An N-type crystalline silicon solar cell based on doped polysilicon germanium thin film and a preparation method thereof

Abstract

The invention relates to an N-type crystalline silicon solar cell based on doped polycrystalline silicon germanium thin film and a preparation method thereof, wherein the N-type crystalline silicon wafer is velvet on both sides, Double-sided boron is then diffuse on that front surface to form an emitter, An oxide tunneling layer is prepared by alkali throwing on the back surface, Then N + polysilicon germanium thin films were prepared by reactive thermal CVD at low temperature below 350oC to form back tunneling oxide passivation contact structure. Then emitter passivation film and front and back antireflection film were prepared. Finally metal gate line electrodes were prepared in front and back of the cell. A low-temperature process is adopted to prepare that N + polycrystalline silicon germanium film on the back surface of the invention, which not only avoid the damage of the tunneling oxide layer caused by the high-temperature process, but also can obtain the polycrystalline silicongermanium film with higher crystalline quality, effectively improve the doping concentration and the carrier mobility of the film, and is beneficial to improving the filling factor and the conversionefficiency of the battery.

Description

technical field [0001] The invention belongs to the field of solar cells, and in particular relates to an N-type double-sided high-efficiency crystalline silicon solar cell and a preparation method thereof. Background technique [0002] With the continuous development of photovoltaic technology, photovoltaic cells with high efficiency, high stability and low cost will become the mainstream products pursued by the photovoltaic market. Compared with P-type crystalline silicon solar cells, N-type crystalline silicon solar cells have the advantages of high conversion efficiency, low light-induced attenuation, and good stability, and are receiving more and more attention in the photovoltaic market. [0003] How to further improve the conversion efficiency of cells and reduce costs has become a difficult problem for many researchers in the photovoltaic industry, and it is also the core goal pursued by the industry. Through the analysis of the working principle and efficiency loss...

AI Technical Summary

Problems solved by technology

This high-temperature activation process not only leads to the degradation of the substrate quality, but also easily destroys the tunnel oxide layer, which affects the passivation effect of the silicon substrate surface.

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