Abstract
Ion-surface collision studies are carried out with small deuterated hydrocarbon cations i.e. CDx + with x = 2-4 colliding with fusion relevant Beryllium (Be) thin films with ions incident energy as low as 0 eV and as high as Ein = 100 eV. Be films are coated on stainless steel surface by the technique of Thermionic Vacuum Arc (TVA); a novel thin film deposition method with primary as well distinguished characteristic of control of ion flux and respective dose towards the substrate. Prior to scattering, methane-d4 99 atom % D is ionized by electron impact and ions are mass and energy analyzed. Ionization and collisions are performed in ultra high vacuum conditions. In these kinds of collision experiments, we have recorded secondary ion mass spectra and plotted respective incident energy resolved abundances of secondary product ions. Relative abundances in percentage of total secondary ions are plotted and it is observed that such beryllium films can accumulate charged hydrocarbon layers as surface adsorbates. These self assembled layers play a primary role in surface-scattering of primary ions. Moreover, it is seen that bond dissociation energy in lighter hydrocarbons is higher than that for heavier species and shows primarily that the deuterium atoms are loosely bounded to carbon atoms in heavier hydrocarbons than in lighter ones.
Highlights
Study of reactive collisions of ions with surfaces is the area accelerated in last few years towards characterizing gaseous molecular ions and nature of the surfaces
Considerable interests are taken to study physical sputtering as well chemical sputtering caused by colliding slow ions with hyper thermal energy range and the processes like Surface Induced Dissociation (SID), Charge Exchange Reactions (CER) and reflection properties have been identified and investigated [6,7,8]
We have reported SID and CER of hydrocarbon cations and NH3+ with a variety of materials including stainless steel and fusion relevant materials like tungsten and others [15,16,17,18,19]
Summary
Study of reactive collisions of ions with surfaces is the area accelerated in last few years towards characterizing gaseous molecular ions and nature of the surfaces. A transfer of translational kinetic energy of projectiles into internal modes of energy has been observed during surface collisions of polyatomic ions, causing their dissociation. This energy transfer may help in characterizing the structures of projectile ions as well nature of surfaces [13, 14]. An urgent demand for data on collisions of low-energy (0100 eV) small hydrocarbon ions C1-C3 group, with We have simulated ion beam trajectories using SIMION 8.0, and found that about 10 % of the ion current may reach the surface to strike
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Mehran University Research Journal of Engineering and Technology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
