Abstract
This study proposes sensitivity improvement for MEMS piezoelectric microphone to increase signal to noise ratio. Using finite element analysis and lumped element modal design the microphone structure. And piezoelectric microphone devices were fabricated on lead zirconate titanate (PZT) material and Silicon-on-Insulator (SOI) process. Additionally, charge amplifier circuit increase output signal to detect. After fabrication, measuring the performance of designed microphone and comparing with typical type microphone to verify the feasibility of design. Measurement results show a flat acoustic response between 213Hz~20kHz. The sensitivity of microphone is -25dB (ref. 1V/1Pa) and signal to noise ratio is 65.16dB at 1 kHz which is higher than typical type microphone. Last, the sensitivity variation is about 20% by temperature increasing at ΔT= 60°C.