ACOUSTIC SENSOR

• Main Authors: OKUGAWA AKIHIRO, MOMOTANI KOJI, KASAI TAKASHI
• Format: Patent
• Language: English; Japanese
• Published: 08.08.2016
• Subjects: DEAF-AID SETS; ELECTRIC COMMUNICATION TECHNIQUE; ELECTRICITY; LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKEACOUSTIC ELECTROMECHANICAL TRANSDUCERS; PUBLIC ADDRESS SYSTEMS

PROBLEM TO BE SOLVED: To improve impulse resistance performances of a vibration electrode film and a back plate while suppressing a stress that may be generated in each of parts.SOLUTION: An acoustic sensor comprises: a back plate formed from a stationary plate that is disposed oppositely to a front face of a semiconductor substrate and a stationary electrode film that is provided in the stationary plate; and a vibration electrode film that is disposed oppositely to the back plate via an air gap. The acoustic sensor detects acoustic vibrations by converting the acoustic vibrations into a change in electrostatic capacitance between the vibration electrode film and the stationary electrode film. The vibration electrode film includes a tabular vibration part that is induced by a sound pressure and vibrated, and is fixed to the back plate by fixing means formed from one or more fixing parts at least partially including a tip fixing part that is provided at the tip of a beam protruding from an edge of the vibration part. An edge of the back plate is formed so as to surround a part of a periphery of at least the tip fixing part.SELECTED DRAWING: Figure 3 【課題】本発明は、各部に生ずる応力を抑制しながら振動電極膜およびバックプレートの耐衝撃性能を改善することを解決課題とする。【解決手段】半導体基板の表面に対向するように配設された固定板と該固定板に設けられた固定電極膜からなるバックプレートと、前記バックプレートと空隙を介して対向するように配設された振動電極膜と、を備え、音響振動を前記振動電極膜と前記固定電極膜の間の静電容量の変化に変換して検出する音響センサにおいて、前記振動電極膜は、音圧に感応して振動する板状の振動部を有し、前記振動部の縁から突き出る梁の突端に設けられた突端固定部を少なくとも一部に有する一又は複数の固定部からなる固定手段によって前記バックプレートに固定されており、前記バックプレートの縁は、少なくとも前記突端固定部の周囲の一部を取り囲むように形成されていることを特徴とする。【選択図】図３