| 摘要 |
In the present invention, a through-hole (33) is provided, which is open above and below, upon a silicon substrate (32). A diaphragm (35) is disposed above the through-hole (33) of the silicon substrate (32). The periphery of the diaphragm (35) faces the upper surface of the silicon substrate (32) with a gap open therebetween, and between the periphery lower surface of the diaphragm (35) and the top surface of the silicon substrate (32) is formed a vent hole (36) for passing acoustic vibration. Above the diaphragm (35) is provided a fixed electrode film (46) across an air gap. Upon areas overlapping the periphery of the diaphragm (35) of the top surface of the silicon substrate (32) are provided air escape portions (34) for which at least a respective portion is configured by a slope surface. For the air escape portions (34), a cross-sectional area which is parallel to the top surface of the silicon substrate (32) in at least a portion thereof is formed so as to become smaller toward below from the top surface aperture of the air escape portions (34). The slope surfaces of the air escape portions (34) are configured by the densest surfaces of the silicon substrate (32). |
