Semiconductor pressure sensor
AssigneeNippondenso Co., Ltd.
InventorsYukihiko Tanizawa, Hiroshi Okada, Kazuhisa Ikeda, Tsuyoshi Fukada
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Abstract
A semiconductor pressure sensor comprises a silicon substrate having a surface orientation of substantially (110), a diaphragm formed from the substrate, strain gauges disposed on the diaphragm, and a base joined with the substrate. The diaphragm has an octagonal shape whose sides are orthogonal to axis<100>, <110>, and<111>, respectively. This sensor causes substantially no output error and no fluctuation between output characteristics of the strain gauges irrespective of a change in temperature.
Claims16
A semiconductor pressure sensor comprising a silicon substrate having a surface orientation of substantially (110), a diaphragm formed from the substrate, strain gauges disposed on the diaphragm, and a base joined with the substrate, wherein the diaphragm is defined by a concave portion which is anisotropically etched in said substrate, a bottom portion of which having an octagonal shape whose sides are orthogonal to axis<100>,<110>, and<111>, respectively.
A semiconductor pressure sensor comprising a silicon substrate having a surface orientation of substantially (100), a diaphragm formed from the substrate, strain gauges disposed on the diaphragm, and a base joined with the substrate, wherein the diaphragm has an octagonal recessed shape whose sides are orthogonal to axes<100>,<110>, and<111>, respectively, said octagonal recessed shape of the diaphragm including a pair of first sides each having a length of l and a pair of parallel second sides spaced apart from each other by a distance L and extending orthogonally to the first sides, wherein l/L is in a range of 0 to 0.5.
A semiconductor pressure sensor comprising an octagonal diaphragm formed by anisotropically etching a semiconductor substrate whose principal plane has a predetermined off-angle with respect to one of the (110) and (100) planes of the semiconductor substrate, a plurality of strain gauges symmetrically arranged on the diaphragm, and a base joined with the substrate, wherein a center of symmetry of the arrangement of strain gauges is at a same position as a center of the bottom of the diaphragm in a direction orthogonal to the principal plane.
Dependencies are inferred from the claim text.