Ion Shower Doping Technique for Selective Emitter Structure in Crystalline Silicon Solar Cells

Abstract

For realizing low-cost and high-conversion-efficiency silicon solar cells, we propose an ion shower doping technique for fabricating conventional and selective emitter structure solar cells. Because of its high through put with a large beam area, the technique could lead to low-cost production of the emitter layer. We used this technique to form a uniform emitter layer and also a selective high-doping emitter region for silicon solar cells, which were compared with cells prepared by POCl3 diffusion. The conventional structure cells were confirmed to have good electrical properties with uniform conversion efficiency compared with the cells prepared by POCl3 diffusion. There was no doping-induced damage nor metal impurities interfused during the ion shower doping. In addition, the conversion efficiency of selective emitter structure cells was higher than that of cell prepared by POCl3 diffusion only. We concluded that the ion shower doping technique is useful for forming a uniform emitter layer as well as a selective emitter region.

PC2D simulation and optimization of the selective emitter solar cells fabricated by screen printing phosphoric paste method

“…1) Due to the advantages of good compatibility to the existing crystalline silicon (c-Si) solar cell technology and the ability to significantly increase the efficiency, the SE solar cell has become a very hot research topic in last few years. 2,3) Many different methods for preparing SE solar cells have been studied, such as laser doping, [4][5][6][7][8][9][10] etch-back, 11,12) screen printing doping source, [13][14][15][16][17][18] ion implantation [19][20][21] and dielectric mask process. [22][23][24] Among various SE solar cell technologies, the screen printing phosphoric paste (SPPP) method may be the one of the most promising industrialization technologies, [13][14][15][16][17][18] since it can obtain at least 0.5% efficiency increment against the homogeneous emitter (HE) solar cell without remarkably increasing the cost by only adding a phosphoric paste screen printing and drying step in the conventional c-Si solar cell process.…”