Gao Chao, Zheng Yupeng, Li Haiyang, Ren Yuqi, Gu Xiyu, Huang Xiaoming, Wang Yaxin, Qu Yuanhang, Liu Yan, Cai Yao, Sun Chengliang
The Institute of Technological Sciences, Hubei Key Laboratory of Electronic Manufacturing and Packaging Integration, Wuhan University, Wuhan 430072, China.
Hubei Yangtze Memory Laboratories, Wuhan 430205, China.
Sensors (Basel). 2024 May 5;24(9):2939. doi: 10.3390/s24092939.
Film bulk acoustic-wave resonators (FBARs) are widely utilized in the field of radio frequency (RF) filters due to their excellent performance, such as high operation frequency and high quality. In this paper, we present the design, fabrication, and characterization of an FBAR filter for the 3.0 GHz-3.2 GHz S-band. Using a scandium-doped aluminum nitride (ScAlN) film, the filter is designed through a combined acoustic-electromagnetic simulation method, and the FBAR and filter are fabricated using an eight-step lithographic process. The measured FBAR presents an effective electromechanical coupling coefficient (keff2) value up to 13.3%, and the measured filter demonstrates a -3 dB bandwidth of 115 MHz (from 3.013 GHz to 3.128 GHz), a low insertion loss of -2.4 dB, and good out-of-band rejection of -30 dB. The measured 1 dB compression point of the fabricated filter is 30.5 dBm, and the first series resonator burns out first as the input power increases. This work paves the way for research on high-power RF filters in mobile communication.
薄膜体声波谐振器（FBAR）因其优异的性能，如高工作频率和高品质因数，在射频（RF）滤波器领域得到了广泛应用。在本文中，我们展示了一款用于3.0 GHz - 3.2 GHz S波段的FBAR滤波器的设计、制造和特性表征。该滤波器采用掺钪氮化铝（ScAlN）薄膜，通过声电联合仿真方法进行设计，并使用八步法光刻工艺制造FBAR和滤波器。测得的FBAR呈现出高达13.3%的有效机电耦合系数（keff2）值，测得的滤波器显示出115 MHz的 - 3 dB带宽（从3.013 GHz到3.128 GHz）、 - 2.4 dB的低插入损耗以及 - 30 dB的良好带外抑制。所制造滤波器的测得1 dB压缩点为30.5 dBm，并且随着输入功率增加，第一个串联谐振器首先烧毁。这项工作为移动通信中高功率RF滤波器的研究铺平了道路。
