Patent ID: 7932117

Claim:
A manufacturing method of a pressure sensor including a plate having a fixed electrode, a diaphragm that has a moving electrode positioned opposite to the fixed electrode and that is subjected to displacement due to pressure variations applied thereto, and a support having at least one cavity for supporting the plate, said manufacturing method comprising: depositing a thin film forming the plate and a thin film forming the diaphragm on a first surface of a substrate; forming a first mask having a first opening on a second surface opposite to the first surface of the substrate; forming a second mask having a second opening on the second surface of the substrate, wherein the second mask covers the first mask so that a prescribed portion of the substrate just above the thin film forming the plate is exposed in the second opening; forming a recess by performing anisotropic etching on the substrate exposed in the second opening by use of the second mask; removing the second mask while allowing the first mask to remain; and performing anisotropic etching using the remaining first mask on the substrate exposed in the first opening such that a bottom of the recess is removed, thus forming a through-hole forming the cavity in the substrate.