A kind of preparation method of front silver paste

Abstract

The invention relates to a preparation method of front silver paste. In the method, the organic carrier is prepared and maintained at 30-40°C, so that the organic carrier is in a low-viscosity colloidal state; in this low-viscosity colloidal state, the organic The carrier is mixed with other components of the silver paste, especially the solid powder, which is conducive to the uniform dispersion of the solid powder in the silver paste and avoids local agglomeration. In addition, this method pre-mixes the silver powder and glass powder to ensure the uniformity of the dispersion of the glass powder around the silver powder, and then adds the solid mixture formed by the silver powder and glass powder to the dispersed organic carrier to make the silver powder and glass The powders are each uniformly dispersed in the organic vehicle. Since the content of the additive is less than that of the mixture of silver powder and glass powder, this method also adds the additive to the organic vehicle first, and then adds the pre-mixed silver powder and glass powder to the organic vehicle, so it is beneficial to the additive in the silver paste. evenly dispersed.

Description

technical field [0001] The invention relates to a preparation method of silver paste, in particular to a preparation method of front silver paste. Background technique [0002] A solar cell is a semiconductor device that can convert solar energy into electrical energy. Under the condition of light, the solar cell will generate current, collect and transmit electricity through grid lines and electrodes. The front electrodes and grid lines of solar cells are generally made of conductive silver paste through high-speed and high-precision screen printing, low-temperature printing, and high-temperature sintering. Among the electronic pastes for solar cells, front-side silver pastes have the greatest impact on the efficiency of solar cells, and are mainly composed of four parts: silver powder, glass powder, additives and organic vehicles. [0003] There are many reports on the preparation methods of front-side silver paste, and the general method is: first prepare organic vehicle...

AI Technical Summary

Problems solved by technology

Due to the high solid content of the paste, if the organic carrier is mixed with glass powder and silver powder at room temperature, the high viscosity of the system will affect the uniformity of dispersion during mixing, and agglomeration between silver powder and glass powder is easy to occur, especially The reason is that hydrogen bonds will be formed between the surfaces of the glass powder to cause hard agglomeration, and the hard agglomeration is difficult to break up by mechanical means, which makes it difficult for the slurry to pass through the screen during the screen printing process and block the screen, thus affecting the battery's electrical capacity. Performance, so that the photoelectric efficiency is reduced, it is difficult to meet the requirements of high-efficiency solar cells