A microstructure may be provided by forming a metal layer such as a molybdenum layer over a substrate. An aluminum nitride layer is formed on a top surface of the metal layer. A surface portion of the aluminum nitride layer is converted into a continuous aluminum oxide-containing layer by oxidation. A dielectric spacer layer may be formed over the continuous aluminum oxide-containing layer. Contact via cavities extending through the dielectric spacer layer, the continuous aluminum oxide containing layer, and the aluminum nitride layer and down to a respective portion of the at least one metal layer may be formed using etch processes that contain a wet etch step while suppressing formation of an undercut in the aluminum nitride layer. Contact via structures may be formed in the contact via cavities. The microstructure may include a micro-electromechanical system (MEMS) device containing a piezoelectric transducer.

A microstructure may be provided by forming a metal layer such as a molybdenum layer over a substrate. An aluminum nitride layer is formed on a top surface of the metal layer. A surface portion of the aluminum nitride layer is converted into a continuous aluminum oxide-containing layer by oxidation. A dielectric spacer layer may be formed over the continuous aluminum oxide-containing layer. Contact via cavities extending through the dielectric spacer layer, the continuous aluminum oxide containing layer, and the aluminum nitride layer and down to a respective portion of the at least one metal layer may be formed using etch processes that contain a wet etch step while suppressing formation of an undercut in the aluminum nitride layer. Contact via structures may be formed in the contact via cavities. The microstructure may include a micro-electromechanical system (MEMS) device containing a piezoelectric transducer.

An approach includes a method of fabricating a switch. The approach includes forming a first cantilevered electrode, forming a second cantilevered electrode over an electrode and operable to contact the first cantilevered electrode upon an application of a voltage to the electrode, and forming an arm on the first cantilevered electrode with an extending protrusion extending upward from an upper surface of the arm.

An approach includes a method of fabricating a switch. The approach includes forming a first cantilevered electrode over a first electrode, forming a second cantilevered electrode over a second electrode and operable to directly contact the first cantilevered electrode upon an application of a voltage to at least one of the first electrode and a second electrode, and the first cantilevered electrode includes an arm with an extending protrusion which extends upward from an upper surface of the arm.

An approach includes a method of fabricating a switch. The approach includes forming a first cantilevered electrode over a first fixed electrode, forming a second cantilevered electrode with an end that overlaps the first cantilevered electrode, forming a third cantilevered electrode operable to directly contact the first cantilevered electrode upon an application of a voltage to a second fixed electrode, and forming a hermetically sealed volume encapsulating the first fixed electrode, the second fixed electrode, the first cantilevered electrode, and the second cantilevered electrode.

An approach includes a method of fabricating a switch. The approach includes forming a first cantilevered electrode operable to directly contact a second fixed electrode upon an application of a voltage to a first fixed electrode, forming a second cantilevered electrode with an end that overlaps the first cantilevered electrode, and forming a hermetically sealed volume encapsulating the first fixed electrode, the second fixed electrode, the first cantilevered electrode, and the second cantilevered electrode.

An approach includes a method of fabricating a switch. The approach includes forming a first fixed electrode and a second fixed electrode, forming a first cantilevered electrode aligned vertically over the first fixed electrode and the second fixed electrode, and operable to directly contact the second fixed electrode upon an application of a voltage to the first fixed electrode, forming a second cantilevered electrode aligned vertically over the second fixed electrode, and which has an end that overlaps the first cantilevered electrode, and forming a hermetically sealed volume encapsulating the first fixed electrode, the second fixed electrode, the first cantilevered electrode, and the second cantilevered electrode.

MEMS switches and methods of manufacturing MEMS switches is provided. The MEMS switch having at least two cantilevered electrodes having ends which overlap and which are structured and operable to contact one another upon an application of a voltage by at least one fixed electrode.

A method for fabricating a semiconductor structure includes providing a substrate with a first surface and a second surface, wherein at least one soldering pad is formed on the first surface of the substrate. The method also includes forming at least one via to expose each soldering pad by etching the substrate from the second surface, forming a seed layer to cover the second surface of the substrate and the sidewall and the bottom surfaces of each via, and then forming a redistribution metal layer over a portion of the seed layer formed on the sidewall and the bottom surfaces of each via and the second surface of the substrate surrounding each via. The method further includes alternately performing a pre-wetting process and a chemical etching process to completely remove the portion of the seed layer not covered by the redistribution metal layer.

The present disclosure provides a CMOS structure, including a substrate, a metallization layer over the substrate, a sensing structure over the metallization layer, and a signal transmitting structure adjacent to the sensing structure. The sensing structure includes an outgassing layer over the metallization layer, a patterned outgassing barrier over the outgassing layer; and an electrode over the patterned outgassing barrier. The signal transmitting structure electrically couples the electrode and the metallization layer.