Study on Film Bulk Acoustic Wave Filter for Wireless Communication

• Main Authors: Chi-Ming Fang, 方啟銘
• Other Authors: Pei-Zen Chang
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/82773756027291321926

博士 === 國立臺灣大學 === 應用力學研究所 === 97 === With the rapid development of wireless communication field, the potential advantages of Film bulk acoustic wave resonator (FBAR) are attractive to microelectronics researchers for bandpass filters. The advantages of FBAR include microminiaturization, high quality (Q) factor, high frequency operation, great power handling, and compatibility of complementary metal oxide semiconductor (CMOS) etc. Based on the trend, this research proposes to develop film bulk acoustic wave (FBAW) filters for radio frequency (RF) front-end modules. This thesis completely includes design, simulation, fabrication, measurement, and analysis of the FBAW filters. A FBAW filter cnsists of several FBAR components. Therefore, the electrical impedance characteristic of the FBAR is derived first. Then, a complete design methed of FBAW filters utilizing traditional ladder type filters concept is proposed in this study. Furthermore, this research demonstrates the equivalent circuit model of FBAW devices in electronic design automation (EDA) simulation software to rapidly design and simulate the FBAW device with circuitry on a single platform. This simulation model is verified through comparison with experiments. It can be used of simulating accurately the characteristics of FBAW devices with/without circuit components and predicting the influence of process variation on the devices. Meanwhile, to enhance the yield of FBAW devices, the fabricated process and key factor of the FBAW devices are described clearly through micro-electro-mechanical systems (MEMS) technique. An excellent FBAW filter is dependent on the high quality factor and electromechanical coupling coefficient of the FBAR components. First, FBAR are designed and fabricated to investigate the significant parameters of the various FBARs. Next, the FBAW filters for wireless communications are developed, which includes the 2.4-GHz and 5.4-GHz FBAW filters, individually. The above FBAW filters can be applied to 802.11b/g/n, Bluetooth, and 4G-WiMAX wireless communication systems. These studies confirm FBAW filters are a great potential solution for providing the high performance bandpass filters. Finally, the integration of FBAW filters with circuitry using 0.18μm CMOS technology and post-COMS MEMS process are investigated in the thesis. The study of the FBAW filter integrated with low noise amplifier is achieved. In addition, the specific FBAW filters based on an on-off keying RF receiver are accomplished. These studies are promising that FBAW devices integrated with the RF front-end system on a chip (SOC) are feasible.