Journal articles: 'Electron-Beam-Induced Annealing'

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Muntifering, Brittany, Rémi Dingreville, Khalid Hattar, and Jianmin Qu. "Electron Beam Effects during In-Situ Annealing of Self-Ion Irradiated Nanocrystalline Nickel." MRS Proceedings 1809 (2015): 13–18. http://dx.doi.org/10.1557/opl.2015.499.

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ABSTRACTTransmission electron microscopy (TEM) is a valuable methodology for investigating radiation-induced microstructural changes and elucidating the underlying mechanisms involved in the aging and degradation of nuclear reactor materials. However, the use of electrons for imaging may result in several inadvertent effects that can potentially change the microstructure and mechanisms active in the material being investigated. In this study, in situ TEM characterization is performed on nanocrystalline nickel samples under self-ion irradiation and post irradiation annealing. During annealing, voids are formed around 200 °C only in the area illuminated by the electron beam. Based on diffraction patterns analyses, it is hypothesized that the electron beam enhanced the growth of a NiO layer resulting in a decrease of vacancy mobility during annealing. The electron beam used to investigate self-ion irradiation ultimately significantly affected the type of defects formed and the final defect microstructure.

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Tripathi, S., R. Brajpuriya, A. Sharma, T. Shripathi, and S. M. Chaudhari. "Annealing induced structural changes in electron beam evaporated Si/Ge multilayers." European Physical Journal Applied Physics 34, no. 1 (March 23, 2006): 13–19. http://dx.doi.org/10.1051/epjap:2006028.

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Váczi, Tamás, and Lutz Nasdala. "Electron-beam-induced annealing of natural zircon: a Raman spectroscopic study." Physics and Chemistry of Minerals 44, no. 6 (December 2, 2016): 389–401. http://dx.doi.org/10.1007/s00269-016-0866-x.

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Mizuno, Naomi, Fernando Camino, and Xu Du. "In Situ Study of the Impact of Aberration-Corrected Electron-Beam Lithography on the Electronic Transport of Suspended Graphene Devices." Nanomaterials 10, no. 4 (April 2, 2020): 666. http://dx.doi.org/10.3390/nano10040666.

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The implementation of aberration-corrected electron beam lithography (AC-EBL) in a 200 keV scanning transmission electron microscope (STEM) is a novel technique that could be used for the fabrication of quantum devices based on 2D atomic crystals with single nanometer critical dimensions, allowing to observe more robust quantum effects. In this work we study electron beam sculpturing of nanostructures on suspended graphene field effect transistors using AC-EBL, focusing on the in situ characterization of the impact of electron beam exposure on device electronic transport quality. When AC-EBL is performed on a graphene channel (local exposure) or on the outside vicinity of a graphene channel (non-local exposure), the charge transport characteristics of graphene can be significantly affected due to charge doping and scattering. While the detrimental effect of non-local exposure can be largely removed by vigorous annealing, local-exposure induced damage is irreversible and cannot be fixed by annealing. We discuss the possible causes of the observed exposure effects. Our results provide guidance to the future development of high-energy electron beam lithography for nanomaterial device fabrication.

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HEILMANN, A., A. D. MÜLLER, and J. WERNER. "SIZE AND SHAPE MANIPULATION OF SILVER AND INDIUM SMALL PARTICLES BY ELECTRON-BEAM IRRADIATION." Surface Review and Letters 03, no. 01 (February 1996): 1113–19. http://dx.doi.org/10.1142/s0218625x96001996.

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Small particles of indium or silver were encapsulated in a thin polymer film matrix by simultaneous plasma polymerization and metal evaporation. Electron-beam irradiation inside transmission electron microscopes and with a microfocus electron source was used to induce changes of the encapsulated particle size and shape. At encapsulated indium particles, substantial microstructural changes were observed during the electron-beam irradiation in the electron microscope. Selected area diffraction demonstrates that indium oxide was formed during the electron irradiation. Additional in situ annealing demonstrates that the indium melting point was not reached during electron-beam-induced local heating of the indium particles. At electron-beam irradiation of plasma polymer films with encapsulated silver particles by using a microfocus electron source, the coalescence of the silver particles can be limited to the irradiated areas of the films.

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Kato, Tetsuji, Yoshiaki Nakamura, P. P. T. Son, Jun Kikkawa, and Akira Sakai. "Electron-Beam-Induced Current Study of Electronic Property Change at SrTiO₃ Bicrystal Interface Induced by Forming Process." Materials Science Forum 725 (July 2012): 261–64. http://dx.doi.org/10.4028/www.scientific.net/msf.725.261.

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We investigated the spatial variation of energy band structure in a SrTiO3 (001) bicrystal with the (100) 10° tilt boundary before and after the annealing process at 973 K under a vacuum of ~10-7 Torr and after the subsequent forming process with electrical dielectric breakdown, using electron beam induced current (EBIC) method in the temperature range between 200 and 300K. Although the EBIC contrast at the tilt boundary was weak before and after the annealing, it became visible after the forming process and stronger as the observation temperature decreased to less than 260 K. It was found that the EBIC direction at the tilt boundary is opposite to that in the matrix, i.e. the single crystalline regions of both sides of the tilt boundary. In the matrix, the EBIC increased after the annealing and decreased again after the forming process. We propose energy band structures of the bicrystalline SrTiO3 after the annealing and after the forming process.

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Соковнин, С. Ю., В. Г. Ильвес, М. Г. Зуев, and М. А. Уймин. "Магнитные и люминесцентные свойства нанопорошка фторида бария, полученного методом испарения импульсным электронным пучком в газе низкого давления." Письма в журнал технической физики 44, no. 17 (2018): 19. http://dx.doi.org/10.21883/pjtf.2018.17.46566.17270.

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AbstractMesoporous amorphous-crystalline nanopowders of BaF_2 with the specific surface area up to 34.8 m^2/g were obtained using evaporation by a pulsed electron beam in vacuum. Influence of the thermal annealing of the BaF_2 nanoparticles in air at the temperatures from 200 to 900°C on the size and morphology of the particles and changes in their magnetic and luminescent properties was studied. The paramagnetic response of the BaF_2 nanopowder was found to transform to the ferromagnetic response after annealing at 900°C. The appearance and transformation of the magnetic response in nanopowders made of BaF_2, which is diamagnetic as the bulk material, are ascribed to the appearance of radiation-induced and structural defects during the synthesis process by pulsed electron-beam evaporation.

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Ohmura, Yamichi, Chiyuki Hayakawa, Takao Suzuki, and Kenji Tajima. "Annealing and Hydrogenation Behaviors of Electron-Beam Induced Defects in n-type Si." Japanese Journal of Applied Physics 38, Part 1, No. 7A (July 15, 1999): 4047–48. http://dx.doi.org/10.1143/jjap.38.4047.

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Chander, Subhash, and M. S. Dhaka. "Thermal annealing induced physical properties of electron beam vacuum evaporated CdZnTe thin films." Thin Solid Films 625 (March 2017): 131–37. http://dx.doi.org/10.1016/j.tsf.2017.01.052.

