Application of super-diffraction-lithography (SDL) for advanced logic

~30nm width isolated line is formed with over 300nm DOF by Single Exposure process of ArF immersion lithography. Super-Diffraction-Lithography ("SDL") technique, which utilizes fine dark line image formed between a pair of bright lines in attenuating non-phase-shifting field and which enables formation of very fine isolated line pattern with single exposure, is applied with ArF immersion lithography. By simulation study, superior performance of "SDL" is exhibited for ArF immersion lithography. From view point of mask fabrication, it is shown that requirement for mask technology is not so severe, such that photo mask for "SDL" in hyper NA ArF immersion era can be fabricated with current mask technology. By experiments with an optimum quadrupole illumination, ~30 nm width isolated line is successfully printed by single exposure process with over 300nm DOF by a mature 6% transmission EA-PSM. Moreover, device like pattern with ~35nm line width is well formed with enough large DOF to industrially fabricate devices. We believe this technique is one of the promising candidates for advanced logic at 32 nm node and beyond.