| 摘要 |
PROBLEM TO BE SOLVED: To provide an MEMS microphone, that is, an acoustic sensor which reduces noise caused by light, and is highly reliable. SOLUTION: A microphone device includes: a capacitor equipped with a vibration film as a first electrode, a dielectric film adhered to the vibration film, and a second electrode arranged oppositely to the first electrode on a semiconductor substrate; an amplifier which is connected to the first electrode of the capacitor, and amplifies a signal from the capacitor; a capacitor electrode terminal connected to the second electrode of the capacitor; a voltage supply terminal connected to the amplifier; an earth terminal; and an output terminal from the amplifier. The first and second electrodes of the capacitor are the same conductivity types as the semiconductor substrate. COPYRIGHT: (C)2010,JPO&INPIT |
