Abstract: A method is disclosed for fabricating an MDL (Merged DRAM Logic) semiconductor device, in which silicide is formed on a logic region and a memory region selectively for enhancing device reliability. The method includes the steps of (a) providing a substrate having a first region and a second region adjoining the first region, (b) forming a first gate forming material layer in the first region, (c) forming a second gate forming material layer in the first region having the first gate forming material layer formed therein and the second region, (d) selectively patterning the second gate forming material layer to form second gates in the second region and a boundary dummy pattern layer at a boundary area of the first and second regions, and (e) selectively patterning the first gate forming material layer to form first gates in the first region.