Patent ID: 8643927

Claim:
A MEMS device manufacturing method comprising the steps of: (a) providing an SOI substrate including a support substrate, an intermediate insulation layer formed on the support substrate, and an active layer formed on the intermediate insulation layer; (b) following the step (a) and forming a protrusion formation hole in a movable section formation region of the SOI substrate so as to pierce the support substrate and expose the intermediate insulation layer; (c) following the step (b) and removing the intermediate insulation layer exposed from the protrusion formation hole to expose the active layer from the protrusion formation hole; (d) following the step (c) and oxidizing the active layer exposed from the protrusion formation hole and an inner wall of the protrusion formation hole to forma first oxidation layer on a surface of the active layer and the inner wall of the protrusion formation hole; (e) following the step (d) and embedding a conductive film in the protrusion formation hole; (f) following the step (e) and patterning the active layer of the SOI substrate to form an elastic deformation section of a MEMS sensor, a movable section connected to one end of the elastic deformation section, and an unmovable section connected to the other end of the elastic deformation section; (g) following the step (f), removing the intermediate insulation layer from the movable section formation region forming the movable section and the elastic deformation section formation region forming the elastic deformation section to suspend the movable section using the elastic deformation section, partially exposing the conductive film embedded in the protrusion formation hole to form a protruding section including part of the conductive film, and removing the first oxidation layer in contact with the protruding section to form a gap between the protruding section and the movable section.