Oct. 19, 2006 — IMEC, the Leuven, Belgium, independent research center for micro and nanotech, showed in collaboration with ASML the potential of double patterning 193nm immersion lithography at 1.2NA for 32nm node Flash and logic.
These organization said in a statement that the results prove that double patterning might be an intermediate solution before extreme ultraviolet (EUV) lithography and very high NA (beyond water) 193nm immersion lithography will be ready for production.
The results were obtained by splitting gate levels of 32nm half pitch Flash cells as well as logic cells in two complementary designs. The splitting was done automatically using software from EDA partners in IMEC’s lithography program. After splitting, both designs received optical proximity corrections (OPC) and a classical lithography approach “litho-etch-litho-etch” was performed. Exposures of both lithography steps have been carried out on an XT:1700i at ASML.
These results show that the XT:1700i 193nm immersion tool, which has a maximum NA of 1.2, could be extended beyond the 45nm node. Since both hyper NA 193nm immersion lithography using high-index liquids and EUV still require a lot of research, IC manufacturers welcome double patterning as a solution to continue their research on material integration for the 32nm node.