A CMOS compatible thermally excited silicon oxide beam resonator with aluminum mirror

The authors designed, manufactured, and characterized a thermally excited silicon oxide beam resonator based on CMOS technology with subsequent micromachining. Besides optical measurements of the resonance frequencies and vibration amplitudes, the acoustic transmission efficiency of the device in air was investigated. At a fundamental resonance of 10.35 kHz, a vibration amplitude of 2 mu m at the tip of the beam with a dynamic heating power P/sub dyn1/=2.5 mW and a sound pressure of 2.8 mPa with P/sub dyn1/=7.4 mW at 4 mm distance from the chip were measured. The oxide beam was simulated with the finite-element program ANSYS to obtain the shape of the resonant modes.<>