Patent ID: 8776602

Claim:
A semiconductor device comprising: a membrane formed with first rectangular openings elongated in a first direction and second rectangular openings elongated in a second direction perpendicular to the first direction, the first and second rectangular openings arranged alternately; a support section for supporting a peripheral edge portion of the membrane; a plurality of piezoresistors formed on the membrane; and a weight section formed on a same side as the support section with respect to the membrane and integrally held on a central portion of the membrane, wherein the support section is in the form of a quadrangular annulus in plan view, whose sectional area taken along a plane parallel to the surface connected to the membrane monotonically increases as the support section separates from the membrane, wherein the weight section is in the form of an isosceles trapezoid in section widening as the weight section separates from the membrane, wherein the support section and the weight section are separated from each other by a groove section, and wherein the groove section is in the form of an isosceles trapezoid narrowing upward as the groove section separates from the membrane, the membrane defining a base line of the groove section.