I have TiN, NbN, and AlN thin film samples, all of which are grown via MBE on silicon substrates, have a 5-10% oxygen contamination, and are about 50nm thick. Is RBS sufficient to determine the Nitrogen and Oxygen composition? Or should I use something like NRA to complement the RBS?
Hi Raphi,
RBS is enough to estimate the N and O concentration and also its always better to do with complimentary techniques as well for comparison.
Hello,
Thank you so much for helping me with this issue. But I forgot to mention that my supervisor has asked me to determine the compositions of the N and O without making the assumption that there are no other contaminants. I.e. I can't simply subtract the percentage of titanium from 1 and assume the rest is Nitrogen and Oxygen. Additionally the energy level range of the Silicon substrate overlaps with that of Nitrogen and Oxygen. Would either of these make another measurement technique necessary?
but XPS can only measure elementar concentration on the surface that is exposed with x rays,
RBS is better for owerall, but I agree that combination is the best
Dear Raphi,
As the thickness of nitride thin film in your specimen is ~ 50 nm, and its 5 - 10 % is of Nitrogen and Oxygen, so from the RBS spectrum, you will be able to identify their presence.
But because of such small amount, determination of exact compound (with nitrogen or oxygen) is very difficult. In this case intensity of the backscattered signal from target Nirtrogen and Oxygen will be very small.
With best regards,
Anjan
@ Stefan You’re absolutely correct, but at 50 nm, then this is practically all surface and I’d expect to see a high proportion of C on the surface.
@ Alan, can I assume the nitrogen content with in the detection range of XPS is representative of the whole thin film? I just received an estimate from the person doing the measurements and the error for the nitrogen peak will is 30%. Also thank you fr being so helpful.
as I understood, when apply RBS you should do calibration, as done by P. Prieto et al.
https://doi.org/10.1002/sia.2658
Thank you to all with your helpful responses, I am waiting for my RBS data to come back and will see how good it actually is.
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nanostructures
- Thin Films