title: Subsurface characterization of carbon nanotubes in polymer composites via quantitative electric force microscopy.
abstract: Subsurface characterization of carbon nanotubes (CNTs) dispersed in free-standing polymer composite films was achieved via quantitative electric force microscopy (EFM). The effects of relative humidity, EFM probe geometry, tip-sample distance and bias voltage on the EFM contrast were studied. Non-parabolic voltage dependence of the EFM signal of subsurface CNTs in polymer composites was observed and a new mechanism was proposed taking consideration of capacitive coupling as well as coulombic coupling. We anticipate that this quantitative EFM technique will be a useful tool for non-destructive subsurface characterization of high dielectric constant nanostructures in low dielectric constant matrices.
authors.affiliation: Materials and Construction Research Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA. minhua.zhao@nist.gov
authors.forename: Minhua
authors.initials: M
authors.lastname: Zhao
authors.forename: Xiaohong
authors.initials: X
authors.lastname: Gu
authors.forename: Sharon E
authors.initials: SE
authors.lastname: Lowther
authors.forename: Cheol
authors.initials: C
authors.lastname: Park
authors.forename: Y C
authors.initials: YC
authors.lastname: Jean
authors.forename: Tinh
authors.initials: T
authors.lastname: Nguyen