MEMS device

A micro electro mechanical system device comprising:

• a substrate that has a first principal surface and a second principal surface facing the first principal surface, and in which a cavity recessed from the first principal surface side to the second principal surface side is disposed;
• and
• a micro electro mechanical system electrode that is disposed within the cavity, and that is separated from a bottom surface of the cavity to the first principal surface side,
• the micro electro mechanical system electrode including
• a movable electrode finger extending in a first direction, and connected to the substrate so as to be movable relative to the substrate,
• a fixed electrode finger extending in the first direction, and disposed at an interval from the movable electrode finger so as to face the movable electrode finger in a second direction intersecting the first direction,
• a beam portion cantilevered by the substrate, and coupling the fixed electrode finger to the substrate, and
• an electrode portion configured to, when a voltage is applied to the electrode portion, deform the beam portion by an electrostatic force, and make an interval in the second direction between the movable electrode finger and the fixed electrode finger narrower than the interval before the deformation of the beam portion, and
• the electrode portion including
• a first electrode finger extending in the first direction, and coupled to the beam portion, and
• a second electrode finger extending in the first direction, disposed at an interval from the first electrode finger so as to face the first electrode finger in the second direction, disposed to the fixed electrode finger side with respect to the first electrode finger in the second direction, and fixed to the substrate.