Patent ID: 8505358
Filing Date: 2013-08-13
Classification: G01C,Y10T

Abstract:
1. A method for adjusting the resonant frequencies of a vibrating MEMS device comprising the steps of: patterning a surface of a structural layer used to form the vibrating MEMS device with a photoresist, the photoresist having open areas where the structural layer used to form the vibrating MEMS device should be etched; etching the structural layer used to form the vibrating MEMS device at locations corresponding to the open areas to structurally define the vibrating MEMS device; determining a first resonant frequency of the vibrating MEMS device along a first axis and a second resonant frequency of the vibrating MEMS device along a second axis; determining a first mass removal amount of the vibrating MEMS device and a first mass removal location of the vibrating MEMS device to alter the first resonant frequency and reduce a resonant frequency difference between the first resonant frequency and the second resonant frequency; removing the photoresist at the first mass removal location using laser ablation; etching the vibrating MEMS device to remove the first mass removal amount of the vibrating MEMS device at the first mass removal location of the vibrating MEMS device; determining a third resonant frequency of the vibrating MEMS device along the first axis and a fourth resonant frequency of the vibrating MEMS device along the second axis; determining a second mass removal amount of the vibrating MEMS device and a second mass removal location of the vibrating MEMS device to alter the third resonant frequency and reduce a resonant frequency difference between the third resonant frequency and the fourth resonant frequency; coating a portion of the surface of the vibrating MEMS device with a masking material; removing the masking material at the second mass removal location using laser ablation; and etching the vibrating MEMS device to remove the second mass removal amount of the vibrating MEMS device at the second mass removal location of the vibrating MEMS device.