A micro-electro-mechanical device formed in a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region above the first buried cavity; and a second buried cavity extending in the sensitive region. A decoupling trench extends from a first face of the monolithic body as far as the first buried cavity and laterally surrounds the second buried cavity. The decoupling trench separates the sensitive region from a peripheral portion of the monolithic body.

A differential pressure detection element includes: a support portion having an opening; a cantilever portion supported in a cantilever manner by the support portion so as to protrude into the opening; a diffusion layer including a piezoresistive portion provided at a fixed end of the cantilever portion; a pair of wiring portions electrically connected to the diffusion layer; a first insulating layer covering the diffusion layer; and a second insulating layer laid on the first insulating layer. A linear expansion coefficient of the first insulating layer is smaller than a linear expansion coefficient of a material of which the cantilever portion is composed, and a linear expansion coefficient of the second insulating layer is larger than the linear expansion coefficient of the first insulating layer.

A micro-electro-mechanical device formed in a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region above the first buried cavity; and a second buried cavity extending in the sensitive region. A decoupling trench extends from a first face of the monolithic body as far as the first buried cavity and laterally surrounds the second buried cavity. The decoupling trench separates the sensitive region from a peripheral portion of the monolithic body.

A differential pressure detection element includes: a support portion having an opening; a cantilever portion supported in a cantilever manner by the support portion so as to protrude into the opening; a diffusion layer including a piezoresistive portion provided at a fixed end of the cantilever portion; a pair of wiring portions electrically connected to the diffusion layer; a first insulating layer covering the diffusion layer; and a second insulating layer laid on the first insulating layer. A linear expansion coefficient of the first insulating layer is smaller than a linear expansion coefficient of a material of which the cantilever portion is composed, and a linear expansion coefficient of the second insulating layer is larger than the linear expansion coefficient of the first insulating layer.

Processes for fabricating capacitive micromachined ultrasonic transducers (CMUTs) are described, as are CMUTs of various doping configurations. An insulating layer separating conductive layers of a CMUT may be formed by forming the layer on a lightly doped epitaxial semiconductor layer. Dopants may be diffused from a semiconductor substrate into the epitaxial semiconductor layer, without diffusing into the insulating layer. CMUTs with different configurations of N-type and P-type doping are also described.

A micro-electro-mechanical device formed in a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region above the first buried cavity; and a second buried cavity extending in the sensitive region. A decoupling trench extends from a first face of the monolithic body as far as the first buried cavity and laterally surrounds the second buried cavity. The decoupling trench separates the sensitive region from a peripheral portion of the monolithic body.

A microelectronic device includes a copper structure over an electronic component. The copper structure includes copper having an average grain size greater than 1 micron. The copper structure has a corrosion barrier, which includes primarily cuprous oxide, directly on the copper. The corrosion barrier is exposed at an exterior surface. The microelectronic device is formed by plating copper over a substrate of the microelectronic device. The copper structure with the corrosion barrier is annealed at a temperature of 125 C. to 200 C. in a non-reducing ambient.

A micro-electro-mechanical device formed in a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region above the first buried cavity; and a second buried cavity extending in the sensitive region. A decoupling trench extends from a first face of the monolithic body as far as the first buried cavity and laterally surrounds the second buried cavity. The decoupling trench separates the sensitive region from a peripheral portion of the monolithic body.

A micro-electro-mechanical device formed in a monolithic body of semiconductor material accommodating a first buried cavity; a sensitive region above the first buried cavity; and a second buried cavity extending in the sensitive region. A decoupling trench extends from a first face of the monolithic body as far as the first buried cavity and laterally surrounds the second buried cavity. The decoupling trench separates the sensitive region from a peripheral portion of the monolithic body.

A semiconductor device includes a first silicon layer with first and second regions of substantially different dopant concentration and a resonant MEMS member formed in the first region. A piezoelectric layer is disposed over the resonant MEMS member and conductive material is disposed over the piezoelectric layer and patterned to form first and second electrodes.