Abstract: Diaphragm 33 is provided on a top surface of silicon substrate 32, and plate unit 39 is fixed to the top surface of silicon substrate 32 so as to cover the movable electrode film with a gap. Plate unit 39 is made of an insulating material. Fixed electrode film 40 is formed on a bottom surface of plate unit 39, and diaphragm 33 and fixed electrode film 40 constitute a capacitor. In an area around plate unit 39, a whole outer peripheral edge of the top surface of silicon substrate 32 is exposed from plate unit 39. On the top surface of the substrate 32, insulating sheet 47 made of the insulating material is formed in a part of an area exposed from plate unit 39, and electrode pad 48 electrically connected to diaphragm 33 and electrode pad 49 electrically connected to fixed electrode film 40 are provided on a top surface of insulating sheet 47.

Abstract: Diaphragm 33 is provided on a top surface of silicon substrate 32, and plate unit 39 is fixed to the top surface of silicon substrate 32 so as to cover the movable electrode film with a gap. Plate unit 39 is made of an insulating material. Fixed electrode film 40 is formed on a bottom surface of plate unit 39, and diaphragm 33 and fixed electrode film 40 constitute a capacitor. In an area around plate unit 39, a whole outer peripheral edge of the top surface of silicon substrate 32 is exposed from plate unit 39. On the top surface of the substrate 32, insulating sheet 47 made of the insulating material is formed in a part of an area exposed from plate unit 39, and electrode pad 48 electrically connected to diaphragm 33 and electrode pad 49 electrically connected to fixed electrode film 40 are provided on a top surface of insulating sheet 47.