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Furuya, Kazuo, Masaki Takeguchi, and Kazutaka Mitsuishi. "Iron Nanostructures Fabricated by Electron Beam Induced Deposition and its Magnetic Properties." Solid State Phenomena 124-126 (June 2007): 139–42. http://dx.doi.org/10.4028/www.scientific.net/ssp.124-126.139.

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Electron beam induced deposition (EBID) was carried out with gas introduction systems attached to field emission scanning electron microscope (FE-SEM). Using iron carbonyl and ferrocene, three dimensional (3-D) antenna structures were fabricated in the range of 30-50 nm in diameter and 500-1000 nm in size. Post-deposition annealing of iron nanostructures resulted in the formation of crystalline alpha-iron and iron carbide phases. The iron concentration was controlled by the partial pressure of iron carbonyl and ferrocene. Electron holography observation with field emission transmission electron microscopy (FE-TEM) revealed that the remanent magnetic flux density Br of the nanostructures also depends on the iron concentration.

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Khalil, A. S. "Electron Beam-Irradiation-Induced Annealing of Nanoscale Defects Created by Heavy Ion Beam Bombardment of Indium Phosphide." Microscopy and Microanalysis 22, S3 (July 2016): 1488–89. http://dx.doi.org/10.1017/s143192761600828x.

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Koveshnikov, Sergei, Maxim Knyazev, and Oleg Soltanovich. "Generation, relaxation and annealing of Si/SiO2 charges induced by low-energy electron beam." Materials Science and Engineering: B 274 (December 2021): 115487. http://dx.doi.org/10.1016/j.mseb.2021.115487.

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Fang, Jing-Yue, Shi-Qiao Qin, Xue-Ao Zhang, Dong-Qing Liu, and Sheng-Li Chang. "Annealing effect of platinum-incorporated nanowires created by focused ion/electron-beam-induced deposition." Chinese Physics B 23, no. 8 (July 31, 2014): 088111. http://dx.doi.org/10.1088/1674-1056/23/8/088111.

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Pronin, Igor A., Igor A. Averin, Andrey A. Karmanov, Nadezhda D. Yakushova, Alexey S. Komolov, Eleonora F. Lazneva, Maxim M. Sychev, Vyacheslav A. Moshnikov, and Ghenadii Korotcenkov. "Control over the Surface Properties of Zinc Oxide Powders via Combining Mechanical, Electron Beam, and Thermal Processing." Nanomaterials 12, no. 11 (June 4, 2022): 1924. http://dx.doi.org/10.3390/nano12111924.

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The surface properties of zinc oxide powders prepared using mechanical activation, electron beam irradiation, and vacuum annealing, as well using combinations of these types of treatments, were studied using X-ray photoelectron spectroscopy. The structure of the obtained materials was studied by an X-ray diffraction technique and by scanning electron microscopy. We found that over five hours of grinding in an attritor, the size of nanocrystals decreases from 37 to 21 nm, and microdeformations increase from 0.3% to 0.6%. It was also found that a five-hour grinding treatment promoted formation of vacancies in the zinc sublattice at the surface and diffusion of Zn2+ cations into the bulk of the material. Irradiation of commercial zinc oxide powders with an electron beam with an energy of 0.9 MeV and a dose of 1 MGy induced breaking of Zn–O bonds, diffusion of interstitial zinc ions into the bulk, and oxygen atom escape from regular positions into the gas phase. A combined treatment of five hours of grinding and electron beam irradiation promoted accumulation of interstitial zinc ions at the surface of the material. Annealing of both initial and mechanically activated ZnO powders at temperatures up to 400 °C did not lead to a significant change in the properties of the samples. Upon exceeding the 400 °C annealing temperature the X-ray photoelectron spectra show almost identical atomic composition of the two types of materials, which is related to diffusion of interstitial zinc ions from the bulk of the material to the surface.

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Puydinger dos Santos, Marcos V., Murilo F. Velo, Renan D. Domingos, Yucheng Zhang, Xavier Maeder, Carlos Guerra-Nuñez, James P. Best, et al. "Annealing-Based Electrical Tuning of Cobalt–Carbon Deposits Grown by Focused-Electron-Beam-Induced Deposition." ACS Applied Materials & Interfaces 8, no. 47 (November 16, 2016): 32496–503. http://dx.doi.org/10.1021/acsami.6b12192.

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Ervin, Matthew H., Daniel Chang, Barbara Nichols, Alma Wickenden, John Barry, and John Melngailis. "Annealing of electron beam induced deposits of platinum from Pt(PF[sub 3])[sub 4]." Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures 25, no. 6 (2007): 2250. http://dx.doi.org/10.1116/1.2806978.

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Howitt, D. G., and A. B. Harker. "The oriented growth of anatase in thin films of amorphous titania." Journal of Materials Research 2, no. 2 (April 1987): 201–10. http://dx.doi.org/10.1557/jmr.1987.0201.

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The growth of an oriented anatase grain structure from the post-deposition annealing of amorphous reactive ion-beam-deposited thin films of titanium oxide has been demonstrated. The transformation has been observed directly by electron microscopy and the crystallization of the films occurs only when their thicknesses are greater than about 50 nm. Substrate effects were not found to be significant to the crystallization, which could also be induced by annealing freestanding films. The transformation processes can be described in terms of existing theories of crystal growth where the amorphous film is described as a supercooled liquid.

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Szkudlarek, Aleksandra, Alfredo Rodrigues Vaz, Yucheng Zhang, Andrzej Rudkowski, Czesław Kapusta, Rolf Erni, Stanislav Moshkalev, and Ivo Utke. "Formation of pure Cu nanocrystals upon post-growth annealing of Cu–C material obtained from focused electron beam induced deposition: comparison of different methods." Beilstein Journal of Nanotechnology 6 (July 13, 2015): 1508–17. http://dx.doi.org/10.3762/bjnano.6.156.

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In this paper we study in detail the post-growth annealing of a copper-containing material deposited with focused electron beam induced deposition (FEBID). The organometallic precursor Cu(II)(hfac)2 was used for deposition and the results were compared to that of compared to earlier experiments with (hfac)Cu(I)(VTMS) and (hfac)Cu(I)(DMB). Transmission electron microscopy revealed the deposition of amorphous material from Cu(II)(hfac)2. In contrast, as-deposited material from (hfac)Cu(I)(VTMS) and (hfac)Cu(I)(DMB) was nano-composite with Cu nanocrystals dispersed in a carbonaceous matrix. After annealing at around 150–200 °C all deposits showed the formation of pure Cu nanocrystals at the outer surface of the initial deposit due to the migration of Cu atoms from the carbonaceous matrix containing the elements carbon, oxygen, and fluorine. Post-irradiation of deposits with 200 keV electrons in a transmission electron microscope favored the formation of Cu nanocrystals within the carbonaceous matrix of freestanding rods and suppressed the formation on their surface. Electrical four-point measurements on FEBID lines from Cu(hfac)2 showed five orders of magnitude improvement in conductivity when being annealed conventionally and by laser-induced heating in the scanning electron microscope chamber.

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Wada, Toshimi, Toshihiko Kanayama, Shingo Ichimura, Yoshinobu Sugiyama, and Masanori Komuro. "Annealing Behavior of Irradiation-Induced Damage in an AlGaAs/GaAs Heterostructure by Low-Energy Electron Beam." Japanese Journal of Applied Physics 33, Part 1, No. 12B (December 30, 1994): 7228–31. http://dx.doi.org/10.1143/jjap.33.7228.

