化学抛光对硅基异质结太阳电池性能的影响

Influence of Chemical Polishing on Performances of Silicon Heterojunction Solar Cells

针对非晶硅薄膜沉积时金字塔沟壑处容易出现外延生长的问题,采用化学抛光液CP133对硅片表面进行了抛光处理。研究结果表明,抛光使得金字塔底部区域形貌由"V"型变成了"U"型,明显改善了非晶硅/晶体硅界面的钝化效果。抛光溶液温度低于30℃时难以发挥腐蚀作用,但当溶液的起始温度升高至35℃时,获得了较好的抛光效果。采用质量分数为1%的NaOH溶液制绒且抛光时间为30s时,太阳电池性能较佳。

Aiming to avoid the local epitaxial growth of amorphous silicon films in the pyramidal valleys of the textured silicon wafers, a chemical polishing mixture named CP133 is used to polish the textured crystalline silicon (c-Si) surfaces. The research results show that the morphologies of the pyramidal valleys change from V shape to U shape, which clearly improves the passivation effect at the hydrogenated amorphous silicon/crystalline silicon interface. When the temperature is lower than 30 ℃, the solution is difficult to react with the crystalline silicon. However, the problem can be solved by the increase of the solution temperature up to 35 ℃. The performance of the solar cells is relatively good when the polishing time is 30 s and the NaOH texturing solution has a mass fraction of 1%.