ACOUSTIC TRANSDUCER, AND MICROPHONE USING THE ACOUSTIC TRANSDUCER

摘要

In an acoustic sensor (11), a vibrating membrane (22) and a fixed membrane (23) are formed on the upper face of a semiconductor substrate, and an acoustic wave is detected by the change of capacitance between a vibration electrode (22a) of the vibrating membrane (22) and a fixed electrode (23a) of the fixed membrane (23). The fixed membrane(23) is provided with a plurality of sound holes (32) for delivering the acoustic wave from the outside to the vibrating membrane (22), and the fixed electrode (23a) is formed so that the boundary of the edge portion (40) does not intersect the sound holes (32).