Abstract:
In a MEMS device, the manner in which the membrane lands over the RF electrode can affect device performance. Bumps or stoppers placed over the RF electrode can be used to control the landing of the membrane and thus, the capacitance of the MEMS device. The shape and location of the bumps or stoppers can be tailored to ensure proper landing of the membrane, even when over-voltage is applied. Additionally, bumps or stoppers may be applied on the membrane itself to control the landing of the membrane on the roof or top electrode of the MEMS device.
Abstract:
The present invention generally relates to a MEMS device having a plurality of cantilevers that are coupled together in an anchor region and/or by legs that are coupled in a center area of the cantilever. The legs ensure that each cantilever can move/release from above the RF electrode at the same voltage. The anchor region coupling matches the mechanical stiffness in all sections of the cantilever so that all of the cantilevers move together.
Abstract:
The present invention generally relates to an architecture for isolating an RF MEMS device from a substrate and driving circuit, series and shunt DVC die architectures, and smaller MEMS arrays for high frequency communications. The semiconductor device has one or more cells with a plurality of MEMS devices therein. The MEMS device operates by applying an electrical bias to either a pull-up electrode or a pull-down electrode to move a switching element of the MEMS device between a first position spaced a first distance from an RF electrode and a second position spaced a second distance different than the first distance from the RF electrode. The pull-up and/or pull-off electrode may be coupled to a resistor to isolate the MEMS device from the substrate.
Abstract:
In a MEMS device, the manner in which the membrane lands over the RF electrode can affect device performance. Bumps or stoppers placed over the RF electrode can be used to control the landing of the membrane and thus, the capacitance of the MEMS device. The shape and location of the bumps or stoppers can be tailored to ensure proper landing of the membrane, even when over-voltage is applied. Additionally, bumps or stoppers may be applied on the membrane itself to control the landing of the membrane on the roof or top electrode of the MEMS device.
Abstract:
The present invention generally relates to an architecture for isolating an RF MEMS device from a substrate and driving circuit, series and shunt DVC die architectures, and smaller MEMS arrays for high frequency communications. The semiconductor device has one or more cells with a plurality of MEMS devices therein. The MEMS device operates by applying an electrical bias to either a pull-up electrode or a pull-down electrode to move a switching element of the MEMS device between a first position spaced a first distance from an RF electrode and a second position spaced a second distance different than the first distance from the RF electrode. The pull-up and/or pull-off electrode may be coupled to a resistor to isolate the MEMS device from the substrate.
Abstract:
The present invention generally relates to MEMS devices and methods for their manufacture. The cantilever of the MEMS device may have a waffle-type microstructure. The waffle-type microstructure utilizes the support beams to impart stiffness to the microstructure while permitting the support beam to flex. The waffle-type microstructure permits design of rigid structures in combination with flexible supports. Additionally, compound springs may be used to create very stiff springs to improve hot-switch performance of MEMS devices. To permit the MEMS devices to utilize higher RF voltages, a pull up electrode may be positioned above the cantilever to help pull the cantilever away from the contact electrode.
Abstract:
The chill mold is mounted on a support which is rotatable about the vertical axis of its casting cavity and is composed of a lower element, an upper element which has a pouring opening, and four peripheral elements arranged in two opposing pairs. The lower element occupies a casting position on the support and coaxial therewith, the upper element is movable between a casting position in which it overlies the lower element coaxially, and a shakeout position in which it does not interfere with the upward removal of the piece from the mold, and the peripheral elements are displaceable radially on the support to allow their movement from a casting position, in which together they surround the upper and lower element, to a shakeout position in which they are further removed from the axis of rotation. The elements of the chill mold are provided with locking keys which are mutually engageable due to the movement of a first pair of the opposed peripheral elements towards their respective casting positions when the lower and upper elements and the opposed peripheral elements of the other pair are substantially in their respective casting position. Keys are also provided for locking the peripheral elements of the first pair in their respective casting positions.
Abstract:
The present invention generally relates to a MEMS device having a plurality of cantilevers that are coupled together in an anchor region and/or by legs that are coupled in a center area of the cantilever. The legs ensure that each cantilever can move/release from above the RF electrode at the same voltage. The anchor region coupling matches the mechanical stiffness in all sections of the cantilever so that all of the cantilevers move together.
Abstract:
The machine has a casting ladle mounted rotatably on a movable support member which conveys the ladle between a filling station and at least one casting station. The movable member carries a motorized rotary disc cam cooperating with a cam-follower which controls rotations of the ladle. The cam profile includes a larger sector of increasing radius to cause a pouring rotation of the ladle at the casting station and a smaller sector of decreasing radius to cause a return rotation of the ladle to the upright position after casting. The cam has, between the two sections, a profile portion which is re-entrant towards the axis of rotation of the cam and in which the cam-follower is engageable selectively to cause a sharp rotation of the ladle from the upright position to an inverted position, so as to release the skin or crust of solidified metal from the inside of the ladle when the latter is at a cleaning station. Control means are provided for avoiding engagement of the cam-follower in the re-entrant portion at least when the ladle is in the casting station, and for disengaging the cam-follower from the re-entrant portion after the inversion of the ladle.
Abstract:
Utilizing a variable capacitor for RF and microwave applications provides for multiple levels of intra-cavity routing that advantageously reduce capacitive coupling. The variable capacitor includes a bond pad that has a plurality of cells electrically coupled thereto. Each of the plurality of cells has a plurality of MEMS devices therein. The MEMS devices share a common RF electrode, one or more ground electrodes and one or more control electrodes. The RF electrode, ground electrodes and control electrodes are all arranged parallel to each other within the cells. The RF electrode is electrically connected to the one or more bond pads using a different level of electrical routing metal.