Microwave High T{sub}c Superconductor MEM Switch-Based Circuits - the Current State-of-the-Art - Design and Performance Considerations

摘要

A summary of the current state of the art in MEM switches using high T{sub}C superconducting transmission line elements is presented. The most significant advantages of the MEM technology are the low mass and volume of the implemented devices. On the other hand one of the principal drawbacks of the room temperature MEM rf-switches are their losses. These are primarily resistive losses in the waveguide structure and contacts and are large due to the dimensions required (on the order of 100 μm wide by 3 μm thick). This places serious limitations on their use in noise/loss sensitive applications. The use of superconductors for the waveguide elements in MEM switches can reduce these losses very significantly (several orders of magnitude are not unusual in devices with identical dimensions). Adding a high dielectric constant insulator to the switch can also help shrink the necessary dimensions or extend the low frequency response of the switch.