相变域硅薄膜材料的光稳定性

Stability of mixed phase silicon thin film material under light soaking

采用RF-PECVD技术,通过改变反应气体的硅烷浓度制备了一系列不同晶化率不掺杂的硅薄膜材料,研究了工艺变化对材料结构的影响及材料光电特性同微结构的关系.随后进行了光衰退试验,在分析光照前后光电特性变化规律的基础上,认为材料中的非晶成分是导致材料光电特性衰退的主要原因.在靠近过渡区非晶一侧的硅材料比普通非晶硅稳定,衰退率较少;高晶化率微晶硅材料性能稳定,基本不存在光衰退;在靠近过渡区微晶一侧的硅材料虽然不是完全不衰退,但相比高晶化率硅材料来说更适合制备高效微晶硅电池.

Silicon thin films material with different crystalline ratio （ Xc ） have been deposited with varying silane content of source gases in the PECVD process. We have researched how hydrogen content affects the material and the relationship between micro- structure and optoelectronic properties. Light soaking experiment was then performed. By comparing the changes in the properties before and after irradiation, we conclude that the amorphous region is responsible to the degradation of the photoelectronic property. The mixed phase amorphous silicon degrades less and is more stable than component the common amorphous silicon. The highly crystallized silicon is stable against light soaking. The microcrystalline silicon near the threshold is not so stable as the highly crystallized one, but its optoelectronic property is more suitable than the others for making microcrystalline silicon solar cells.