Switch, semiconductor device, and manufacturing method thereof

Abstract

It is an objective to achieve a MEMS switch which can be mounted with a CMOS circuit and has a contact point with high reliability, both mechanically and electrically. An insulator having a compatibility with a CMOS process is formed at the contact surface of a cantilever beam constituting a MEMS switch and a fixed contactopposite thereto. When the switch is used the cantilever beam is moved by applying a voltage to the pull-in electrode and the cantilever beam. After the cantilever beam makes contact with the fixed contact, a voltage exceeding the breakdown field strength of the insulator is applied to the insulator, resulting in dielectric breakdown occurring. By modifying the insulator once, the mechanical fatigue concentration point of the switch contact point is protected, and a contact point is achieved as well in which electrical signals are transmitted through the current path formed by the dielectric breakdown.