For people who can’t afford the software or have difficulty with the spreadsheet that was given I would recommend the papers by Swanepoel (which I think was briefly mentioned in an earlier post) The citations are listed below. The formulas can easily be used and put into a computer. They also allow you to vary your parameters and easily plot them on top of your experimental data. This is very useful to do at least once since it can give you a good intuition as to how your data changes with respect to varying a parameter in an intuitive way. Even more importantly, it can help understand the importance of scattering or surface roughness on your data and give you an idea of how much that impacts your measurement. Finally, you have to remember that the index and absorption is a function of wavelength and the Swanepoel formulas let you input dependencies in a natural way.

The other thing that is missing from the discussion is that depending on the nature of the material, that for measurements around the bandgap, one really should have some idea of the fundamental properties of the material. i.e. in GaN or ZnO the exciton can have a significant impact. For alloys of those materials alloy broadening can alter the spectra. Thus the dispersion can be changing rapidly.

For routine measurements where you know what you are depositing, the Swanepoel method should work pretty well.

Title: DETERMINATION OF THE THICKNESS AND OPTICAL-CONSTANTS OF AMORPHOUS-SILICON

Author(s): SWANEPOEL, R

Source: JOURNAL OF PHYSICS E-SCIENTIFIC INSTRUMENTS Volume: 16 Issue: 12 Pages: 1214-1222 DOI: 10.1088/0022-3735/16/12/023 Published: 1983

Times Cited: 1,850 (from Web of Science)

Title: DETERMINATION OF SURFACE-ROUGHNESS AND OPTICAL-CONSTANTS OF INHOMOGENEOUS AMORPHOUS-SILICON FILMS

Author(s): SWANEPOEL, R

Source: JOURNAL OF PHYSICS E-SCIENTIFIC INSTRUMENTS Volume: 17 Issue: 10 Pages: 896-903 DOI: 10.1088/0022-3735/17/10/023 Published: 1984

Times Cited: 372 (from Web of Science)

There is this software made here in Brazil.

http://www.ime.usp.br/~egbirgin/puma/

Thank you ahmed Naji I will contact you.

Tank you Giacomo bosco, I will install PUMA sofware and hopfuly i will get used to it.

Best regards

Hi

to calculate the optical constants , it doesn't need a soft ware you can build your own program , you should know which relations or equations you have to use .

employ a microsoft excel worksheet and the film thickness for which transmetance or reflection spectral data then you can calculate the optical properties of the films

Thank you

please, PUMA software can works with windows XP?

Best regards

Yes, you really don't need a software to obtain these parameters. You can use the Swanepoel method to do exactly what you said: use a worksheet e write down all the equations and get the constants and thickness. But once you get used to the software the analysis become much faster and easier to employ, I think.

Yes of course.

Hi Dr Ali -Jabri,

Yes some times it is easy ; but in my case I don't have the thickness, it can be verys thin say 50nm and absorbant, and no sign of interferences in reflectance or transmitance spectra,. Any way if you have a document that explains how you do it without a sophisticated software , please put a link to it in this page or e-mail it to me; here is my e-mail [email protected]

thank you very much

Working with Excel for swanepoel method is good.

I have model excel sheet if you need i'l send to you

You can develop your own program using well known R and T equations. You can refer my paper published in Vacuum Journal 31, number 141-145, 1981. But these equations are applicable for thin films deposited on an infinite substrate. You have to use connecting equations applicable for a parallel plate substrate. There are ways of determining the exact thin film thickness using an iterative scheme. These details are available in the above paper. try to develop a suitable program in C or Matlab or Fortran. You will be successful. If you have any difficulties contact me. nagendra

Is there any software for ellipsometry??

you can see parav-v2.0.exe free for unifome thikness. I suggest you develop your own program

To obtain an optical parameters fot thin films. You can use the excel and write down all the equations and get the constants as, realpart, imaginary part of dielectric constant and refrective index, so on .

Yes there is an execl file use to calculate all the optical parameters and draw all the curves. If u want i will send it to you

Kindly send the excel file to me

To Mohammed Razooqi

Please, send me the excel file to me

regards

I would like also to receive the excel file. Thanks in advance for your attention. Regards.

Dear Adel, Raj and Roseli i will send it to your e-mails as soon as possible

regards

Dear Mohammed, I would also be interested in your excel file. I you are kind enough to mail it to me I would appreciate it. regards my mail *********

I am witting to get the file

Thanks a lot Mohammed

Dear Mohammed Razooqi · University of Tikrit

Please send me this execl file to calculate all the optical parameters and draw all the curves at my email address ([email protected]). Thanks a lot in advance.

