This tutorial encompasses two decades of research it discusses theoretical and practical aspects of commonly used techniques including optical imaging and resolution modified illumination optical proximity correction alternating and attenuating phase shifting masks selecting rets and second generation rets useful for students and practicing lithographers. This tutorial summarizes optical lithography enhancement research and development over the past 20 years discusses theoretical and practical aspects of commonly used techniques including optical imaging and resolution modified illumination optical proximity correction alternating and attenuating phase shifting masks selecting rets and second generation rets. Ever smaller ic devices are pushing the optical lithography envelope increasing the importance of resolution enhancement techniques this tutorial encompasses two decades of research it discusses theoretical and practical aspects of commonly used techniques including optical imaging and resolution modified illumination optical proximity correction alternating and attenuating phase . The acceleration of integrated circuit miniaturization is challenging lithographers to push the limits of optical lithography by ever more precise engineering and innovations as ic device dimensions grow smaller circuits outpace the introduction of shorter exposure wavelengths and higher numerical aperture lenses increasing the importance of resolution enhancement techniques. Get this from a library resolution enhancement techniques in optical lithography alfred kwok kit wong ever smaller ic devices are pushing the optical lithography envelope increasing the importance of resolution enhancement techniques this tutorial encompasses two decades of research it discusses