Three-dimensional (3D) micro-scale shells are presented with openings of various sizes and geometries on the surface. The shell consist of a suspended ring-shaped resonator, multiple support beams, a support post, and a cap region that connects the support beams to the support post. Shells with openings of various sizes and geometries allow the creation of micro electromechanical systems (MEMS) sensors and actuators with a wide range of engineered mechanical and electrical properties. The openings on the shell surface can, for example, control the mechanical quality factor (Q) and resonance frequencies of the shell when the shell is used as a suspended proof mass of a mechanical resonator of a vibratory gyroscope. The shells can also serve as mechanical supporting layers and/or an electrode connection layer for MEMS actuators and sensors that use 3D shells as proof masses.

Methods and systems for reducing stiction through roughening the surface and reducing the contact area in MEMS devices are disclosed. A method includes fabricating bumpstops on a surface of a MEMS device substrate to reduce stiction. Another method is directed to applying roughening etchant to a surface of a silicon substrate to enhance roughness after cavity etch and before removal of hardmask. Another embodiment described herein is directed to a method to reduce contact area between proof mass and UCAV (“upper cavity”) substrate surface with minimal impact on the cavity volume by introducing a shallow etch process step and maintaining high pressure in accelerometer cavity. Another method is described as to increasing the surface roughness of a UCAV substrate surface by depositing a rough layer (e.g. polysilicon) on the surface of the substrate and etching back the rough layer to transfer the roughness.

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.

The present invention provides a method for preparing a micro-cavity array surface with an inclined smooth bottom surface based on an air molding method. The method includes: preparing a micro-cavity array surface; preparing an auxiliary microstructure polymer template, and performing plasma treatment on the auxiliary microstructure polymer template; uniformly spreading a layer of a liquid polymer film to be formed on the auxiliary microstructure polymer template subjected to the plasma treatment; placing a gap bead in an empty position on the micro-cavity array surface; placing the auxiliary microstructure polymer template spread with the liquid polymer film on the gap bead on the micro-cavity array surface, maintaining this state, and feeding the auxiliary microstructure polymer template into a vacuum drying oven; and heating and solidifying the liquid polymer film, and separating the micro-cavity array surface to obtain the micro-cavity array surface with the inclined smooth bottom surface.

A method includes obtaining an active device layer. The active device layer has a first surface with one or more active feature areas. First portions of the active feature areas are exposed, and second portions of the active feature areas are covered by an insulating layer. A conformal overcoat layer is formed on the first surface. A base of a microelectromechanical systems (MEMS) device layer is formed on the conformal overcoat layer. The MEMS device layer is spatially segregated from the active feature areas by removing portions of the base of the MEMS device layer in one or more antiparasitic regions (APRs) that correspond to the active feature areas. Metal MEMS features are formed on the base of the MEMS device layer. Selected portions of the active feature areas are exposed removing portions of the conformal overcoat layer that overlay the active feature areas.

The method comprises contacting a silicon substrate with a silver salt and an acid for a time effective to produce spikes having a first end disposed on the silicon substrate and a second end extending away from the silicon substrate. The spikes have a second end diameter of about 10 nm to about 200 nm, a height of about 100 nm to 10 micrometers, and a density of about 10 to 100 per square microns. The nanostructures provide antimicrobial properties and can be transferred to the surface of various materials such as polymers.

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 conductors. 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.

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.

The present invention provides a method for preparing a micro-cavity array surface with an inclined smooth bottom surface based on an air molding method. The method includes: preparing a micro-cavity array surface; preparing an auxiliary microstructure polymer template, and performing plasma treatment on the auxiliary microstructure polymer template; uniformly spreading a layer of a liquid polymer film to be formed on the auxiliary microstructure polymer template subjected to the plasma treatment; placing a gap bead in an empty position on the micro-cavity array surface; placing the auxiliary microstructure polymer template spread with the liquid polymer film on the gap bead on the micro-cavity array surface, maintaining this state, and feeding the auxiliary microstructure polymer template into a vacuum drying oven; and heating and solidifying the liquid polymer film, and separating the micro-cavity array surface to obtain the micro-cavity array surface with the inclined smooth bottom surface.