Processing technology of IBC battery with passivation contact structure

Abstract

The invention is applicable to the technical field of solar cells, and provides a processing technology of an IBC battery with a passivation contact structure. The technology comprises the following steps: texturing and polishing an N-type monocrystalline silicon wafer, growing a tunneling oxide layer on the back surface, depositing P-type/N-type doped polycrystalline silicon on the back surface, performing phosphorus diffusion on the front surface, depositing an antireflection layer on the front surface, and depositing a passivation layer on the back surface; etching the passivation layer at the position of the P-type/N-type doped polycrystalline silicon printing grid line by using laser ablation to form a groove; utilizing silver paste to carry out silk-screen printing on grid lines in the groove corresponding to the P-type/N-type doped polycrystalline silicon at one time; and sintering at a low temperature of 400-690 DEG C to obtain a battery finished product. According to the processing technology of the IBC battery with the passivation contact structure, the groove is etched at the position of the P-type/N-type doped polycrystalline silicon printing grid line through laser ablation, ohmic contact between the grid line and the polycrystalline silicon can be achieved through low-temperature sintering, damage to the polycrystalline silicon and the tunneling oxide layer is avoided, the passivation effect of the battery is ensured, and metal induced recombination in a grid line area is reduced, and the battery efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of solar cell processing, in particular to a processing technology of an IBC cell with a passivation contact structure. Background technique [0002] With the development of solar cell technology, more and more attention has been paid to the reliability of solar cells. Among them, the IBC (Interdigitated back contact) battery is a solar cell in which both P-type doped polysilicon and N-type doped polysilicon are placed on the back of the battery. In order to reduce the surface recombination rate of the battery, the general IBC battery usually uses silicon nitride , silicon dioxide and other films for surface passivation, the use of passivation structure can reduce the surface recombination rate, which is helpful to increase the open circuit voltage. [0003] In the prior art, the processing technology of an IBC battery with a passivated contact structure is usually: N-type monocrystalline silicon wafers are...

AI Technical Summary

Problems solved by technology

[0005] The invention provides a processing technology for an IBC battery with a passivation contact structure, aiming at solving the problem of using a high-temperature sintering slurry to etch the passivation layer to realize the ohmic contact between the gate line and the polysilicon in the IBC battery with a passivation contact structure in the prior art. There is a problem that the high-temperature paste is easy to damage the tunnel oxide layer and reduce the passivation effect of the battery, and the high-temperature paste is easy to damage the polysilicon, which leads to the increase of metal-induced recombination in the gate line area and reduces the battery efficiency.

Images