Capacitance structure for preventing degradation of the insulating film

摘要

On a substrate, there are provided a lower electrode, a capacitance insulating film, a passivation insulating film, and a first partial film of an upper electrode to be filled in a second aperture (capacitance determining aperture) formed in the passivation insulating film. The lower electrode, the capacitance insulating film, and the first partial film constitute a capacitance element. The upper electrode has the first partial film which is in contact with the capacitance insulating film and a second partial film which is not in contact with the capacitance insulating film. Since a second electrode wire consisting of a lower-layer film composed of titanium and an upper-layer film composed of an aluminum alloy film is in contact with the second partial film distinct from the first partial film of the upper electrode, titanium or the like encroaching from the second electrode wire can be prevented from diffusing into the capacitance insulating film.