Patent attributes
The present invention relates to a method of forming contact plugs of a semiconductor device. According to the method, a first insulating layer is formed over a semiconductor substrate in which a cell region and a peri region are defined and a first contact plug is formed in the peri region. The first insulating layer is etched using an etch process, thus forming contact holes through which junctions are exposed in the cell region and the first contact plug is exposed in the peri region. Second contact plugs are formed in the contact holes. The second contact plug formed within the contact hole of the peri region are removed using an etch process. A spacer is formed on sidewalls of the contact holes. Third contact plugs are formed within the contact holes.