Stacked capacitor with horizontal and vertical fin structures and method for making the same

A method for fabricating a stacked capacitor, comprising:

• providing a substrate having a first interlayer dielectric (ILD) layer thereon and at least one source conductive plate in the first ILD layer;
• depositing a second ILD layer on the first ILD layer;
• forming at least one stacked capacitor area in the second ILD layer;
• forming a film stack comprising alternating first layers and second layers on the second ILD layer and an interior surface of the stacked capacitor area;
• performing a planarization process to planarize the film stack such that a top surface of the second ILD layer is exposed;
• forming a through hole in the film stack, wherein the through hole partially exposes the source conductive plate;
• performing an isotropic etching process to selectively etch the first layers of the film stack via the through hole and the second ILD layer, thereby forming a widened central hole and a fin-shaped structure in the second ILD layer, wherein the fin-shaped structure comprises horizontal fins and vertical fins;
• forming a first conductive layer on the fin-shaped structure;
• forming a capacitor dielectric layer on the first conductive layer;
• and
• forming a second conductive layer on the capacitor dielectric layer.