**Author details**

Rahmouni Salah1,2

1 Higher School for Professor of Technological Education, ENSET, Skikda, Algeria

2 Laboratory of Physical Chemistry and Biology of Materials (LPCBM), ENSET, Skikda, Algeria

\*Address all correspondence to: rahmouni.eln@gmail.com

© 2020 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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*Solar Cells - Theory, Materials and Recent Advances*

78%, we get n = 1.22 and k = 0.0014 [31].

the porous layers.

**Figure 16.**

**4. Conclusion**

photovoltaic field.

**3.5 Calculation of the refractive index (n) and the extinction coefficient (k)**

*Variation of refractive index and extinction coefficient as a function of porosity [31].*

The results illustrated in **Table 3** and **Figure 16** show that the refractive index and the extinction coefficient are as a decreased function along with the porosity. In case of a porosity of 34%, we get n = 1.77 and k = 0.0035, while for porosity of

This result shows that the remained porous layer is more proper, but less thick and gives us a best PL intensity. Hence, the laser diffuses in wells by confinement effect. This confinement means to confine the incident laser radiation in crystallites seals and therefore the laser reflection is reduced following the big values of thickness and

In this study, we developed porous silicon layers by electrochemical anodization, the optical characterization made by spectroscopic ellipsometry (SE), and photoluminescence (PL); this characterization enabled us to calculate the physical and optical parameters (porosity, thickness; refractive index, extinction coefficient). To determine the effect of the etching parameters, we have suggested that for a good elaboration of the porous layers, it would be necessary to know the optimal conditions of anodization, taking into account the great role of the oxide layer on the surface. We note that the results obtained demonstrate that it excites a correlation between photoluminescence characterization (PL) and measurement of spectroscopic ellipsometry (SE), and these results are very important in the
