Reconfigurable microwave low-pass filter containing MEMS switch and its manufacturing method

Abstract

The invention relates to a reconfigurable microwave low-pass filter containing an MEMS switch and the preparation thereof. The filter is an integrated circuit which is produced on a substrate of a high-resistance silicon wafer, an inductive reactance element is composed of a CPW ground wire and a signal wire; on one hand, the MEMS switch constitutes a capacitive reactance element, on the other hand, the MEMS switch leads the frequency of the filter to be adjustable by changing the length of the coplanar waveguide by the switching-on and off. The filter takes the high-resistance silicon wafer as the substrate, uses the process which is compatible with the IC process to evaporate a titanium layer and a gold layer by thermal oxidation, carry out the positive photoresist lithography, the electroplating and the negative photoresist lithography, corrode the gold layer and the titanium layer, remove a negative photoresist, lead a silicon nitride film to grow, remove the silicon nitride film,evaporate and deposit an aluminum-silicon alloy film, corrode the aluminum-silicon alloy film to form a bridge film, remove a sacrificial layer, and the like, for the preparation, and the filter has the advantages of compact and simple structure, small size, good isolation, low insertion loss, low power consumption of a control circuit, high working frequency, compatibility with the traditional IC process and low cost, and is applicable to mass production.

Description

technical field [0001] The invention relates to a reconfigurable microwave low-pass filter containing a MEMS (micro-electro-mechanical) switch and its preparation, belonging to the technical field of micro-mechanical systems and microwave intersections. Background technique [0002] Reconfigurable microwave low-pass filter is one of the important components in microwave wireless communication system. It can significantly reduce the size of the multi-band analog receiving front-end subsystem, suppress strong signal interference and realize multi-band conversion, especially in the millimeter wave band, which can better reflect its high performance quality. [0003] Traditional reconfigurable microwave low-pass filters are based on coaxial lines or microstrip lines, and are fabricated on printed circuit boards (PCBs). Filters generally use PIN diode switches and FET switches to adjust the filter frequency, and these switches require a large number of bias circuits, which makes...

AI Technical Summary

Problems solved by technology

[0003]Traditional reconfigurable microwave low-pass filters are based on coaxial lines or microstrip lines, and are fabricated on printed circuit boards (PCBs). Integrated with IC technology, in addition, traditional reconfigurable microwave low-pass filters generally use PIN diode switches and FET switches to achieve adjustable filter frequency, and these switches require a large number of bias circuits, making the insertion loss of the filter Large and bulky, not suitable for small RF receiver front-end applications

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