Pattern shape engineering

Patterning cost and complexity continues to rise with every node. Although EUV lithography has extended dimensional scaling, its limitations have required the industry to implement multi-EUV and other complex patterning schemes. Single exposure EUV patterning is limited by stochastic defects at sub-36nm pitch. Also, counter-scaling between pitch and tip-to-tip spacing limits how close patterned features can be packed in the non-preferred direction. Multi-EUV patterning schemes significantly increase cost while also introducing Edge Placement Errors (EPE). We discuss here an innovative pattern shaping capability which can elongate pre-defined line/space and hole patterns to address these challenges. We will discuss various process knobs including reactive chemistry and material selectivity which can be tuned to allow precision pattern shaping. We will also show how this capability can be used for sidewall processing for applications such as asymmetric spacer removal. Directional pattern shaping has the potential to be a powerful tool in the patterning engineer’s toolbox to help further extend Moore’s law.