Abstract: A method for the formation of a region of silicon dioxide on a substrate of monocrystalline silicon. The epitaxial growth of a silicon layer, the opening of holes in the silicon layer above the silicon dioxide region, and the removal of the silicon dioxide which constitutes the region by means of chemical attack through the holes until a silicon diaphragm, attached to the substrate along the edges and separated therefrom by a space, is produced. In order to form an absolute pressure microsensor, the space has to be sealed. To do this, the method provides for the holes to have diameters smaller than the thickness of the diaphragm and to be closed by the formation of a silicon dioxide layer by vapor-phase deposition at atmospheric pressure.

Abstract: A process for manufacturing components in a multi-layer wafer, including the steps of: providing a multi-layer wafer comprising a first semiconductor material layer, a second semiconductor material layer (, and a dielectric material layer arranged between the first and the second semiconductor material layer; and removing the first semiconductor material layer initially by mechanically thinning the first semiconductor material layer, so as to form a residual conductive layer, and subsequently by chemically removing the residual conductive layer. In one application, the multi-layer wafer is bonded to a first wafer of semiconductor material, with the second semiconductor material layer facing the first wafer, after micro-electromechanical structures have been formed in the second semiconductor material layer of the multi-layer wafer.

Abstract: The method is based on the use of an etching mask comprising silicon carbide or titanium nitride for removing a sacrificial region. In case of manufacture of integrated semiconductor material structures, the following steps are performed: forming a sacrificial region of silicon oxide on a substrate of semiconductor material; growing a pseudo-epitaxial layer; forming electronic circuit components; depositing a masking layer comprising silicon carbide or titanium nitride; defining photolithographically the masking layer so as to form an etching mask containing the topography of a microstructure to be formed; with the etching mask, forming trenches in the pseudo-epitaxial layer as far as the sacrificial region so as to laterally define the microstructure; and removing the sacrificial region through the trenches.

Abstract: An angular speed sensor comprises a pair of mobile masses which are formed in an epitaxial layer and are anchored to one another and to the remainder of the device by anchorage elements. The mobile masses are symmetrical with one another, and have first mobile excitation electrodes which are intercalated with respective first fixed excitation electrodes and second mobile detection electrodes which are intercalated with second fixed detection electrodes. The first mobile and fixed excitation electrodes extend in a first direction and the second mobile and fixed detection electrodes extend in a second direction which is perpendicular to the first direction and is disposed on a single plane parallel to the surface of the device.

Abstract: An angular speed sensor comprises a pair of mobile masses which are formed in an epitaxial layer and are anchored to one another and to the remainder of the device by anchorage elements. The mobile masses are symmetrical with one another, and have first mobile excitation electrodes which are intercalated with respective first fixed excitation electrodes and second mobile detection electrodes which are intercalated with second fixed detection electrodes. The first mobile and fixed excitation electrodes extend in a first direction and the second mobile and fixed detection electrodes extend in a second direction which is perpendicular to the first direction and is disposed on a single plane parallel to the surface of the device.

Abstract: On a substrate of semiconductor material, a sacrificial region is formed and an epitaxial layer is grown; a stress release trench is formed, surrounding an area of the epitaxial layer, where an integrated electromechanical microstructure is to be formed; the wafer is then heat treated, to release residual stress. Subsequently, the stress release trench is filled with a sealing region of dielectric material, and integrated components are formed. Finally, inside the area surrounded by the sealing region, a microstructure definition trench is formed, and the sacrificial region is removed, thus obtaining an integrated microstructure with zero residual stress.

Abstract: The method is based on the use of an etching mask comprising silicon carbide or titanium nitride for removing a sacrificial region. In case of manufacture of integrated semiconductor material structures, the following steps are performed: forming a sacrificial region of silicon oxide on a substrate of semiconductor material; growing a pseudo-epitaxial layer; forming electronic circuit components; depositing a masking layer comprising silicon carbide or titanium nitride; defining photolithographically the masking layer so as to form an etching mask containing the topography of a microstructure to be formed; with the etching mask, forming trenches in the pseudo-epitaxial layer as far as the sacrificial region so as to laterally define the microstructure; and removing the sacrificial region through the trenches.

Abstract: An angular speed sensor comprises a pair of mobile masses which are formed in an epitaxial layer and are anchored to one another and to the remainder of the device by anchorage elements. The mobile masses are symmetrical with one another, and have first mobile excitation electrodes which are intercalated with respective first fixed excitation electrodes and second mobile detection electrodes which are intercalated with second fixed detection electrodes. The first mobile and fixed excitation electrodes extend in a first direction and the second mobile and fixed detection electrodes extend in a second direction which is perpendicular to the first direction and is disposed on a single plane parallel to the surface of the device.

Abstract: The method is based on the use of a silicon carbide mask for removing a sacrificial region. In case of manufacture of integrated semiconductor material structures, the following steps are performed: forming a sacrificial region of silicon oxide on a substrate of semiconductor material; growing a pseudo-epitaxial layer; forming electronic circuit components; depositing a silicon carbide layer; defining photolithographically the silicon carbon layer so as to form an etching mask containing the topography of a microstructure to be formed; with the etching mask, forming trenches in the pseudo-epitaxial layer as far as the sacrificial region so as to laterally define the microstructure; and removing the sacrificial region through the trenches.

Abstract: A sensor having high sensitivity is formed using a suspended structure with a high-density tungsten core. To manufacture it, a sacrificial layer of silicon oxide, a polycrystal silicon layer, a tungsten layer and a silicon carbide layer are deposited in succession over a single crystal silicon body. The suspended structure is defined by selectively removing the silicon carbide, tungsten and polycrystal silicon layers. Then spacers of silicon carbide are formed which cover the uncovered ends of the tungsten layer, and the sacrificial layer is then removed.

Abstract: A movable mass forming a seismic mass is formed starting from an epitaxial layer and is covered by a weighting region of tungsten which has high density. To manufacture the mass, buried conductive regions are formed in the substrate. Then, at the same time, a sacrificial region is formed in the zone where the movable mass is to be formed and oxide insulating regions are formed on the buried conductive regions so as to partially cover them. An epitaxial layer is then grown, using a nucleus region. A tungsten layer is deposited and defined and, using a silicon carbide layer as mask, the suspended structure is defined. Finally, the sacrificial region is removed, forming an air gap.

Abstract: A sensor having high sensitivity is formed using a suspended structure with a high-density tungsten core. To manufacture it, a sacrificial layer of silicon oxide, a polycrystal silicon layer, a tungsten layer and a silicon carbide layer are deposited in succession over a single crystal silicon body. The suspended structure is defined by selectively removing the silicon carbide, tungsten and polycrystal silicon layers. Then spacers of silicon carbide are formed which cover the uncovered ends of the tungsten layer, and the sacrificial layer is then removed.