Stmicroelectronics S.r.l.

Stmicroelectronics Gmbh

Stmicroelectronics International N.v.

Carlo Luigi Prelini

Domenico Giusti

Marco Ferrera

Mauro Cattaneo

Fabio Quaglia

Simon Dodd

Roberto Carminati

Massimiliano Merli

Lorenzo Tentori

Lorenzo Colombo

Dino Faralli

Andrea Nomellini

Alessandra Sciutti

Paola Zuliani

Sonia Costantini

Luca Seghizzi

Nicolo′ Boni

Carla Maria Lazzari

Irene Martini

Davide Assanelli

Paolo Ferrarini

Gianluigi Confalonieri

Annalisa Gilardini

Nicolò Boni

The present disclosure is directed to transducer assemblies or device in which one or more buried cavities are present within a substrate and define or form one or more membranes along a surface of the substrate. One or more piezoelectric actuators are formed on the one or more membranes and the one or more piezoelectric actuators drive the membranes at an operating frequency with an operating bandwidth of the transducer assemblies. Each of the one or more membranes is anchored at respective portions to a main body portion of the substrate to provide robust and strong anchoring of each of the one or more membranes to push unwanted flexure modes outside the operating bandwidth of the transducer assemblies.

Transducer assembly with buried cavities and method of manufacturing the same

A piezoelectric microelectromechanical structure is provided with a piezoelectric stack having a main extension in a horizontal plane and a variable section in a plane transverse to the horizontal plane. The stack is formed by a bottom-electrode region, a piezoelectric material region arranged on the bottom-electrode region, and a top-electrode region arranged on the piezoelectric material region. The piezoelectric material region has, as a result of the variable section, a first thickness along a vertical axis transverse to the horizontal plane at a first area, and a second thickness along the same vertical axis at a second area. The second thickness is smaller than the first thickness. The structure at the first and second areas can form piezoelectric detector and a piezoelectric actuator, respectively.

Process for manufacturing a thin-film piezoelectric microelectromechanical structure having improved electrical characteristics

A MEMS device having a body with a first and a second surface, a first portion and a second portion. The MEMS device further has a cavity extending in the body from the second surface; a deformable portion between the first surface and the cavity; and a piezoelectric actuator arranged on the first surface, on the deformable portion. The deformable portion has a first region with a first thickness and a second region with a second thickness greater than the first thickness. The second region is adjacent to the first region and to the first portion of the body.

Piezoelectric mems device with a suspended membrane having high mechanical shock resistance and manufacturing process thereof

The MEMS actuator is formed by a body, which surrounds a cavity and by a deformable structure, which is suspended on the cavity and is formed by a movable portion and by a plurality of deformable elements. The deformable elements are arranged consecutively to each other, connect the movable portion to the body and are each subject to a deformation. The MEMS actuator further comprises at least one plurality of actuation structures, which are supported by the deformable elements and are configured to cause a translation of the movable portion greater than the deformation of each deformable element. The actuation structures each have a respective first piezoelectric region.

Piezoelectric actuator provided with a deformable structure having improved mechanical properties and fabrication method thereof

Various embodiments provide an ejection device for a fluid. The ejection device includes a first semiconductor wafer, housing, on a first side thereof, a piezoelectric actuator and an outlet channel for the fluid alongside the piezoelectric actuator; a second semiconductor wafer having, on a first side thereof, a recess and, on a second side thereof opposite to the first side, at least one inlet channel for said fluid fluidically coupled to the recess; and a dry-film coupled to a second side, opposite to the first side, of the first wafer. The first and the second wafers are coupled together so that the piezoelectric actuator and the outlet channel are set directly facing, and completely contained in, the recess that forms a reservoir for the fluid. The dry-film has an ejection nozzle.

