Patent ID: 8250918

Claim:
A method of manufacturing a mechanical quantity sensor, comprising: forming a first structure having a fixed portion with an opening, a displaceable portion arranged in the opening and displaceable relative to the fixed portion, and a connection portion connecting the fixed portion and the displaceable portion, by etching a first layer of a semiconductor substrate formed by sequentially stacking the first layer formed of a first semiconductor material, a second layer formed of an insulating material, and a third layer formed of a second semiconductor material; arranging and stacking a first base formed of an insulating material on the first structure by joining the first base to the fixed portion; by etching the third layer, forming a second structure having a weight portion joined to the displaceable portion, a recessed portion arranged on a face of the weight portion on a side opposite to a face joined to the displaceable portion or on a face of an area where the weight portion of the third layer is to be formed on a side opposite to a face joined to the displaceable portion, and a pedestal arranged surrounding the weight portion and joined to the fixed portion; and arranging and stacking a second base on the second structure by anodically bonding the second base to the pedestal while the first driving electrode and the first detection electrode are grounded, the second base formed of an insulating material and having a first driving electrode arranged on a face facing the weight portion, formed of a conductive material, and applying vibration in a stacking direction to the displaceable portion, and a first detection electrode arranged on a face facing the weight portion, formed of a conductive material, and detecting a displacement of the displaceable portion, wherein the recessed portion is arranged in an area corresponding to an area where the first driving electrode and the first detection electrode are not arranged.