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Ohdaira, Keisuke, and Hideki Matsumura. "Liquid-phase explosive crystallization of electron-beam-evaporated a-Si films induced by flash lamp annealing." Journal of Crystal Growth 362 (January 2013): 149–52. http://dx.doi.org/10.1016/j.jcrysgro.2011.11.028.

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Bo-Xu, Zhang, Wang Zhong-Lie, Qi Li, P. J. Zhang, J. G. Zheng, L. C. Wang, and Du An-Yan. "High-resolution electron microscopy analysis of ion-beam induced annealing of MeV As+ ion-implanted silicon." Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 59-60 (July 1991): 434–38. http://dx.doi.org/10.1016/0168-583x(91)95254-b.

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Meldrum, A., L. A. Boatner, and R. C. Ewing. "Electron-irradiation-induced nucleation and growth in amorphous LaPO4, ScPO4, and zircon." Journal of Materials Research 12, no. 7 (July 1997): 1816–27. http://dx.doi.org/10.1557/jmr.1997.0250.

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Synthetic LaPO4, ScPO4, and crystalline natural zircon (ZrSiO4) from Mud Tanks, Australia were irradiated by 1.5 MeV Kr+ ions until complete amorphization occurred as indicated by the absence of electron-diffraction maxima. The resulting amorphous materials were subsequently irradiated by an 80 to 300 keV electron beam in the transmission electron microscope at temperatures between 130 and 800 K, and the resulting microstructural changes were monitored in situ. Thermal anneals in the range of 500 to 600 K were also conducted to compare the thermally induced microstructural development with that produced by the electron irradiations. Amorphous LaPO4 and ScPO4 annealed to form a randomly oriented polycrystalline assemblage of the same composition as the original material, but zircon recrystallized to ZrO2 (zirconia) + amorphous SiO2 for all beam energies and temperatures investigated. The rate of crystallization increased in the order: zircon, ScPO4, LaPO4. Submicrometer tracks of crystallites having a width equal to that of the electron beam could be “drawn” on the amorphous substrate. In contrast, thermal annealing resulted in epitaxial recrystallization from the thick edges of the TEM samples. Electron-irradiation-induced nucleation and growth in these materials can be explained by a combination of radiation-enhanced diffusion as a result of ionization processes and a strong thermodynamic driving force for crystallization. The structure of the amorphous orthophosphates may be less rigid than that of their silicate analogues because of the lower coordination across the PO4 tetrahedron, and thus a lower energy is required for reorientation and recrystallization. The more highly constrained monazite structure-type recovers at a lower electron dose than the zircon structure-type, consistent with recent models used to predict the crystalline-to-amorphous transition as a result of ion irradiation.

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Pelella, Aniello, Alessandro Grillo, Enver Faella, Filippo Giubileo, Francesca Urban, and Antonio Di Bartolomeo. "Molybdenum Disulfide Field Effect Transistors under Electron Beam Irradiation and External Electric Fields." Materials Proceedings 4, no. 1 (November 10, 2020): 25. http://dx.doi.org/10.3390/iocn2020-07807.

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In this work, monolayer molybdenum disulfide (MoS2) nanosheets, obtained via chemical vapor deposition onto SiO2/Si substrates, are exploited to fabricate field-effect transistors with n-type conduction, high on/off ratio, steep subthreshold slope and good mobility. We study their electric characteristics from 10−6 Torr to atmospheric air pressure. We show that the threshold voltage of the transistor increases with the growing pressure. Moreover, Schottky metal contacts in monolayer molybdenum disulfide (MoS2) field-effect transistors (FETs) are investigated under electron beam irradiation conditions. It is shown that the exposure of Ti/Au source/drain electrodes to an electron beam reduces the contact resistance and improves the transistor performance. It is shown that e-beam irradiation lowers the Schottky barrier at the contacts due to thermally induced atom diffusion and interfacial reactions. The study demonstrates that electron beam irradiation can be effectively used for contact improvement though local annealing. It is also demonstrated that the application of an external field by a metallic nanotip induces a field emission current, which can be modulated by the voltage applied to the Si substrate back-gate. Such a finding, that we attribute to gate-bias lowering of the MoS2 electron affinity, enables a new field-effect transistor based on field emission.

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Xia, Xinyi, Nahid Al-Mamun, Warywoba Daudi, Fan Ren, Aman Haque, and Stephen J. Pearton. "Ga+ Focused Ion Beam Damage in n-type Ga₂O₃and Its Recovery after Annealing Treatment." ECS Meeting Abstracts MA2022-02, no. 34 (October 9, 2022): 1245. http://dx.doi.org/10.1149/ma2022-02341245mtgabs.

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In this study, the focused ion beam (FIB) Ga+ irradiation damage on β-Ga2O3 Schottky diode structure under different ion energies were tested, and the effective recovery of diode characteristics after rapid thermal annealing (RTA) post-annealing were also studied. β-Ga2O3 based Schottky diodes have attracted increasing attention because of the prospects for use in next-generation high-power electronics. Focused ion beam (FIB) machining is one of the newest processing techniques, which is mainly used in semiconductor and chip manufacture and transmission electron microscopy (TEM) sample preparation. During FIB sample preparation, the energetic Ga ions are incident onto the sample to induce physical sputtering of the material, which in turn, modifies its chemical composition, crystallinity and electrical properties. It has been found in many studies that 20-30 nm amorphous layer can form on silicon after irradiation with 30 keV Ga ions. From our previous study, the FIB ion beam induced damages could cause significant degradation on diode on-resistance and turn-on voltage. Milling at lower energy has been used to reduce the electrical damage. However low energy milling is more time consuming and less precise. Short-time, high-temperature post-annealing treatments, such as RTA has been proved could remove the crystal damage. Thus, there is a great need to determine the maximal ion beam energy and post-annealing temperature for FIB without degrading diode characteristics. In this work, energies ranging from 2 keV to 30 keV were employed to mill off a part of Ga2O3 epi-layer and Schottky diodes were fabricated on milled surface. Forward IV characteristic shows less degradations with lower ion beam energies. For the diodes exposed to 2, 5, and 10 keV Ga+ ion beams exhibited significant recovery of diode on resistance and turn-on voltage after 300°C RTA annealing. For the diodes exposed to 30 keV Ga+ ion beams recovered significantly after 400 °C annealing. In conclusion, decreasing the FIB energy shows effective alleviations on the FIB damage, and post annealing treatment effectively recovered the damage from Ga+ implantation. This is the first time the thermal annealing treatment was performed for Ga2O3 Schottky diode recovering from FIB cutting, it is an effective and simple way to mitigate the degradation, especially for higher ion beam energies. This work could broaden the FIB’s usability and release tremendous potential as a specimen preparation and imaging tool in materials science applications. Figure 1

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Pablo-Navarro, Javier, Robert Winkler, Georg Haberfehlner, César Magén, Harald Plank, and José María De Teresa. "In situ real-time annealing of ultrathin vertical Fe nanowires grown by focused electron beam induced deposition." Acta Materialia 174 (August 2019): 379–86. http://dx.doi.org/10.1016/j.actamat.2019.05.035.

