A method to reduce the inverse-narrow-line-effect is described in which an active region and an isolation region are defined on a substrate. A doped region is formed adjacent to the substrate surface, wherein the area of the doped region includes the isolation region and the edge of the active region. The depth of the doped region is shallower than that of the source/drain region formed subsequently. A shallow trench is formed thereafter in the isolation region adjacent to the active region, such that the doped region located in the substrate at the edge of the active region is retained. A liner oxide layer is further formed on the inner wall of the shallow trench. An oxide layer, which is as high as the surface of the cap layer, is formed to fill the trench. After the removal of the pad oxide layer and the cap layer, a gate oxide layer and a gate are formed on the substrate.