Robust microelectromechanical switch

A microelectromechanical (MEMS) switch, comprising:

• a substrate,
• a signal input line formed on the substrate,
• a signal output line formed on the substrate,
• a deformable conducting membrane, electrically connected to the signal output line, the deformable conducting membrane being suspended into a plane parallel to the plane of the substrate by anchors arranged on the substrate, the deformable conducting membrane comprising a contact dimple facing the signal input line such that, in a non-deformed state of the deformable conducting membrane, the contact dimple is not in contact with the signal input line and, in a deformed state of the deformable conducting membrane, the contact dimple is in contact with the signal input line for transmitting a signal from the signal input line to the signal output line,
• an actuation electrode formed on the substrate below the deformable conducting membrane, the actuation electrode being intended to deform the deformable conducting membrane for making an electrical contact between the contact dimple of the deformable conducting membrane and the signal input line,
• wherein:
• the deformable conducting membrane comprises a planar round shape, the anchors being arranged at its periphery so as to concentrate a lower stiffness in the central region of the deformable conducting membrane, with a radial opening forming an acute angle in the direction of the signal input line narrowing from the periphery towards the center of the deformable conducting membrane, the contact dimple being formed in the central region of the deformable conducting membrane such that the end of the signal input line is opposite the contact dimple,
• the actuation electrode comprises the same shape as the deformable conducting membrane, surrounding on the substrate the end of the signal input line, and
• the gap between the lower surface of the deformable conducting membrane, facing the actuation electrode, and the actuation electrode is an airgap only.