METHOD FOR FORMING BIT LINES OF TUNGSTEN

摘要

PURPOSE: A method for forming bit lines of tungsten is provided to reduce a contact resistance and to improve a diffusion barrier characteristic for reducing junction leakage current. CONSTITUTION: A silicon substrate having a dopant area is prepared. An insulation layer having contact holes is formed on the dopant area of the silicon substrate. A titanium layer and a nitride titanium layer are formed on the contact holes. A heat process is performed so that the titanium layer reacts with silicon of the substrate and a titanium silicide of C54 structure is formed. A tungsten plug is formed on the nitride titanium layer within the contact holes.