Back contact forming method of passivated emitter and rear contact solar cell

Abstract

The invention discloses a back contact forming method of a passivated emitter and rear contact solar cell. The back contact forming method of the passivated emitter and rear contact solar cell comprises the following steps that (1) a light trapping mechanism is formed on the obverse side of a cell substrate of a first conduction type; (2) doping of a second conduction type is carried out on the obverse side of the cell substrate; (3) an antireflection layer is formed on the obverse side of the cell substrate in a deposition mode; (4) a mask plate is arranged on the top of the back side of the cell substrate; (5) a back passivating dielectric layer is formed on the back side of the cell substrate, and an exposed area, without the passivating dielectric layer, of the back side is formed at the same time; (6) electrode patterns are formed on the back side and the obverse side of the cell substrate respectively, and ohmic contact between electrode metal and silicon is formed in a high-temperature sintering mode. According to the back contact forming method of the passivated emitter and rear contact solar cell, damage caused by laser windowing in the preparation process of the passivated emitter and rear contact solar cell can be eliminated, conversion efficiency of the passivated emitter and rear contact solar cell is improved, the preparation cost of the passivated emitter and rear contact solar cell is reduced, and the risk of the fragmentation rate of module preparation is reduced.

Description

technical field [0001] The invention relates to the preparation of PERC (Passivated emitter and rear contact) solar cell with passivation on the back, and relates to a method for forming the back electrode contact of the PERC solar cell. Background technique [0002] Existing formation of rear passivation solar cell PERC, such as figure 1 As shown, it includes a front electrode 1 , an anti-reflection layer 2 , an emitter 3 , an aluminum-silicon contact 4 , a rear passivation layer 5 , aluminum 6 , and a window area 7 on the rear passivation layer 5 . Generally, after depositing the anti-reflection layer on the front side of the back passivation battery, a passivation layer is deposited on the back side, and the passivation layer uniformly covers the entire area of ​​the back side. Existing methods for forming PERC rear contacts of rear-passivated solar cells generally include laser ablation window opening, chemical mask etching window opening, and photolithography window op...

AI Technical Summary

Problems solved by technology

Generally, the rear passivated solar cells have problems such as high rear recombination rate caused by laser technology or poor rear pattern accuracy caused by chemical corrosion process, cell conversion efficiency cannot be greatly improved, and lithography production costs are too high.

Images