N-type battery structure and preparation method thereof

Abstract

The invention discloses an N-type battery structure and a preparation method thereof. The structure comprises an N-type silicon body material and a metal grid line electrode formed on the surface of the N-type silicon body material, and is characterized in that the back surface of the N-type silicon body material is provided with a suede part and a polished surface part, and the contact position of the metal grid line electrode and the N-type silicon body material is located in the suede part. The back metal grid line electrode adopts a suede structure, so the contact area between the metal grid line and silicon is increased, and the contact resistance is improved; the flat surface of the polished area can improve the back passivation effect, reduce the surface recombination rate, enhance the internal reflection of long waves and improve the front current.

Description

technical field

[0001] The invention relates to the technical field of solar cells, and relates to an N-type cell structure and a preparation method thereof. Background technique

[0002] With the development of solar cell technology, cell efficiency is increasing day by day, mainly due to the development of surface passivation technology. Composite on the back surface of the battery. The development of PERC cells to TOPcon cells benefits from the passivation effect of the tunneling oxide layer and poly film structure on metal contacts, which greatly reduces the recombination under the back metal contacts. With the decreasing surface recombination rate, the lifetime of bulk materials has gradually become a key factor restricting the improvement of battery efficiency. Compared with the P-type doped silicon material, the N-type doped silicon material has a lower doping concentration and less impurity content under the same resistivity, so it has the advantage of long life. ...

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