钝化处理在消除多晶Si薄膜缺陷中的应用

介绍了消除多晶Si太阳电池薄膜中缺陷的各种钝化方法,主要包括利用氢等离子体、SiNx∶H薄膜、Se单原子层、二元(Al2O3)x(TiO2)1-x合金、SiO2/Si/SiO2量子阱以及湿法化学反应所实现的对缺陷进行有效钝化处理等方法;基于本研究领域的最新进展,对各种方法的优缺点进行了分析归纳。指出H钝化可获得较好的钝化效果,但在后续热处理过程中,Si—H键会由于温度过高而断裂,致使氢离子离开表面而使钝化效果变差;SiNx∶H氮化物薄膜可以有效阻挡氢的外扩散,保持钝化效果的稳定性,还可以起到对光的减反射作用。研制具有较低的光反射率、非平衡载流子的高收集效率以及低界面态密度的薄膜和提高薄膜的机械强度是当前科学工作者应该关注的课题。

Passivated Treatment and Its Application of Removing Defects in Polycrystalline Silicon Thin Film

Some passivated methods of removing the defects in polycrystalline silicon solar cell film were introduced,such as the passivation achieved by hydrogen plasma,SiNx∶H film,Se monolayer,binary alloys(Al2O3)x(TiO2)1-x,SiO2/Si/SiO2 quantum wells,and wet-chemistry.Based on the newest progress of the subject,relative merits of these methods are analyzed and concluded.The results indicate that,although the better effect of the hydrogen passivation is achieved,Si—H bond cracks in the following processes of treatment because of the high temperature,which causes the ion hydrogen to leave the surface and brings the bad effect of the passivation.The SiNx∶H film can effectively prevent the external diffusion,retain the stability of the passivation effect,and reduce the reflection of light.It indicates that the fabricating of the films with low light reflectivity,high collection efficiency for non-equilibrium carriers,and low interface state density and enhancing the mechanical strength of film are the subjects to which scientists should pay attention.