Electron and Ion Beam-Enhanced Adhesion

1983 ◽  
Vol 25 ◽  
Author(s):  
I.V. Mitchell ◽  
J.S. Williams ◽  
D.K. Sood ◽  
K.T. Short ◽  
S. Johnson ◽  
...  

ABSTRACTHelium ions of 2 MeV energy and electrons of 5 to 30 keV energy have been used to irradiate a variety of thin (10–330 nm) metal films after deposition on semiconductor and insulator substrates. Dose thresholds for increased adhesion were found following irradiation with either type of particle. It is argued that the stronger bonding arises from an electronic, rather than a collisional, process. Representative results are presented and discussed within the framework of a recent model for heavy ion-induced effects.

Author(s):  
Charles W. Allen ◽  
Robert C. Birtcher

The uranium silicides, including U3Si, are under study as candidate low enrichment nuclear fuels. Ion beam simulations of the in-reactor behavior of such materials are performed because a similar damage structure can be produced in hours by energetic heavy ions which requires years in actual reactor tests. This contribution treats one aspect of the microstructural behavior of U3Si under high energy electron irradiation and low dose energetic heavy ion irradiation and is based on in situ experiments, performed at the HVEM-Tandem User Facility at Argonne National Laboratory. This Facility interfaces a 2 MV Tandem ion accelerator and a 0.6 MV ion implanter to a 1.2 MeV AEI high voltage electron microscope, which allows a wide variety of in situ ion beam experiments to be performed with simultaneous irradiation and electron microscopy or diffraction.At elevated temperatures, U3Si exhibits the ordered AuCu3 structure. On cooling below 1058 K, the intermetallic transforms, evidently martensitically, to a body-centered tetragonal structure (alternatively, the structure may be described as face-centered tetragonal, which would be fcc except for a 1 pet tetragonal distortion). Mechanical twinning accompanies the transformation; however, diferences between electron diffraction patterns from twinned and non-twinned martensite plates could not be distinguished.


Author(s):  
C. Rue ◽  
S. Herschbein ◽  
C. Scrudato ◽  
L. Fischer ◽  
A. Shore

Abstract The efficiency of Gas-Assisted Etching (GAE) and depositions performed using the Focused Ion Beam (FIB) technique is subject to numerous factors. Besides the wellknown primary parameters recommended by the FIB manufacturer (pixel spacing, dwell time, and gas pressures), certain secondary factors can also have a pronounced effect on the quality of these gas-assisted FIB operations. The position of the gas delivery nozzle during XeF2 mills on silicon is examined and was found to affect both the milling speed and the texture on the floor of the FIB trench. Limitations arising from the memory capacity of the FIB computer can also influence process times and trench quality. Exposing the FIB vacuum chamber to TMCTS during SiO2 depositions is found to temporarily impede the performance of subsequent tungsten depositions, especially following heavy or prolonged TMCTS exposure. A delay period may be required to achieve optimal tungsten depositions following TMCTS use. Finally, the focusing conditions of the ion beam are found to have a significant impact on the resistance of FIB-deposited metal films. This effect is attributed to partial milling of the deposition film due to the intense current density of the collimated ion beam. The resistances of metal depositions performed with intentionally defocused ion beams were found to be lower than those performed with focused beams.


1995 ◽  
Author(s):  
A. Fujisawa ◽  
A. Ouroua ◽  
J.W. Heard ◽  
T.P. Crowley ◽  
P.M. Schoch ◽  
...  

1997 ◽  
Vol 4 (5) ◽  
pp. 1357-1361 ◽  
Author(s):  
A. Fujisawa ◽  
H. Iguchi ◽  
S. Lee ◽  
T. P. Crowley ◽  
Y. Hamada ◽  
...  

Author(s):  
S. Gerardin ◽  
M. Bagatin ◽  
A. Paccagnella ◽  
S. Beltrami ◽  
A. Costantino ◽  
...  

