| 摘要 |
PURPOSE:To improve the sensitivity of a semiconductor diaphragm type sensor by a method wherein a thick fixed portion is formed on the periphery of a semiconductor single crystal as a diaphragm material, a thick rigid body portion is formed in the center, and the thin portion therebetween is used as a strain producing portion. CONSTITUTION:A diaphragm 11 made of a semiconductor single crystal of N type silicon consists of a substrate having, e.g.,{100} plane, where a groove-shaped hollow portion 33 is formed by an anisotropic process using alkali etching except for the peripheral thick portion to be a fixed portion 31 and the central thick portion to be a central rigid body 32. The thin portion constituted thereby is used as a strain producing portion 41, on whose upper surface piezoelectric resistance elements 5 are formed by diffusion of P type impurity. The boundary lines between the fixed portion 31 and the strain producing portion 41, and the rigid body portion 32 and the strain producing portion 41 are made to be straight lines perpendicular to the crystal axes <110> of the semiconductor single crystal respectively. |
