The Characteristics Of Silicon Based Mems Filter Research

With the rapid development of the micro-electro-mechanical systems (MEMS), the production of silicon MEMS filter gradually attaches great importance to scholars. The filter has been subjected to the academic attention because it contains a huge market potential. Traditional microwave filters are often bulky and difficult to achieve the requirements of the technical indicators, but MEMS filter with the advantages of small size, light weight, small insertion loss, is the realization way of the RF system of miniaturization and the integration. The innovative design of silicon MEMS filter in this paper is mainly reflected in the combine of SIW technology and silicon micro-technology, adopting ICP deep etching micro-mechanical through-hole array technology to form the equivalent of the silicon substrate metal wall, and digging the metal holes on SIR microstrip to achieve the resonant structure, adopting CPW coplanar waveguide form of input and output line. The simulation results show that this filter has the better characteristics of a small size, low insertion loss, inhibition of the filtering and far parasitic passband.The paper also designed the C-band holes coupled microstrip bandpass filter, the upper metal of dielectric substrate is microstrip signal line and the lower metal layer is ground, the number of through-hole and the spacing of the holes can form different length of resonant cavity. Paper designed the third and fourth order bandpass filters and analyzed the models in detail based on the E mask loading on chip and the inductive through-hole equivalent theory. The advantages of this type model are a simple structure, easy to process, stable performance, in favor of integration of planar microstrip circuits. Finally, the HFSS simulation results show that this type of filter has low insertion loss, wide bandwidth, inhibition better, existing transmission zeros in the low-frequency and far parasitic characteristics, and according to the comparative analysis, the suppression characteristics of fourth-order filter is better, but the insertion loss of third-order filter is relatively low. Finally, the test results of processing using the vector network analyzer show that the test curve are in good agreement with the simulation curve.