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Roman Sherrod ◽  
Eric C. O’Quinn ◽  
Igor M. Gussev ◽  
Cale Overstreet ◽  
Joerg Neuefeind ◽  
...  

AbstractThe structural response of Dy2TiO5 oxide under swift heavy ion irradiation (2.2 GeV Au ions) was studied over a range of structural length scales utilizing neutron total scattering experiments. Refinement of diffraction data confirms that the long-range orthorhombic structure is susceptible to ion beam-induced amorphization with limited crystalline fraction remaining after irradiation to 8 × 1012 ions/cm2. In contrast, the local atomic arrangement, examined through pair distribution function analysis, shows only subtle changes after irradiation and is still described best by the original orthorhombic structural model. A comparison to Dy2Ti2O7 pyrochlore oxide under the same irradiation conditions reveals a different behavior: while the dysprosium titanate pyrochlore is more radiation resistant over the long-range with smaller degree of amorphization as compared to Dy2TiO5, the former involves more local atomic rearrangements, best described by a pyrochlore-to-weberite-type transformation. These results highlight the importance of short-range and medium-range order analysis for a comprehensive description of radiation behavior.


BMJ Open ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. e046043
Author(s):  
Pengtao Li ◽  
Jialing Wang ◽  
Aximujiang Axier ◽  
Kai Zhou ◽  
Jingwei Yun ◽  
...  

IntroductionCraniopharyngioma is the most challenging to treat brain tumour with high recurrence rates, which can be effectively reduced by adjuvant radiotherapy. In recent years, proton therapy (PT), with its physical properties of heavy ion beam, that is, Prague peak phenomenon, has been more frequently used in patients with craniopharyngioma. Compared with conventional X-ray beam radiotherapy, PT can reduce the damage to normal tissues and enlarge the damage to tumours. Some studies have shown that PT has advantages in the treatment of craniopharyngioma in adults. However, the optimal management of craniopharyngioma remains controversial. The purpose of this study was to evaluate the efficacy and safety of PT for craniopharyngioma in adults.Methods and analysisWe will search six databases (MEDLINE, EMBASE, Web of Science, the Cochrane Library, Amed, Scopus), clinical research registration websites and grey literature, aiming to identify randomised controlled trials (RCTs) on PT for craniopharyngioma in adults between 1 January 1954 and 28 September 2021. In the RCTs, PT will be used as the intervention group, and conventional X-ray beam radiotherapy will be used as the comparator group. Tumour recurrence and survival will be the primary outcome, and treatment-related toxicity will be the secondary outcome. The study selection, data extraction, bias risk and quality evaluation will be operated by two to four researchers independently. We will use Review Manager V.5.2 (RevMan V.5.2) for data analysis. If there is significant heterogeneity, we will identify the source of heterogeneity by subgroup analysis.Ethics and disseminationOur study is based on existing RCTs and does not require ethical approval. The results of the study will be published in a peer-reviewed journal or at a related conference.PROSPERO registration numberCRD42020200909.


2005 ◽  
Vol 908 ◽  
Author(s):  
Gary A. Glass ◽  
Bibhudutta Rout ◽  
Alexander D. Dymnikov ◽  
Elia V. Eschenazi ◽  
Richard Greco ◽  
...  

AbstractAn overview of the present state of high energy focused ion beam (HEFIB) system technology, nanoprobe system design and specific ion beam writing applications will be presented. In particular, the combination of P-beam, heavy-ion writing and ion implantation to produce microstructures in resists and silicon will be demonstrated.Heretofore, the development of HEFIB technology worldwide has progressed through a series of developments at independent research facilities, each having relatively narrow and mostly isolated, research purposes. However, a complete, versatile HEFIB nanoprobe system capable of both analysis and modification will require the combination of several component systems, each with specialized technology, and significant advances in the design of a complete system can only be expected from an effort that includes a coordinated development of the component parts.


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