@Mohammed · University of Tikrit

dear Mohammed,

I would also like to receive the excel file.

My email is [email protected]

Thank you in advance. MK

RefFIT program, developed by Dr. Alexey Kuzmenko, fits optical spectra, such as reflectivity, transmission, ellipsometric PSi and Delta, etc. It runs on Windows platform. And it is free of charge.

http://optics.unige.ch/alexey/reffit.html

Kindly send me also on mail:

Dear Mohammed

please send me the excel files for optical parameters

Hello Mohammed and Sriram, could you please send me the excel files to my email:

Dear Mohamed razooki,

Yes please send me this excel file for optical constants , my e-mail is

please Dear Mohammed send me the excel files for optical parameters

Dear Sriram,

please send me the excel file for optical parameters

Dear Sriram and Razooki,

Kindly send me the excel kit, it will be of help.

Thank you in advance

Hi

By excel files it is easy to calculate the optical parameters.

Using the swanepoel method it is possible to calculate the thickness of film from the interference fringes of the transmittance spectra. Whether you will need the excel file and determination of the thickness and optical

constants article (R Swanepoel) i will attach those. I hope you will find information regarding the optical parameter calculation in Swanepoel paper and helps in the results interpretation .

I will give some information about the thickness of thin films. In general the thickness is not uniform through out the sample itself. The thickness in the middle part of the sample is somehow different to that of the edges.

One way to find the thickness is by Scanning Electron Microscope in cross-section view of samples using .

Dear Mohammed Razooqi

I am still waiting for the excel file to calculate the optical constant

my e-mail is

regards

thanks Mohammed, I downloaded.

Thank you very much Mohamed, I downloaded.

May God bless you excellent work M.Razooqi.

Thanks for the program

Thanks a lot Mohammed

Please send me you e mail on and i will send you a file to be checked

regards

Dear Dr. adel, Austin, you wellcome, this excel sheet is work made, and i am ready to help you in any thing about thin films, spacially CdTe, CdS and GaAS, as a thin films, solar cells, and junctions

regards

Dear Mohamed Razouoqui,

Tahk you very much for the excell file , I download it. It will help if the film thickness is known. However if the film thickness is not known and there are no interferences in the reflctance an transmitance spectra because the film is too thin; then how can I estimate the thickness, n and k? any body knows? Is ther any special equation to use?

Best regards

dear Azzeddin the faster way and to estimate the thickness of the films i advise you may using the weighting method but it is not very accurate, and you wellcome

Regards

Kindly send the optical constant calculation excell program to me:

Dear Bektar i attached the file in the top of this page and if you cannot get it my mail is send me a message and i will send it to you

Information provided by Davor Gracin

Ernesto G. Birgin, I. Chambouleyron, J.M. Martínez, Estimation of the opical costants and the thickness of thin films using unconstrained optimization, Journal of Computational Physics, 151, 862-880, (1999)

Andrade, R., et al., Estimation of the thickness and the optical parameters of several stacked thin films using optimization. Appl. Opt., 2008. 47(28): p. 5208-5220.

Thanks for providing the Excell program.. we r using it... Thanks again..

Dear Robin taylor thank you for your interest really i will check your notes and then contact you to discuss the subject, and i try to delet the file befor you ask because i want to save the copyright, but reallly i dont know. please tell me.

best regards

Mohammed

Dear robin this excel sheet is a trying to help the researchers, there is many researchers likes it and it work very good with thier data. You may have righ in something but i dont think you are right in everything i will repeat the thinking in the excel sheet and find if you r right and i will correct the error if in. The researchers in our country hold all the responsibilities, like calculations, prepared, depositing , manufacturing and measurments, not like yours, concentrate in one direction and other tasks are not in his mind

Dear all

I deleted the file of calculating the optical constants . but i promise you i will attached it again

Regards

Dear Dr Taylor;

In response to your list of flaws in the original program- although you are technically correct in all points, the complete rejection of the original gesture made by Razooqi was unnecessary unless you simply attempting to flex your intellectual ego. There are several constructive ways to correct inaccuracies. I appreciate the contribution from Mohammed and have made some corrections to it myself for another application. Either way, regardless of whether R, T, and absorbance are convertible to one another or not, the index of a film can be calculated if interference fringes show up on a spectra and the thickness is known. This will of course only provide the real portion of n, but it depends on what you need. Ellipsometry could work as you indicated, but has many limitations such as film thickness, surface roughness, and porosity. It does however also provide dispersion information (n vs lambda) which can't easily be taken from interference fringes.

Thanks again for the spreadsheet Mohammed.

Mike.

