Physical quantity sensor having multiple through holes

A semiconductor physical quantity sensor comprising:

• a substrate;
• a semiconductor layer supported on the substrate;
• a plurality of trenches disposed in the semiconductor layer;
• and
• a movable portion disposed in the semiconductor layer and separated from the substrate by the trenches, wherein
• the movable portion includes a plurality of through-holes, each of which penetrates the semiconductor layer in a thickness direction,
• the movable portion is capable of displacing on the basis of a physical quantity applied to the movable portion so that the physical quantity is detected by a displacement of the movable portion, and
• one of the through-holes in the movable portion or one of the trenches disposed outer periphery of the movable portion has a width capable of performing a maximum etching rate of the semiconductor layer adjacent to the through-hole or the trench.