Abstract: A micromechanical mirror structure includes a mirror element designed to reflect an incident light radiation and a protective structure arranged over the mirror element to provide mechanical protection for the mirror element and to increase the reflectivity of the mirror element with respect to the incident light radiation. The protective structure has a first protective layer and a second protective layer which are stacked on the mirror element. The second protective layer is arranged on the first protective layer and the first protective layer is arranged on the mirror element. The layers include a respective dielectric material and having respective refractive indexes that jointly increase the reflectivity of the mirror element in a range of wavelengths of interest.

Abstract: A micromechanical mirror structure includes a mirror element designed to reflect an incident light radiation and a protective structure arranged over the mirror element to provide mechanical protection for the mirror element and to increase the reflectivity of the mirror element with respect to the incident light radiation. The protective structure has a first protective layer and a second protective layer which are stacked on the mirror element. The second protective layer is arranged on the first protective layer and the first protective layer is arranged on the mirror element. The layers include a respective dielectric material and having respective refractive indexes that jointly increase the reflectivity of the mirror element in a range of wavelengths of interest.

Abstract: A process for manufacturing an interaction system of a microelectromechanical type for a storage medium, the interaction system provided with a supporting element and an interaction element carried by the supporting element, envisages the steps of: providing a wafer of semiconductor material having a substrate with a first type of conductivity and a top surface; forming a first interaction region having a second type of conductivity, opposite to the first type of conductivity, in a surface portion of the substrate in the proximity of the top surface; and carrying out an electrochemical etch of the substrate starting from the top surface, the etching being selective with respect to the second type of conductivity, so as to remove the surface portion of the substrate and separate the first interaction region from the substrate, thus forming the supporting element.

Abstract: A process for manufacturing an interaction system of a microelectromechanical type for a storage medium, the interaction system provided with a supporting element and an interaction element carried by the supporting element, envisages the steps of: providing a wafer of semiconductor material having a substrate with a first type of conductivity (P) and a top surface; forming a first interaction region having a second type of conductivity (N), opposite to the first type of conductivity (P), in a surface portion of the substrate in the proximity of the top surface; and carrying out an electrochemical etch of the substrate starting from the top surface, the etching being selective with respect to the second type of conductivity (N), so as to remove the surface portion of the substrate and separate the first interaction region from the substrate, thus forming the supporting element.

Abstract: An electroacoustic MEMS transducer, having a substrate of semiconductor material; a through cavity in the substrate; a back plate carried by the substrate through a plate anchoring structure, the back plate having a surface facing the through cavity; a fixed electrode, extending over the surface of the back plate; a membrane of conductive material, having a central portion facing the fixed electrode and a peripheral portion fixed to the surface of the back plate through a membrane anchoring structure; and a chamber between the membrane and the back plate, peripherally delimited by the membrane anchoring structure.

Abstract: An electroacoustic MEMS transducer, having a substrate of semiconductor material; a through cavity in the substrate; a back plate carried by the substrate through a plate anchoring structure, the back plate having a surface facing the through cavity; a fixed electrode, extending over the surface of the back plate; a membrane of conductive material, having a central portion facing the fixed electrode and a peripheral portion fixed to the surface of the back plate through a membrane anchoring structure; and a chamber between the membrane and the back plate, peripherally delimited by the membrane anchoring structure.

Abstract: A method for manufacturing a protective layer for protecting an intermediate structural layer against etching with hydrofluoric acid, the intermediate structural layer being made of a material that can be etched or damaged by hydrofluoric acid, the method comprising the steps of: forming a first layer of aluminum oxide, by atomic layer deposition, on the intermediate structural layer; performing a thermal crystallization process on the first layer of aluminum oxide to form a first intermediate protective layer; forming a second layer of aluminum oxide, by atomic layer deposition, above the first intermediate protective layer; and performing a thermal crystallization process on the second layer of aluminum oxide to form a second intermediate protective layer and thereby completing the formation of the protective layer. The method for forming the protective layer can be used, for example, during the manufacturing steps of an inertial sensor such as a gyroscope or an accelerometer.

Abstract: A method for manufacturing a protective layer for protecting an intermediate structural layer against etching with hydrofluoric acid, the intermediate structural layer being made of a material that can be etched or damaged by hydrofluoric acid, the method comprising the steps of: forming a first layer of aluminum oxide, by atomic layer deposition, on the intermediate structural layer; performing a thermal crystallization process on the first layer of aluminum oxide, forming a first intermediate protective layer; forming a second layer of aluminum oxide, by atomic layer deposition, above the first intermediate protective layer; and performing a thermal crystallization process on the second layer of aluminum oxide, forming a second intermediate protective layer and thereby completing the formation of the protective layer. The method for forming the protective layer can be used, for example, during the manufacturing steps of an inertial sensor such as a gyroscope or an accelerometer.

