Please anyone can explain how to analyze Spectroscopic ellipsometry data for a-Si:H films ? band gap, thickness and refractive index etc ? which model will suitable and how to fit with that model ? I am using semilab (Sopra ) ellipsometer.
I am not sure on how experienced you are on spectroscopic ellipsometry data measurement and analysis. I use J A Woolam systems and hope the analysis is similar. This is a bit long to explain so I will skip some details. One way of doing it in WVASE 32 is; Start with a Genosc.mat ,open ref mat and fit e2 only to ref. Add tauc-lorentz oscillator and fit Amp, En, C and Eg . Then select Fit e1 only to ref and fit pole #1 & #2 and e1 off-set. You can then select fit both to view the fitted e1 & e2. You can the save the optical parameters. Using the defaults settings, you can display your results in wavelengths, wavenumbers or photon enegies (eV). You can also toggle the display graphs by holding down ctrl and T or Ctrl+Shit and T for display in reverse direction. This procedure is slightly different if you use the CompleteEasy software.Let me know if you need more info.
For a-Si:H, use a single Cody-Lorentz oscillator. A Tauc-Lorentz oscillator can also be used.
Dear Sir,
You can use the Tauc-Lorentz oscillator - when you add this to the model in the Semilab software, it has the default parameters for a-Si. The Tauc-Lorentz dispersion law has the Eg (optical band-gap) as parameter. The Cody-Lorentz is also a possibility in the software. Please, feel free to send me your measurement spectra if you need assistance or optimization of your model.
Peter Basa Sir, i attached here measure pae file, film:a-Si:H, Substrate: crystalline Si, incident angle is 70 degree, im unable fit this spectra, i need to find band gap, refractive index , thickness and also imaginary part of dielectric constant(epsillon(i) vs energy). in Tauc Lorentz model how to choose A, C, E0 other parameters?
- Badges
- Science topic