Patent ID: 8674452
Filing Date: 2014-03-18
Classification: H01L

Abstract:
1. A semiconductor device, comprising: a substrate having a first region and a second region; a first gate structure disposed on the first region, wherein the first gate structure comprises a first high-k dielectric layer, a first work function metal layer, and a first metal layer and a third metal layer disposed between the first high-k dielectric layer and the first work function metal layer, wherein the third metal layer is U-shaped; a second gate structure disposed on the second region, wherein the second gate structure comprises a second high-k dielectric layer, a second work function metal layer, and a second metal layer disposed between the second high-k dielectric layer and the second work function metal layer, wherein the first metal layer, the second metal layer, and the third metal layer are made of the same material; a first source/drain disposed in the substrate adjacent to two sides of the first gate structure; and a second source/drain disposed in the substrate adjacent to two sides of the second gate structure.