Investigation of nano-porous silicon antireflection coatings for crystalline silicon solar cells

Reflectance loss of crystalline Si causes low efficiency. The optical loss can reduce by antireflection coatings (AR coatings). The porous silicon (PSi) formed by anodization is well known as using good ARC because PSi can be obtained easily and economically. So, we investigated PSi as AR coating for silicon solar cells. The nano-PSi was obtained by electrochemical etching and has reflectance less than 20% in wavelength for 450-1000 nm. The porosity is about 60% and refractive index is 1.7. The obtained results point out that it would be possible to apply a Si solar cell by the proposed simple technology.