**3. Ellipsometric spectroscopy measurement**

Spectroscopic ellipsometry is a very sensitive optical surface analysis method that allows the physical and morphological properties of a flat sample to be probed at different scales and at different energies. It has experienced significant growth over the past 100 years [38] and particularly over the past 20 years with modern computing. The

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**Figure 11.**

**Figure 10.**

*The multilayer model of the PSL [31].*

*Real photo of the GES 5 Sopra Ellipsometry used in our work.*

*Optical Study of Porous Silicon Layers Produced Electrochemically for Photovoltaic Application*

technique makes it possible to obtain information on the surface of a massive sample, on the volume of a thin film or even on the interfaces. Ellipsometry has the advantage of being very simple and quick to implement, nondestructive, of allowing in-situ and

Ellipsometric measurements were performed on the porous silicon substrate for an angle of incidence of 78° in the spectral range 250–2000 nm using the GES5 Sopra made rotating polarizer spectroscopic ellipsometer was used for the (SE) spectroscopic ellipsometry measurement, controlled by the WinElli-II software. To extract the thickness of the PS layer from measuring of SE, an optical model must be assumed, as well as the calculated data have to follow experimental spectra. In applying EMA software, we utilized a model of a multi-layer model, whereas the first mixture of the layer (void/SiO2), while the second layer is (Sic/void), As indicated in **Figure 10**, a high improvement in the fit quality was observed [31].

**Figure 11** shows the "GES5" spectroscopic ellipsometer used in our work; this ellipsometer is assisted by a computer and controlled by the WinElli-II software.

real-time monitoring, and being applicable to a very wide range of samples.

*DOI: http://dx.doi.org/10.5772/intechopen.93720*

**3.1 Expérimental details**

**3.2 Experimental device used**

*Optical Study of Porous Silicon Layers Produced Electrochemically for Photovoltaic Application DOI: http://dx.doi.org/10.5772/intechopen.93720*

technique makes it possible to obtain information on the surface of a massive sample, on the volume of a thin film or even on the interfaces. Ellipsometry has the advantage of being very simple and quick to implement, nondestructive, of allowing in-situ and real-time monitoring, and being applicable to a very wide range of samples.