I agree totaly with every word said by Robin. Also Mohammed's efforts to help others should be applauded

however he should discuss his ideas with his supervisor or his ex-supervisoror any expert in optics of thin films before posting his files. I did not reply immediately because I was far away from home (I took a break of 2 weeks in a placenear the sea where there are no books and no computers). On the other hand the corrected excell file posted by Robin is OK only if the reflection is null which is not always true. When I started this subject I have in mind that the transmitance and the relectance spectra are known by measurement and not by calculation or any speculation also the relection of the substrate before being coated is measured ,( both of these reflections are needed to correct the measured alpha from loss by reflection). Refractive index of substrate (glass) is suposed to be known and real. Thickness, n and k of the coating are not known . My question is: Is there any free software for n,k and thickness determination when the film is too thin to show interferences?

I know that there are some comercial reflectometers that can measure thickness from Reflectance spectra in a matter of a few seconds ( this is what they say) but the price of the reflectometre and its software vary from 7000$ to 13000$. A standalone software of these reflectometers price is around 4000$. That's why I was looking for a free software that would do theses very complicated equations based on some Drude models or others. I am not an expert in computing but there must be somebody who is an expert in this field and want to help the thin films community and is ready to post his sofistigated programme free of charge.

Best regards

dear all also me was far away from home there for i can not reply as fast as possible but :

if the excel sheet that i uplouded has an errors, but this is not mean that the robin correction is true therefor i suggest to solve this problem we must tak the spetrum of R from the spectrometer directly.

regards

mohammed

Dear Micheal could you send me your mail my mail is [email protected]

Regards

Mohammed

Dear all,

I have to say that I was a little bit disappointed reading above some personal attacks among the member of the forum. Anyway, the purpose of such fora is the transfer scientific knowledge to colleagues needing it. Finally, I was glad to read that the limits of the application of this famous Excel sheet came to an agreement.

Now I have a further question:

I suppose everybody in the forum knows the book of Heavens with the title "Thin Solid Films". In this book, some general formulas are given for T and R that result from the matrix approach used in this book.

Some simplified formulas are presented then for special cases, such as T and R for a transparent (or not) film on an transparent (or not) substrate etc.

These formulas should be also valid for films with thickness less that 100 nm. In this case, no fringes are seen, so one has to fit the whole curve with d, n and k as parameters.

I suppose if d is deduced by another method, such as profilometry, the fitting should be simplified.

I would like to have some comments from the members of this forum on this approach.

Dear Michael

please tell how to fit the data using n,d and k.

I'm bit confused coz we are going to find n, d and k from either T or R.

So we need first T or R right.

Dear Sriram,

Yes, of course you need to record T or T first.

Then you set the constants for air and substrate and what remains to be fitted is d, n and k.

A useful approach for n could be the Sellmeier equations.

As stated above, to deduce d from an indepented measurement is a great help.

Dear Michael

Can you send the procedure to fit the data with some example.

Dear All,

Please I want the following article

D. Poelmen and P.F. Smet, J. Phys. D: Appl. Phys., 36 1850 (2003).

" Methods for the determination of the optical constants of thin films from single transmission measurements: a critical review"

Try RefFIT by Alexey Kuzmenko http://optics.unige.ch/alexey/reffit.html. It is quite robust for many applications.

Yes there is. I think you can make use of Scout Thin Film Analysis Software.

Dr Robin Klupp Taylor,

thank you. I found

For people who can’t afford the software or have difficulty with the spreadsheet that was given I would recommend the papers by Swanepoel (which I think was briefly mentioned in an earlier post) The citations are listed below. The formulas can easily be used and put into a computer. They also allow you to vary your parameters and easily plot them on top of your experimental data. This is very useful to do at least once since it can give you a good intuition as to how your data changes with respect to varying a parameter in an intuitive way. Even more importantly, it can help understand the importance of scattering or surface roughness on your data and give you an idea of how much that impacts your measurement. Finally, you have to remember that the index and absorption is a function of wavelength and the Swanepoel formulas let you input dependencies in a natural way.

The other thing that is missing from the discussion is that depending on the nature of the material, that for measurements around the bandgap, one really should have some idea of the fundamental properties of the material. i.e. in GaN or ZnO the exciton can have a significant impact. For alloys of those materials alloy broadening can alter the spectra. Thus the dispersion can be changing rapidly.

For routine measurements where you know what you are depositing, the Swanepoel method should work pretty well.

