70 research outputs found
Study of photo-proton reactions driven by bremsstrahlung radiation of high-intensity laser generated electrons
Photo-nuclear reactions were investigated using a high power table-top laser. The laser system at the University of Jena ( I similar to 3-5 x 10(19) W cm(-2)) produced hard bremsstrahlung photons ( kT similar to 2(9 MeV) via a laser-gas interaction which served to induce ( gamma, p) and ( gamma, n) reactions in Mg, Ti, Zn and Mo isotopes. Several ( gamma, p) decay channels were identified using nuclear activation analysis to determine their integral reaction yields
RSD2013_v3/SiMTra_v2.2 - Simulation files of the examples in 'Modeling reactive magnetron sputtering: Opportunities and challenges'
A set of input files for the simulation software RSD2013 v3 and SiMTra v2.2 which generate the data used for the figures in the paper 'Modeling reactive magnetron sputtering: opportunities and challenges', published in Thin Solid Films (Elsevier) DOI:10.1016/j.tsf.2019.05.045. Also the set of experimental data for the current-voltage-pressure curves are included.
Four examples are illustrated by simulation:
1) Redeposition of sputtered atoms
- (SiMTra) Figure 1: Influence of working (Ar) pressure and the sputtered element (Li, Al, Ti, Y, Ta) on the fraction of sputtered material redeposited on the target.
- (RSD/SiMTra) Figure 2a: Hysteresis behaviour of reactive pressure afo reactive flow, varying the redeposition fraction of the sputtered material Al.
- (RSD/SiMTra) Figure 2b: Comparison of the critical points behaviour afo the redeposition fraction with a reduction of the sputter yield.
2) IV-characteristics
- (RSD/SiMTra) Figure 3a: IV-characteristic of a simplified Ti/O2 system (only one oxidation state).
- (RSD/SiMTra) Figure 3a: IV-characteristic of an Al/O2 system.
- (Experimental) Figure 4: Experimental IVP-characteristics fo an Al/O2 system.
3) Sample rotation
- (RSD/SiMTra) Figure 6a: Behaviour of the critical points afo the rotation speed of a substrate plate.
- (RSD/SiMTra) Figure 6b: Time evolution of the reactive gas pressure for two rotation speeds of the substrate plate.
4) Pulsing discharge current
- (RSD/SiMTra) Figure 7a: Behaviour of the critical points afo the pulsing frequency of the current.
- (RSD/SiMTra) Figure 7b: Time evolution of the target state by pulsing the current
RSD2013_v3/SiMTra_v2.2 - Simulation files of the examples in 'Modeling reactive magnetron sputtering: Opportunities and challenges'
A set of input files for the simulation software RSD2013 v3 and SiMTra v2.2 which generate the data used for the figures in the paper 'Modeling reactive magnetron sputtering: opportunities and challenges', published in Thin Solid Films (Elsevier) DOI:10.1016/j.tsf.2019.05.045. Also the set of experimental data for the current-voltage-pressure curves are included.
Four examples are illustrated by simulation:
1) Redeposition of sputtered atoms
- (SiMTra) Figure 1: Influence of working (Ar) pressure and the sputtered element (Li, Al, Ti, Y, Ta) on the fraction of sputtered material redeposited on the target.
- (RSD/SiMTra) Figure 2a: Hysteresis behaviour of reactive pressure afo reactive flow, varying the redeposition fraction of the sputtered material Al.
- (RSD/SiMTra) Figure 2b: Comparison of the critical points behaviour afo the redeposition fraction with a reduction of the sputter yield.
2) IV-characteristics
- (RSD/SiMTra) Figure 3a: IV-characteristic of a simplified Ti/O2 system (only one oxidation state).
- (RSD/SiMTra) Figure 3a: IV-characteristic of an Al/O2 system.
- (Experimental) Figure 4: Experimental IVP-characteristics fo an Al/O2 system.
3) Sample rotation
- (RSD/SiMTra) Figure 6a: Behaviour of the critical points afo the rotation speed of a substrate plate.
- (RSD/SiMTra) Figure 6b: Time evolution of the reactive gas pressure for two rotation speeds of the substrate plate.
4) Pulsing discharge current
- (RSD/SiMTra) Figure 7a: Behaviour of the critical points afo the pulsing frequency of the current.
- (RSD/SiMTra) Figure 7b: Time evolution of the target state by pulsing the current
Internal standardization in charged-particle activation analysis
An internal standardization method applicable to charged particle activation analysis of materials with unknown or variable matrix composition is reported. In a theoretical study the introduction of systematic errors by the use of the internal standardization method is evaluated. Approximations not requiring the knowledge of the reaction cross section are presented. The practical usefulness of the method developed has been checked by instrumental analysis of a few environmental reference materials
Feasibility Study on the Characterization of Thin Layers by Charged-Particle Activation Analysis
Deuteron activation analysis for the determination of carbon in iron and copper oxide, reagents for C-14-dating by accelerator mass spectrometry
Perspective: Is there a hysteresis during reactive High Power Impulse Magnetron Sputtering (R-HiPIMS)?
This paper discusses a few mechanisms that can assist to answer the title question. The initial approach is to use an established model for DC magnetron sputter deposition, i.e., RSD2013. Based on this model, the impact on the hysteresis behaviour of some typical HiPIMS conditions is investigated. From this first study, it becomes clear that the probability to observe hysteresis is much lower as compared to DC magnetron sputtering. The high current pulses cannot explain the hysteresis reduction. Total pressure and material choice make the abrupt changes less pronounced, but the implantation of ionized metal atoms that return to the target seems to be the major cause. To further substantiate these results, the analytical reactive sputtering model is coupled with a published global plasma model. The effect of metal ion implantation is confirmed. Another suggested mechanism, i.e., gas rarefaction, can be ruled out to explain the hysteresis reduction. But perhaps the major conclusion is that at present, there are too little experimental data available to make fully sound conclusions
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