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Soloviev, Stanislav I., Kevin Matocha, Greg Dunne, and Zachary Stum. "Correlation between Thermal Oxide Breakdown and Defects in n-Type 4H-SiC Epitaxial Wafers." Materials Science Forum 600-603 (September 2008): 775–78. http://dx.doi.org/10.4028/www.scientific.net/msf.600-603.775.

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In this work, the correlation between thermal oxide breakdown and dislocations in n-type 4H-SiC epitaxial wafers has been investigated. Thermal oxide was grown by oxidation in N2O at 1250°C followed by annealing in NO atmosphere. The electron beam induced current (EBIC) technique was employed to find correlations between the electrically active defects in epitaxial layers and regions where the oxide breakdowns occurred. The test measurements of leakage currents in MOS devices were performed in order to correlate the leakage currents with number of defects in the epi-layer detected by EBIC technique.

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Auret, F. Danie, A. G. M. Das, C. Nyamhere, M. Hayes, and N. G. van der Berg. "Thermal Stability of Ti/Mo Schottky Contacts on p-Si and Defects Introduced in p-Si during Electron Beam Deposition of Ti/Mo." Solid State Phenomena 108-109 (December 2005): 561–66. http://dx.doi.org/10.4028/www.scientific.net/ssp.108-109.561.

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In this study we have investigated the thermal stability (in the range 100 oC - 900 oC) of defects introduced in p-Si by electron beam deposition (EBD) of Ti and Ti/Mo Schottky contacts. The depletion regions below these contacts were probed by conventional deep level transient spectroscopy (DLTS) as well as Laplace (high-resolution) DLTS (L-DLTS). We have chosen Ti as the Schottky contact because the barrier height of Ti/p-Si (0.53 eV) is close to that of TiSi2/p-Si (0.50 eV) that forms after annealing at 600 – 650 oC. The Mo was added on top of the Ti in order to prevent annealing degradation. These contacts were annealed in Ar at temperatures of up to 900 oC in 100 oC steps for half-hour periods. Current – voltage (I-V) and capacitance – voltage (C-V) measurements were used to monitor the quality of the Schottky contacts. DLTS was performed after each annealing cycle to monitor the presence of the EBD-induced defects and to obtain heir electronic properties. We have found that that the Ti/Mo contacts were superior to the Ti contacts. Their (Ti/Mo) barrier height after EBD was 0.52 eV and it gradually increased to 0.56 eV after annealing at 500 oC - 600oC and then dropped to 0.50 eV annealing at 700 oC. DLTS revealed that the main defects introduced during metallization are hole traps H(0.17), H(0.23), H(0.37) and H(0.49). Annealing at 350 oC introduced an additional hole trap H(0.39). After annealing at 550 oC all defects were removed from the depletion region.

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Takeda, Hiroaki, Han Joong Sang, Takashi Tateishi, Spela Kunej, Colin Leach, Robert Freer, Takuya Hoshina, and Takaaki Tsurumi. "Characterization of Grain Boundaries of Lead-Free Semiconducting Ceramics Using BaTiO₃-(Bi_1/2K_1/2)TiO₃ System." Key Engineering Materials 485 (July 2011): 241–44. http://dx.doi.org/10.4028/www.scientific.net/kem.485.241.

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BaTiO3–(Bi1/2K1/2)TiO3 (abbreviated as BT-BKT) solid solution ceramics, as a lead-free PTC (positive temperature coefficient of resistivity) thermistor material usable over 130°C, has been synthesized by sintering in N2 atmosphere and after annealing in air over 1200°C. In the BT-BKT ceramics with PTC property, the impedance/modulus spectroscopic plots have revealed that a third resistance-capacitance (RC) response besides grains and grain boundaries. Using the remote electron beam induced current (REBIC) configuration, imaging has revealed EBIC contrast consistent with the presence of negatively charged electrostatic grain boundary barriers in the BT-BKT semiconducting ceramics.

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Nagatomi, Takaharu, Tatsuya Nakao, and Yoko Fujimoto. "Application of focused ion-beam sampling for sidewall-roughness measurement of free-standing sub-μm objects by atomic force microscopy." Microscopy 69, no. 1 (January 15, 2020): 11–16. http://dx.doi.org/10.1093/jmicro/dfz108.

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Abstract In the present study, a free-standing object-sampling technique for microelectromechanical systems (MEMS) is developed to measure their sidewall surface roughnesses by atomic force microscopy (AFM). For this purpose, a conventional focused ion beam (FIB) sampling technique widely used for cross-sectional transmission electron microscope specimen preparation was applied. The sub-nm-order roughness parameters were quantitatively measured for sidewalls of Si-bridge test samples. The roughness parameters were compared before and after H2 annealing treatment, which induced smoothing of the surface by migration of the Si atoms. The reduction in the surface roughness by a factor of approximately one-third with 60-s H2 annealing was quantitatively evaluated by AFM. The present study confirms that the developed FIB–AFM technique is one potential approach for quantitatively evaluating the surface-roughness parameters on the oblique faces of free-standing objects in MEMS devices.

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Fang, Jingyue, Xinxing Li, Wenke Xie, and Kehui Sun. "A Novel Fabrication of Single Electron Transistor from Patterned Gold Nanoparticle Array Template-Prepared by Polystyrene Nanospheres." Nanomaterials 12, no. 18 (September 7, 2022): 3102. http://dx.doi.org/10.3390/nano12183102.

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In this paper, polystyrene microspheres were firstly prepared by seeded emulsion polymerization, and the uniform monolayer of polystyrene microspheres was prepared on the substrate by the dipping method. Then, polystyrene monolayer film was used as a mask and a low dimensional array structure of gold was prepared by bottom-up self-assembly process. After that, the method of solution etching and annealing was used, and the gold nanoparticle array was post-processed. As a result, gold nanoparticles were recrystallized, with an average diameter of about 50 nm. Subsequently, the semiconductor process was adopted, with focused ion beams induced deposition and electron beam evaporation, and single electron transistors were fabricated, based on self-assembled gold nanoparticles. Finally, the devices were fixed in a liquid helium cryostat and Coulomb blockade was observed at 320 mK. It is a novel fabrication of a single electron transistor based on gold nanoparticle array template and prepared with polystyrene nanospheres.

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Lavagne, S., C. Levade, and G. Vanderschaeve. "TEM in situ study of degradation mechanisms induced by temperature annealing and electron beam irradiation in a ZnSe/GaAs heterostructure." Materials Science and Engineering: B 128, no. 1-3 (March 2006): 1–6. http://dx.doi.org/10.1016/j.mseb.2005.07.023.

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Çetin, Mehmet Emin, Gökhan Polat, Mustafa Tekin, Ahmet Burçin Batibay, and Hasan Kotan. "Effect of Y addition on the structural transformation and thermal stability of Ti-22Al-25Nb alloy produced by mechanical alloying." Materials Testing 63, no. 7 (July 1, 2021): 599–605. http://dx.doi.org/10.1515/mt-2020-0099.

