Double-layer reflection-decreasing film for silicon solar cell and preparation method thereof

Abstract

The invention relates to a double-layer antireflecting film of a silicon solar cell and a preparation method thereof. A layer of a silicon nitride film (2.1) is deposited on the positive surface of a silicon chip underlayer (1); and a layer of a silicon dioxide film (2.2) is deposited on the silicon nitride film (2.1) to form a silicon nitride / silicon dioxide double-layer reflecting film (2). Themethod comprises: step one, SiH4 and NH4 react on the silicon chip underlayer manufactured with wool to deposit a layer of the silicon nitride film through a plasma enhanced chemical vapor depositionmethod; and step two, SiH4 and N2O react on the silicon nitride film to deposit a layer of the silicon dioxide film through the plasma enhanced chemical vapor deposition method. Compared with the prior monolayer antireflecting film, the double-layer antireflecting film has smaller refractive index and improves the cell efficiency. The method can be completed in the same equipment and simplifies the process and the equipment.

Description

(1) Technical field [0001] The invention relates to a double-layer anti-reflection film for silicon solar cells used in solar cells and a preparation method thereof. It belongs to the technical field of solar cells. (2) Background technology [0002] When light hits a flat solar cell silicon wafer, part of it will be reflected and cannot enter the solar cell. Even for a textured silicon surface, there is a reflection loss of about 11%. Covering a layer of anti-reflection film on the silicon wafer can reduce the reflection of light, thereby increasing the efficiency of the battery. At present, most monocrystalline silicon solar cells use a layer of silicon nitride film as an anti-reflection system in industrial production, and the silicon nitride film can also play a passivation role. According to the λ / 4 anti-reflection principle, by adjusting the thickness of the silicon nitride film, the reflectivity can be minimized near the central wavelength, thereby maximizing the ef...

AI Technical Summary

Problems solved by technology

[0002] When light hits a flat solar cell silicon wafer, part of it will be reflected and cannot enter the solar cell. Even for a textured silicon surface, there is a reflection loss of about 11%.

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