Resumen
[0001] A relevant technological challenge is the low cost and abundant materials development for silicon surface passivation for applications in optoelectronic devices, in particular in solar cells by scalable industrial methods. In the present invention, a new hybrid material comprising PEDOT:PSS and transparent conducting oxide nanostructures is developed and a method is proposed to fabricate the composite material that passivates well the silicon surface to be used by means of a thin composite film of thickness below 200 nm.
Reivindicaciones
1. Hybrid organic-inorganic material consisting of an organic conductor polymer matrix and transparent conducting oxide nanostructures as filler, where the conductive polymer is PEDOT:PSS and the nanostructures are dispersed in the polymer in a ratio of 0.1 - 10 % wt., characterized in that said nanostructures have tin and /or titanium oxide nanowires undoped or doped with Cr, Al, or Li with a cationic percentage range of 1 to 40% and the nanowires have sections of up to a 100 nm and lengths of up to 1000 nm. 2. The hybrid organic-inorganic material according to claim 1, wherein said ratio is a ratio of 0.25% - 5 % wt. 3. The hybrid organic-inorganic material according to claim 1 or 2, wherein said cationic percentage range is a range of 1 to 30 %. 4. The hybrid organic-inorganic material, as claimed in any one of claims 1-3, having a mixture with controlled ratios of the tin and /or titanium oxide nanowires. 5. Hybrid organic-inorganic material consisting of an organic conductor polymer matrix and transparent conducting oxide nanostructures as filler, where the conductive polymer is PEDOT:PSS and the nanostructures are dispersed in the polymer in a ratio of 0.1 - 10 % wt., characterized in that said nanostructures have Si nanowires, Al<2>O<3> nanowires, SiN<x> nanowires, or a mixture thereof, wherein the nanowires are undoped or doped with Cr, Al, or Li with a cationic percentage range of 1 to 40% and the nanowires have sections of up to a 100 nm and lengths of up to 1000 nm. 6. The hybrid organic-inorganic material, as claimed in claims 1 to 5, having Ethylene Glycol as dispersant added to the dispersion of the organic conductor. 7. Passivation method comprising the deposition of a hybrid composite by spin coating technique of one or several layers of the hybrid material according to any one of claims 1-6 over a substrate to be passivated, and subsequent water removal, wherein said substrate to be passivated consists of untreated type p or type n silicon coated with silicon dioxide, and fabricating said hybrid composite, comprises at least the steps of: - providing an aqueous dispersion of PEDOT:PSS conductive polymer. - providing transparent conducting oxide nanostructure as defined in claim 1 or 5 with controlled size and doping by techniques, - adding the nanostructures in the ratios lower than 10% wt at the aqueous dispersion under ultra-sonication. 8. Passivation method as claimed in 7, where the water is removed by a thermal treatment, at a temperature range of 100-130 °C during 10 to 30 minutes. 9. Passivation method according to claim 8, wherein the water is removed at a temperature range of 110-125 °C. 10. Passivation method according to claim 8 or 9, wherein the water is removed during 15 to 25 minutes. 11. Passivation method as claimed in 7, where the deposited layer has a thickness below 200 nm. 12. Passivation method according to claim 11, where the deposited layer has a thickness in a range of 90-150 nm. 13. Passivation method as claimed in claim 7, having an isopropanol treatment of the silicon substrate to increase the hydrophilic character of the substrate.
