Design and implementation of a novel CMOS MEMS condenser microphone with corrugated diaphragm

This study reports a CMOS-MEMS condenser microphone implemented using the standard thin films stacking of 0.35µm UMC CMOS 3.3/5.0V logic process, and followed by post-CMOS micromachining steps without introducing any special materials. The corrugated diaphragm for microphone is designed and implemented using the metal layer to reduce the influence of thin film residual stresses. Moreover, silicon substrate is employed to increase the stiffness of back-plate. Measurements show the sensitivity of microphone is −42±3dBV/Pa at 1kHz under 6V pumping voltage, the frequency response is 100Hz–10kHz, and the S/N ratio >55dB. Table1 summarizes detail specifications.