Abstract
This presentation addresses the challenges to pattern single-digit nanometer nodes. Next generation lithography such as Extreme UV, Multiple E-Beam Direct Write, may or may not help to meet the challenges. Optical lithography may still be needed for all layers, in combination with NGL for relevant layers, or not at all. The consideration will be based on necessary requirements such as overlay accuracy, resolution, and defects. However, even if all these requirements are met, only a satisfactory cost can dictate the application in high volume manufacturing. Some considerations on costs will also be presented.