Patent ID: 8383483
Filing Date: 2013-02-26
Classification: H01L

Abstract:
1. A method for forming a semiconductor device comprising: providing a semiconductor substrate containing at least first device region and a second device region adjacent to each other; forming a first gate stack located over the first device region, wherein said first gate stack comprises at least, from bottom to top, a first gate dielectric layer and a first silicon-containing gate conductor located on a surface of said first gate dielectric layer; and forming a second gate stack located over the second device region, wherein said second gate stack comprises a second gate dielectric layer comprising a dielectric material having a dielectric constant (k) equal to or greater than that of silicon dioxide on the semiconductor substrate, a metal containing layer present on the second gate dielectric, the metal containing layer selected from the group consisting of a rare earth metal-containing layer, an alkaline earth metal-containing layer an a combination of a rare earth metal-containing layer, a metallic gate conductor present on the metal containing layer, and a second silicon-containing gate conductor present on the metallic gate conductor.