Nam Sang-Hun, Choi Jin-Woo, Cho Sang-Jin, Kimt Keun Soo, Boo Jin-Hyo
Department of Chemistry and Institute of Basic Science, Sungkyunkwan University, Suwon 440-746, Korea.
J Nanosci Nanotechnol. 2011 Aug;11(8):7315-8. doi: 10.1166/jnn.2011.4813.
Recently anti-reflective films (AR) have been intensely studied. Particularly for textured silicon solar cells, the AR films can further reduce the reflection of the incident light through trapping the incident light into the cells. In this work, TiO2 anti-reflection films have been grown on the textured Si (100) substrate which is processed in two steps, and the films are deposited using metal-organic chemical vapor deposition (MOCVD) with a precursor of titanium tetra-isopropoxide (TTIP). The effect of the substrate texture and the growth conditions of TiO2 films on the reflectance has been investigated. Pyramid size of textured silicon had approximately 2-9 microm. A well-textured silicon surface can lower the reflectance to 10%. For more reduced reflection, TiO2 anti-reflection films on the textured silicon were deposited at 600 degrees C using titanium tetra-isopropoxide (TTIP) as a precursor by metal-organic chemical vapor deposition (MOCVD), and the deposited TiO2 layers were then treated by annealing for 2 h in air at 600 and 1000 degrees C, respectively. In this process, the treated samples by annealing showed anatase and rutile phases, respectively. The thickness of TiO2 films was about 75 +/- 5 nm. The reflectance at specific wavelength can be reduced to 3% in optimum layer.
近年来，减反射膜（AR）受到了广泛研究。特别是对于纹理化硅太阳能电池，减反射膜可以通过将入射光捕获到电池中进一步降低入射光的反射。在这项工作中，TiO₂减反射膜生长在经过两步处理的纹理化Si（100）衬底上，并且使用四异丙醇钛（TTIP）作为前驱体通过金属有机化学气相沉积（MOCVD）来沉积这些膜。研究了衬底纹理和TiO₂膜生长条件对反射率的影响。纹理化硅的金字塔尺寸约为2 - 9微米。良好纹理化的硅表面可将反射率降低至10%。为了进一步降低反射率，通过金属有机化学气相沉积（MOCVD），以四异丙醇钛（TTIP）作为前驱体，在600℃下在纹理化硅上沉积TiO₂减反射膜，然后分别在600℃和1000℃的空气中对沉积的TiO₂层进行2小时的退火处理。在此过程中，经过退火处理的样品分别呈现出锐钛矿相和金红石相。TiO₂膜的厚度约为75±5纳米。在最佳层中，特定波长下的反射率可降低至3%。
