The air-in via hole is provided with a lifting post which can seal the air-in via hole;
A conductive member contacts the upper electrode on a bottom of the via hole.
A via hole is formed through the interlayer insulating film and reaches a position deeper than an upper surface of the upper electrode.
The control rod is inserted into the containing via hole from top to bottom, and the lower end of the control rod supports against on the fusible body.
