Directed self-assembly of PS-b-PMMA block copolymer using HSQ lines for translational alignment

Dipu Borah, Sozaraj Rasappa, Matthew T. Shaw, Richard G. Hobbs, Nikolay Petkov, Michael Schmidt, Justin D. Holmes, Michael A. Morris

Research output: Contribution to journalJournal articleResearchpeer-review


We report here the graphoepitaxial alignment of a lamellar forming PS-b-PMMA block copolymer (BCP) for directed self-assembly using topographical patterns (simple line structures) of hydrogen silsesquioxane (HSQ). The system demonstrates the importance of the sidewall chemistry on translational alignment of BCP domains. A method was developed where a silicon substrate was precoated with a hydroxyl-terminated random copolymer brush of PS-r-PMMA prior to the HSQ feature formation process. The brush ordains the vertical (to the substrate plane) alignment of the BCP lamellar microdomains. Translational BCP alignment is a result of PMMA selectively wetting the HSQ. The formed BCP pattern was selectively etched to remove the PMMA domain allowing direct imaging and to demonstrate capability in forming an on-chip mask. This journal is © 2013 The Royal Society of Chemistry.
Original languageEnglish
JournalJournal of Materials Chemistry C
Issue number6
Pages (from-to)1192-1196
Publication statusPublished - 2013
Externally publishedYes


  • Alignment
  • Block copolymers
  • Brushes
  • Lamellar structures
  • Self assembly
  • Electron beam lithography


Dive into the research topics of 'Directed self-assembly of PS-b-PMMA block copolymer using HSQ lines for translational alignment'. Together they form a unique fingerprint.

Cite this