Hi Sepideh

It could be done by a vacuum vapor deposition.

Hi Khaled

May I do Ti and Sio2 by this method too?

 I am looking for the best method and also one method that I can have the best thin films of Ti, Sio2 and Cr/Au.

could you please that I know your idea or anyone? 

Thank you

Hi

There are two factors which govern a thin film-coating method of the vacuum vapor deposition of  a metal or alloy  on a solid substrate.   The factors are the following:

1-The molten temperature of the metal or alloy; the lower the molten temperature of the metal or alloy the lower the vapor pressure of the molten of the metal or alloy.

2-The vapor pressure of the  molten of the  metal or  alloy;  the lower the vapor pressure of the  molten of the  metal or  alloy, the easier to evaporate the molten of the metal or alloy on the solid substrate in a vacuum chamber, at a pressure much lower than the atmospheric pressure.

Hi

I do agree with Mr.Marcello Conte.  

In general, the challenge of vapor deposition methods of a thin film of a metal/alloy on a substrate is how easy that one could obtain a molten metal/alloy phase with respect to the molten temperature of the metal/alloy.   In addition to what Mr.Conte has mentioned as far as the substrate thermal and electrical characteristics.     

Hi

I also agree with previous comments. 

I suggest you to use Magnetron Sputtering technique without any heating device to deposit high purity metal coatings (from 50 nm thickness up to a few microns) in a relatively quick and cheap way. There are quite a lot of coating service and laboratories equipped to do this job.

More complex the deposition of SiO2 coatings. If you need relatively high purity coatings and you need to avoid high temperature once more I suggest you RF-magnetron sputtering. If your substrate can support thermal treatment you can approach also chemical vapor technique such as CVD or MOCVD. 

If you can accept some Carbon and Hydrogen contamination you can deposit coatings by PECVD at room temperature in a very fast and cheap way.

Good luck !

Hi Sepideh

I also agree with previous comments.

The co-deposition CVD by using compounds with low-boiling and identic temperatures (as chromium hexacarbonyl and gold haloalkyls) can be used.

We did it with either e-beam evaporation or sputtering. Because Au is very expensive, you should be careful in choosing deposition methods. CVD is not the option for Cr/Au. 

E beam evaporation is the best suited option.

Hi Sepideh, one important thing to consider is that the incident metal from sputter deposition and electron beam deposition will be at a high energy, as a result they damage samples and in some cases induce electrically active defects. Thermal vapor deposition does not have this problem.

The plasma from sputter deposition systems is also bad for some samples as it has an etching effect.

Thank you so much of you all for your kindly consideration.