| 摘要 |
PURPOSE:To mass-produce dynamic-quantity sensors having uniform charac teristics by precisely forming the thickness of a cantilever as a dynamic-quantity responding section and a diaphragm. CONSTITUTION:A groove 8 in depth corresponding to the thickness of a cantilever is formed from the surface of an Si substrate 1, and piezo-resistors 16 for detecting strain are shaped previously on both sides of the groove 8, but the piezo-resistors are formed where shorter than 0.7 times as long as the depth of the groove from the groove. A groove oxide 9, a surface insulating film 11 and a back insulating film 12 are shaped and oxidizing the surface and back of the Si substrate 1, and a packing as a beam structure 10 is buried into the groove 8. One parts of the back insulating film 12 are removed, and a hole 13 for forming a beam and a hole 14 for shaping an air gap are formed, but remaining section in the back insulating film 12 function as masks 15 for etching the back. The Si substrate 1 is etched in an anisotropic manner from the back. Etching progresses in sections to which the groove oxide 9 is not shaped, the air gaps 18 are formed, Si is left obliquely on both side walls of the groove, and the Si sections serve as the piezo-resistor sections 16.
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