What is NanoSIMS? This analytical instrument uses secondary ion mass spectrometry to obtain nanoscale resolution measurements of the sample’s composition. This method can be used to determine the precise location of hydrogen in a sample. It is an extremely sensitive chemical analysis technique. Read on to find out more about this analytical method. We hope you’ll find it useful. Here are some of its most common uses:
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Secondary ion mass spectrometry
The technology used in secondary ion mass spectrometry includes a primary ion gun, a secondary ion extraction lens, and a high vacuum sample chamber. It then uses a secondary ion mass analyser to separate ions by charge and mass ratio. The resulting data provide detailed information about the characteristics of the sample. There are several benefits to this method. Here are a few of them:
SIMS is used to determine the concentrations of impurities and dopants in semiconductors. This process measures the secondary ion count rate of selected elements over a period of time, and depth profiles can be generated. For example, SIMS is used to determine the concentration of phosphorous in silicon, a compound fabricated using ion implantation. To do this, SIMS analysts use Cs+ primary ions. The depth of the crater is determined by multiplying the total sputtering time by the average sputter rate, and then use relative sensitivity factors to convert ion counts into concentrations.
It provides in situ elementary and isotopic information
The in situ analysis of isotopes is a key process in almost all branches of science. Moreover, these isotopes serve as powerful markers in various research studies. For example, isotopes are used in archaeology to date fossilized material. And geochronology and geochemistry use this method to understand the earliest stages of planet formation. As a result, isotope analysis plays a crucial role in these fields.
In-situ analysis of isotopic compositions of geological material can be performed without the use of laboratory procedures. Because natural geological materials are heterogeneous, a wide variety of high resolution micro-analytical techniques are used to obtain in situ isotopic compositions. These include laser ablation ICP-MS, secondary ionization mass spectrometry (SIMS), and multi-collector ICP-MS. The LA-(MC)-ICP-MS technique has gained popularity in the geochemistry field in the last few decades. Unlike conventional methods, it can measure trace elements and isotopic ratios at the sub-grain level.
It is a highly sensitive chemical analysis technique
NanoSIMS is a highly sensitive chemical analysis technique based on a unique design. It uses two primary ion sources: Cs+ and O-. The Cs+ source generates negative secondary ions and is focused to sub-50 nm. The O and O2+ primary ions are generated by a duoplasmatron with a small beam diameter of 150 nm. The nanoscale structure of the primary beams allows them to be simultaneously extracted and imaged.
This highly sensitive analytical technique can detect interface contamination and doping in layered structures. In semiconductors, it can also detect polymer cracks and voids. For optimal sensitivity, the ejected material must have a high proportion of ionised molecules. The likelihood of ejection depends on the chemical environment in which it arose. Reactive ion beams can increase the yield of electronegative species by altering the chemistry of the altered layer.
It is used to determine where in the microstructure hydrogen is located
Hydrogen embrittlement is a serious concern in safety-critical industries such as aerospace, oil/gas, and nuclear. NanoSIMS mapping can help identify localised hydrogen in microstructures. It can also provide deuterium distribution and identify hydrogen-containing regions. NanoSIMS can help identify hydrogen-containing features in materials that are not readily accessible by other methods.
In order to determine where in the microstructure hydrogen is localized, scientists can create a simulated model of a deformed sample with the correct structure. The simulation results show that hydrogen accelerated the deformation process and trapped dislocations in unlikely configurations. Hydrogen-enhanced plasticity mediated processes were also identified. It is important to note that the results are not conclusive.
It uses stable isotope probing
Stable isotope probing is a biological technique that utilizes isotopes to trace the flow of elements in a variety of substances and organisms. This method can also be used to detect biomarkers, such as DNA and RNA, which are the most informative taxonomic markers. Its benefits are wide-ranging, and the technique is being increasingly applied to biotechnology and environmental monitoring.
One of the most important applications of stable isotopes is the study of microbial communities. This technique has been used to determine the rate of substrate assimilation and growth by studying the interactions of microbes with their environment. In the present study, researchers used 13C-labeled substrates and DNA-SIP to study microbial response to these substrates. In the future, this technology may be used to identify specific bacterial lineages responsible for the incorporation of these DOM compounds.
It uses an electron gun for analysis of insulating samples
The SE technique involves using an electron gun to analyze insulating samples. The instrument uses an electron beam that has a diameter of 150 mm to analyze samples. The sensitivity of the SE technique depends on the instrument’s operating parameters, which include the primary beam current and specimen chamber vacuum. The holder for the sample contains a common control metal that suppresses uncertainties created by parameter changes.
The SE energy spectra were measured at two kV primary beam voltages and ten test specimens. The spectral peak heights of Au and Pt indicate material contrast. These spectra were compared against a gold foil control sample. Gold foil served as a control sample to suppress variations due to specimen holder exchange. The background signal at the 0 eV pass energy was removed from each spectra to calculate the spectral energy.