Method of manufacturing semiconductor pressure sensor

A method of manufacturing a semiconductor pressure sensor on a monocrystal silicon substrate in which the face direction of one face corresponds to the (110) -face, method comprising:

• disposing an etching mask at the one face side of the monocrystal silicon substrate, the etching mask having:
• an opening portion including a first area extending along the <110> crystal axis direction and a second area extending along the <100> crystal axis direction, the first area and the second area crossing each other such that the opening portion has a cross shape, and
• an overlap area including an opening where the first area and the second area of the opening portion overlap, the opening set to be smaller than an area of a diaphragm to be formed in the substrate;
• and
• forming a recess portion on the monocrystal silicon substrate by conducting anisotropic etching from the one face of the monocrystal silicon substrate and also forming a pressure-receiving diaphragm at the bottom surface side of the recess portion in the monocrystal silicon substrate.