Back contact type black silicon cell and preparing method thereof

Abstract

The invention belongs to the field of photovoltaic technology, and particularly relates to a preparing method of a back contact type black silicon cell. High-absorptivity black silicon is prepared through silver nanoparticle induced chemical corrosion, absorption of a silicon wafer in the range of 700-1500 nm can be effectively promoted by the back silicon on the back surface, and the surface texturing technology is adopted for the illuminated surface. Generated 300-1500 nm broad-spectrum photoelectron holes can be effectively used by a PN junction region of an IBC structure, and the photocurrent is far larger than that of a common crystalline silicon solar cell. The novel IBC structure uses the broad-spectrum absorption effect of the black silicon and the advantage of the back contact photovoltaic junction region at the same time, fundamentally broadens spectral response of the crystalline silicon solar cell, breaks through the theory efficiency limit 29% of a narrow-band crystallinesilicon cell, fully uses infrared light occupying nearly half of the sunlight energy spectrum and breaks through the bottleneck of the crystalline silicon process in recent 20 years.

Description

technical field [0001] The invention belongs to the technical field of photovoltaics, and in particular relates to a back contact type (IBC) black silicon battery and a preparation method thereof. Background technique [0002] Silicon solar cells are long-term and will continue to occupy a dominant position in the photovoltaic industry in the future. However, the research work on silicon solar cells has encountered unprecedented challenges, mainly because today's mainstream silicon photovoltaic technology still focuses on narrow spectral response, and various The process and its synergistic effects have tapped the potential of the narrow-band photoelectric response corresponding to the silicon band gap to the limit. The theoretical limit efficiency of narrow-band cells is about 29%. (HIT) (25.6%) The process is extremely complicated and the cost is quite high. In the process of mass production, limited by the process conditions and various other factors, the actual efficie...

AI Technical Summary

Problems solved by technology

The black silicon battery was born in the 1990s. One of the major disadvantages is that the source of impurities that produce high infrared absorption is relatively close to the PN junction, resulting in a low open circuit voltage of the black silicon battery.

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