Hello sir, I have fabricated 193-Iridium on Aluminum backing. I am using SIMNRA software for the simulations, but the simulated line is not falling on experimental data points. Could you please help me with it? Thanks and Regards
Very nice video, I found the explanations clear. Question: do you know if the metallization process (used to deposit Au on the MgO) would typically result in gold implantation into the MgO substrate? (Is the deposition process very energetic?) Or might this Au implantation/diffusion have happend during the RBS measurement? I don't have much background in this type of measurement, so apologies if this is a bit of a beginer question.
Good question. RBS is a scattering problem and as such is influenced by the masses of the interacting particles. The scattering ions (helium, hydrogen, etc.) ricochet in a manner determined only by momentum transfer from elastic scattering with the nuclei. Chemical bonds can only react to the motion of the atom after the nucleus scattering event has occurred. So the scattering ion is not influenced by the recoil, and thus not influenced by the chemical bonds.
I think you are asking if there is a file that I needed to prepare before running SIMNRA. You do need to read the spectrum as an input file. I convert the spectrum to an ASCII file before selecting "read spectrum". It will also read the .cam files generated by Canberra software, but I have never done that.
Alpha particles don't go very far in a gas. After about 2 cm in air, the beam would be attenuated to almost nothing. UHV is needed so that the alphas can survive the trip down the beamline, into the chamber, and finally to the detector. An interesting application of the short travel of alphas in media is the smoke detector. The alphas can cross a narrow gap in air, where they are absorbed at an electrode. But when that gap fills with smoke particulates, the alphas are absorbed instead by the particulates.
With the energy of alpha particles that I have been using, RBS can detect heavier nuclei a significant fraction of one micron beneath the surface. But the depth of sensitivity is quite limited, so I would agree that it is a surface technique, but with thin film depth profiling capability.
@@stephenremillard1 so finally RBS is a surface analysis technique but a leader because of what ? for example in XPS and AES because of the average free path but in RBS why ? and thank you thank you perefessor
@@mohibmohib6442 I think nondestructive depth profiling, especially of films, is the key strength that attracts me to use RBS. My understanding is that Auger produces depth profiles by removing material, one layer at a time.
Typo at 17:40. The exponent on the 3rd line should be "8" instead of "6". ==> (1.08x10^8)t
Hello sir,
I have fabricated 193-Iridium on Aluminum backing. I am using SIMNRA software for the simulations, but the simulated line is not falling on experimental data points. Could you please help me with it? Thanks and Regards
please could you tell me how you calculate the thickness for the layer 2 which is composed of O, Mg and Au.?
See the discussion at 17:34. Because the gold concentration is very low in the diffusion layer, I used the density of MgO for that layer.
Very nice video, I found the explanations clear.
Question: do you know if the metallization process (used to deposit Au on the MgO) would typically result in gold implantation into the MgO substrate? (Is the deposition process very energetic?) Or might this Au implantation/diffusion have happend during the RBS measurement?
I don't have much background in this type of measurement, so apologies if this is a bit of a beginer question.
Hello please please proffessor
RBS does not give information about chemical bonding why ?
Good question. RBS is a scattering problem and as such is influenced by the masses of the interacting particles. The scattering ions (helium, hydrogen, etc.) ricochet in a manner determined only by momentum transfer from elastic scattering with the nuclei. Chemical bonds can only react to the motion of the atom after the nucleus scattering event has occurred. So the scattering ion is not influenced by the recoil, and thus not influenced by the chemical bonds.
Hey Sir, did you attached the file of the SRIM Software on SIMNRA before start the analyses? or can i do the fit without this?
I think you are asking if there is a file that I needed to prepare before running SIMNRA. You do need to read the spectrum as an input file. I convert the spectrum to an ASCII file before selecting "read spectrum". It will also read the .cam files generated by Canberra software, but I have never done that.
Why RBS does he need to ultra-high vacuum ?
Alpha particles don't go very far in a gas. After about 2 cm in air, the beam would be attenuated to almost nothing. UHV is needed so that the alphas can survive the trip down the beamline, into the chamber, and finally to the detector. An interesting application of the short travel of alphas in media is the smoke detector. The alphas can cross a narrow gap in air, where they are absorbed at an electrode. But when that gap fills with smoke particulates, the alphas are absorbed instead by the particulates.
Hi proffessor
can we say RBS is a surface analysis technique? and why ?
With the energy of alpha particles that I have been using, RBS can detect heavier nuclei a significant fraction of one micron beneath the surface. But the depth of sensitivity is quite limited, so I would agree that it is a surface technique, but with thin film depth profiling capability.
@@stephenremillard1
so finally RBS is a surface analysis technique but a leader because of what ? for example in XPS and AES because of the average free path but in RBS why ?
and thank you thank you perefessor
@@mohibmohib6442 I think nondestructive depth profiling, especially of films, is the key strength that attracts me to use RBS. My understanding is that Auger produces depth profiles by removing material, one layer at a time.