Micromachined low-loss microwave switches

• Published in: Journal of microelectromechanical systems Vol. 8; no. 2; pp. 129 - 134
• Main Authors: Yao, Z.J., Chen, S., Eshelman, S., Denniston, D., Goldsmith, C.
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01-06-1999; Institute of Electrical and Electronics Engineers
• Subjects: Applied sciences; Biomembranes; Circuit properties; Devices; Dielectric films; Electric, optical and optoelectronic circuits; Electrodes; Electronics; Exact sciences and technology; Fabrication; Membranes; Microelectromechanical devices; Microelectronic fabrication (materials and surfaces technology); Micromachining; Micromechanical devices; Microwave antenna arrays; Microwave circuits; Microwave circuits, microwave integrated circuits, microwave transmission lines, submillimeter wave circuits; Microwave devices; Microwave switching; Microwaves; Noise levels; Phased arrays; Radar antennas; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Shape; Switches; Switching; Switching networks; Voltage; Design; Microelectronic fabrication; Radio wave; Microwave device; Microwave circuit; Surface micromachining; Capacitive circuit; Selector switch; Production process
• ISSN: 1057-7157; 1941-0158
• DOI: 10.1109/84.767108

The design and fabrication of a micromechanical capacitive membrane microwave switching device is described. The switching element consists of a thin metallic membrane, which has two states, actuated or unactuated, depending on the applied bias. A microwave signal is switched on and off when the membrane is switched between the two states. These switches have a switching on speed of less than 6 /spl mu/s and a switching off speed of less than 4 /spl mu/s. The switching voltage is about 50 V. The switches have a bowtie shape and showed low insertion loss of 0.14 dB at 20 GHz and 0.25 dB at 35 GHz, and isolation of 24 dB at 20 GHz and 35 dB at 35 GHz. These devices offer the potential for building a new generation of low-loss high-linearity microwave circuits for a variety of phased antenna arrays for radar and communications applications.