title: Molecular depth profiling by wedged crater beveling.
abstract: Time-of-flight secondary ion mass spectrometry and atomic force microscopy are employed to characterize a wedge-shaped crater eroded by a 40-keV C(60)(+) cluster ion beam on an organic film of Irganox 1010 doped with Irganox 3114 delta layers. From an examination of the resulting surface, the information about depth resolution, topography, and erosion rate can be obtained as a function of crater depth for every depth in a single experiment. It is shown that when measurements are performed at liquid nitrogen temperature, a constant erosion rate and reduced bombardment induced surface roughness is observed. At room temperature, however, the erosion rate drops by ∼(1)/(3) during the removal of the 400 nm Irganox film and the roughness gradually increased to from 1 nm to ∼4 nm. From SIMS lateral images of the beveled crater and AFM topography results, depth resolution was further improved by employing glancing angles of incidence and lower primary ion beam energy. Sub-10 nm depth resolution was observed under the optimized conditions on a routine basis. In general, we show that the wedge-crater beveling is an important tool for elucidating the factors that are important for molecular depth profiling experiments.
authors: Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
authors: Dan
authors: D
authors: Mao
authors: Caiyan
authors: C
authors: Lu
authors: Nicholas
authors: N
authors: Winograd
authors: Andreas
authors: A
authors: Wucher
mesh_terms: D002084:Butylated Hydroxytoluene / Q000031:analogs & derivatives / Q000737:chemistry; D007477:Ions / Q000737:chemistry; D018625:Microscopy, Atomic Force / Q000379:methods*; D057054:Molecular Imaging / Q000295:instrumentation / Q000379:methods*; D012825:Silicon / Q000737:chemistry; D018629:Spectrometry, Mass, Secondary Ion / Q000379:methods*; D013696:Temperature
chemical_list: D007477:Ions; C547465:Irganox 3114; D002084:Butylated Hydroxytoluene; C045762:Irganox 1010; D012825:Silicon