Abstract: MEMS structure, comprising: a semiconductor body; a cavity buried in the semiconductor body; a membrane suspended on the cavity; and at least one antistiction bump completely contained in the cavity with the function of preventing the side of the membrane internal to the cavity from sticking to the opposite side, which delimits the cavity downwardly.

Abstract: MEMS device formed in a semiconductor body which is monolithic and has a first and a second main surface. A buried cavity extends into the semiconductor body below and at a distance from the first main surface. A diaphragm extends between the buried cavity and the first main surface of the semiconductor body and has a buried face facing the buried cavity. A diaphragm insulating layer extends on the buried face of the diaphragm and a lateral insulating region extends into the semiconductor body along a closed line, between the first main surface and the diaphragm insulating layer, above the buried cavity. The lateral insulating region laterally delimits the diaphragm and forms, with the diaphragm insulating layer, a diaphragm insulating region which delimits the diaphragm and electrically insulates it from the rest of the wafer.

Abstract: A bottom semiconductor region is formed to include a main sub-region, extending through a bottom dielectric region that coats a semiconductor wafer, and a secondary sub-region which coats the bottom dielectric region and surrounds the main sub-region. First and second top cavities are formed through the wafer, delimiting a fixed body and a patterned structure that includes a central portion which contacts the main sub-region, and deformable portions in contact with the bottom dielectric region. A bottom cavity is formed through the bottom semiconductor region, as far as the bottom dielectric region, the bottom cavity laterally delimiting a stiffening region including the main sub-region and leaving exposed parts of the bottom dielectric region that contact the deformable portions and parts of the bottom dielectric region that delimit the first and second top cavities. The parts left exposed by the bottom cavity are selectively removed.

Abstract: A valve module includes a semiconductor body, cavities in the semiconductor body separated from each other by a distance, a cantilever structure suspended over each cavity to enable at least partial closing of the cavity, and a piezoelectric actuator for each cantilever structure. The piezoelectric actuator is configured for use to cause a positive bending of the respective cantilever structure and so modulate a rate of air flow through the valve module.

Abstract: A bottom semiconductor region is formed to include a main sub-region, extending through a bottom dielectric region that coats a semiconductor wafer, and a secondary sub-region which coats the bottom dielectric region and surrounds the main sub-region. First and second top cavities are formed through the wafer, delimiting a fixed body and a patterned structure that includes a central portion which contacts the main sub-region, and deformable portions in contact with the bottom dielectric region. A bottom cavity is formed through the bottom semiconductor region, as far as the bottom dielectric region, the bottom cavity laterally delimiting a stiffening region including the main sub-region and leaving exposed parts of the bottom dielectric region that contact the deformable portions and parts of the bottom dielectric region that delimit the first and second top cavities. The parts left exposed by the bottom cavity are selectively removed.

Abstract: A MEMS acoustic transducer provided with: a substrate of semiconductor material, having a back surface and a front surface opposite with respect to a vertical direction; a first cavity formed within the substrate, which extends from the back surface to the front surface; a membrane which is arranged at the upper surface, suspended above the first cavity and anchored along a perimeter thereof to the substrate; and a combfingered electrode arrangement including a number of mobile electrodes coupled to the membrane and a number of fixed electrodes coupled to the substrate and facing respective mobile electrodes for forming a sensing capacitor, wherein a deformation of the membrane as a result of incident acoustic pressure waves causes a capacitive variation of the sensing capacitor. In particular, the combfingered electrode arrangement lies vertically with respect to the membrane and extends parallel thereto.

Abstract: A valve module includes a semiconductor body, cavities in the semiconductor body separated from each other by a distance, a cantilever structure suspended over each cavity to enable at least partial closing of the cavity, and a piezoelectric actuator for each cantilever structure. The piezoelectric actuator is configured for use to cause a positive bending of the respective cantilever structure and so modulate a rate of air flow through the valve module.

Abstract: A MEMS acoustic transducer provided with: a substrate of semiconductor material, having a back surface and a front surface opposite with respect to a vertical direction; a first cavity formed within the substrate, which extends from the back surface to the front surface; a membrane which is arranged at the upper surface, suspended above the first cavity and anchored along a perimeter thereof to the substrate; and a combfingered electrode arrangement including a number of mobile electrodes coupled to the membrane and a number of fixed electrodes coupled to the substrate and facing respective mobile electrodes for forming a sensing capacitor, wherein a deformation of the membrane as a result of incident acoustic pressure waves causes a capacitive variation of the sensing capacitor. In particular, the combfingered electrode arrangement lies vertically with respect to the membrane and extends parallel thereto.

