Integrated RF MEMS/CMOS Devices

TL;DR

This paper presents a novel maskless post-processing method for CMOS chips to create high-Q RF MEMS capacitors, enabling compact, tunable filters with significant frequency range for RF applications.

Contribution

It introduces a new fabrication technique for RF MEMS/CMOS devices and demonstrates a tunable bandpass filter with high quality factor and compact size.

Findings

Achieved a 17% tuning range at 9.5 GHz.

Fabricated a 1.2 x 2.1 mm2 tunable filter.

Demonstrated high quality factor exceeding 20.

Abstract

A maskless post-processing technique for CMOS chips is developed that enables the fabrication of RF MEMS parallel-plate capacitors with a high quality factor and a very compact size. Simulations and measured results are presented for several MEMS/CMOS capacitors. A 2-pole coupled line tunable bandpass filter with a center frequency of 9.5 GHz is designed, fabricated and tested. A tuning range of 17% is achieved using integrated variable MEMS/CMOS capacitors with a quality factor exceeding 20. The tunable filter occupies a chip area of 1.2 x 2.1 mm2.