Abstract: A process for manufacturing an interaction system of a microelectromechanical type for a storage medium, the interaction system provided with a supporting element and an interaction element carried by the supporting element, envisages the steps of: providing a wafer of semiconductor material having a substrate with a first type of conductivity and a top surface; forming a first interaction region having a second type of conductivity, opposite to the first type of conductivity, in a surface portion of the substrate in the proximity of the top surface; and carrying out an electrochemical etch of the substrate starting from the top surface, the etching being selective with respect to the second type of conductivity, so as to remove the surface portion of the substrate and separate the first interaction region from the substrate, thus forming the supporting element.

Abstract: A MEMS device formed by a body; a cavity, extending above the body; mobile and fixed structures extending above the cavity and physically connected to the body via anchoring regions; and electrical-connection regions, extending between the body and the anchoring regions and electrically connected to the mobile and fixed structures. The electrical-connection regions are formed by a conductive multilayer including a first semiconductor material layer, a composite layer of a binary compound of the semiconductor material and of a transition metal, and a second semiconductor material layer.

Abstract: A method for manufacturing a protective layer for protecting an intermediate structural layer against etching with hydrofluoric acid, the intermediate structural layer being made of a material that can be etched or damaged by hydrofluoric acid, the method comprising the steps of: forming a first layer of aluminium oxide, by atomic layer deposition, on the intermediate structural layer; performing a thermal crystallization process on the first layer of aluminium oxide, forming a first intermediate protective layer; forming a second layer of aluminium oxide, by atomic layer deposition, above the first intermediate protective layer; and performing a thermal crystallization process on the second layer of aluminium oxide, forming a second intermediate protective layer and thereby completing the formation of the protective layer. The method for forming the protective layer can be used, for example, during the manufacturing steps of an inertial sensor such as a gyroscope or an accelerometer.

Abstract: A MEMS device formed by a body; a cavity, extending above the body; mobile and fixed structures extending above the cavity and physically connected to the body via anchoring regions; and electrical-connection regions, extending between the body and the anchoring regions and electrically connected to the mobile and fixed structures. The electrical-connection regions are formed by a conductive multilayer including a first semiconductor material layer, a composite layer of a binary compound of the semiconductor material and of a transition metal, and a second semiconductor material layer.

Abstract: A method for manufacturing a protective layer for protecting an intermediate structural layer against etching with hydrofluoric acid, the intermediate structural layer being made of a material that can be etched or damaged by hydrofluoric acid, the method comprising the steps of: forming a first layer of aluminium oxide, by atomic layer deposition, on the intermediate structural layer; performing a thermal crystallization process on the first layer of aluminium oxide, forming a first intermediate protective layer; forming a second layer of aluminium oxide, by atomic layer deposition, above the first intermediate protective layer; and performing a thermal crystallization process on the second layer of aluminium oxide, forming a second intermediate protective layer and thereby completing the formation of the protective layer. The method for forming the protective layer can be used, for example, during the manufacturing steps of an inertial sensor such as a gyroscope or an accelerometer.

Abstract: A process for manufacturing a MEMS device, wherein a bottom silicon region is formed on a substrate and on an insulating layer; a sacrificial region of dielectric is formed on the bottom region; a membrane region, of semiconductor material, is epitaxially grown on the sacrificial region; the membrane region is dug down to the sacrificial region so as to form through apertures; the side wall and the bottom of the apertures are completely coated in a conformal way with a porous material layer; at least one portion of the sacrificial region is selectively removed through the porous material layer and forms a cavity; and the apertures are filled with filling material so as to form a monolithic membrane suspended above the cavity. Other embodiments are directed to MEMS devices and pressure sensors.

Abstract: A process for manufacturing a MEMS device, wherein a bottom silicon region is formed on a substrate and on an insulating layer; a sacrificial region of dielectric is formed on the bottom region; a membrane region, of semiconductor material, is epitaxially grown on the sacrificial region; the membrane region is dug down to the sacrificial region so as to form through apertures; the side wall and the bottom of the apertures are completely coated in a conformal way with a porous material layer; at least one portion of the sacrificial region is selectively removed through the porous material layer and forms a cavity; and the apertures are filled with filling material so as to form a monolithic membrane suspended above the cavity.

Abstract: A process for manufacturing an interaction system of a microelectromechanical type for a storage medium, the interaction system provided with a supporting element and an interaction element carried by the supporting element, envisages the steps of: providing a wafer of semiconductor material having a substrate with a first type of conductivity (P) and a top surface; forming a first interaction region having a second type of conductivity (N), opposite to the first type of conductivity (P), in a surface portion of the substrate in the proximity of the top surface; and carrying out an electrochemical etch of the substrate starting from the top surface, the etching being selective with respect to the second type of conductivity (N), so as to remove the surface portion of the substrate and separate the first interaction region from the substrate, thus forming the supporting element.