| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor pressure sensor which is low-cost and has high sensitivity. SOLUTION: This sensor is equipped with a semiconductor sensor chip 10 which has four piezoresistances R1, R2, R3, and R4 on the main surface side of a single-crystal silicon (110) substrate 1. The piezoresistances R1 to R4 are connected on a bridge basis. The respective piezoresistances R1 to R4 constitute pressure sensing elements which detect the deformation of a diaphragm part 2. The plane shape of the diaphragm part 2 is made rectangular. Denoting as H2 the length of the side parallel to the <001> direction of the substrate of the single-crystal silicon (110) substrate 1 in the plane shape of the diaphragm part 2 and as H2 the length of the side orthogonal to the <001> direction, the ratio H1/H2 is so set as to obtain desired sensitivity corresponding to the thickness of the diaphragm part 2. Here, nearly maximum sensitivity can be obtained on condition that the diaphragm part 2 is 150μm thick and has the ratio H1/H2 of 1.4 and the area of the main surface of the diaphragm part 2 is constant.
|
