Abstract: The present invention generally relates to a MEMS DVC. The MEMS DVC has an RF electrode and is formed above a CMOS substrate. To reduce noise in the RF signal, a poly-resistor that is connected between a waveform controller and the electrodes of the MEMS element, may be surrounded by an isolated p-well or an isolated n-well. The isolated well is coupled to an RF ground shield that is disposed between the poly-resistor and the MEMS element. Due to the presence of the isolated well that surrounds the poly-resistor, the substrate resistance does not influence the dynamic behavior of each MEMS element in the MEMS DVC and noise in the RF signal is reduced.

Abstract: The present invention generally relates to a method of operating a MEMS DVC while minimizing impact of the MEMS device on contact surfaces. By reducing the drive voltage upon the pull-in movement of the MEMS device, the acceleration of the MEMS device towards the contact surface is reduced and thus, the impact velocity is reduced and less damage of the MEMS DVC device occurs.

Abstract: The present invention generally relates to a method for forming a MEMS device and a MEMS device formed by the method. When forming the MEMS device, sacrificial material is deposited around the switching element within the cavity body. The sacrificial material is eventually removed to free the switching element in the cavity. The switching element has a thin dielectric layer thereover to prevent etchant interaction with the conductive material of the switching element. During fabrication, the dielectric layer is deposited over the sacrificial material. To ensure good adhesion between the dielectric layer and the sacrificial material, a silicon rich silicon oxide layer is deposited onto the sacrificial material before depositing the dielectric layer thereon.

Abstract: The present invention generally relates to small antennas suitable for mobile devices operating in the high frequency and radio frequency bands in the range 100 MHz to 5 GHz. The antennas may be coupled to a DVC such as a MEMS DVC. The antenna may be coupled to a printed circuit board disposed inside of the mobile device, such as a mobile phone or smart phone.

Abstract: The present invention generally relates to a MEMS digital variable capacitor (DVC) (900) and a method for manufacture thereof. The movable plate (938) within a MEMS DVC should have the same stress level to ensure proper operation of the MEMS DVC. To obtain the same stress level, the movable plate is decoupled from CMOS ground during fabrication. The movable plate is only electrically coupled to CMOS ground after the plate has been completely formed. The coupling occurs by using the same layer (948) that forms the pull-up electrode as the layer that electrically couples the movable plate to CMOS ground. As the same layer couples the movable plate to CMOS ground and also provides the pull-up electrode for the MEMS DVC, the deposition occurs in the same processing step. By electrically coupling the movable plate to CMOS ground after formation, the stress in each of the layers of the movable plate can be substantially identical.

Abstract: The present invention generally relates to a MEMS DVC having a shielding electrode structure between the RF electrode and one or more other electrodes that cause a plate to move. The shielding electrode structure may be grounded and, in essence, block or shield the RF electrode from the one or more electrodes that cause the plate to move. By shielding the RF electrode, coupling of the RF electrode to the one or more electrodes that cause the plate to move is reduced and capacitance modulation is reduced or even eliminated.

Abstract: Embodiments of the present invention generally relate to a MEMS device that is anchored using the layer that is deposited to form the cavity sealing layer and/or with the layer that is deposited to form the pull-off electrode. The switching element of the MEMS device will have a flexible or movable portion and will also have a fixed or anchor portion that is electrically coupled to ground. The layer that is used to seal the cavity in which the switching element is disposed can also be coupled to the fixed or anchor portion of the switching element to anchor the fixed or anchor portion within the cavity. Additionally, the layer that is used to form one of the electrodes may be used to provide additional leverage for anchoring the fixed or anchor portion within the cavity. In either situation, the movement of the flexible or movable portion is not hindered.

Abstract: The present invention generally relates to a MEMS DVC and a method for fabrication thereof. The MEMS DVC comprises a plate movable from a position spaced a first distance from an RF electrode and a second position spaced a second distance from the RF electrode that is less than the first distance. When in the second position, the plate is spaced from the RF electrode by a dielectric layer that has an RF plateau over the RF electrode. One or more secondary landing contacts and one or more plate bend contacts may be present as well to ensure that the plate obtains a good contact with the RF plateau and a consistent Cmax value can be obtained. On the figure PB contact is the plate bend contact, SL contact is the Second Landing contact and the PD electrode is the Pull Down electrode.

Abstract: The present invention generally relates to a MEMS device and a method of manufacture thereof. The RF electrode, and hence, the dielectric layer thereover, has a curved upper surface that substantially matches the contact area of the bottom surface of the movable plate. As such, the movable plate is able to have good contact with the dielectric layer and thus, good capacitance is achieved.

