Non-contact mode profilometer (laser based) or ellipsometer (which works on interferometry as suggested by Alex) can be the solution.

Dear Colleague,

first of all, how thick are the thin films? In any case, please be careful with al mechanical devices. Most of them are using a needle and the narrow tip will scratch the surface... the results are mostly telephone numbers. The best way is via interferometry. Consult e.g. in the Internet ZYGO, or any other optical interferometric method... and you have to cover with a thin Gold layer if the polymers are not opaque

Regards alex

Non-contact mode profilometer (laser based) or ellipsometer (which works on interferometry as suggested by Alex) can be the solution.

Dear Colleague,

Hopefully you will find this helpful.

Best of luck.

The .pdf-attachment provided of Abdullah is a very nice intoduction into the thickness measurement theme. Good luck.

For a more detailed answer please tell a little bit more about the film, as Alex suggested.  Expected film thickness,  material of substrate and even adhasive layer(system) if applicable.

Dear Gerhard Martens,

Thanks for your answer. The thickness of the films are less than 150 nm and their substrates are kind of Transparent Conducting Oxide (TCO) electrodes.

Oh this is quite thin. If you do not insist upon a non-destructive method you could cut the electrode and perhaps take  a SEM microscope looking 'edge on' to the film. But 150nm is a challenge.

Hello, I would like to request you to follow the techniques suggested by Alex von Bohlen and Dhananjay Bodas. These ideas are more effective I think.

Dear  Ghamari,

If you have a smooth uniform film, then can use profilometer or AFM to find the thickness. But if the roughness of the film is very high then you may not get accurate values with these techniques.

Ellipsometry is best I think if you can measure in wavelengths where the film is (almost) completely transparent and the roughness is small compared to the thickness of the film. Cross section SEM will also be very usefull (150 nm can easilly be measured with a good SEM) so that you can also see the morphology.

But you are talking about 'available data'. Do you mean the current density data from the electrodeposition? That should also be able to give you the film thickness provided that you have a known faradaic efficiency for the formation reaction of your material, and that the procedure forms a dense film.