Discovering thickness of a thin film.

[darker4308]

Hi guys, long time reader new poster.

I am looking for ways to determine the thickness of some thin films of zinc oxide I have been producing. Conventionally I use SEM cross section, but the throughput of films has made this a little taxing. I've tried also weighing the substrates before and after coating and that seems a little imprecise. We do not have a film growth monitor.

Does anyone have any other idea for measuring film thickness.

 

[ZapperZ]

It depends on the thickness.

If it is very thin and semi-transparent (at least to visible light), then you can you ellipsometry.

Zz.

 

[darker4308]

We tried that, but the variance in the films is so high that we can't decide what harmonic is correct for the thickness value without doing an SEM which defeats the purpose.

 

[chrisbaird]

We use x-ray diffraction to measure the thickness of layers on the nano-scale. I'm not sure if that would be appropriate in your case.

 

[darker4308]

I am curious I've taken material science at a graduate level, but we all we ever used XRD for was identification and grain size. Is there a fundamental formula that you can point me towards so I can measure film thickness, and also what do this depend on ?

My films range from about 10nm to 400 nm or so, and we would really like a method to be able to get close to 10nm resolution.