Three dimension atom probe analysis of semiconductor materials requires the ability to bring high electric field at the specimen apex to remove atoms. It is shown that, if voltage pulses are used to evaporate doped silicon, the resistivity of the material has to be lower than about 10(2) Omega cm. To overcome this problem, voltage pulses have been replaced by femtosecond laser pulses. The laser pulses give rise to field evaporation by two processes. Both thermal and optical field evaporation have been observed. Thermal evaporation takes place at high laser intensities and with short wavelengths while the evaporation is assisted by the rectification of the optical field for lower intensities and in the infrared domain. Using the optical field evaporation, reproducible and good analyses in term of spatial and mass resolutions could be conducted.
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http://dx.doi.org/10.1016/j.ultramic.2007.02.027 | DOI Listing |
Nanomaterials (Basel)
January 2025
Department of Physics, The University of Western Australia, Perth, WA 6009, Australia.
The capture of magnetic nanoparticles (MNPs) is essential in the separation and detection of MNPs for applications such as magnetic biosensing. The sensitivity of magnetic biosensors inherently depends upon the distribution of captured MNPs within the sensing area. We previously demonstrated that the distribution of MNPs captured from evaporating droplets by ferromagnetic antidot nanostructures can be controlled via an external magnetic field.
View Article and Find Full Text PDFACS Earth Space Chem
January 2025
Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
Naturally occurring bedded salt deposits are considered robust for the permanent disposal of heat-generating nuclear waste due to their unique physical and geological properties. The Brine Availability Test in Salt (BATS) is a US-DOE Office of Nuclear Energy funded project that uses heated borehole experiments underground (∼655 meters depth) at the Waste Isolation Pilot Plant (WIPP) in the bedded salt deposits of the Salado Formation to investigate the capacity for safe disposal of high-level, heat generating nuclear waste in salt. Uncertainties associated with brine mobility near heat-generating waste motivates the need to characterize the processes and sources of brine in salt deposits.
View Article and Find Full Text PDFUltramicroscopy
January 2025
Christian Doppler Laboratory for Sustainable Hard Coatings at the Department of Materials Science, Montanuniversität Leoben, Franz-Josef-Straße 18, 8700 Leoben, Austria.
The impact of the laser wavelength on accuracy in elemental composition analysis in atom probe tomography (APT) was investigated. Three different commercial atom probe systems - LEAP 3000X HR, LEAP 5000 XR, and LEAP 6000 XR - were systematically compared for a TiN model coating studying the effect of shorter laser wavelengths, especially in the deep ultraviolet (DUV) range, on the evaporation behavior. The findings demonstrate that the use of shorter wavelengths enhances the accuracy in elemental composition, while maintaining similar electric field strengths.
View Article and Find Full Text PDFNanoscale
January 2025
College of Materials Science and Engineering, Hubei Provincial Engineering Research Center of Industrial Fiber Preparation and Application, Wuhan Textile University, Wuhan 430200, Hubei, China.
In recent years, solar-driven photothermal water evaporation technology for seawater desalination and wastewater treatment has developed rapidly, which is of great significance for addressing the issue of freshwater scarcity. However, due to the high costs associated with the manufacturing, maintenance, and operation of such devices, their application remains challenging in remote and resource-scarce regions. Due to its excellent light absorption capability in the near-infrared region, high hydrophilicity, and stable chemical properties, coupled with the low cost of recycling waste carbonized polyphenylene sulfide, this material is an excellent choice as a photothermal material for solar-driven water evaporation devices.
View Article and Find Full Text PDFJ Hazard Mater
January 2025
Department of Mechanical, Robotics and Energy Engineering, Dongguk University, Seoul 04620, Republic of Korea. Electronic address:
This paper introduces a highly absorbent and sensitive cellulose nanofiber (CNF)/gold nanorod (GNR)@Ag surface-enhanced Raman scattering (SERS) sensor, fabricated using the vacuum filtration method. By optimizing the Ag thickness in the GNR@Ag core-shell structures and integrating them with CNFs, optimal SERS hotspots were identified using the Raman probe molecule 4-aminothiophenol (4-ATP). To concentrate pesticides extracted from fruit and vegetable surfaces, we utilized the evaporation enrichment effect using hydrophilic CNF and hole-punched hydrophobic polydimethylsiloxane (PDMS).
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