Abstract: A wet and vapor acid etching method releases a microelectromechanical systems (MEMS) structure from a substrate by dissolving a sacrificial layer disposed between the MEMS and the substrate. The sacrificial layer may be a silicon dioxide (SiO2) layer having a field portion over which the MEMS does not extend and a support portion over which the MEMS does extend. The field portion of the SiO2 layer is quickly removed using conventional wet hydrofluoric (HF) etching followed by rinsing and drying and then the support portion is removed using conventional vapor HF etching from a solution greater than 45% by weight percent. The wet HF chemical etch quickly removes the large field portion of the sacrificial layer. The HF vapor etch removes the small support portion of the sacrificial layer below the MEMS to release the MEMS from the substrate without stiction thereby preventing damage to the MEMS when released.

Abstract: A microelectromechanical system (MEMS) switch has a bidirectionally rotating member having two positions for integrated circuit connection. The switch is formed on a circular standoff bearing for rotating the switch in the plane of the substrate using conventional processing techniques. Control traces carry electrical signals generating electrical fields to provide an electro-static force upon the rotating switch member to rotate the switch clockwise or counter-clockwise to position and maintain it in either of two positions. The MEMS switch has wide applications to a variety of microelectromechanical system circuit applications.

Abstract: A method of manufacturing a micromachined reflector antenna onto a substrate firstly etches a reflector aperture surface defining a dish cavity in an oxide layer and secondly rotates a hinge over the reflector aperture surface with the hinge being used as the reflector central feed. The micromachined reflector can be made into an array of reflector antennas and integrated onto a single substrate with front end receiver circuits operating as a high frequency receiver on a chip reduced in size and cost and operating at hundreds of GHz.

Abstract: A micromachined reflector antenna system is integrated onto a substrate by firstly etching a reflector aperture surface defining a dish cavity in an oxide layer and secondly rotating a hinge over the reflector aperture surface with the hinge being used as the reflector central feed. The micromachined reflector antenna system can be made with an array of reflector antennas and integrated onto a single substrate with front end receiver circuits operating as a high frequency receiver on a chip with reduced size and cost and operating at hundreds of GHz.

Abstract: A Concentric MESFET (CMESFET) is a small-signal traveling-wave transistor having a grounded source electrode which concentrically surrounds and shields the gate and drain electrodes from electromagnetic fields generated by other nearby circuit elements. S-parameters for the transistor are computed to obtain gain curves for design configurations. For a gate length of 2 um, maximum gain occurs with a gate width of 3.0 mm. The CMESFET has calculated bandwidth of 17 GHz for a 2 um gate length and a gate width of 300 m. Coupling capacitance between device electrodes and a nearby transmission line are calculated and used to verify improved source electrode shielding isolation of the device from interference and crosstalk originating in surrounding circuits.