Hotspot management and its applications in ultralow <inline-formula><math display="inline" overflow="scroll"><msub><mi mathvariant="normal">k</mi><mn>1</mn></msub></math></inline-formula> lithography

Abstract

We have constructed a hotspot management flow and applied the flow to large-scale integration (LSI) manufacturing in the ultralow k1 lithography era. This flow involves three main management steps: hotspot reduction, hotspot extraction, and hotspot monitoring. Hotspot reduction works with lithography-friendly restricted design rule (RDR) and manufacturability check (MC). Hotspot extraction is carried out with a view to realizing short operation time and accurate extraction. Hotspot monitoring is achieved with tolerance-based verification in the mask fabrication process and wafer process (lithography and etching). These technology elements could be integrated into the LSI fabrication flow for reduction of total cost, quick turnaround time (TAT), and ramp-up to volume production. In addition to discussion of the technology elements in hotspot management, we also provide typical applications for important decisions in LSI fabrication: photomask availability for any exposure tools ("exposure tool yokoten") and process condition updates in LSI fabrication.