Patent ID: 6570233
Filing Date: 2003-05-27
Classification: H01L

Abstract:
A semiconductor integrated circuit device comprising:a substrate; a transistor formed on said substrate, said transistor comprising a source, a drain and a gate which controls a current flowing from said source to said drain; an insulating layer formed over transistor and having a contact hole therein; and a contract plug, formed in the contact hole, which is electrically connected to one of said source and said drain and made of a conductive material including a dopant; wherein said contact plug is formed of at least a first layer lining the contact hole, and a second layer lining the first layer, said first layer contacting with one of said source and drain and being made of said material including the dopant of a first concentration; said second layer being made of said material including the dopant of a second concentration lower than the first concentration; and wherein one of said source and drain is a region into which ions are injected with a first energy level and with a second energy level which is higher than the first energy level, and the ions injected with said second energy level are injected via said first layer.