Fabrication of metal suspending nanostructures by nanoimprint lithography (NIL) and isotropic reactive ion etching (RIE)

  • GuoYong XieEmail author
  • Jin Zhang
  • YongYi Zhang
  • YingYing Zhang
  • Tao Zhu
  • ZhongFan LiuEmail author


We report herein a rational approach for fabricating metal suspending nanostructures by nanoimprint lithography (NIL) and isotropic reactive ion etching (RIE). The approach comprises three principal steps: (1) mold fabrication, (2) structure replication by NIL, and (3) suspending nanostructures creation by isotropic RIE. Using this approach, suspending nanostructures with Au, Au/Ti or Ti/Au bilayers, and Au/Ti/Au sandwiched structures are demonstrated. For Au nanostructures, straight suspending nanostructures can be obtained when the thickness of Au film is up to 50 nm for nano-bridge and 90 nm for nano-finger patterns. When the thickness of Au is below 50 nm for nano-bridge and 90 nm for nano-finger, the Au suspending nanostructures bend upward as a result of the mismatch of thermal expansion between the thin Au films and Si substrate. This leads to residual stresses in the thin Au films. For Au/Ti or Ti/Au bilayers nanostructures, the cantilevers bend toward Au film, since Au has a larger thermal expansion coefficient than that of Ti. While in the case of sandwich structures, straight suspending nanostructures are obtained, this may be due to the balance of residual stress between the thin films.


suspending nanostructure fabrication nanoimprint lithography (NIL) isotropic reactive ion etching (RIE) 


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© Science in China Press and Springer-Verlag GmbH 2009

Authors and Affiliations

  1. 1.Center for Nanoscale Science and Technology (CNST), College of Chemistry and Molecular EngineeringPeking UniversityBeijingChina
  2. 2.Nanotechnology Industrialization Base of ChinaTianjinChina

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