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Abstract In this study, a Ti-22Al-25Nb alloy with nanocrystalline structure was produced by high energy mechanical alloying (HEMA) and 1 at.-% yttrium was added as a thermal stabilizer. The as-milled samples were annealed at various temperatures up to 900 °C in a protective gas atmosphere, and the samples were allowed to cool to room temperature in the furnace. The phase transformations and microstructural changes as a function of the annealing temperatures and alloy compositions were studied using room- and high-temperature X-ray diffraction (XRD), focused ion beam microscopy (FIB), and scanning electron microscopy (SEM). The mechanical properties of the samples were interpreted based on the hardness results and their correlation with the microstructures. The results showed that the as-milled nanocrystalline structure of Ti-22Al-25Nb alloy increased from 3.4 nm to 350 nm after annealing at 800 °C due to the high driving force induced by the large grain boundary area. Consequently, the as-milled hardness of the Ti-22Al-25Nb alloy dropped from 7.63 ± 0.18 GPa to 5.37 ± 0.28 GPa. The grain size stability of the Ti-22Al-25Nb alloy after annealing at elevated temperature was ensured through the addition of yttrium. Thus, the grain size remained at the level of 125 nm, and the hardness value was maintained at around 6.98 ± 0.43 GPa after annealing at 800 °C.

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Kong, Mingdong, Bincheng Li, Chun Guo, Peng Zeng, Ming Wei, and Wenyan He. "The Optical Absorption and Photoluminescence Characteristics of Evaporated and IAD HfO2 Thin Films." Coatings 9, no. 5 (May 8, 2019): 307. http://dx.doi.org/10.3390/coatings9050307.

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HfO2 thin films are extensively applied in optical coatings and microelectronic devices. However, film defects, which are vital to the performance of the thin films, are still under intense investigation. In this work, the absorption, photoluminescence, and crystallization characteristics of HfO2 films prepared by electron-beam evaporation and ion-assisted deposition are investigated in detail. Experimental results showed that high-temperature thermal annealing in air resulted in a reduced absorption coefficient, an increased bandgap width, and an increased degree of crystallization. After thermal annealing, an absorption shoulder near 5.8 eV was caused by excitons in the films, which were independent of oxygen vacancy defects and crystallization. Under 6.4 eV (193 nm) laser excitation, the photoluminescence spectrum showed five emission peaks for HfO2 films both with and without thermal annealing. The emission peak near 4.4 eV was generated by the self-trapped exciton, and the peak near 4.0 eV was related to the OH group in the film. The oxygen vacancy defect-induced absorption of HfO2 films in a broad spectral range significantly increased when HfO2 film was re-annealed in Ar gas after first being annealed in air, while the photoluminescence spectrum showed no significant change, indicating that the emission peaks at 2.3, 2.8, and 3.4 eV were not related to oxygen vacancy defects.

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Luo, J. S., and G. K. Liu. "Microscopic effects of self-radiation damage in 244Cm-doped LuPO4 crystals." Journal of Materials Research 16, no. 2 (February 2001): 366–72. http://dx.doi.org/10.1557/jmr.2001.0056.

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Microscopic effects of self-radiation damage in 244Cm-doped LuPO4 crystals were examined with transmission electron microscopy. These LuPO4 crystals had been doped with 1 wt% 244Cm and exposed to a radiation dose as high as 5 × 1016 α-decay events/mg over 18 years. The microscopic analysis revealed dense arrays of individual defect clusters and numerous bubbles. Whereas, the defect clusters may be interpreted as residuals of alpha-recoil tracks, the bubbles likely resulted from the α-particles generated during the decay events. The bubbles were found to coalesce under electron beam irradiation. Despite the high accumulated dose over the 18 years, the samples exhibited sharp diffraction patterns and periodic lattice spacings. This finding indicated that the samples remained largely crystalline and that the radiation-induced lattice damage was recovered at a rate comparable to that of damage production. This high recoverability is discussed with respect of various annealing processes that may have occurred in the samples.

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Lu, Jinggang, George A. Rozgonyi, James Rand, and Ralf Jonczyk. "EBIC Study of Electrical Activity of Stacking Faults in Multicrystalline Sheet Silicon." Solid State Phenomena 108-109 (December 2005): 627–30. http://dx.doi.org/10.4028/www.scientific.net/ssp.108-109.627.

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The electrical activity of stacking faults (SFs) in multicrystalline sheet silicon has been examined by correlating EBIC(electron beam induced current), preferential defect etching, and microwave photo-conductance decay (PCD) lifetime measurements. Following a three hour 1060 0C annealing the interstitial oxygen concentration decreased from 14 to 4.5 x 1017 cm-3, during which time a high density of SFs were generated in the center of individual large grains. Subsequent EBIC contrast variation within individual large grains was correlated with the local SF density revealed by preferential etching. In addition, a more quantitative intra-grain lifetime was obtained from high spatial resolution PCD measurements. It was found that an SF density of 1 to 2 x 106 cm-2 produces a lifetime limitation in sheet silicon which corresponds to a recombination lifetime of ~2 µs.

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Khoroshko, Ekaterina, Andrey Filippov, Sergei Tarasov, Nikolay Shamarin, Evgeny Moskvichev, Sergei Fortuna, Dmitry V. Lychagin, and Evgeny Kolubaev. "Strength and Ductility Improvement through Thermomechanical Treatment of Wire-Feed Electron Beam Additive Manufactured Low Stacking Fault Energy (SFE) Aluminum Bronze." Metals 10, no. 12 (November 24, 2020): 1568. http://dx.doi.org/10.3390/met10121568.

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An as-cast macrostructure of electron beam additively manufactured metallic materials was represented by coarse columnar grains whose axes were inclined at 25° with respect to the substrate’s plane. One part of the as-grown samples was annealed to form a coarse grain microstructure while the other part was pre-deformed by forging and then annealed what allowed obtaining recrystallized microstructures with small grains and multiple annealing twin boundaries. This sample showed both high strength and plasticity during the tensile tests. These tensile tests demonstrated also two-stage stress-strain curves as depended on their strain hardening rates. High and low strain hardening rates corresponded to a twinning-dominated deformation at stage II and dislocation-base deformation at stage III. A submicron size strain-induced grain-subgrain microstructure was formed in the vicinity of a necked zone as a result of combined twinning/dislocation grain refining.

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P, Ragesh Kumar T., Paul Weirich, Lukas Hrachowina, Marc Hanefeld, Ragnar Bjornsson, Helgi Rafn Hrodmarsson, Sven Barth, D. Howard Fairbrother, Michael Huth, and Oddur Ingólfsson. "Electron interactions with the heteronuclear carbonyl precursor H2FeRu3(CO)13 and comparison with HFeCo3(CO)12: from fundamental gas phase and surface science studies to focused electron beam induced deposition." Beilstein Journal of Nanotechnology 9 (February 14, 2018): 555–79. http://dx.doi.org/10.3762/bjnano.9.53.

