A polycrystalline silicon wafer is provided. The polycrystalline silicon wafer, includes a plurality of silicon grains, wherein the carbon content of the polycrystalline silicon wafer is greater than 4 ppma, and the resistivity of the polycrystalline silicon wafer is greater than or equal to 1.55 -cm.

A method of fabricating a poly-crystalline silicon ingot includes: (a) loading a nucleation promotion layer onto a bottom of a mold; (b) providing a silicon source on the nucleation promotion layer in the mold; (c) heating the mold until the silicon source is melted into a silicon melt completely; (d) controlling at least one thermal control parameter regarding the silicon melt continually to enable the silicon melt to nucleate on the nucleation promotion layer such that a plurality of silicon grains grow in the vertical direction; (e) controlling the at least one thermal control parameter to enable the plurality of the silicon grains to continuously grow with an average grain size increasing progressively in the vertical direction until entirety of the silicon melt is solidified to obtain the poly-crystalline silicon ingot, wherein the nucleation promotion layer is loaded by spreading a plurality of mono-Si particles over the bottom of the mold.

A solar cell according to an embodiment of the present disclosure includes a first passivation layer including a first aluminum oxide layer positioned on a first conductivity-type region composed of a polycrystalline silicon layer having an n-type conductivity and having hydrogen, and a first dielectric layer positioned on the first aluminum oxide layer and including a material different from the first aluminum oxide layer.

The present disclosure relates to the field of solar cell technologies. The present disclosure provides a solar cell and a manufacturing method therefor, a photovoltaic module, and a photovoltaic system. The solar cell includes: a substrate; a tunnel oxide layer stacked on a surface of the substrate, the tunnel oxide layer being an oxide layer including at least a silicon element and an oxygen element; and a polysilicon doped conductive layer stacked on a side of the tunnel oxide layer facing away from the substrate. The tunnel oxide layer is doped with a carbon element and a hydrogen element.

A method for producing a solar cell, in particular a silicon thin-film solar cell, wherein a TCO layer (3) is applied to a glass substrate (1) and at least one silicon layer (4, 5) is applied to the TCO layer (3). Before the TCO layer (3) is applied, electron radiation is applied to the glass substrate (1), such that a light-scattering layer (2) of the glass substrate (1) is produced, to which light-scattering layer the TCO layer (3) is applied. Alternatively or additionally, a first silicon layer (4) may be applied to the TCO layer (3), a laser radiation or electron radiation may be applied to the first silicon layer (4), and a second silicon layer (5) may be applied to the irradiated first silicon layer (4).

The ultraviolet sensor device comprises a semiconductor substrate, a dielectric layer above the substrate, a surface of the dielectric layer that is provided for the incidence of ultraviolet radiation, a floating gate electrode in the dielectric layer and an electrically conductive control gate electrode near the floating gate electrode. The control gate electrode is insulated from the floating gate electrode. A sensor layer is formed by an electrically conductive further layer that is electrically conductively connected to the floating gate electrode. The control gate electrode is arranged outside a region that is located between the sensor layer and the surface provided for the incidence of ultraviolet radiation. The sensor layer is discharged by incident UV radiation and can be charged or discharged electrically by charging or discharging the floating gate electrode.

Methods of fabricating solar cell emitter regions using self-aligned implant and cap, and the resulting solar cells, are described. In an example, a method of fabricating an emitter region of a solar cell involves forming a silicon layer above a substrate. The method also involves implanting, through a stencil mask, dopant impurity atoms in the silicon layer to form implanted regions of the silicon layer with adjacent non-implanted regions. The method also involves forming, through the stencil mask, a capping layer on and substantially in alignment with the implanted regions of the silicon layer. The method also involves removing the non-implanted regions of the silicon layer, wherein the capping layer protects the implanted regions of the silicon layer during the removing. The method also involves annealing the implanted regions of the silicon layer to form doped polycrystalline silicon emitter regions.

A solar cell according to an embodiment of the present disclosure includes a first passivation layer including a first aluminum oxide layer positioned on a first conductivity-type region composed of a polycrystalline silicon layer having an n-type conductivity and having hydrogen, and a first dielectric layer positioned on the first aluminum oxide layer and including a material different from the first aluminum oxide layer.

The present disclosure relates to a heterojunction solar cell, a manufacturing method thereof and a photovoltaic module. The heterojunction solar cell includes a substrate of a first conductivity type, a tunnel layer located on a light-receiving surface of the substrate, and a doped polysilicon layer located on a top surface of the tunnel layer. The doped polysilicon layer has the first conductivity type.

A process for producing silicon which comprises: bringing molten silicon containing an impurity into contact with molten salt in a vessel to react the impurity contained in the molten silicon with the molten salt; removing the impurity from the system.