Title: DETERMINATION OF THE THICKNESS AND OPTICAL-CONSTANTS OF AMORPHOUS-SILICON

Author(s): SWANEPOEL, R

Source: JOURNAL OF PHYSICS E-SCIENTIFIC INSTRUMENTS Volume: 16 Issue: 12 Pages: 1214-1222 DOI: 10.1088/0022-3735/16/12/023 Published: 1983

Times Cited: 1,850 (from Web of Science)

Title: DETERMINATION OF SURFACE-ROUGHNESS AND OPTICAL-CONSTANTS OF INHOMOGENEOUS AMORPHOUS-SILICON FILMS

Author(s): SWANEPOEL, R

Source: JOURNAL OF PHYSICS E-SCIENTIFIC INSTRUMENTS Volume: 17 Issue: 10 Pages: 896-903 DOI: 10.1088/0022-3735/17/10/023 Published: 1984

Times Cited: 372 (from Web of Science)

Dear Azzeddine and Colleagues

I am a newcomer to the research gate discussions. I am amazed by the fruitful ideas it produces. I believe it is important to that we do not mistake the healthy criticism to ideas and procedures with personal attacts, as I have noticed in almost 100% of the answers posted.

To add some references do the excellent work of Swanepoel mentioned by J. Muth, and to the very serioulsly develop PUMA routines, I would suggest also the work by J.I. Cisneros, Optical characterization of dielectric and semiconductor thin films by use of transmission data" Applied Optics 37 (22), 5262-5270 (1998). There you can also find the expressions ready to use in the computation of optical constants.

Best regards.

Dear Silva,

Thank you for the in formation. However I don't have free access to papers which are more than 10 years old. Would you please send me a pdf file of J.I.Cisneros paper please.

Best regards

Yes free soft ware JPGM is there to find optical constants

Dear Azzeddine

I couldn't find your e-mail address. Please update your profile.

Best regards.

Dear J. Silva,

my e-mail is there in the contact , iinfo. Here it is [email protected]

Best regards

how to get that JPGM software i tried to search but unable to find

We have developed software based on the method of Swanepoel. We use it for almost a decade for the determination of physical and optical constants of hydrogenated amorphous silicon thin films and its alloys (a-SiGe: H, a-SiC: H, ...) deposited on corning glass substrates. The results are very convincing and have been the subject of several publications.

Thanks Kechouane. We are working on metal oxides so is there any option for these materials in your software and how I can get that software.

Kechouane, You developed the software. is it for free?

ntvdm.exe (When we search for the properties, we get thie file, But it is free downloaded software to find the optical constants of oxide materials, written by C++

This software was developed by a PhD student in our laboratory. It enables using a data table, according to the transmission versus wavelength, to determine the refractive static index, thickness, and the absorption coefficient and the gap of the material.

Dear Junaid Ali.

Yes it is for free

Google search gave a few results and one among them about it http://www.runscanner.net/lib/ntvdm.exe.html

shows ntvdm is a virus

Ayesha pls explain

M. Kechouane I need this software. We are working with thin films for OLED and Memristor devices.

Yes I gone thrught he website.

So, where is soft? :)

I have that software, I gone through that's properties, but no use, I could not find any details. By using C ++ a long program ......, particularly for oxide materials.

Ayesha mariam please give me the link of the software

Not to free downloading, it is written in C ++ language by computerscience M.Phil scholar, namely TC Plus.

Dear Junaid Ali, give me your email address and In will send you the software

Good Luck Junaid

For U also Kashif

So, free soft exist or not?.. :)

No We have to create by using C++ language

There exists easy to use software for that: Winspall

It is available for download here: http://www2.mpip-mainz.mpg.de/groups/knoll/software

A tutorial to use this software is available here: http://www.res-tec.de/tutorials/res-tec-tutorial-02.pdf

Good luck,

Maxim

Thank U

[email protected]

Appreciated.

I have just send you the program Exoptic.exe, you must first install Visual Basic (VB40) or VB60 in order to determine the optical parameters from a transmission spectrum (in .dat format), I added a file (E2006.dat) on which you can practice before you master it.

Best regards

Pls can I have this Exoptic.exe, program as well for evaluation of optical constant alumina thin film of about 50 nm since there was no interference fringes.

Hello Mohammed and Sriram, could you please send me the excel files to my email: [email protected]; [email protected]. thanks

Dera Mohammed Kechouane,

Please I need the software "Exoptic.exe". I'm working with thin films based on TCO.

Could you please send it to me?

Thank you

I have yet not got the email of the software. Exoptic.exe

please share it through email

[email protected]

Dear Junaid Ali, Mohamed El Jouad and Leke Olarinoye

I have just send you the program Exoptic.exe, you must first install Visual Basic (VB40) or VB60 in order to determine the optical parameters from a transmission spectrum (in .dat format), I added a file (E2006.dat) on which you can practice before you master it.

Best regards

Thank you very much Mohamed Kechouane