專利摘要 | A silicon dual inertial sensor made of a ( 110) silicon chip comprises at least a proof-mass, which is connected to a corresponding inner frame with a plurality of sensing resilient beams to make it easier for the proof-mass to move perpendicular to the surface of the silicon chip (defined as z-axis), and each inner frame is connected to an outer frame with a plurality of driving resilient beams, or connected to common connection beams, which are then connected to a central anchor with common resilient supporting beams to make it easier for the inner frame to move in parallel with the surface of the silicon chip (defined as y-axis). Each inner frame is driven by a driver to move in an opposite direction along the y-axis, and also move the proof-mass in the opposite direction along the y-axis. If there is a rotation rate input along the x-axis, it will generate a Coriolis force to make each proof-mass move in the opposite direction of the z-axis. If an acceleration is input along the z-axis, the specific force will move the proof-masses with the same direction. When the proof-masses move or oscillate, the capacitance of the capacitor formed with sensing electrodes will change due to the change of the distance. The moving distance can be obtained by measuring the change of the capacitance. Because the rotation rate outputs an alternating signal, and the acceleration outputs a direct signal, they can be separated with signal processing. The deep vertical etching characteristics of the (110) silicon chip is utilized to make the driving beam in order to control the driving resonance frequency more precisely, and improve the yield rate and the performance of the gyroscope. |