| 摘要 |
PURPOSE: To provide a method for forming a capacitive transducer, having a deformable single crystal diaphragm and the structure. CONSTITUTION: A first well region is formed within a semiconductor substrate 30 in an SOI wafer, having a sacrificed layer 31 and a single-crystal silicon layer 20a. A flexible signal crystal membrane is formed by depositing a silicon epitaxial layer. A flexible diaphragm 20 is formed by etching. The sacrificial layer is sealed by depositing an insulating conformal support layer, the sacrificial layer is removed by inserting an etchant from the access opening of the diaphragm, and a diaphragm cavity is formed. A conductive ion is diffused into the faced part of the diaphragm and a first well of the substrate, and a sensitive capacitor 100 is fixed and a variable electrode is formed. Then, the across opening is sealed by having a plug accumulated. A capacitance between the first well region and the conductive region of the diaphragm is correspondingly changed according to the deflection of the diaphragm, in response to the fluctuation between a surrounding pressure and a diaphragm-sealing pressure. |
