We can categorise the methods in two groups: direct and indirect. Cross Sectional SEM, Cross sectional TEM, Profilometry (both Stylus type and Optical), AFM etc. can be grouped as direct. On the other hand, Optical methods such as Spectrophotometry, Ellipsometry & Interferometry, Conductivity measurement, Etching rate determination, Weighing method etc. can be called as indrect.

You can measure the thickness of your film by profilometer or XRR or cross sectional TEM

You can Measure the thickness first with cross sectional SEM and then confirm it with profilometer. If you are not satisfied with this then use the Reflectance VS Wavelength spectra using spectroscopic technique and then use envelope method (Material science-Poland,Vol. 25, No. 3,2007)

What is the thickness range ?

More ideas:

1.You could use etching rate in known etchant.

2. You could measure the conductivity or impedance vs frequency. -> http://rsi.aip.org/resource/1/rsinak/v63/i6/p3455_s1

Sajid Husain, Envelope method by Spectrophotometric technique is not applicable for very thin films ~ 50nm or less. If there is no interference fringe, this method can not be applied. You need appropriate thickness for having interference fringes in Transmittsnace or Reflectance spectra. Minimum thickness required for interference to happen, depends on the material since constructive interference (for Tmax or Rmin) and destructive interference condition (for Tmin or Rmax) depend on the product nd (n is the refractive index of the material and d is the thickness of the film). Higher the refractive index, less is the thickness required for interference to happen.

In this context, R. Bogdanowicz's question is very relevant.

using elipsometer.....

What do you mean "without any other instruments"? Are you hoping somehow to a priori determine it? A crude way is the measure the resistivity and Mathiessen's rule, if you know the thermal component of the resistivity. That at least avoids destructive techniques

For metallic film like Al, you can use Stylus Profilometer if you can create a sharp step by masking a part of the substrate during deposition..

However, it is important to know the thickness range you are talking about.

You can try profilometers. If both the film and the substrate are transparent you can try other optical techniques, as well, such as UV-Vis; using a simulation software and known values of refractive indices you can estimate the thickness that way.

To R. Bogdanowicz thickness range is 200-300nm

To Phillip Broussard without instrument means by any analytical way of calculating the thickness of 200-300nm

for thickness less that 50nm, its better try with profilometer. If u can slice the specimen perfectly without any residual stresses, u can go for high magnification TEM

Guru Prasad, by only analytical way is not possible! There is need to have some data obtained experimentally. For example, transmittance or reflectance data by Optical Spectrophotometer. You can use those data in an analytical method to derive thickness. You can even get the weight difference by 6th place Microbalance and calculate the thickness, if you assume the density to be identical with the bulk material. However, in both the cases, you need some sort of Instrument to experimentally get the data related to some physical property.

Are there any other electrical methods than described in this discussion I-V /C-V?

Perhaps making a calibration curve of a similar materials with known layer thickness and using say UV in transmittance mode could work

200-300 nm of Al is to much for ellipsometry (light absorption). I would try etching method. Check graph on 2nd page http://www.microchemicals.eu/technical_information/aluminium_etching.pdf

We can categorise the methods in two groups: direct and indirect. Cross Sectional SEM, Cross sectional TEM, Profilometry (both Stylus type and Optical), AFM etc. can be grouped as direct. On the other hand, Optical methods such as Spectrophotometry, Ellipsometry & Interferometry, Conductivity measurement, Etching rate determination, Weighing method etc. can be called as indrect.

optical transmission measurements in UV-VIS-NIR can be used for thin films deposited on transparent substrates (corning glass) in order to determine thickness, refractive index, optical gap

Ellipsometer is a very good and easy option to measure the film thickness without harming your deposited film.

a change of phase(due for example thickness) will generate interferograms when is combined with the original beam of a laser. Exist documentation, I have not at hand. Of course is not for any range of thickness.

I just google it. http://maxwell.uncc.edu/adavies/Amit_dissertation.pdf

Also for thick films and big substrates, you can weight before and after your substrates, if you have a uniform deposition and you know the density you can calculate what is the volume of your film, then your thickness.

If it is the control of the thickness of the thin film quartz crystal microbalance can be used.

Yes, Dr, Siva Kumar. Quartz Crystal Microbalance is very useful in estimating roughly the film thickness during deposition. It is an in-situ method. But it is not a precise method to determine film thickness.

I wanted to add that in case of depositedaluminum layer the most appropriate method is ellipsometry

I'm surprised about your curious question. How do you count to measure analytically the thickness of your films, if you ONLY know the refractive index of material, and you do not want to use any experimental technique? Do you know how many atomic layers have you deposited? Have you deposited a crystalline (not polycrystalline or amorphous) film? Do you know the crystalline allotropic phase of your film? As you can see, if you count to use ONLY analytical techniques (without the use of any experimental technique) you're confronted to a lot of open questions that's difficult to solve. Work on REAL world are outside the analytical world, and experimental studies are necessary in order to know THE REAL THING. If you're already involved on the process of preparation of the aluminum films (an experimental task), then you wouldn't be afraid of the experimental characterizations, right? May the force be with you!

You cannot use an ellipsometer to measure an opaque metal film.

if the film is fairly thin, less than a few microns, deposit over a small piece of Kapton tape, peel off the tape after dep, and then measure step with profilometer.

If the film is thicker than that use a shadow mask like a small piece of Si wafer, again use profilometer.

You can also use RBS technique to determine the thickness of the film.

It depends on the thickness of the film. If it is sufficiently thin and have some transparency you can deposit it on glass substrate, measure transmitance T and reflectance from front and back side of the film. In this case you will have three knowns (T, Rf and Rb) for determination of the three unknowns - refractive index (n), extinction coefficient (k) and thickness (d). If the film is thick than use profiler. Of course you can use profiler in the first case as well

To Tsvetanka Babeva, it will be knowledge-adding to us if you please elaborate how you use T, Rf and Rb in evaluating three constants. What are the relevant equations to be used for this purpose? Can you please cite a reference also for this method? Thanks in advance!

If you have to measure the thickness of Aluminum thin film deposited on light substrates (for example carbon), you can use RBS measurementson of Aluminum

Sorry:

If you have to measure the thickness of Aluminum thin film deposited on light substrates (for example carbon), you can use RBS measurements

for measurements of the thickness of thin films, we can use profilo-meter by making a stack on the substrate . in addition , cross sectional SEM and TEM is also useful for the thickness measurement.

To Suchitra Sen

You can find the algebraic method for finding n, ka nd d from T, Rf and Rb in V. Panayotov and I. Konstantinov, “Algebraic determination of

thin-film optical constants from photometric ~T, Rf, Rm! and ~T,

Rb, Rm! measurements,” in Optical Interference Coatings, F.

Abeles, ed., Proc. SPIE 2253, 1070–1079 ~1994!

Another approach is to use minimization algorithms for minimizing the discrepancies between measured and calculated values of T, Rf and Rb. Please see the attached paper.

Thanks, Tsvetanka.

Digital Micrometer also used to find the film thickness. But its not give accurate value, its give only approximate value of the film in micrometer range.

Please; Can someone tell me what is the main equation of the transmission and thickness that the Ellipsometry used for the calculations? I used the DeltaPsi software and HORIBA YVON Device?

Can some one tell me how can I calculate n and R of any thin film using (UV-VIS) Spectrophotometer?

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Use UV vis

One can use quartz crystal thickness monitor.

QCM can be used during deposition,