Currently,200 mm wafer foundry companies are beginning to explore production feasibility under ground rules smaller than 0.11μm while maintain the cost advantages of KrF exposure tool systems.The k1 factor under 0.11μm at 248 nm illumination will be below 0.35,which means the process complexity is comparable with 65 nm at 193 nm illumination.In this paper,we present our initial study in the CD process window,mask error factor and CD through pitch performance at the 0.09μm ground rule for three critical layers——gate poly,metal and contact.The wafer data in the process window and optical proximity will be analyzed.Based on the result,it is shown that the KrF tool is fully capable of sub 0.11μm node mass production. Currently, 200 mm wafer foundry companies are beginning to explore production feasibility under ground rules smaller than 0.11 μm while maintaining the cost advantages of KrF exposure tool systems. The k1 factor under 0.11 μm at 248 nm illumination will be below 0.35, which means the process The complexity is comparable with 65 nm at 193 nm illumination. This paper, we present our initial study in the CD process window, mask error factor and CD through pitch performance at the 0.09 μm ground rule for three critical layers - gate poly, metal and contact. The wafer data in the process window and the optical proximity will be analyzed. Based on the result, it is shown that the KrF tool is fully capable of sub 0.11 μm node mass production.