Plasma Triggered Grain Coalescence for Self-Assembly of 3D Nanostructures

Chunhui Dai, Daeha Joung, Jeong Hyun Cho

Research output: Contribution to journalArticlepeer-review

11 Scopus citations


Grain coalescence has been applied in many areas of nanofabrication technology, includingmodification of thinfilm properties, nanowelding, and self-assembly of nanostructures. However, very few systematic studies of selfassembly using the grain coalescence, especially for threedimensional (3D) nanostructures, exist at present. Here, we investigate the mechanism of plasma triggered grain coalescence to achieve the precise control of nanoscale phase and morphology of the grain coalescence induced by exothermic energy. Exothermic energy is generated through etching a silicon substrate via application of plasma. By tuning the plasma power and the flow rates of reactive gases, different etching rates and profiles can be achieved, resulting in various morphologies of grain coalescence. Balancing the isotropic/anisotropic substrate etching profile and the etching rate makes it possible to simultaneously release 2D nanostructures from the substrate and induce enough surface tension force, generated by grain coalescence, to form 3D nanostructures. Diverse morphologies of 3D nanostructures have been obtained by the grain coalescence, and a strategy to achieve self-assembly, resulting in desired 3D nanostructures, has been proposed and demonstrated.

Original languageUndefined/Unknown
Article number27
JournalNano-Micro Letters
Issue number3
StatePublished - Jul 1 2017

Bibliographical note

Funding Information:
Acknowledgements This material is based upon work supported by an NSF CAREER Award (CMMI-1454293) and a Grant-In-Aid (GIA) program/a start-up fund at the University of Minnesota, Twin Cities. Parts of this work were carried out in the Characterization Facility, University of Minnesota, a member of the NSF-funded Materials Research Facilities Network ( via the MRSEC program. A portion of this work was also carried out in the Minnesota Nano Center which receives partial support from the NSF through the NNCI program. C. D. acknowledges support from the 3M Science and Technology Fellowship.

Publisher Copyright:
© The Author(s) 2017.


  • 3D nanostructures
  • Etching profile
  • Grain coalescence
  • Self-assembly

How much support was provided by MRSEC?

  • Shared

Cite this