO/AI sandwich layers and c-axis sapphire substrate. ZnO film with high quality c-axis orientation has been obtained using DC magnetron sputtering. The fabricated HBAR presents high Q at the multiple resonances from a 0.5-4.0 GHz wide band with a total size （including the contact pads） of 0.6 mm×0.3 mm×0.4 mm, The device exhibits the best acoustic coupling at around 2.4 GHz, which agrees with the simulation results based on the one-dimensional Mason equivalent circuit model. The HBAR also demonstrates Q values of 30 000, 25 000, and 6500 at 1.49, 2.43, and 3.40 GHz, respectively. It is indicated that the HBAR has potential applications for the low phase noise high frequency oscillator or microwave signal source.
文摘针对无人机测控应用设计了一种S波段窄带带通体声波(BAW)滤波器,其技术指标为:中心频率2.46 GHz,带宽41 MHz,带内插损大于-3 d B,带内纹波小于1 d B,带外抑制小于-40 d B@2.385 GHz和2.506 GHz。采用Mason模型设计了BAW滤波器中各薄膜体声波谐振器(FBAR)的叠层结构;使用变迹法设计了各FBAR(电极)的形状;采用一种自行开发的自动布局方法得到紧凑的BAW滤波器布局;建立了BAW滤波器的声-电磁协同仿真模型,通过这种高保真的多物理场仿真方法对设计结果进行了性能验证。该设计流程是通用的,并且有两个特点:采用声-电磁协同仿真方法对设计阶段的BAW滤波器进行最终性能检验,可以及早发现并拒绝1D Mason模型过于乐观的设计;滤波器布局设计中采用了一种新的自动化布局方法,大大简化了在此阶段的反复尝试工作,也为声-电磁协同仿真模型输出了必需的面内结构信息。
文摘体声波(BAW)双工器中Rx滤波器对Tx滤波器的负载效应,会使Tx滤波器的插入损耗性能退化而带外抑制性能过剩,进而使得BAW双工器性能不佳。为了解决这一问题,提出了一种BAW双工器的优化设计方法。设置BAW双工器中Tx滤波器的串联薄膜体声波谐振器(FBAR)单元谐振区面积,及并联FBAR单元与串联FBAR单元谐振区面积比值为两组优化变量,通过牺牲Tx滤波器过剩带外抑制性能的方式,采用基于梯度的优化算法计算得到了两组优化变量的最终取值。以一个工作在FDD-LTE band 7的BAW双工器优化设计案例展示了该方法的应用流程。优化设计结果的仿真验证表明,Tx滤波器的插入损耗性能从2dB提升至1.1dB,带内波动性能从1dB提升至0.3dB。由此验证了该方法的可行性。
