Abstract:
A device and a method are described which hermetically seals at least one microstructure within a cavity. Electrical access to the at least one microstructure is provided by through wafer vias formed through a via substrate which supports the at least one microstructure on its front side. The via substrate and a lid wafer may form a hermetic cavity which encloses the at least one microstructure. The through wafer vias are connected to bond pads located outside the cavity by an interconnect structure formed on the back side of the via substrate. Because they are outside the cavity, the bond pads may be placed inside the perimeter of the bond line forming the cavity, thereby greatly reducing the area occupied by the device. The through wafer vias also shorten the circuit length between the microstructure and the interconnect, thus improving heat transfer and signal loss in the device.
Abstract:
A MEMS switch includes a substrate, at least one signal line and at least one electrode formed on the substrate, and a moving beam disposed in a spaced-apart relation with respect to the substrate above the substrate so as to be connected with or disconnected from the signal line according to an operation of the electrode. The moving beam includes at least one body, and at least one support to support the body. The body has a modulus of elasticity larger than that of the support. The MEMS switch prevents the moving beam from being stuck and increases a contact force generating between the moving beam and the signal line, thereby enabling a signal to be stably transmitted.
Abstract:
A microelectromechanical device is provided which includes a beam configured to apply an opening force on a closed switch. The opening force may be substantially independent of a force stored in the closed switch. A combination of the force applied by the beam and the force stored in the closed switch may be sufficient to open the switch after removal of a force associated with actuation of the switch. Another microelectromechanical device includes a switch beam spaced above a closing gate and a contact structure. The device may also include an additional beam configured to apply a force on the switch beam in a direction away from the contact structure. A method for opening a switch includes reducing an attractive force between a switch beam and a closing gate. The method also includes externally applying a mechanical force on the switch beam in a direction away from the closing gate.
Abstract:
Disclosed are an RF MEMS switch and a fabrication method thereof. The RF MEMS switch is actuated with a low voltage and a low consumption power by using a piezoelectric capacitor actuated by being converted to mechanical energy from electric energy when an electric field is applied to the piezoelectric capacitor. A cap substrate is formed by using an etching method, a chemical mechanical polishing method, an electroplating method, etc., and the RF MEMS switch has a high reliability and a high yield.
Abstract:
Trilayered Beam MEMS Device and Related Methods. According to one embodiment, a method for fabricating a trilayered beam is provided. The method can include depositing a sacrificial layer on a substrate and depositing a first conductive layer on the sacrificial layer. The method can also include forming a first conductive microstructure by removing a portion of the first conductive layer. Furthermore, the method can include depositing a structural layer on the first conductive microstructure, the sacrificial layer, and the substrate and forming a via through the structural layer to the first conductive microstructure. Still furthermore, the method can include the following: depositing a second conductive layer on the structural layer and in the via; forming a second conductive microstructure by removing a portion of the second conductive layer, wherein the second conductive microstructure electrically communicates with the first conductive microstructure through the via; and removing a sufficient amount of the sacrificial layer so as to separate the first conductive microstructure from the substrate, wherein the structural layer is supported by the substrate at a first end and is freely suspended above the substrate at an opposing second end.
Abstract:
Electrothermal Self-Latching MEMS Switch and Method. According to one embodiment, a microscale switch having a movable microcomponent is provided and includes a substrate having a stationary contact. The switch can also include a structural layer having a movable contact positioned for contacting the stationary contact when the structural layer moves toward the substrate. An electrothermal latch attached to the structural layer and having electrical communication with the movable contact to provide current flow between the electrothermal latch and the stationary contact when the movable contact contacts the stationary contact for maintaining the movable contact in contact with the stationary contact.
Abstract:
A microelectromechanical system (MEMS) switch having a high-resonance-frequency beam is disclosed. The MEMS switch includes first and second spaced apart electrical contacts, and an actuating electrode. The beam is adapted to establish contact between the electrodes via electrostatic deflection of the beam as induced by the actuating electrode. The beam may have a cantilever or bridge structure, and may be hollow or otherwise shaped to have a high resonant frequency. Methods of forming the high-speed MEMS switch are also disclosed.
Abstract:
The invention provides tapered-width micro-cantilevers and micro-bridges that give additional design parameters for controlling and synthesizing pull-in (i.e., actuation) voltages. The pull-in voltage of a tapered-width micro-cantilever is generally a function of the taper function of the width along the length, the initial width, and the length of the micro-cantilever. By controlling these design parameters, a specific pull-in voltage for a micro-cantilever is obtained. The formula for a pull-in voltage is determined based on the geometry of the micro-cantilever device and a plurality of derived pull-in voltages. The pull-in voltage is derived by iteratively solving a displacement vector as a function of applied voltage across the micro-cantilever device and setting the pull-in voltage to the voltage at which the solution does not converge. The formula is derived for linear-tapered width, parabolic-tapered width and exponential-tapered width micro-cantilevers.
Abstract:
A micro-machine switch in accordance with the present invention includes a supporter having a predetermined height relative to a surface of a substrate, a flexible cantilever projecting from the supporter in parallel with a surface of the substrate, and having a distal end facing a gap formed between two signal lines, a contact electrode formed on the cantilever, facing the gap, a lower electrode formed on the substrate in facing relation with a part of the cantilever, and an intermediate electrode formed on the cantilever in facing relation with the lower electrode. The micro-machine switch can operate at a lower drive voltage than a voltage at which a conventional micro-machine switch operates, and can enhance a resistance of an insulating film against a voltage.
Abstract:
A monolithically integrated, electromechanical microwave switch, capable of handling signals from DC to millimeter-wave frequencies, and an integrated electromechanical tunable capacitor are described. Both electromechanical devices include movable beams actuated either by thermo-mechanical or by electrostatic forces. The devices are fabricated directly on finished silicon-based integrated circuit wafers, such as CMOS, BiCMOS or bipolar wafers. The movable beams are formed by selectively removing the supporting silicon underneath the thin films available in a silicon-based integrated circuit technology, which incorporates at least one polysilicon layer and two metallization layers. A cavity and a thick, low-loss metallization are used to form an electrode above the movable beam. A thick mechanical support layer is formed on regions where the cavity is located, or substrate is bulk-micro-machined, i.e., etched.