Is ArF the final wavelength?

The lithography prognosticator of the early 1980's declared the end of optics for sub-0.5mum imaging. However, significant improvements in optics, photoresist and mask technology continued through the mercury lamp lines (436, 405 & 365nm) and into laser bands of 248nm and to 193nm. As each wavelength matured, innovative optical solutions and further improvements in photoresist technology have demonstrated that extending imaging resolution is possible thus further reducing k(1). Several authors have recently discussed manufacturing imaging solutions for sub-0.3k(1) and the integration challenges. Our industry will continue to focus on the most cost effective solution. What continues to motivate lithographers to discover new and innovative lithography solutions? Recent publications have demonstrated sub 0.30 k(1) imaging. The answer is cost. The development of new tooling, masks and even photoresist platforms impacts cost. The switch from KrF to ArF imaging materials has a significant impact on process integration. The requirements stated in the ITRS roadmap for current and future technology nodes are very aggressive. Therefore, it is likely that high NA in combination with enhancement techniques will continue further for aggressive imaging solutions.