Heterojunction solar battery composed of amorphous silicon/crystalline silicon/beta-FeSi2

Abstract

The invention discloses a heterojunction solar battery composed of amorphous silicon / crystalline silicon / beta-FeSi2, and is characterized in that the heterojunction solar battery comprises an illuminated surface electrode, a transparent conducting layer, a p+ type amorphous silicon layer, a p type crystalline silicon layer, an i type beta-FeSi2 layer, an n+ type amorphous silicon layer and a back metal electrode which are laminated and combined to form a P+PIN+ heterojunction structure. According to the solar battery, the amorphous silicon layer has wide forbidden bandwidth, good surface passivation is formed on the battery surface, the open-circuit voltage of the battery is increased, the temperature coefficient is reduced, and the high temperature performance is obviously improved; the beta-F2Si2 with a narrow band gap and crystalline silicon are used as light absorption layers at the same time, thereby effectively expanding the spectral response range, particularly long-wave band light response of a crystalline silicon battery, and improves short-circuit current of the battery; and since the light absorption coefficient of beta-FeSi2 is high, the required thickness is small, the thickness of the crystalline silicon layer can be further reduced, and material costs are reduced.

Description

technical field [0001] The invention relates to a solar cell with a new structure, especially a solar cell made of amorphous silicon / crystalline silicon / β-FeSi 2 composed of heterojunction solar cells. Background technique [0002] Silicon heterojunction solar cells deposit a layer of amorphous silicon on the crystalline silicon substrate as the emission area, which effectively avoids the high-temperature diffusion process of traditional crystalline silicon cells, reduces thermal damage to silicon wafers, and reduces energy consumption. , The amorphous silicon film can also form a good passivation on the surface of the silicon wafer, obtain higher open circuit voltage and conversion efficiency, and the temperature coefficient is also smaller, and the high temperature performance of the battery is better. Silicon heterojunction solar cells are made of crystalline silicon materials with a band gap of 1.12eV. During the photoelectric conversion process, photons with energy gre...

AI Technical Summary

Problems solved by technology

Although it has long been recognized that β-FeSi 2 It can be applied to solar cells, but the conversion efficiency has not been high. The reason is that it is difficult to achieve a high enough built-in potential and open circuit voltage with a simple PN heterojunction composed of FeSi2 / Si, and because β-FeSi 2 It is difficult to achieve effective controllable doping, so its photoelectric conversion efficiency is difficult to reach the level of crystalline silicon cells

Images