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 disclosure generally relates to a device having a variable frequency filter that rejects harmonics generated by a variable reactance device. The variable frequency filter may be coupled to the antenna and the variable reactance device. The filter includes a variable capacitor and an inductor coupled together as a resonant circuit. The filter may be used in cellular technology to prevent harmonic frequencies that are created by another variable reactance device from reaching the antenna of the cellular device. Furthermore, the filter can reflect any receiving frequencies from the antenna and prevent the receiving frequencies from passing through.

Abstract: The present invention generally relates to a method of fabricating a MEMS device. In the MEMS device, a movable plate is disposed within a cavity such that the movable plate is movable within the cavity. To form the cavity, sacrificial material may be deposited and then the material of the movable plate is deposited thereover. The sacrificial material is removed to free the mov able plate to move within the cavity. The sacrificial material, once deposited, may not be sufficiently planar because the height difference between the lowest point and the highest point of the sacrificial material may be quite high. To ensure the movable plate is sufficiently planar, the planarity of the sacrificial material should be maximized. To maximize the surface planarity of the sacrificial material, the sacrificial material may be deposited and then conductive heated to permit the sacrificial material to reflow and thus, be planarized.

Abstract: A variable capacitor (300) comprises cells (200, 400) that have an RF electrode (202, 402) coupled to a bond pad (30). Each cell comprises a plurality of MEMS devices (100) the capacitance of which can be changed by means of a movable electrode. The MEMS devices are placed in a sealed cavity of the cell and are arranged next to each other along the length of the RF electrode of the cell. The RF electrode of each cell can be trimmed so as to obtain an RF line (402) and a further ground electrode (404) and so as to scale the RF capacitance of the cell without impacting the mechanical performance of the MEMS cells. Each cell has the same control capacitance irrespective of the RF capacitance. This allows each cell to use the same isolation resistor required for RF operation and thus each cell has the same parasitic capacitance. This allows the CMOS control circuit to be optimized and the dynamic performance of the cells to be matched.

Abstract: The present invention generally relates to a method of fabricating a MEMS device. In the MEMS device, a movable plate is disposed within a cavity such that the movable plate is movable within the cavity. To form the cavity, sacrificial material may be deposited and then the material of the movable plate is deposited thereover. The sacrificial material is removed to free the mov able plate to move within the cavity. The sacrificial material, once deposited, may not be sufficiently planar because the height difference between the lowest point and the highest point of the sacrificial material may be quite high. To ensure the movable plate is sufficiently planar, the planarity of the sacrificial material should be maximized. To maximize the surface planarity of the sacrificial material, the sacrificial material may be deposited and then conductive heated to permit the sacrificial material to reflow and thus, be planarized.

Abstract: The present invention generally relates to a DVC having a charge-pump coupled to a MEMS device. The charge-pump is designed to control the output voltage delivered to the electrodes, such as the pull-in electrode or the pull-off electrode, that move the switching element within the MEMS device between locations spaced far from and disposed closely to the RF electrode.

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.

Abstract: The present invention generally relates to methods for increasing the lifetime of MEMS devices by reducing the number of movements of a switching element in the MEMS device. Rather than returning to a ground state between cycles, the switching element can remain in the same state if both cycles necessitate the same capacitance. For example, if in both a first and second cycle, the switching element of the MEMS device is in a state of high capacitance the switching element can remain in place between the first and second cycle rather than move to the ground state. Even if the polarity of the capacitance is different in successive cycles, the switching element can remain in place and the polarity can be switched. Because the switching element remains in place between cycles, the switching element, while having the same finite number of movements, should have a longer lifetime.

Abstract: The present invention generally relates to a MEMS digital variable capacitor (DVC) (900) and a method for manufacture thereof. The movable plate (938) within a MEMS DVC should have the same stress level to ensure proper operation of the MEMS DVC. To obtain the same stress level, the movable plate is decoupled from CMOS ground during fabrication. The movable plate is only electrically coupled to CMOS ground after the plate has been completely formed. The coupling occurs by using the same layer (948) that forms the pull-up electrode as the layer that electrically couples the movable plate to CMOS ground. As the same layer couples the movable plate to CMOS ground and also provides the pull-up electrode for the MEMS DVC, the deposition occurs in the same processing step. By electrically coupling the movable plate to CMOS ground after formation, the stress in each of the layers of the movable plate can be substantially identical.

Abstract: The present invention generally relates to methods for increasing the lifetime of MEMS devices by reducing the landing velocity on switching by introducing gas into the cavity surrounding the switching element of the MEMS device. The gas is introduced using ion implantation into a cavity close to the cavity housing the switching element and connected to that cavity by a channel through which the gas can flow from one cavity to the other. The implantation energy is chosen to implant many of the atoms close to the inside roof and floor of the cavity so that on annealing those atoms diffuse into the cavity. The gas provides gas damping which reduces the kinetic energy of the switching MEMS device which then should have a longer lifetime.

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.