Piezoelectric microphone

Abstract

The present invention discloses a piezoelectric microphone. The piezoelectric microphone comprises a substrate having a cavity-backed, and a piezoelectric film connected to the upper side of the substrate via an insulating layer. A position on the piezoelectric film, which is located at the inner side of a junction of the piezoelectric film and the substrate, is provided with a plurality of hollowed-out holes. The hollowed-out holes in the piezoelectric film are at least partly overlapped with the substrate. A gap is provided between the substrate and the position, where the hollowed-out holes are located, on the piezoelectric film. The gap and the hollowed-out holes a together form a channel. Compared with the traditional hollowed-out structure, the gap of the present invention can hinder the sound from directly spreading via the hollowed-out holes, thereby greatly reducing the amount of leakage of low-and-intermediate frequency signals of the piezoelectric microphone and improving the performance of the piezoelectric microphone. In addition, the gap can also effectively prevent a chip from being damaged by the invasion of dust, particles and water.

Dependencies are inferred from the claim text.