A simulation study has been performed to look at improving the imaging of a l3Onm poly gate mask design. For this lithography process, we have chosen 6% attenuated PSM applied with scattering-bar optical proximity correction (SB-OPC) using 248nm exposure wavelength. We compared the process window performance of off-axis illuminations (OAT) such as QUASAR and annular to a conventional on-axis illumination. Sampled lens aberrations were introduced to the simulation model to evaluate the impact of illumination settings. Simulations show benefits of combining SB-OPC technology with OAI on the performance of 1 3Onm poly gate line features in the presence of known lens aberrations. For this simulation study, we have used our WaveMasterTM software tool to automate the SOLIDCTM simulation loops that includes multiple pre-selected line features from an actual poly gate mask design, five different lens aberration Zerneke data sets, and three illumination settings.