Neutron Depth Profiling by Large Angle Coincidence Spectroscopy

1994 ◽  
Vol 354 ◽  
Author(s):  
J. Vacík ◽  
J. Cervenä ◽  
V. Hnatowicz ◽  
V. Havränek ◽  
D. Fink
Keyword(s):  
Analytical Method ◽  
Large Angle ◽  
Depth Profiling ◽  
Depth Resolution ◽  
Solid Material ◽  
Detection Sensitivity ◽  
Neutron Depth Profiling ◽  
Depth Profiles ◽  
Low Concentrations ◽  
Coincidence Spectroscopy

AbstractExtremely low concentrations of several technologically important elements (mainly lithium and boron) have been studied by a modified neutron depth profiling technique. Large angle coincidence spectroscopy using neutrons to probe solids with a thickness not exceeding several micrometers has proved to be a powerful analytical method with an excelent detection sensitivity. Depth profiles in the ppb atomic range are accessible for any solid material. A depth resolution of about 20 nanometers can be achieved.

Depth Profiling Investigation of Seawater Using Combined Multi-Optical Spectrometry

2020 ◽  
Vol 74 (5) ◽  
pp. 563-570 ◽  
Author(s):  
Wangquan Ye ◽  
Jinjia Guo ◽  
Nan Li ◽  
Fujun Qi ◽  
Kai Cheng ◽  
...  
Keyword(s):  
Deep Sea ◽  
Depth Profiling ◽  
Deep Ocean ◽  
Euphotic Zone ◽  
Depth Resolution ◽  
Remotely Operated Vehicle ◽  
Sea Trial ◽  
Depth Profiles ◽  
Diving Depth ◽  
Optical Spectrometry

Depth profiling investigation plays an important role in studying the dynamic processes of the ocean. In this paper, a newly developed hyphenated underwater system based on multi-optical spectrometry is introduced and used to measure seawater spectra at different depths with the aid of a remotely operated vehicle (ROV). The hyphenated system consists of two independent compact deep-sea spectral instruments, a deep ocean compact autonomous Raman spectrometer and a compact underwater laser-induced breakdown spectroscopy system for sea applications (LIBSea). The former was used to take both Raman scattering and fluorescence of seawater, and the LIBS signal could be recorded with the LIBSea. The first sea trial of the developed system was taken place in the Bismarck Sea, Papua New Guinea, in June 2015. Over 4000 multi-optical spectra had been captured up to the diving depth about 1800 m at maximum. The depth profiles of some ocean parameters were extracted from the captured joint Raman–fluorescence and LIBS spectra with a depth resolution of 1 m. The concentrations of [Formula: see text] and the water temperatures were measured using Raman spectra. The fluorescence intensities from both colored dissolved organic matter (CDOM) and chlorophyll were found to be varied in the euphotic zone. With LIBS spectra, the depth profiles of metallic elements were also obtained. The normalized intensity of atomic line Ca(I) extracted from LIBS spectra raised around the depth of 1600 m, similar to the depth profile of CDOM. This phenomenon might be caused by the nonbuoyant hydrothermal plumes. It is worth mentioning that this is the first time Raman and LIBS spectroscopy have been applied simultaneously to the deep-sea in situ investigations.

High Resolution Auger Depth Profiles Using a Dual Ion Gun System

1985 ◽  
Vol 54 ◽  
Author(s):  
S. Ingrey ◽  
J.P.D. Cook
Keyword(s):  
Electron Beam ◽  
Depth Profiling ◽  
Depth Resolution ◽  
Grazing Incidence ◽  
Low Energy ◽  
Multilayer Structures ◽  
Dramatic Decrease ◽  
Depth Profiles ◽  
Order Of Magnitude ◽  
Magnitude Improvement

A dual ion gun system has been proposed (D.E. Sykes et al, Appl. Surf. Sci. 5(1980)103) to reduce texturing and improve depth resolution during Auger sputter depth profiling. We have evaluated this ion gun configuration by profiling a variety of multilayer structures. With careful alignment of the guns, we have obtained a dramatic decrease in ion-induced texturing often seen when a single ion gun is used. This effect was particularly pronounced for polycrystalline Al films on Si where an order of magnitude improvement in depth resolution was achieved. Further refinements of the technique include the use of low energy (IkeV) grazing incidence xenon ions and a small electron beam probe area. Depth profiles obtained from Ni/Cr, W/Si, and GaAs/GaAlAs multilayer structures will also be discussed.

Absolute Calibration of Sims Depth Profiles of a-SiNx:H/a-Si:H and a-SiOx:H/a-Si:H Multilayers

1995 ◽  
Vol 382 ◽  
Author(s):  
Jianwei Li ◽  
Jan M. Chabala ◽  
Riccardo Levi-Setti
Keyword(s):  
Cross Sections ◽  
Secondary Ion Mass Spectrometry ◽  
High Spatial Resolution ◽  
Depth Profiling ◽  
Depth Resolution ◽  
Absolute Calibration ◽  
Ion Microprobe ◽  
Depth Profiles ◽  
Atomic Mixing ◽  
Secondary Ion

ABSTRACTWe calibrated secondary ion mass spectrometry (SIMS) depth profiles of a-SiNx:H/a-Si:H and a-SiOx:H/a-Si:H multilayer samples by comparing them to high-spatial-resolution SIMS maps of cross sections through the layers. Both profiles and images were acquired with a focused scanning 45 keV Ga+ ion microprobe. During depth profiling an area gating technique was used to improve depth resolution. At the beginning of the profile the resolution was 8 nm. By cutting the multilayer films at a small angle through the layers, we obtained SIMS images of cross sections through thesemultilayer samples. The resolution along the expanded direction is about 10 nm. By comparing the depth profiles and the cross section images, we determined the ionbeam-induced atomic mixing in the samples, as a function of depth and the sputtering yield for each layer.

