Fundamental studies of molecular depth profiling using organic delta layers as model systems

C. Lu, A. Wucher, N. Winograd

Research output: Contribution to journalArticlepeer-review

4 Scopus citations

Abstract

Alternating Langmuir-Blodgett multilayers of barium arachidate (AA) and barium dimyristoyl phosphatidate (DMPA) were used to elucidate the factors that control depth resolution in molecular depth profiling experiments. More specifically, thin (4.4 nm) layers of DMPA were embedded in relatively thick (∼50 nm) multilayer stacks of AA, resulting in a well-defined delta-layer model system closely resembling a biological membrane. This system was subjected to a three-dimensional imaging depth profile analysis using a focused buckminsterfullerene (C60) cluster ion beam. The depth response function measured in these experiments exhibits similar features as those determined in inorganic depth profiling: namely, an asymmetric shape with quasi-exponential leading and trailing edges and a central Gaussian peak. The magnitude of the corresponding characteristic rise and decay lengths is found to be 5 and 16 nm, respectively, while the total half width of the response function characterizing the apparent depth resolution was about 29 nm. Ion-induced mixing is proposed to be largely responsible for the broadening, rather than topography, as determined by atomic force microscopy.

Original languageEnglish (US)
Pages (from-to)81-83
Number of pages3
JournalSurface and Interface Analysis
Volume43
Issue number1-2
DOIs
StatePublished - Jan 2011

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Materials Chemistry

Fingerprint Dive into the research topics of 'Fundamental studies of molecular depth profiling using organic delta layers as model systems'. Together they form a unique fingerprint.

Cite this