Extension of low k1 lithography processes with KrF for 90nm technology node

We discussed to KrF process extension for 90 nm technology node. The continuous shrinkage of critical dimensions on sub 130 nm devices becomes a key point to improve process margin with pattern resolution problem for lithography. Recently, according to development demand of high density and high integration device, it is tendency that the shrink rate of design rule is gradually accelerated. It is difficult to develop with image contrast problem around k1=0.25 which is a theoretical process limit region. We need to technology development which is available to having resolution for sub 90nm line and space by using KrF lithography not by using ArF lithography. In generally, KrF have not been used in nano-process such as 90nm technology. In this study, however, we can apply the KrF in 90nm technology by means of minimizing the error range in the nano-process, optimizing the process, and extending the process margin. This Application of KrF in 90nm technology results in elimination of additional investment for development of 90nm technology. Finally, we will show which simulation and experimental results such as normalized image log slope, pupil plane, image of focus variation, process window, top view image, photo resist and etch profile, and pitch linearity.