Dear All,
I want to deposit TiN and TaN by Ti and Ta targets (magneto sputtering). I tried to fabricate it with different conditions of N2 gas during the sputtering and post annealing beside N2. But I did not get a good result. If any one could share his or her experience about this, I would appreciate it.
All the best,
Parsa
Its fairly esy to sputter TiN coatings by sputtering techniques (rf/dc magnetron).
You must have a good base vacuum to begin with (10-6 to 10-7 Torr).
Your Titanium target surface should be absolutely clean. Pre sputter it for a long time in pure argon to remove all the oxide layer. Use high purity argon.
Later use high purity Nitrogen as a sputtering gas.
Try to optimise at different pressures, and different N2 gas flow.
You should obtain TiN thin films of different colors, and a good quality TiN will shine like gold like film.
Please get hold of this paper, they have some useful information. The literature is full of many good papers.
P. Roquiny et al. / Surface and Coatings Technology 116–119 (1999) 278–283
Oxygen contamination should be avoided. (from target surface, and the bleeding sputtering gas which is nitrogen). Use liquid nitrogen trap this helps.
K. Sreenivas
In a sputtering coater having Ti target, you have to introduce an optimized ratio of Ar and N2 gases in order to deposit a stoichiometric TiN film. Ignite plasma with these two gases to sputter Ti target. N2 gas atoms react with deposited Ti atom and form TiN film. Non-optimized ratio of the gases leads either Ti or N2 rich film. As prof. Sreenivas mentioned, stoichiometric TiN film has golden color. So you can understand if you observe the film visually. However to know film stoichiometry you need to analyze the surface to get atomic composition.
Similarly you can deposit TaN.
Agree with all the comments above. You should also be aware of the oxygen contamination in the annealing environment. Any oxygen could oxidise stoichiometric TiN film when annealed above 500 C. Forming gas annealing is recommended or vacuum annealing if it is acceptable for the process. Added below is a recent publication.
Article Effect of deposition conditions and post deposition anneal o...
Just want to point out that you need high-purity N2 (99.999%) rather than the low-purity N2 that is more routinely available. The N2 needs to have as low O2 contamination as your Ar. An LN trap won't clean O2 from your your N2 (though it will do great for H2O and CO2.
FWIW I've found that and Ar:N2 ratio of about 5:1 works well. That's just a starting point, but the optimum for your system should be around there.
Dear Parsa, Fully agree with Robert Bruce: use both Ar and N2 gas with 5N purity. In addition, if you have a large cathode and want to do long runs (e.g. dynamic coating on many substrates), you will need to work somewhere in the intermediate mode and stabilize your process with either voltage control or with a plasma emission monitor.
There are various kinds of in-line gas purifiers available in the market. Some of these are disposable, and should work well.
Alternately you can use Nitrogen generators used for Mass spectrometers, which really generate high purity nitrogen.
You can also look at one produce "Inert gas purifier" sold by R. D. Mathis and company, USA. They claim that their purifier can be hooked onto normal gas cylinders, and it further purifies it before introducing into the chamber.
Probably this purifier will work for both Argon and nitrogen.
I am myself trying to use it to obtain high purity nitrogen and argon gas.
K. Sreenivas
Substrate too matters. Pre-cleaning the substrate by chemical pre-treatment and also ion cleaning will provide good adhesion.
According to many respondents, first of all it is necessary vacuum within the chamber and then we will make a cleaning ionido argon bombardment of the surface of white and substrates.
is also important to optimize the gas N2 / Ar and sweep of the powers used for each target, it is likely that teams with different geometry and tank design conditions change.
I recommend you start with a 1:10 ratio N2: Ar is one of the most used, plus you do a sweep of the powers and make the respective characterization tests, when you have this you can write me and I will continue to help. Regards.
Thanks a lot everyOne. The Best sweep for making TaN was 2:5 N2:Ar and needed to annealing at 600'C for one hour beside N2.
- Badges
- Science topic
- Similar topics
- Engineering
- Materials Engineering
- Annealing