Abstract: The present invention provides a method for dielectric passivating the surface of a solar cell by accumulation of negative fixed charges of a first type at the interface between semiconductor material and a passivating material. According to the invention the passivating material comprises an oxide system, for example a binary oxide system, comprising Al2O3 and at least one metal oxide or metalloid oxide which enhances the tetrahedral structure of Al2O3, for example, an (Al2O3)x(TiO2)1-x alloy. In this way it is possible to combine the desirable properties from at least two different oxides, while eliminating the undesirable properties of each individual material. The oxide system can be deposited onto the semiconductor surface by means of a sol-gel method, comprising the steps of formation of the metal oxide and/or metalloid oxide sol and the aluminum solution and then carefully mixing these together under stirring and ultrasonic treatment.

Abstract: A method for the production of a photovoltaic device, for instance a solar cell, is disclosed. In one aspect, the method comprises providing a substrate having a front main surface and a rear surface. The method further comprises depositing a dielectric layer on the rear surface, wherein the dielectric layer has a thickness larger than about 100 nm. The method further comprises depositing a passivation layer comprising hydrogenated SiN on top of the dielectric layer and forming back contacts through the dielectric layer and the passivation layer. In another aspect, corresponding photovoltaic devices, for instance solar cell devices, are also disclosed.

Abstract: The present invention provides a method for dielectric passivating the surface of a solar cell by accumulation of negative fixed charges of a first type at the interface between semiconductor material and a passivating material. According to the invention the passivating material comprises an oxide system, for example a binary oxide system, comprising Al2O3 and at least one metal oxide or metalloid oxide which enhances the tetrahedral structure of Al2O3, for example, an (Al2O3)x(TiO2)1-x alloy. In this way it is possible to combine the desirable properties from at least two different oxides, while eliminating the undesirable properties of each individual material. The oxide system can be deposited onto the semiconductor surface by means of a sol-gel method, comprising the steps of formation of the metal oxide and/or metalloid oxide sol and the aluminum solution and then carefully mixing these together under stirring and ultrasonic treatment.