Neutron depth profiling by large angle coincidence spectrometry

1993 ◽  
Vol 73 (4) ◽  
pp. 523-530 ◽  
Author(s):  
V. Havránek ◽  
V. Hnatowicz ◽  
J. Kvítek ◽  
J. Vacík ◽  
J. Hoffmann ◽  
...  
Keyword(s):  
Large Angle ◽  
Depth Profiling ◽  
Neutron Depth Profiling

Applications of SIMS to electronic materials and devices

1992 ◽  
Vol 50 (2) ◽  
pp. 1682-1683
Author(s):  
S.F. Corcoran
Keyword(s):  
Depth Distribution ◽  
Secondary Ion Mass Spectrometry ◽  
Semiconductor Device ◽  
Electronic Materials ◽  
Profile Analysis ◽  
Semiconductor Industry ◽  
Small Diameter ◽  
Depth Resolution ◽  
Detection Sensitivity

Over the past decade secondary ion mass spectrometry (SIMS) has played an increasingly important role in the characterization of electronic materials and devices. The ability of SIMS to provide part per million detection sensitivity for most elements while maintaining excellent depth resolution has made this technique indispensable in the semiconductor industry. Today SIMS is used extensively in the characterization of dopant profiles, thin film analysis, and trace analysis in bulk materials. The SIMS technique also lends itself to 2-D and 3-D imaging via either the use of stigmatic ion optics or small diameter primary beams.By far the most common application of SIMS is the determination of the depth distribution of dopants (B, As, P) intentionally introduced into semiconductor materials via ion implantation or epitaxial growth. Such measurements are critical since the dopant concentration and depth distribution can seriously affect the performance of a semiconductor device. In a typical depth profile analysis, keV ion sputtering is used to remove successive layers the sample.

Atomic force microscopy (AFM) of the topography of silicon surfaces exposed to ion beams

1992 ◽  
Vol 50 (2) ◽  
pp. 1132-1133
Author(s):  
Mark Denker ◽  
Jennifer Wall ◽  
Mark Ray ◽  
Richard Linton
Keyword(s):  
Secondary Ion Mass Spectrometry ◽  
Incidence Angle ◽  
Ion Beam ◽  
Depth Profiling ◽  
Depth Resolution ◽  
Ion Beams ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Trace Impurities ◽  
Energy Dose

Reactive ion beams such as O2+ and Cs+ are used in Secondary Ion Mass Spectrometry (SIMS) to analyze solids for trace impurities. Primary beam properties such as energy, dose, and incidence angle can be systematically varied to optimize depth resolution versus sensitivity tradeoffs for a given SIMS depth profiling application. However, it is generally observed that the sputtering process causes surface roughening, typically represented by nanometer-sized features such as cones, pits, pyramids, and ripples. A roughened surface will degrade the depth resolution of the SIMS data. The purpose of this study is to examine the relationship of the roughness of the surface to the primary ion beam energy, dose, and incidence angle. AFM offers the ability to quantitatively probe this surface roughness. For the initial investigations, the sample chosen was <100> silicon, and the ion beam was O2+.Work to date by other researchers typically employed Scanning Tunneling Microscopy (STM) to probe the surface topography.

Investigation of Ge, As, and Au Diffusion in Non-Alloyed Epitaxial Au-Ge Ohmic Contacts to n-GaAs Using Secondary Ion Mass Spectroscopy Backside Sputter Depth-Profiling

1991 ◽  
Vol 240 ◽  
Author(s):  
H. S. LEE ◽  
R. T. Lareau ◽  
S. N. Schauer ◽  
R. P. Moerkirk ◽  
K. A. Jones ◽  
...  
Keyword(s):  
Ohmic Contacts ◽  
Ion Beam ◽  
Depth Profiling ◽  
Depth Resolution ◽  
High Concentration ◽  
Ohmic Behavior ◽  
Preferential Sputtering ◽  
Specific Contact ◽  
Secondary Ion ◽  
Diffusion Profiles

ABSTRACTA SIMS backside sputter depth-profile technique using marker layers is employed to characterize the diffusion profiles of the Ge, As, and Au in the Au-Ge contacts after annealing at 320 C for various times. This technique overcomes difficulties such as ion beam mixing and preferential sputtering and results in high depth resolution measurements since diffusion profiles are measured from low to high concentration. Localized reactions in the form of islands were observed across the surface of the contact after annealing and were composed of Au, Ge, and As, as determined by SIMS imaging and Auger depth profiling. Backside SIMS profiles indicate both Ge and Au diffusion into the GaAs substrate in the isalnd regions. Ohmic behavior was obtained after a 3 hour anneal with a the lowest average specific contact resistivity found to be ∼ 7 × 100−6 Ω- cm2.

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