A first electrode layer having protrusions and depressions on its surface are formed on a lower insulating layer on a semiconductor substrate, and a sacrificial layer is formed on the first electrode layer with a material that is reflowable when heated. After reflowing the sacrificial layer by heat treatment, the reflowed sacrificial layer and first electrode layer are etched so that the protrusions of the first electrode layer are curved, and a dielectric layer and a second electrode layer are sequentially formed on the first electrode layer. When manufactured using the above method, a thin film capacitor may have higher capacitance without increasing the area of the electrode.