等离子体刻蚀对CdTe太阳电池性能的影响

Influence of plasma etching on the performance of CdTe solar cells

采用不同干法腐蚀条件下的CdTe薄膜制成器件,通过I-V、C-V和光谱响应等测试了电池性能参数。结果表明,溅射时间太短和功率太小时不能完全去除氧化层,溅射时间过长和功率过高会对薄膜表面造成损伤,影响器件性能。通过选择器件性能较好的电池、找出适合等离子束溅射工艺的条件,所制成的电池转化效率达到10.99%;而湿法腐蚀所制成器件的转化效率为10.26%。由此可以认为,等离子束轰击溅射的腐蚀方法较湿法腐蚀更适用于CdTe太阳电池的制备。

In order to find suitable etching conditions for CdTe thin films in industrial production, different dry etching conditions are applied to CdTe solar cells in this paper. The performance parameters of J-V, C-V and spectral response are studied. It is indicated that the time and the power of plasma etching are too small to completely remove the oxide layer. On the contrary,the surface is damaged too seriously and the devicels performance decreases. Estimated by the I-V characteristics, C-V characteristics and spectral response of CdTe thin film solar ceils, the plasma etching process used in No. B7 sample is suitable for the post treatment of CdTe thin film solar cells. The conversion efficiency （10. 99%） of CdTe thin film solar cells with complex back contact layer and post treated by plasma etching is higher than the one （10.26%） by bromine and methanol mixture corrosion. It can be seen that the dry plasma etching used for CdTe thin film solar cells is more suitable for industrial production than the wet etching.