Method of fabricating a silicon solar cell

Abstract

A method of fabricating a back surface point contact silicon solar cell having p-doped regions and n-doped regions on the same side by forming a passivating layer on a surface of the cell having opened windows at the p-doped regions and the n-doped regions, by depositing and patterning a first metal layer on the passivating layer in such a way that the first metal layer comes into contact with the p-doped regions and the n-doped regions, by depositing an insulator layer of polyimide on the first metal layer, by etching and patterning the insulator layer of polyimide in such a way that the insulator layer has opened windows at, at least one of the p-doped regions and the n-doped regions, by curing the insulator layer of polyimide by heating at temperature for a period, by additionally curing the insulator layer of polyimide by heating at a second temperature, which is higher than the first temperature, and by depositing a second metal layer made of metal stack on the insulator layer of polyimide in such a way that the second metal layer comes into contact with the one of the p-doped regions and the n-doped regions. With this, the cell surface to be soldered onto a metallized substrate is well planarized and even to ensure sufficient conductibility, with less voids and less solder fatigue.