US Patent 7953235 Directional silicon condenser microphone having additional back chamber

A directional silicon condenser microphone which has an additional back chamber includes a case having a front sound hole for passing through a front sound; an acoustic delay device for delaying a phase of a sound; a substrate including a chamber case, a MEMS chip having an additional back chamber formed by the chamber case, an ASIC chip for operating the MEMS chip, a conductive pattern for bonding the substrate to the case, and a rear sound hole for passing through a rear sound. The case is fixed to the substrate; and an adhesive for bonding the case and the substrate is applied to an entirety of a bonding surface of the case and the substrate.