Fluid ejection device with reduced number of components, and method for manufacturing the fluid ejection device

Piezoelectric MEMS device with a suspended membrane having high mechanical shock resistance and manufacturing process thereof

The MEMS actuator is formed by a substrate, which surrounds a cavity; by a deformable structure suspended on the cavity; by an actuation structure formed by a first piezoelectric region of a first piezoelectric material, supported by the deformable structure and configured to cause a deformation of the deformable structure; and by a detection structure formed by a second piezoelectric region of a second piezoelectric material, supported by the deformable structure and configured to detect the deformation of the deformable structure.

Piezoelectric actuator having a deformation sensor and fabrication method thereof

A method for manufacturing a device for ejecting a fluid, including the steps of: forming, in a first semiconductor wafer that houses a nozzle of the ejection device, a first structural layer; removing selective portions of the first structural layer to form a first portion of a chamber for containing the fluid; removing, in a second semiconductor wafer that houses an actuator of the ejection device, selective portions of a second structural layer to form a second portion of the chamber; and coupling together the first and second semiconductor wafers so that the first portion directly faces the second portion, thus forming the chamber. The first portion defines a part of volume of the chamber that is larger than a respective part of volume of the chamber defined by the second portion.

Method for manufacturing a fluid-ejection device with improved resonance frequency and fluid ejection velocity, and fluid-ejection device

The microfluidic device has a plurality of ejector elements. Each ejector element includes a first region, accommodating a first fluid flow channel and an actuator chamber; a second region, accommodating a fluid containment chamber; and a third region, accommodating a second fluid flow channel. The fluid containment chamber is fluidically coupled to the first and to the second fluid flow channels. The second region is formed from a membrane layer, from a membrane definition layer, mechanically coupled to the membrane layer and having a membrane definition opening, and a fluid chamber defining body, mechanically coupled to the membrane definition layer and having a chamber defining opening, with a width greater than the width of the membrane definition opening. The width of the membrane is thus defined by the width of the chamber defining opening.

Microfluidic MEMS device with piezoelectric actuation and manufacturing process thereof

Ejection device for fluid, comprising a solid body including: first semiconductor body including a chamber for containing the fluid, an ejection nozzle in fluid connection with the chamber, and an actuator operatively connected to the chamber to generate, in use, one or more pressure waves in the fluid such as to cause ejection of the fluid from the ejection nozzle; and a second semiconductor body including a channel for feeding the fluid to the chamber, coupled to the first semiconductor body, in such a way that the channel is in fluid connection with the chamber. The second semiconductor body integrates a damping cavity over which extends a damping membrane, the damping cavity and the damping membrane extending laterally to the channel for feeding the fluid.

Methods of forming and using fluid ejection devices and printheads

A micro-electro-mechanical (MEMS) actuator device includes a frame, and a first functional sub-structure positioned within the frame and mechanically coupled thereto by supporting elements. The first functional sub-structure is subdivided into first and second portions. The first portion is subdivided into first and second sub-portions separated from one another by a first through trench, and the second portion is subdivided into first and second sub-portions separated from one another by a second through trench. First and second piezo-electric structures are respectively carried by the first and second sub-portions of the first portion. Third and fourth piezo-electric structures are respectively carried by the first and second sub-portions of the second portion. A third through trench extends between the frame and the first functional sub-structure except for regions in which the supporting elements are present.

Micro-electro-mechanical actuator device of piezoelectric type and apparatus integrating the micro-electro-mechanical actuator device

A fluid ejection device, comprising: a chamber; a membrane, with a first side and a second side opposite to one another, where the first side faces the chamber; an actuator, of a piezoelectric type, which extends on the second side of the membrane and is operatively coupled to the membrane for causing, in use, a vibration of the membrane; a passivation layer, which extends only alongside, or partially on, the actuator; and a protection layer, which extends on the actuator at least in surface portions of the latter that are free from the passivation layer, and has a Young's modulus lower than the Young's modulus of the passivation layer.

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Seveso, Italy

Carlo Luigi Prelini