We are working about influence of optical, electrical and structural properties of AlN thin film under various deposition conditions. We deposited AlN on the quartz substrate under 100,300,400 degree and flow percent of nitrogen (2%,5%,10%,20%) and with 120 nm thickness by DC magnetron sputtering. The XRD result in all of samples was Amorphous. Is it possible that the XRD setting is faulty or do other faults exist in my experiments?
I don't have any experience on AlN films but you can easly verify if your XRD apparatus is working correctly. Just put your quartz substrate without film on your XRD apparatus. As far as I remember quartz has a cristal structure. Then you have to observe some diffraction patterns. If you are not sure about your substrate, you can do an XRD experiment on a copper or a steel sample that you can easly find around you, in order to check your apparatus.
How can you be sure that you deposited a film on your substrate? Do you have other technique to check if you deposited someting (amorphous or cristal)?
It is also possible that your fims (!) are very thin for your XRD apparatus in your conditions.
Though having no experience on the AlN but i am working in the Amorphous Oxide semiconductors. you said that you deposited the films at the temperature upto 400 0C on the quartz substrate. You can check XRD machine as Attila suggested. But for the amorphous films my suggestion is follows.
There are two methods for making crystalline films first use any crystalline plate as substrate and then deposit the material at some substrate temperature. And the other one is you deposit the film at room temperature or some low temperature (for better nucleation) and then anneal it to its crystallization temperature.
Hopefully your XRD system is fine as you are using the Quartz substrate for the deposition which itself is amorphous by nature. I have checked with literature that crystallization temperature of AlN is greater than 750 0C. If you can take the substrate temperature upto this high then its Ok otherwise you can anneal your film at Temperatures higher than 750 0C.
Hope this will solve your problem.
I though that the AlN with120nm thickness is extremely thin. Why not to try to use a Grazing Incident Diffraction(GID) method. Maybe is hopeful for you to identify the AlN which is amorphous or crystal. By the way, one method suggestion for you.The preparation of the AlN thin film by depositing on copper sheet and then a carbon thin with 30nm cover on AlN in order to grip it. Finally, the Cu sheet is etched by acid solution and then the thin (C/AlN) film is captured by a copper grid. TEM analysis is very powerful to identify optical, electrical and structural properties of AlN thin film.
HI
FYI we developed AlN photodetectors for UV solar observations. One of our best AlN samples so far comes from DOWA company (Japan). The AlN thickness is 1 micron and it is deposited directly on sapphire substrate (not quartz).
also have a look on this paper:
https://www.researchgate.net/publication/231055140_Design_fabrication_and_physical_analysis_of_TiNAlN_deep_UV_photodiodes?ev=prf_pub
"… . AlN films are deposited on the sapphire (Al2O3) substrate by MOVPE. The growth temperature is 1100 ◦C under 100 Torr growth pressure".
If you need more information, let me know i can directly ask to my colleagues who did the deposition.
Article Design, fabrication and physical analysis of TiN/AlN deep UV...
because your adatom (addatom) mobility is too low..
reduce pressure (to have more energy to your sputtered/reflected particles), increase the temperature even more, increase your plasma density (iPVD, Hipims or so)
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