Semiconductor storage device and method for manufacturing the semiconductor storage device

A semiconductor storage device comprising:

• an insulating layer;
• a ferroelectric capacitor on the insulating layer, the ferroelectric capacitor including a lower electrode, a ferroelectric film, and an upper electrode made of a conductive material containing a noble metal;
• a conductive layer containing Ti which is formed on the upper electrode;
• an interlayer insulating film formed on the insulating layer, the interlayer insulating film having an opening at a part thereof at which the ferroelectric capacitor is disposed;
• a first metal plug formed in the insulating layer and connected to the lower electrode via the opening of the interlayer insulating film;
• a second metal plug embedded in the insulating layer outside the ferroelectric capacitor when viewed planarly;
• and
• a hydrogen barrier film covering the ferroelectric capacitor and the interlayer insulating film, wherein
• an upper surface of the interlayer insulating film is in a level that is higher than a level of an upper surface of the first metal plug so that a step is provided between the upper surface of the interlayer insulating film and the upper surface of the first metal plug,
• the lower electrode is formed on the upper surface of the interlayer insulating film, the upper surface of the first metal plug and the step,
• the ferroelectric capacitor is formed in an upward tapered shape, and
• a boundary portion between the upper electrode and the conductive layer has a concave shape toward a side of the upper electrode.