Nano Archive

Double-chip condenser microphone for rigid backplate using DRIE and wafer bonding technology

Kwon, Hyu-sang and Lee, Kwang-Cheol (2007) Double-chip condenser microphone for rigid backplate using DRIE and wafer bonding technology. Sensors and Actuators A: Physical, 138 (1). 81 - 86.

Full text is not hosted in this archive but may be available via the Official URL, or by requesting a copy from the corresponding author.

Official URL:


A novel silicon condenser microphone with a rigid backplate has been proposed and fabricated. The backplate is fabricated on a separated wafer from the membrane to enhance acoustic characteristics, and they are combined together by gold–tin (Au/Sn) eutectic solder bonding. On a 2.5 mm × 2.5 mm, 0.5 μm thick low stress silicon nitride membrane, 2 mm × 2 mm Au/Ni/Cr membrane electrode is deposited including 3 μm thick Au/Sn layer. A 2 mm × 2 mm, 150 μm thick single crystal silicon rigid backplate has 1.8 mm × 1.8 mm backplate electrode, and an air gap, which is fabricated by bulk micromachining, and a silicon deep reactive ion etching. Slots and 50–60 μm radius circular acoustic holes to reduce air damping are also formed in the backplate chip. The fabricated microphone sensitivity is 39.8 μV Pa−1 (−88 dB re. 1 V Pa−1) at 1 kHz using 28 V polarization voltage. The microphone shows flat frequency response within 1 dB from 20 Hz at least up to 5 kHz.

Item Type:Article
Uncontrolled Keywords:Au/Sn eutectic bonding; Deep reactive ion etching; MEMS condenser microphone; Packaging; Rigid backplate; Double chip technology; Wafer bonding
Subjects:Analytical Science > Nanotechnology for sensing and actuating
ID Code:4866
Deposited By:SPI
Deposited On:24 Apr 2009 17:37
Last Modified:24 Apr 2009 17:37

Repository Staff Only: item control page