Extension Options for 193nm Immersion Lithography

The extension of 193nm immersion lithography (193i) has become a requirement due to the current lack of convergence of economic viability and technological capability for any other lithographic technology, at least through the 22nm node. Double patterning is currently the only direct path to 22nm without any clear showstoppers. This technology is expensive because it includes additional costly processing steps. For 22nm and beyond, technical issues such as the need to reduce line edge roughness (LER) or line width roughness (LWR) may drive innovation in lithography. The evaluation of non-chemically amplified photoresist systems may be used to trade resist sensitivity for improved LER and resolution. This work will describe the trade-offs of the candidate technologies for 22nm and beyond and specifically the efforts of several groups to extend 193nm immersion lithography.