Patent ID: 8482138

Claim:
A three-dimensional semiconductor device, comprising: a first electrode structure disposed on a substrate, the first electrode structure having first electrodes which are stacked on the substrate; and a second electrode structure disposed on the first electrode structure, the second electrode structure having second electrodes which are stacked on the first electrode structure; an interconnection structure having lower plugs and being disposed on the second electrode structure; wherein each of the first and second electrodes has a horizontal portion parallel with the substrate and an extension portion extending from the horizontal portion along a direction penetrating an upper surface of the substrate; the horizontal portions of the first and second electrodes are gradually shortened as a distance between the first and second electrodes and the substrate increases; and the substrate is closer to top surfaces of the extension portions of the first electrodes than to the horizontal portion of at least one of the second electrodes; wherein the lower plugs comprise first plugs connected to the first electrodes and second plugs connected to the second electrodes, the second plugs being shorter than the first plugs.