Microelectromechanical element and a method for manufacturing it

A microelectromechanical element comprising:

• a plurality of microstructures of wafers bonded to each other, such that a gap is closed by bonding of the microstructures;
• mobile structure parts suspended to move within the closed gap;
• at least one internal electrode arranged in the gap and configured to detect or actuate movement of the mobile structure parts;
• and
• patterned regions of silicon wafer material and glass material, the regions of glass material including at least a first glass region comprising a first glass material and a second glass region comprising a second glass material,
• wherein at least one microstructure in the plurality of microstructures includes a plurality of silicon through vias, electrically isolated from each other by regions of second glass material,
• wherein the first glass material enables anodic bonding with the silicon wafer material, and
• wherein the second glass material has an alkali metal content that is less than an alkali metal content of the first glass material.