Nanopatterned silicon emitters of a solar cell fabricated by anodic aluminum oxide masks

We investigated the nanopattern transferring process by a template of anodic aluminum oxide and the formation of a nanoporous aluminum oxide layer on a Si solar cell by the anodization process of Al thin films. The anodization process provided a template to transfer the nanopattern onto the Si surface. The small-sized nanoporous alumina template was attached to be covered on the textured surface and played the role of etching mask in the F-based dry etching process. Furthermore, we deposited an Al thin film onto the Si surface and the subsequent anodization process was performed. The alumina formulated on the deposited Al thin film did not show the array of nanoporous structure and no nanopatterns were transferred onto the surface. The large-areal alumina deposited on the Si surface showed enhanced photo-absorption in the ultraviolet spectral region of 243 nm, but increased the photo-reflectance in the visible and infrared spectral regions when compared to the Si-bare sample.