A device includes a substrate comprising a first standoff, a second standoff, a third standoff, a first cavity, a second cavity, and a bonding material covering a portion of the first, the second, and the third standoff. The first cavity is positioned between the first and the second standoffs, and the second cavity is positioned between the second and the third standoffs. The first cavity comprises a first cavity region and a second cavity region separated by a portion of the substrate extruding thereto, and wherein a depth associated with the first cavity region is greater than a depth associated with the second cavity. A surface of the first cavity is covered with a getter material.

The present disclosure relates to a microelectromechanical systems (MEMS) apparatus. The MEMS apparatus includes a base substrate and a conductive routing layer disposed over the base substrate. A bump feature is disposed directly over the conductive routing layer. Opposing outermost sidewalls of the bump feature are laterally between outermost sidewalls of the conductive routing layer. A MEMS substrate is bonded to the base substrate and includes a MEMS device directly over the bump feature. An anti-stiction layer is arranged on one or more of the bump feature and the MEMS device.

A method for manufacturing a MEMS structure is provided. The method includes providing a MEMS substrate having a first surface, forming a first buffer layer on the first surface of the MEMS substrate, and forming a first roughening layer on the first buffer layer. Also, a MEMS structure is provided. The MEMS structure includes a MEMS substrate, a first buffer layer, a first roughening layer, and a CMOS substrate. The MEMS substrate has a first surface and a pillar is on the first surface. The first buffer layer is on the first surface. The first roughening layer is on the first buffer layer. The CMOS substrate has a second surface and is bonded to the MEMS substrate via the pillar. Moreover, an air gap is between the first roughening layer and the second surface of the CMOS substrate.

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 micro-electromechanical-system (MEMS) device may be formed to include an anti-stiction polysilicon layer on one or more moveable MEMS structures of a device wafer of the MEMS device to reduce, minimize, and/or eliminate stiction between the moveable MEMS structures and other components or structures of the MEMS device. The anti-stiction polysilicon layer may be formed such that a surface roughness of the anti-stiction polysilicon layer is greater than the surface roughness of a bonding polysilicon layer on the surfaces of the device wafer that are to be bonded to a circuitry wafer of the MEMS device. The higher surface roughness of the anti-stiction polysilicon layer may reduce the surface area of the bottom of the moveable MEMS structures, which may reduce the likelihood that the one or more moveable MEMS structures will become stuck to the other components or structures.

The present disclosure relates to a microelectromechanical systems (MEMS) package featuring a flat plate having a raised edge around its perimeter serving as an anti-stiction device, and an associated method of formation. A CMOS IC is provided having a dielectric structure surrounding a plurality of conductive interconnect layers disposed over a CMOS substrate. A MEMS IC is bonded to the dielectric structure such that it forms a cavity with a lowered central portion the dielectric structure, and the MEMS IC includes a movable mass that is arranged within the cavity. The CMOS IC includes an anti-stiction plate disposed under the movable mass. The anti-stiction plate is made of a conductive material and has a raised edge surrounding at least a part of a perimeter of a substantially planar upper surface.

A surface of a cavity of a MEMS device that is rough to reduce stiction. In some embodiments, the average roughness (Ra) of the surface is 5 nm or greater. In some embodiments, the rough surface is formed by forming one or more layers of a rough oxidizable material, then oxidizing the material to form an oxide layer with a rough surface. Another layer is formed over the oxide layer with the rough surface, wherein the roughness of the oxide layer is transferred to the another layer.

A microelectromechanical systems (MEMS) package with roughness for high quality anti-stiction is provided. A device substrate is arranged over a support device. The device substrate comprises a movable element with a lower surface that is rough and that is arranged within a cavity. A dielectric layer is arranged between the support device and the device substrate. The dielectric layer laterally encloses the cavity. An anti-stiction layer lines the lower surface of the movable element. A method for manufacturing the MEMS package is also provided.

A mechanism for reducing stiction in a MEMS device by decreasing surface area between two surfaces that can come into close contact is provided. Reduction in contact surface area is achieved by increasing surface roughness of one or both of the surfaces. The increased roughness is provided by forming a micro-masking layer on a sacrificial layer used in formation of the MEMS device, and then etching the surface of the sacrificial layer. The micro-masking layer can be formed using nanoclusters. When a next portion of the MEMS device is formed on the sacrificial layer, this portion will take on the roughness characteristics imparted on the sacrificial layer by the etch process. The rougher surface decreases the surface area available for contact in the MEMS device and, in turn, decreases the area through which stiction can be imparted.

The present disclosure provides a method for manufacturing a CMOS-MEMS structure. The method includes etching a cavity on a first surface of a cap substrate; bonding the first surface of the cap substrate with a sensing substrate; thinning a second surface of the sensing substrate, the second surface being opposite to a third surface of the sensing substrate bonded to the cap substrate; etching the second surface of the sensing substrate; patterning a portion of the second surface of the sensing substrate to form a plurality of bonding regions; depositing an eutectic metal layer on the plurality of bonding regions; etching a portion of the sensing substrate under the cavity to form a movable element; and bonding the sensing substrate to a CMOS substrate through the eutectic metal layer.