A micromachined cavity resonator for millimeter-wave oscillator applications

High stability and low phase noise oscillators are key components in millim eter-wave (MMW) systems. Using microelectromechanical system (MEMS) technol ogy, the silicon cavity resonator has been developed for MMW oscillator app lications. Thanks to the superior e-factor of the cavity over planar resona tors, low phase noise and high stability is expected. The fabricated, micro machined cavity showed an unloaded e-factor of 120 and Ka-band voltage cont rolled oscillator (VCO) coupled with the cavity resonators showed a phase n oise improvement of more than 15 dB over free-running oscillators (FROs). T o the best of our knowledge, this is the first experimental demonstration o f a high electron mobility transistor (HEMT) microwave monolithic integrate d circuit (MMIC) oscillator combined with a micromachined cavity resonator. (C) 2000 Elsevier Science S.A. All rights reserved.