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In the current contribution we present a comprehensive study on the heteronuclear carbonyl complex H2FeRu3(CO)13 covering its low energy electron induced fragmentation in the gas phase through dissociative electron attachment (DEA) and dissociative ionization (DI), its decomposition when adsorbed on a surface under controlled ultrahigh vacuum (UHV) conditions and exposed to irradiation with 500 eV electrons, and its performance in focused electron beam induced deposition (FEBID) at room temperature under HV conditions. The performance of this precursor in FEBID is poor, resulting in maximum metal content of 26 atom % under optimized conditions. Furthermore, the Ru/Fe ratio in the FEBID deposit (≈3.5) is higher than the 3:1 ratio predicted. This is somewhat surprising as in recent FEBID studies on a structurally similar bimetallic precursor, HFeCo3(CO)12, metal contents of about 80 atom % is achievable on a routine basis and the deposits are found to maintain the initial Co/Fe ratio. Low temperature (≈213 K) surface science studies on thin films of H2FeRu3(CO)13 demonstrate that electron stimulated decomposition leads to significant CO desorption (average of 8–9 CO groups per molecule) to form partially decarbonylated intermediates. However, once formed these intermediates are largely unaffected by either further electron irradiation or annealing to room temperature, with a predicted metal content similar to what is observed in FEBID. Furthermore, gas phase experiments indicate formation of Fe(CO)4 from H2FeRu3(CO)13 upon low energy electron interaction. This fragment could desorb at room temperature under high vacuum conditions, which may explain the slight increase in the Ru/Fe ratio of deposits in FEBID. With the combination of gas phase experiments, surface science studies and actual FEBID experiments, we can offer new insights into the low energy electron induced decomposition of this precursor and how this is reflected in the relatively poor performance of H2FeRu3(CO)13 as compared to the structurally similar HFeCo3(CO)12.

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Mateus, Rodrigo, Patricia A. Carvalho, Nuno Franco, Luís C. Alves, Micaela Fonseca, and Eduardo Alves. "Carbon Deposition on Beryllium Substrates and Subsequent Delamination." Materials Science Forum 730-732 (November 2012): 179–84. http://dx.doi.org/10.4028/www.scientific.net/msf.730-732.179.

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Beryllium and carbon are foreseen as materials for plasma facing components of future fusion devices. Erosion, re-deposition and thermal annealing events arising from heat-loads during reactor operation will produce mixed material layers and compounds on the plasma facing surfaces, leading to changes in the material properties. In order to mimic the erosion/deposition and compound formation processes, carbon layers have been evaporated onto beryllium plates and annealed in the 373 to 1073 K range for 90 min. Ion beam measurements revealed a smooth beryllium and carbon interdiffusion at the samples interface up to 773 K. A carbide formation reaction front became apparent for higher temperatures in scanning electron microscopy observations, with the volume fraction of Be2C crystals resulting also evident in X-ray diffraction patterns. The annealing route induced delamination of large surface areas of the samples through telephone cords blistering, attributed to strain energy release. At 973 and 1073 K, cracking occurred preferentially along the blisters boundaries and evolved in time, leading to their final removal. This fracture behaviour seems caused by the different thermal expansion coefficients of the phases. The superficial films remain unchanged at lower temperatures. The results prove that the compound formation promotes by itself the occurrence of dust emission events in tokamaks.

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Miyazaki, S., T. Okumura, Y. Miura, and K. Hirose. "Inhomogeneous Reaction between Epitaxial Al and Si(111) Revealed by Scanning Internal Photoemission Microscopy (IPEM)." Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 378–79. http://dx.doi.org/10.1017/s0424820100164350.

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Aluminum is one of the most important materials for the Si LSI metallization. An epitaxial growth of Al films on Si can be achieved since the lattice constant ratio between Al and Si is approximately given by 3 to 4. It is expected that epitaxial Al films are highly stable against thermal annealing. However, epitaxial-Al/Si contacts have sometimes shown a significant change in Schottky barrier height (SBH) and interface structure upon annealing. The objective of this paper is to clarify the relation between the SBH inhomogeneity and the thermally induced reaction between Al and Si through grain boundaries. The microscopic SBH distribution was measured by using scanning internal- photoemission microscopy (IPEM).Epitaxial Al layers were deposited on n-Si(l11) by electron beam evaporation at substrate temperatures of 220°C and 250°C. In the as-deposited state, the Al film fabricated at 220°C consisted mainly of “type-A”- and partially of “type-”"-orientated interfaces (referred to as a mixed phase: MP-AS), while that deposited at 250°C consisted only of “type-B” (referred to as a single phase: SP-AS). The samples were annealed for 1 hour at temperatures between 450-550°C and then quenched.

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40

Wu, Weihua, Bo Shen, Jiwei Zhai, Sannian Song, and Zhitang Song. "In-situ investigation on the crystallization property and microstructure evolution induced by thermal annealing and electron beam irradiation of titanium antimony thin film." Applied Physics Letters 115, no. 2 (July 8, 2019): 021903. http://dx.doi.org/10.1063/1.5109380.

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41

Zhang, Jing, De Gui Sun, Xiu Hua Fu, and Dong Mei Liu. "Study and Fabrication of Multi-Band Filter Film on ZnS Substrate." Key Engineering Materials 552 (May 2013): 147–51. http://dx.doi.org/10.4028/www.scientific.net/kem.552.147.

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In order to satisfy the special requirements of IR optical instrument, multi-band filter film on the substrate of ZnS is deposited by adopting electron beam vacuum depositing method with the ion assistant deposition technology. At incident angle of 0°～25°, 660nm high reflection and 1064nm and 3～5μm high transmission are realized. ZnS and YbF3 are selected as the high and low refractive index materials, and the film structure prepared easily is getting by optimizing the film system design curve ceaselessly. The precision of thickness control has been improved by adjusting film process parameters and improving film thickness control methods. The adhesion and firmness of film and substrate has been increased by pre-coating and mixed evaporation technology, and the laser induced damage threshold of film has been improved with vacuum annealing. The deposited film can endure the environmental tests such as rain pour, salt fog, and high and low temperature etc, and meet its practical requirement.

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42

Yamamoto, Hiroki, Guy Dawson, Takahiro Kozawa, and Alex P. G. Robinson. "Lamellar Orientation of a Block Copolymer via an Electron-Beam Induced Polarity Switch in a Nitrophenyl Self-Assembled Monolayer or Si Etching Treatments." Quantum Beam Science 4, no. 2 (March 27, 2020): 19. http://dx.doi.org/10.3390/qubs4020019.

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Directed self-assembly (DSA) was investigated on self-assembled monolayers (SAMs) chemically modified by electron beam (EB) irradiation, which is composed of 6-(4-nitrophenoxy) hexane-1-thiol (NPHT). Irradiating a NPHT by EB could successfully induce the orientation and selective patterning of block copolymer domains. We clarified that spatially-selective lamellar orientations of polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) could be achieved by a change of an underlying SAM. The change of an underlying SAM is composed of the transition of an NO2 group to an NH2 group, which is induced by EB. The modification in the polarity of different regions of the SAM with EB lithography controlled the lamellar orientation of PS-b-PMMA. The reduction of the NPHT SAM plays an important role in the orientation of block copolymer. This method might significantly simplify block copolymer DSA processes when it is compared to the conventional DSA process. By investigating the lamellae orientation with EB, it is clarified that only suitable annealing temperatures and irradiation doses lead to the vertical orientation. We also fabricated pre-patterned Si substrates by EB lithographic patterning and reactive ion etching (RIE). DSA onto such pre-patterned Si substrates was proven to be successful for subdivision of the lithographic patterns into line and space patterns.

