Design of Ku-band SIR interdigital bandpass filter using silicon-based micromachining technology

This paper presents design, fabrication, and measurement of a Ku-band micromachined bandpass filter. The fourth-order interdigital filterd based on step-impedance resonators (SIRs) is fabricated and self-packaged by three high-resistivity(≫ 10KΩcm) silicon wafers to achieve compactness and low loss. The proposed circuit is designed to produce a passband of 21% centered at 14.2 GHz. Experimental results exhibit that the insertion loss is 2.3dB and the return loss is better than 20 dB within passband. The fabrication technology can be applied for other micromachined devices.