中频磁控溅射法制备掺氢氮化硅减反/钝化复合功能薄膜的研究

Silicon nitride thin films with passivation and anti-reflection properties prepared by mid-frequency magnetron sputtering

使用中频磁控溅射法制备了具有光学减反射与电学钝化的复合功能的氮化硅（SiNx）薄膜,并对其结构和性能进行了综合研究。结果表明：在常规制绒硅片上沉积的两种不同折射率的单层SiNx减反膜表现出优异的光学性能,其在300-1 100 nm波段的平均反射率由镀膜前的14.86%下降到镀膜后的5.50%和6.58%;若采用多层的氮化硅（m-SiNx）＋氮氧化硅（SiOx Ny）薄膜作为减反层,则其平均反射率进一步下降到4.03%。同时,优化工艺制备得到的掺氢氮化硅（Si Nx∶H）薄膜,表现出良好的电学钝化特性。试验中分别制备了两种复合结构的薄膜,即SiNx∶H（厚度15 nm）＋m-SiNx＋SiOxNy与SiNx∶H（厚度30 nm）＋m-SiNx＋SiOxNy复合薄膜,其平均反射率分别为5.88%和5.43%;把这两种薄膜用于晶体硅太阳电池上,其开路电压则都达到了575 m V,表现出良好的性能。

Silicon nitride （SiNx ） film with excellent quality in both passivation and anti-reflection was deposited by mid-frequency （MF） magnetron sputtering process. The structure, optical property and other relevant performances of the thin films were investigated. The results show that, in the range of 300 - 1 100 nm, the average reflection of the textured silicon decreased from 14. 86% to 5.50% and 6. 58% respectively by applying two different single layer of SiNx films. The average reflection further decreased to a value of 4. 03% when a muhilayer of SiNx ＋ SiOxNy film was applied. Meanwhile, a hydrogen doped silicon nitride （ SiNx： H） film was prepared for the passivation purpose. Based on the parameter optimization, two series of the composite films including SiNx： H （15 nm in thickness） ＋ SiNx ＋ SiOxNy and SiNx： H （30 nm in thickness） ＋ SiNx ＋ SiOxNy were prepared. The average reflections of the composite films reached at 5.88% and 5.43%, respectively. The films were then applied to the crystalline silicon solar cells, an open circuit voltage of 575 mV were achieved, indicating the composite film with a good passivation property.