ACOUSTIC TRANSDUCER, AND MICROPHONE USING THE ACOUSTIC TRANSDUCER

摘要

An acoustic sensor (11) includes: a semiconductor substrate; a vibrating membrane (22), formed above the semiconductor substrate, which includes a vibrating electrode (22a); and a fixed membrane (23), formed on an upper surface of the semiconductor substrate, which includes a fixed electrode (23a), the acoustic sensor (11) detecting an acoustic wave according to a change in capacitance between the vibrating electrode (22a) and the fixed electrode (23a). The fixed membrane (23) has a plurality of sound hole portions (32) formed therein in order to allow the acoustic wave to reach the vibrating membrane (22) from outside, and the fixed electrode (23a) is formed so that a boundary of an edge portion (40) of the fixed electrode (23a) does not intersect the sound hole portions (32).