Abstract: Disclosed herein is a microelectromechanical device and a process for manufacturing same. One or more embodiments may include forming a semiconductor structural layer separated from a substrate by a dielectric layer, and opening a plurality of trenches through the structural layer exposing a portion of the dielectric layer. A sacrificial portion of the dielectric layer is selectively removed through the plurality of trenches in membrane regions so as to free a corresponding portion of the structural layer to form a membrane. To close the trenches, the wafer is brought to an annealing temperature for a time interval in such a way as to cause migration of the atoms of the membrane so as to reach a minimum energy configuration.

Abstract: A process for manufacturing a micromechanical structure envisages: forming a buried cavity within a body of semiconductor material, separated from a top surface of the body by a first surface layer; and forming an access duct for fluid communication between the buried cavity and an external environment. The method envisages: forming an etching mask on the top surface at a first access area; forming a second surface layer on the top surface and on the etching mask; carrying out an etch such as to remove, in a position corresponding to the first access area, a portion of the second surface layer, and an underlying portion of the first surface layer not covered by the etching mask until the buried cavity is reached, thus forming both the first access duct and a filter element, set between the first access duct and the same buried cavity.

Abstract: A process for manufacturing a micromechanical structure envisages: forming a buried cavity within a body of semiconductor material, separated from a top surface of the body by a first surface layer; and forming an access duct for fluid communication between the buried cavity and an external environment. The method envisages: forming an etching mask on the top surface at a first access area; forming a second surface layer on the top surface and on the etching mask; carrying out an etch such as to remove, in a position corresponding to the first access area, a portion of the second surface layer, and an underlying portion of the first surface layer not covered by the etching mask until the buried cavity is reached, thus forming both the first access duct and a filter element, set between the first access duct and the same buried cavity.

Abstract: A method for manufacturing a fluid ejection device, comprising the steps of: providing a first semiconductor body having a membrane layer and a piezoelectric actuator which extends over the membrane layer; forming a cavity underneath the membrane layer to form a suspended membrane; providing a second semiconductor body; making, in the second semiconductor body, an inlet through hole configured to form a supply channel of the fluid ejection device; providing a third semiconductor body; forming a recess in the third semiconductor body; forming an outlet channel through the third semiconductor body to form an ejection nozzle of the fluid ejection device; coupling the first semiconductor body with the third semiconductor body and the first semiconductor body with the second semiconductor body in such a way that the piezoelectric actuator is completely housed in the first recess, and the second recess forms an internal chamber of the fluid ejection device.

Abstract: A method for manufacturing a fluid ejection device, comprising the steps of: providing a first semiconductor body having a membrane layer and a piezoelectric actuator which extends over the membrane layer; forming a cavity underneath the membrane layer to form a suspended membrane; providing a second semiconductor body; making, in the second semiconductor body, an inlet through hole configured to form a supply channel of the fluid ejection device; providing a third semiconductor body; forming a recess in the third semiconductor body; forming an outlet channel through the third semiconductor body to form an ejection nozzle of the fluid ejection device; coupling the first semiconductor body with the third semiconductor body and the first semiconductor body with the second semiconductor body in such a way that the piezoelectric actuator is completely housed in the first recess, and the second recess forms an internal chamber of the fluid ejection device.

Abstract: A process for manufacturing a micromechanical structure envisages: forming a buried cavity within a body of semiconductor material, separated from a top surface of the body by a first surface layer; and forming an access duct for fluid communication between the buried cavity and an external environment. The method envisages: forming an etching mask on the top surface at a first access area; forming a second surface layer on the top surface and on the etching mask; carrying out an etch such as to remove, in a position corresponding to the first access area, a portion of the second surface layer, and an underlying portion of the first surface layer not covered by the etching mask until the buried cavity is reached, thus forming both the first access duct and a filter element, set between the first access duct and the same buried cavity.

Abstract: Disclosed herein is a microelectromechanical device and a process for manufacturing same. One or more embodiments may include forming a semiconductor structural layer separated from a substrate by a dielectric layer, and opening a plurality of trenches through the structural layer exposing a portion of the dielectric layer. A sacrificial portion of the dielectric layer is selectively removed through the plurality of trenches in membrane regions so as to free a corresponding portion of the structural layer to form a membrane. To close the trenches, the wafer is brought to an annealing temperature for a time interval in such a way as to cause migration of the atoms of the membrane so as to reach a minimum energy configuration.

Abstract: A process for manufacturing a micromechanical structure envisages: forming a buried cavity within a body of semiconductor material, separated from a top surface of the body by a first surface layer; and forming an access duct for fluid communication between the buried cavity and an external environment. The method envisages: forming an etching mask on the top surface at a first access area; forming a second surface layer on the top surface and on the etching mask; carrying out an etch such as to remove, in a position corresponding to the first access area, a portion of the second surface layer, and an underlying portion of the first surface layer not covered by the etching mask until the buried cavity is reached, thus forming both the first access duct and a filter element, set between the first access duct and the same buried cavity.