The impact of the anodization process of anodic aluminum oxide fabrication and post-deposition anneal on effective carrier lifetime of Si nanowires are reported. The anodization process with suitable switched-off anodization currents results in enhanced effective carrier lifetime of Si nanowires that are significantly higher than that of early and late switched -off anodization currents. Furthermore, the anodic aluminum oxide template exhibits an efficient passivation upon post-deposition anneal, yielding a maximum value of 228 In under thermal treatment at 650 degrees C. First fabrication of Si nanowire solar cell embedded with anodic aluminum oxide template was carried out. Through post-deposition anneal prior to the fabrication of Si nanowire solar cells, the performance of Si nanowire solar cells was significantly improved. This established the impact of thermal treatment on opto-electronic characteristics of Si nanowires embedded with anodic aluminum oxide.