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I have absorbance (Abs), reflectance (R%) and transmittance (T%) data of TiO2 deposited thin film on FTO glass substrate. The data was collected using UV-Vis spectrophotometer. Also, I know the thickness of the thin film and substratre.

How to calculate refractive index n of TiO₂ from this?
If you know a simple way, kindly suggest how to proceed.

User Brianskold
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1 Answer

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Final answer:

To calculate the refractive index of TiO2 from UV-Vis spectrophotometry data, one can use Swanepoel's method, which involves analyzing transmittance spectra, applying thin-film interference equations, and considering the known film thickness.

Step-by-step explanation:

To calculate the refractive index (n) of a TiO2 thin film using absorbance (A), reflectance (R%), and transmittance (T%) data collected from a UV-Vis spectrophotometer, you may apply the Swanepoel's method. This method is a common technique for characterizing thin film optical properties. However, it is not straightforward and will require some understanding of optical interference and the complex refractive index. Here's a simplified guide:

  • Note the known thickness of the TiO2 film and the glass substrate.
  • Identify the wavelengths where maxima and minima occur in the transmittance spectrum.
  • Using the maxima and minima from the transmittance spectrum, you can calculate the envelope functions which give you the required data to find the refractive index.
  • Apply the equations of thin-film interference, considering the phase shift upon reflection, to determine the refractive index of the film.

Keep in mind this process involves several steps and calculations, including the use of the Fresnel equations and may involve iterative calculations or curve fitting techniques to obtain accurate results. Consulting a detailed text on optical properties of thin films would be useful for a full understanding and accurate computation.

User Sbz
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