Low temperature ion bombardment of initially crystalline, defect-free silicon with 700 eV ion beam energy creates a highly-damaged stressed layer a few nanometers thick on the surface. An apparent steady state in structure is achieved at a fluence of 2 · 10–3 · 10 ions/cm. In this work, the stresses are computed using the interatomic force definition of stress. The stress evolution is studied a...

We present a quartz crystal microbalance-based system for high sensitivity differential sputter yield measurements of different target materials due to ion bombardment. The differential sputter yields can be integrated to find total yields. Possible ion beam conditions include ion energies in the range of 30-350 eV and incidence angles of 0 degrees-70 degrees from normal. A four-grid ion optics...

Diffusion and chemical reactions in multicomponent systems play an important role in numerous technology applications. For example, surface treatment of materials and coatings by particle beam leads to chemical composition and grain structure change. To investigate the thermal-diffusion and chemical processes affecting the evolution of surface structure, the mathematical modeling is efficient a...

Instabilities caused during the erosion of a surface by an ion beam can lead to the formation of self-organized patterns of nanostructures. Understanding the self-organization process requires not only the in-situ characterization of ensemble averaged properties but also probing the dynamics. This can be done with the use of coherent X-rays and analyzing the temporal correlations of the scatter...

Fast atom bombardment tandem mass spectrometry, employing ion-molecule reactions with ethyl vinyl ether in a triple-quadrupole mass spectrometer, is used to differentiate classes of phospholipids. The phospholipids are desorbed and ionized by fast atom bombardment, mass-selected by the first quadrupole, and reacted with ethyl vinyl ether in the second quadrupole; the resulting product ions are ...

A precise control of the dimension of carbon nanotubes (CNTs) in their vertical array could enable many promising applications in various fields. Here, we demonstrate the growth of vertically aligned, single-walled CNTs (VA-SWCNTs) with diameters in the sub-1.5-nm range (0.98 ± 0.24 nm), by engineering a catalyst support layer of alumina via thermal annealing followed by ion beam treatment. We ...

A novel approach to elucidate the ionization mechanism for the [M + H]+ molecular ion of organic molecules is investigated by molecular depth profiling of isotopically enriched thin films. Using a model bi-layer film of phenylalanine (PHE) and PHE-D8, the results show formation of an [M + D]+ molecular ion for the non-enriched PHE molecule attributed to rearrangements of chemical damage due to ...

RATIONALE In order to determine the degree of cross-linking on the surface and its variations in a nanometer-scale depth of organic materials, we developed an approach based on time-of-flight secondary ion mass spectrometry (TOF-SIMS), which provides rich chemical information in the form of fragment ions. TOF-SIMS is extremely surface-sensitive and capable of depth profiling with the use of a s...

A study of void and helium sHed bubble stability in amorphous silicon sa-Sid subjected to heavy-ion bombardment was conducted with molecular dynamics simulations. The effects of incident ion energy, incident ion direction, and He pressure were investigated. He bubbles with pressures equal to or greater than 0.1 kbar were found to be stable during isotropic 2 keV xenon sXed irradiation. Bubbles ...

A broad class of “local response” theories seeks to predict morphology evolution during energetic particle irradiation in terms of average surface height response to individual impacts—an approach that has been generalized by the crater function formalism of Norris et al. [J. Phys.: Condens. Matter 21, 224017 (2009); Nat. Commun. 2, 276 (2011)]. Keeping only the terms in the crater function for...