Thin-film capacitor

A thin-film capacitor comprising:

• a plurality of electrode layers that are stacked in a stacking direction;
• a plurality of dielectric layers that are stacked between the plurality of electrode layers;
• an opening portion that includes a side surface penetrating at least a part of the plurality of electrode layers and at least a part of the plurality of dielectric layers in the stacking direction from a top side and a bottom surface exposing one electrode layer of the plurality of electrode layers;
• and
• a wiring portion that is disposed in the opening portion to be separated from the side surface of the opening portion and is electrically connected to the electrode layer exposed from the bottom surface of the opening portion,
• wherein the dielectric layer that is stacked immediately on the electrode layer exposed from the bottom surface of the opening portion among the plurality of dielectric layers includes an extension portion extending in the opening portion from the side surface of the opening portion to a wiring portion side,
• the side surface of the opening portion has a continuous plane shape, and the extension portion extends from the side surface, and
• a thickness of the extension portion is smaller than a thickness of the dielectric layer stacked immediately on the electrode layer exposed from the bottom surface of the opening portion.