IBC cell manufacturing method

Abstract

The invention discloses an IBC cell manufacturing method. The method comprises the following steps of carrying out texture surface making; depositing a diffusion mask layer; making a back side P+ definition area; carrying out P+ area boron diffusion to form a back junction; removing a residual diffusion mask layer on a silicon chip surface; printing a phosphor doping slurry on an N+ doped area defined on a silicon chip back side; manufacturing a front surface field; under a high temperature condition, using POCL3 to form the front surface field on an upper surface of the silicon chip, wherein the phosphor doping slurry enters into a substrate to form an N+ area under the high temperature condition during a process that the POCL3 is used to carry out phosphorous diffusion so as to form the front surface field; depositing a passivation reduction reflecting layer on a front side and a back side of the silicon chip; and making a metal electrode. In the method, a phosphorus diffusion technology only needs to be performed once and front field and back field areas possessing different doped concentrations can be synchronously manufactured; and a making technology process of an IBC cell is simplified and production cost is reduced, which is convenient for large-scale popularization.

Description

technical field [0001] The invention relates to the technical field of preparation methods of solar cells, in particular to a preparation method of an IBC battery. Background technique [0002] The IBC (interdigitated back contact) battery appeared in the 1970s and was the earliest researched back-junction battery. It was mainly used in concentrating systems at first. The battery is made of N-type substrate material, and the front and rear surfaces are covered with a layer of thermal oxide film to reduce surface recombination. In the manufacturing process, it is necessary to use photolithography technology to perform local diffusion of phosphorus and boron on the back of the battery, forming a P region, an N region arranged in a finger-like cross arrangement, and a P+ region and an N+ region above it. Compared with conventional solar cells, the advantages of IBC batteries are mainly manifested in the following aspects: (1) The positive and negative electrodes of the battery...

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Problems solved by technology

(4) The matrix material of IBC cells is generally N-type crystalline silicon, and the boron content of the N-type matrix is ​​low, so the light-induced attenuation caused by the boron-oxygen pair is not as obvious as that of the P-type matrix material, and the efficiency of the packaged components is significantly improved.

[0004] The back cross structure of the conventional IBC battery is to use photolithography technology to perform partial diffusion of phosphorus and boron on the back of the battery to form interdigitated interdigitated P regions and N regions. This method has poor controllability and cannot be precisely Control the process

In addition, the cost of photolithography technology is high, and high-temperature diffusion requires multiple mask protection and high-temperature processes. There are many steps and the operation process is difficult.

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