Patent ID: 8890631

Claim:
A method for manufacturing a MEMS oscillator, comprising: providing a substrate; forming an interlayer dielectric layer on the substrate, the interlayer dielectric layer forming an drive plate, an anode plug and a cathode plug therein, the anode plug and the cathode plug extending through the interlayer dielectric layer; etching a part of the interlayer dielectric layer, which is located between the anode plug and the cathode plug and above the drive plate, for forming a groove; filling the groove for forming a first sacrifice layer; forming an oscillating beam on the interlayer dielectric layer and the first sacrifice layer, the oscillating beam traversing the groove, opposite sides of the oscillating beam contacting the anode plug and the cathode plug respectively, another opposite sides of the oscillating beam exposing the interlayer dielectric layer; forming a second sacrifice layer on the oscillating beam, the second sacrifice layer connecting with the first sacrifice layer; forming an isolating layer on the second sacrifice layer; etching the isolating layer for forming through holes, the through holes exposing the second sacrifice layer; removing the first sacrifice layer and the second sacrifice layer through the through holes; and forming a covering layer on the isolating layer for covering the through holes, wherein a bottom of the groove is spaced apart from the drive plate by a part of the interlayer dielectric layer.