Qorvo US, Inc.

Cavendish Kinetics Limited

Shibajyoti Ghosh Dastider

Mickael Renault

Jacques Marcel Muyango

Robertus Petrus Van Kampen

Richard Lee Knipe

James D Huffman

Lance W Barron

Willibrordus G M Van Den Hoek

James Douglas Huffman

Jaques Marcel Muyango

A method of manufacturing a MEMS device. The MEMS device has a cavity in which a beam will move to change the capacitance of the device. After most of the device build-up has occurred, sacrificial material is removed to free the beam within the MEMS device cavity. Thereafter, exposed ruthenium contacts are exposed to fluorine to either: dope exposed ruthenium and reduce surface adhesive forces, form fluorinated Self-Assembled Monolayers on the exposed ruthenium surfaces, deposit a nanometer passivating film on exposed ruthenium, or alter surface roughness of the ruthenium. Due to the fluorine treatment, low resistance, durable contacts are present, and the contacts are less susceptible to stiction events.

Anti-stiction enhancement of ruthenium contact

A method of manufacturing a MEMS device, wherein the MEMS device has a cavity in which a beam will move to change the capacitance of the device. After most of the device build-up has occurred, sacrificial material is removed to free the beam within the MEMS device cavity. Thereafter, exposed ruthenium contacts are etched back with an etchant comprising chlorine to remove the top surface of both the top and bottom contacts. Due to this etch back process, low contact resistance can be achieved with less susceptibility to stiction events. Stiction performance can be further improved by conditioning the ruthenium contacts in a fluorine based plasma. The fluorine based plasma process, or fluorine treatment, can be performed prior to or after etch-back process of the ruthenium contacts.

MEMS device having decreased contact resistance

Methods of forming a microelectromechanical device are disclosed. In some embodiments, a first layer is deposited on a backplane having at least two electrodes. One or more electrical contacts over the first layer are formed. Forming the one or more electrical contacts includes: depositing a first ruthenium layer over the first layer, depositing a titanium nitride layer over the first ruthenium layer, depositing a second ruthenium layer over the titanium nitride layer, etching the second ruthenium layer with a first etchant, etching the titanium nitride layer with a second etchant different than the first etchant; and etching the first ruthenium layer with the first etchant. Additionally, a beam is formed above one or more electrical contacts, the beam being spaced from the one or more electrical contacts and a top electrode is formed above the beam. A seal layer above the beam to enclose the beam in a cavity.

MEMS device having uniform contacts

A method of forming a microelectromechanical device wherein a beam of the microelectromechanical device may deviate from a resting to an engaged or disengaged position through electrical biasing. The microelectromechanical device comprises a beam disposed above a first RF electrode and a second RF electrode. The microelectromechanical device further comprises one or more electrical contacts disposed below the beam. The one or more electrical contacts comprise a first layer of ruthenium disposed over an oxide layer, a titanium nitride layer disposed on the first layer of ruthenium, and a second layer of ruthenium disposed on the titanium nitride layer.

A method of forming a microelectromechanical device wherein a beam of the microelectromechanical device may deviate from a resting to an engaged or disengaged position through electrical biasing. The microelectromechanical device comprises a beam disposed above a first RF conductor and a second RF conductor. The microelectromechanical device further comprises at least a center stack, a first RF stack, a second RF stack, a first stack formed on a first base layer, and a second stack formed on a second base layer, each stack disposed between the beam and the first and second RF conductors. The beam is configured to deflect downward to first contact the first stack formed on the first base layer and the second stack formed on the second base layer simultaneously or the center stack, before contacting the first RF stack and the second RF stack simultaneously.

Method of forming a flexible MEMS device

The present invention generally relates to a mechanism for making a MEMS switch that has a robust RF-contact by avoiding currents to run through a thin sidewall in a via from the RF-contact to the underlying RF-electrode.

Contact in RF-switch

A MEMS switch contains an RF electrode, pull-down electrodesand anchor electrodeslocated on a substrate. A plurality of islandsare provided in the pull-down electrode and electrically isolated therefrom. On top of the RF electrode is the RF contactto which the MEMS-bridgeforms an ohmic contact in the pulled-down state. The pull-down electrodesare covered with a dielectric layerto avoid a short-circuit between the bridge and the pull-down electrode. Contact stoppersare disposed on the dielectric layerat locations corresponding to the islands, and the resulting gap between the bridge and the dielectric layer in the pulled-down state reduces dielectric charging. In alternative embodiments, the contact stoppers are provide within the dielectric layeror disposed on the islands themselves and under the dielectric layer. The switch provides good controllability of the contact resistance of MEMS switches over a wide voltage operating range.

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Rocklin, CA, United States of America

Shibajyoti Ghosh Dastider