Capacitance type sensor and method of manufacturing the same

摘要

A capacitance type sensor has a semiconductor substrate having a vertically opened penetration hole, a movable electrode film arranged above the penetration hole such that a periphery portion opposes to a top surface of the semiconductor substrate with a gap provided, and a fixed electrode film arranged above the movable electrode film with a gap with respect to the movable electrode film. A concave portion having at least a part thereof formed by an inclined surface is provided in the top surface of the semiconductor substrate in a region of the top surface of the semiconductor substrate which overlaps the periphery portion of the movable electrode film.

主权项

1. A capacitance type sensor comprising:
a semiconductor substrate comprising a vertically opened penetration hole; a movable electrode film arranged above the penetration hole such that a periphery portion is opposite to a top surface of the semiconductor substrate with a gap provided therebetween; and a fixed electrode film arranged above the movable electrode film with a gap between the fixed electrode film and the movable electrode film, wherein a concave portion having at least a part thereof formed by an inclined surface is provided in the top surface of the semiconductor substrate in a region of the top surface of the semiconductor substrate which overlaps the periphery portion of the movable electrode film, wherein the concave portion is formed such that, in at least part of an opening of a top surface of the concave portion to a bottom surface side of the opening in the semiconductor substrate, a cross-sectional area of the concave portion parallel to the top surface of the semiconductor substrate becomes smaller from the opening of the top surface of the concave portion to the bottom surface side of the opening in the semiconductor substrate, and wherein the inclined surface of the concave portion is formed by a densest crystal plane of a material of the semiconductor substrate.