三次泛音单片式、高频及高阻带晶体滤波器

3rd Overtone Monolithic Crystal Filter With High Frequency and High Stop Band

研究了三次泛音模式下单片式晶体滤波器的设计方法、制作工艺。通过优化滤波器结构、合理控制晶片镀回频率等方法,实现了晶体滤波器的高阻带和高杂波抑制。制作出一种工作频率为41.4MHz,响应模式为三次泛音的单片式晶体滤波器。结果表明,该晶体滤波器的-1dB带宽为2.9kHz,带内波动为0.3dB,阻带抑制为82dB。

The design method and fabrication process of 3rd overtone monolithic crystal filter have been studied in this paper. By optimizing the filter structure and reasonably controlling the frequency after wafer being evaporated, the high stop band suppression and high clutter suppression of the filter are realized. A monolithic crystal filter with operating frequency of 41.4 MHz and response mode of 3rd overtone has been fabricated. The experimental results show that the crystal filter has -1 dB bandwidth of 2.9 kHz, pass band ripple of 0.3 dB and stop band suppression of 82 dB.