Density driven placement of sub-DSA resolution assistant features (SDRAFs)

Daifeng Guo, Maryann Tung, Ioannis Karageorgos, H. S.Philip Wong, Martin D.F. Wong

Research output: Chapter in Book/Report/Conference proceedingConference contribution


In the pursuit of alternatives to traditional optical lithography, block copolymer directed self-assembly (DSA) has emerged as a low-cost, high-throughput option. However, issues of defectivity have hampered DSA's viability for large-scale patterning. Recent studies have shown copolymer fill level to be a crucial factor in defectivity, as template overfill can result in malformed DSA structures and poor LCDU after etching. For this reason, it is previously demonstrated the use of sub-DSA resolution assist features (SDRAFs) as a method of evening out template density. In this work, we propose an algorithm to place SDRAFs in random logic contact/via layouts. By adopting this SDRAF placement scheme, we can significantly improve the density unevenness and the resources used are also optimized. This is the first work to investigate the placement of SDRAFs in order to mitigate the DSA density variation problem, and it can be adopted for the mass deployment of DSA.

Original languageEnglish (US)
Title of host publicationDesign-Process-Technology Co-optimization for Manufacturability XI
EditorsJason P. Cain, Luigi Capodieci
ISBN (Electronic)9781510607477
StatePublished - 2017
EventDesign-Process-Technology Co-optimization for Manufacturability XI 2017 - San Jose, United States
Duration: Mar 1 2017Mar 2 2017

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


OtherDesign-Process-Technology Co-optimization for Manufacturability XI 2017
Country/TerritoryUnited States
CitySan Jose


  • Density
  • Directed self-assembly
  • Placement
  • Sub-DSA assistant features

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


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