Dear All
In making a quasicrystal, I used the Si substrate. However, I have Si diffusion on my samples, so I used Al2o3 and got five fold symmetry. But in most of the papers, they used different substrates for thin film deposition(sputtering). May I ask you, did you have any quasicrystals grown in thin film on SiO2 substrate? If it is not possible, what kind of composition or metal is possible for being a substrate during quasicrystal production?
Sincerely,
Parsa
Dear Amirkabir, your question cannot be answered without knowing your deposition technique, the deposition temperature, and the composition that you target. Anyway, if you process your films at high temperature there is little chance for you to be able to control interdiffusion. Unless, if you have a stable oxide at the interface.
Dear parsa, Sputtering is not usually used for quasicrystal. If you may use the machine, I think, you must grow a quasicrystal at high temperature. AlN crystal grown by high temperature sputter has quite good crystallinity. And if you may use a SiO2 substrate, you should consider the crystal dircetion between the film and the substrate. It is very important.
Dear Hae-kon Oh
thanks for your reply, can you clarify what you mean by considering the crystal direction between film and substrate? My composition is AlCuFe and temperature is around 700 'C.
Best,
parsa
Dear Thomas Duguet
I used sputtering thin film and my composition is AlCuFe. the temperature is around 700 'c. for control the surface oxidation I deposited thin layer of Al on top. the problem in my case is, can I use the Sio2 as a substrate and growing crystal on it ? or I need to use the inner layer between the substrate and my composition(AlCuFe).
All the best
Dear paraa
Sorry, but I think that the relationship between film and substrate shall be needed various experiment. And the method without Si diffusion may be the using of 3C-SiC interlayer, I think.
OK, most important in the case of Al-Cu-Fe QC is to control the chemical composition of the film. Actually, the stability domain of the QC phase is very reduced. Therefore, make sure that you use an oxide (whatever oxide, SiO2 can be OK) which is stable at 700°C (Cu-Si afinity is quite high, for instance). Anyway, even if you perform the deposition o the QC phase on top of the oxide (which is already difficult to achieve), you will have problems with the film peeling off from the subtrate. A very interesting startegy that I never tried would be to make an under stoichiometric film, and use the interface diffusion to end up with the proper QC composition (e.g. lower content of Fe on an Fe substrate). With that method, one could form a strong interface... But this may take a while. Good luck!
- Badges
- Science method
- Similar topics
- Methodology
- Crystallography
- X-ray Diffraction