Optimization of pitch-split double patterning photoresist for applications at the 16nm node

Pitch-split resist materials have been developed for the fabrication of sub-74 nm pitch semiconductor devices. A thermal cure method is used to enable patterning of a second layer of resist over the initially formed layer. Process window, critical dimension uniformity, defectivity and integration with fabricator applications have been explored. A tone inversion process has been developed to enable the application of pitch split to dark field applications in addition to standard bright field applications.