Abstract: A method for fabricating memory device includes forming a bit line pattern including a first conductive layer and a hard mask stacked over a substrate, forming a sacrificial layer on sidewalls of the bit line pattern, forming a second conductive layer in contact with the sacrificial layer and adjacent to the bit line pattern, recessing the second conductive layer, forming an air gap between the recessed second conductive layer and the first conductive layer by removing the sacrificial layer, and forming an air gap capping layer on sidewalls of the hard mask to cap entrance of the air gap.

Abstract: A semiconductor device including a buried gate and a method for forming the same are disclosed. The semiconductor device includes a buffer layer formed on a surface of a trench in a semiconductor substrate, and a gate electrode configured to partially bury the trench and formed of the same material as in the buffer layer.

Abstract: A semiconductor device and a method for forming the same are disclosed. A method for forming a semiconductor device includes forming a trench by etching a semiconductor substrate, forming a barrier metal layer having a thickness of 100 ? or less over a surface of the trench, forming a nucleation layer over the barrier metal layer, configured to include a ?-tungsten (?-W) structure, and forming a bulk layer over the nucleation layer so as to bury the bottom of the trench. As a result, resistivity can be reduced and a stable-phase barrier metal layer can be obtained. In addition, productivity is improved so that gate resistance is prevented from increasing.

Abstract: A semiconductor device including a buried gate and a method for forming the same are disclosed. The semiconductor device includes a buffer layer formed on a surface of a trench in a semiconductor substrate, and a gate electrode configured to partially bury the trench and formed of the same material as in the buffer layer.