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43

Morilla, Y., J. García López, Gábor Battistig, J. L. Cantin, Juan Carlos Cheang-Wong, Hans Jürgen von Bardeleben, and M. A. Respaldiza. "RBS-Channeling and EPR Studies of Damage in 2 MeV Al²⁺-Implanted 6H-SiC Substrates." Materials Science Forum 483-485 (May 2005): 291–94. http://dx.doi.org/10.4028/www.scientific.net/msf.483-485.291.

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6H-SiC single crystalline substrates were implanted at room temperature with 2 MeV Al2+ ions to fluences from 2×1014 Al2+ cm-2 to 7×1014 Al2+ cm-2 and with different current densities (from 6.6 to 33×1010 Al2+ cm-2 s-1). The depth profile of the damage induced by the Al2+ ions was determined by Backscattering Spectrometry in channeling geometry (BS/C) with a 3.5 MeV He2+ beam. The BS/C spectra were evaluated using the RBX code. The samples were subsequently annealed at 1100°C in N2 for one hour, in order to analyze their structural recovery by BS/C and the amount of the remaining defects by means of Electron Paramagnetic Resonance (EPR). The results from the BS/C spectra corresponding to the as-implanted samples indicate that the damage depends strongly on the total fluence but also, although to a lesser extent, on the beam current density. The BS/C measurements reveal that all the samples, except the one implanted with the highest fluence, recover completely their original crystalline structure after the annealing. Furthermore the angular anisotropy of the EPR spectra indicates that the implanted region recovered a good crystallinity, although some residual defects were observed.

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44

Martín, Gemma, Lluís López-Conesa, Daniel del Pozo, Quim Portillo, George Doundoulakis, Alexandros Georgakilas, Sònia Estradé, and Francesca Peiró. "Precessed electron diffraction study of defects and strain in GaN nanowires fabricated by top-down etching." Applied Physics Letters 121, no. 8 (August 22, 2022): 082104. http://dx.doi.org/10.1063/5.0101908.

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Gallium nitride (GaN) nanowires (NWs) have been fabricated by top-down etching from GaN heteroepitaxial films, which provides an accurate control of their position and dimensions. However, these NWs contain, similar to the initial GaN films, high density of structural defects such as threading dislocations (TDs). In this work, different strategies to reduce the density of defects along the NWs have been compared based on two different wet etching approaches followed by a rapid thermal annealing (RTA) at 750 °C. The addition of a 30 nm SiNx coating is also explored. The defects and strain/stress along the NWs have been studied by high resolution transmission electron microscopy, diffraction contrast imaging in two-beam conditions and 4D STEM, as well as strain maps calculated from scanning precession electron diffraction measurements. RTA reduced the density of TDs at the middle of GaN NWs with bare surfaces by approximately 25%. The reduction increased to approximately 70% by RTA of GaN NWs with surfaces coated by amorphous SiNx, which is attributed to enhancement of dislocation movements by stresses induced from differential thermal expansion of GaN and SiNx. These results suggest a process route that, if optimized and combined with reduction of NW diameter, could establish etching as an efficient fabrication method for high crystal quality GaN NWs.

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45

Szkudlarek, Aleksandra, Alfredo Rodrigues Vaz, Yucheng Zhang, Andrzej Rudkowski, Czesław Kapusta, Rolf Erni, Stanislav Moshkalev, and Ivo Utke. "Correction: Formation of pure Cu nanocrystals upon post-growth annealing of Cu–C material obtained from focused electron beam induced deposition: comparison of different methods." Beilstein Journal of Nanotechnology 6 (September 21, 2015): 1935–36. http://dx.doi.org/10.3762/bjnano.6.196.

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46

Wu, Tai-Sing, Leng-You Syu, Shih-Chang Weng, Horng-Tay Jeng, Shih-Lin Chang, and Yun-Liang Soo. "Defect engineering by synchrotron radiation X-rays in CeO2 nanocrystals." Journal of Synchrotron Radiation 25, no. 5 (August 2, 2018): 1395–99. http://dx.doi.org/10.1107/s1600577518008184.

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This work reports an unconventional defect engineering approach using synchrotron-radiation-based X-rays on ceria nanocrystal catalysts of particle sizes 4.4–10.6 nm. The generation of a large number of oxygen-vacancy defects (OVDs), and therefore an effective reduction of cations, has been found in CeO2 catalytic materials bombarded by high-intensity synchrotron X-ray beams of beam size 1.5 mm × 0.5 mm, photon energies of 5.5–7.8 keV and photon fluxes up to 1.53 × 1012 photons s−1. The experimentally observed cation reduction was theoretically explained by a first-principles formation-energy calculation for oxygen vacancy defects. The results clearly indicate that OVD formation is mainly a result of X-ray-excited core holes that give rise to valence holes through electron down conversion in the material. Thermal annealing and subvalent Y-doping were also employed to modulate the efficiency of oxygen escape, providing extra control on the X-ray-induced OVD generating process. Both the core-hole-dominated bond breaking and oxygen escape mechanisms play pivotal roles for efficient OVD formation. This X-ray irradiation approach, as an alternative defect engineering method, can be applied to a wide variety of nanostructured materials for physical-property modification.

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47

Puydinger dos Santos, Marcos Vinicius, Aleksandra Szkudlarek, Artur Rydosz, Carlos Guerra-Nuñez, Fanny Béron, Kleber Roberto Pirota, Stanislav Moshkalev, José Alexandre Diniz, and Ivo Utke. "Comparative study of post-growth annealing of Cu(hfac)2, Co2(CO)8 and Me2Au(acac) metal precursors deposited by FEBID." Beilstein Journal of Nanotechnology 9 (January 9, 2018): 91–101. http://dx.doi.org/10.3762/bjnano.9.11.

