Abstract: A semiconductor device comprising a semiconductor substrate having a first impurity region and a second impurity region, a first gate pattern formed on the first impurity region, and a second gate pattern formed on the second impurity region is disclosed. The first gate pattern comprises a first gate insulation layer pattern, a metal layer pattern having a first thickness, and a first polysilicon layer pattern. The second gate pattern comprises a second gate insulation layer pattern, a metal silicide layer pattern having a second thickness smaller than the first thickness, and a second polysilicon layer pattern. The metal silicide layer pattern is formed from a material substantially the same as the material from which the metal layer pattern is formed. A method for manufacturing the semiconductor device is also disclosed.

Abstract: A method of forming transistor gate structures in an integrated circuit device can include forming a high-k gate insulating layer on a substrate including a first region to include PMOS transistors and a second region to include NMOS transistors. A polysilicon gate layer can be formed on the high-k gate insulating layer in the first and second regions. A metal silicide gate layer can be formed directly on the high-k gate insulating layer in the first region and avoiding forming the metal-silicide in the second region. Related gate structures are also disclosed.

Abstract: A method of forming an oxide layer on a semiconductor substrate includes thermally oxidizing a surface of the substrate to form an oxide layer on the substrate, and then exposing the oxide layer to an ambient including predominantly oxygen radicals to thereby thicken the oxide layer. Related methods of fabricating a recessed gate transistor are also discussed.

Abstract: A method of forming an oxide layer on a semiconductor substrate includes thermally oxidizing a surface of the substrate to form an oxide layer on the substrate, and then exposing the oxide layer to an ambient including predominantly oxygen radicals to thereby thicken the oxide layer. Related methods of fabricating a recessed gate transistor are also discussed.