| 摘要 |
<p>This invention aims to protect an outer peripheral part of an upper surface of a silicon substrate with a protective film using a back plate. A conductive diaphragm (33) is arranged on an upper side of a silicon substrate (32) including a back chamber (35), and the diaphragm (33) is supported with an anchor (37). An insulating plate portion (39) is fixed to an upper surface of the silicon substrate (32) so as to cover the diaphragm (33) with a gap. A conductive fixed electrode film (40) is arranged on a lower surface of the plate portion (39) to configure a back plate (34). The change in electrostatic capacitance between the fixed electrode film (40) and the diaphragm (33) is outputted to outside from a fixed side electrode pad (45) and a movable side electrode pad (46) as an electric signal. A protective film (53) is arranged in continuation to the plate portion (39) at an outer periphery of the plate portion (39), which protective film (53) covers the outer peripheral part of the upper surface of the silicon substrate (32) and the outer periphery of the protective film (53) coincides with the outer periphery of the upper surface of the silicon substrate (32).</p> |
