It does not matter how you fabricate the surface. I only want to have a physical feeling on how big the reflectance can be. Or if someone has a physical equation to show me, well that's even better.
well if you consider a deposited coating to be anti reflective, you should take into account that the reflectivity is depending on the light wavelength of incident photons on the dielectric, and absorption of your material. We normally talk about the minimum of reflectivity at a certain wavelength of light. In the case of solar cells the deposited coating (SiN) should have minimum reflectivity at 600 nm, which is the maxima of the solar spectrum.
Thank you for your answer Dr Urrejola.
Can I dare to ask you to be even more specific? If we talk about numbers, how much percentage of the initial reflectance (before the coating) is the critical number for a surface to be considered non-reflective? What is the percentage of reflected light of the surface coated with SiN or any other anti-reflective coating (5%, 3%, 1% or less-more?)??
Dear Dimitrios, if I got your point, and if you are talking about solar cell devices, here my answer: at a wavelength of 600 nm (maximum number of incident photons from sun spectrum on your device) the reflectivity of your ARC should be ZERO --> maximum light trapping --> maximum photogenerated current in your device. But at the rear surface the reflectivity should be higher --> you don't want light going trough your device (ideal case reflectivity of the front surface ZERO, rear reflectivity 100%)
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