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Non-noble metals, such as Cu and Co, as well as noble metals, such as Au, can be used in a number modern technological applications, which include advanced scanning-probe systems, magnetic memory and storage, ferroelectric tunnel junction memristors, metal interconnects for high performance integrated circuits in microelectronics and nano-optics applications, especially in the areas of plasmonics and metamaterials. Focused-electron-beam-induced deposition (FEBID) is a maskless direct-write tool capable of defining 3-dimensional metal deposits at nanometre scale for above applications. However, codeposition of organic ligands when using organometallic precursors is a typical problem that limits FEBID of pure metal nanostructures. In this work, we present a comparative study using a post-growth annealing protocol at 100, 200, and 300 °C under high vacuum on deposits obtained from Co2(CO)8, Cu(II)(hfac)2, and Me2Au(acac) to study improvements on composition and electrical conductivity. Although the as-deposited material was similar for all precursors, metal grains embedded in a carbonaceous matrix, the post-growth annealing results differed. Cu-containing deposits showed the formation of pure Cu nanocrystals at the outer surface of the initial deposit for temperatures above 100 °C, due to the migration of Cu atoms from the carbonaceous matrix containing carbon, oxygen, and fluorine atoms. The average size of the Cu crystals doubles between 100 and 300 °C of annealing temperature, while the composition remains constant. In contrast, for Co-containing deposits oxygen release was observed upon annealing, while the carbon content remained approximately constant; the cobalt atoms coalesced to form a metallic film. The as-deposited Au-containing material shows subnanometric grains that coalesce at 100 °C, maintaining the same average size at annealing temperatures up to 300 °C. Raman analysis suggests that the amorphous carbonaceous matrix of the as-written Co, Cu and Au deposits turned into nanocrystalline graphite with comparable crystal sizes of 12–14 nm at 300 °C annealing temperature. However, we observed a more effective formation of graphite clusters in Co- than in Cu- and Au-containing deposits. The graphitisation has a minor influence on the electrical conductivity improvements of Co–C deposits, which is attributed to the high as-deposited Co content and the related metal grain percolation. On the contrary, electrical conductivity improvements by factors of 30 and 12 for, respectively, Cu–C and Au–C deposits with low metal content are mainly attributed to the graphitisation. This relatively simple vacuum-based post-growth annealing protocol may be useful for other precursors as it proved to be efficient in reliably tuning the electrical properties of as-deposited FEBID materials. Finally, a H2-assisted gold purification protocol is demonstrated at temperatures around 300 °C by fully removing the carbon matrix and drastically reducing the electrical resistance of the deposit.

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48

Kaindl, Reinhard, Bernhard C. Bayer, Roland Resel, Thomas Müller, Viera Skakalova, Gerlinde Habler, Rainer Abart, et al. "Growth, structure and stability of sputter-deposited MoS2 thin films." Beilstein Journal of Nanotechnology 8 (May 22, 2017): 1115–26. http://dx.doi.org/10.3762/bjnano.8.113.

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Molybdenum disulphide (MoS2) thin films have received increasing interest as device-active layers in low-dimensional electronics and also as novel catalysts in electrochemical processes such as the hydrogen evolution reaction (HER) in electrochemical water splitting. For both types of applications, industrially scalable fabrication methods with good control over the MoS2 film properties are crucial. Here, we investigate scalable physical vapour deposition (PVD) of MoS2 films by magnetron sputtering. MoS2 films with thicknesses from ≈10 to ≈1000 nm were deposited on SiO2/Si and reticulated vitreous carbon (RVC) substrates. Samples deposited at room temperature (RT) and at 400 °C were compared. The deposited MoS2 was characterized by macro- and microscopic X-ray, electron beam and light scattering, scanning and spectroscopic methods as well as electrical device characterization. We find that room-temperature-deposited MoS2 films are amorphous, of smooth surface morphology and easily degraded upon moderate laser-induced annealing in ambient conditions. In contrast, films deposited at 400 °C are nano-crystalline, show a nano-grained surface morphology and are comparatively stable against laser-induced degradation. Interestingly, results from electrical transport measurements indicate an unexpected metallic-like conduction character of the studied PVD MoS2 films, independent of deposition temperature. Possible reasons for these unusual electrical properties of our PVD MoS2 thin films are discussed. A potential application for such conductive nanostructured MoS2 films could be as catalytically active electrodes in (photo-)electrocatalysis and initial electrochemical measurements suggest directions for future work on our PVD MoS2 films.

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Gromov, V. E., Yu A. Rubannikova, S. V. Konovalov, K. A. Osintsev, and S. V. Vorob’ev. "Generation of increased mechanical properties of Cantor highentropy alloy." Izvestiya. Ferrous Metallurgy 64, no. 8 (September 2, 2021): 599–605. http://dx.doi.org/10.17073/0368-0797-2021-8-599-605.

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The article considers a brief review of the last years of Russian and foreign research on the possibilities of improving mechanical properties of the Cantor quinary highentropy alloy (HEA) with diﬀerent phase composition in wide temperature range. The alloy, one of the frst created equimolar HEAs with FCC structure, needs mechanical properties improvement in accordance with possible felds of application in spite of its high impact toughness and increased creep resistance. It has been noted that bimodal distribution of the grains by sizes under severe plastic torsional strain at high pressure of 7.8 GPa of cast alloy and subsequent shorttime annealing at 873 and 973 K can change strength and plastic properties. Nanodimensional scale of the grains surrounded by amorphous envelope has been obtained for HEA produced by the method of magnetron sputtering and subsequent annealing at 573 K. In such a twophase alloy nanohardness amounted to 9.44 GPa and elasticity modulus – to 183 GPa. Using plasticity eﬀect induced by phase transformation in (CrMnFeCoNi)50Fe50 alloy obtained by the method of laser additive technology the ultimate strength of 415 – 470 MPa has been reached at high level of plasticity up to 77 %. It has been ensured by FCC → BCC diﬀusionless transformation. It is shown that diﬀerence in mechanisms of plastic strain of cast alloy at 77 K and 293 K (dislocation glide and twinning) determines a combination of increased “strengthplasticity” properties. Samples for generation of twins prestrained at 77 K exhibit increased strength and plasticity under subsequent loading at 293 K in comparison with the unstrained ones. For HEA obtained by laser additive technology this way of increasing properties is also true. The way of improving mechanical properties at the expense of electron beam processing is noted. The attention is paid to the necessity of taking into account the role of entropy, crystal lattice distortions, shortrange order, weak diﬀusion and “cocktail” eﬀect in the analysis of mechanical properties.

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50

Volkova, Kseniia, Julia Heupel, Sergei Trofimov, Fridtjof Betz, Rémi Colom, Rowan W. MacQueen, Sapida Akhundzada, et al. "Optical and Spin Properties of NV Center Ensembles in Diamond Nano-Pillars." Nanomaterials 12, no. 9 (April 29, 2022): 1516. http://dx.doi.org/10.3390/nano12091516.

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Nitrogen-vacancy (NV) color centers in diamond are excellent quantum sensors possessing high sensitivity and nano-scale spatial resolution. Their integration in photonic structures is often desired, since it leads to an increased photon emission and also allows the realization of solid-state quantum technology architectures. Here, we report the fabrication of diamond nano-pillars with diameters up to 1000 nm by electron beam lithography and inductively coupled plasma reactive ion etching in nitrogen-rich diamonds (type Ib) with [100] and [111] crystal orientations. The NV centers were created by keV-He ion bombardment and subsequent annealing, and we estimate an average number of NVs per pillar to be 4300 ± 300 and 520 ± 120 for the [100] and [111] samples, respectively. Lifetime measurements of the NVs’ excited state showed two time constants with average values of τ1 ≈ 2 ns and τ2 ≈ 8 ns, which are shorter as compared to a single color center in a bulk crystal (τ ≈ 10 ns). This is probably due to a coupling between the NVs as well as due to interaction with bombardment-induced defects and substitutional nitrogen (P1 centers). Optically detected magnetic resonance measurements revealed a contrast of about 5% and average coherence and relaxation times of T2 [100] = 420 ± 40 ns, T2 [111] = 560 ± 50 ns, and T1 [100] = 162 ± 11 μs, T1 [111] = 174 ± 24 μs. These pillars could find an application for scanning probe magnetic field imaging.

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Journal articles on the topic 'Electron-Beam-Induced Annealing'

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