The optimization of textured boron-doped conductive zinc oxide (ZnO:B) films deposited by metal organic chemical vapor deposition (MOCVD) for hydrogenated microcrystalline silicon (µc-Si:H) solar cells was performed. We found that the argon (Ar) plasma treatment of a textured ZnO:B substrate is effective in improving the open-circuit voltage and fill factor of µc-Si:H solar cells. We proposed (tan θ)/λ2 as an evaluation factor and found that there is a clear correlation between the (tan θ)/λ2 of textured ZnO:B films and the open-circuit voltage of µc-Si:H solar cells. Moreover, the effect of the surface morphology of a textured ZnO:B substrate on the growth of intrinsic hydrogenated amorphous silicon (i-a-Si:H) top layers was examined to obtain the optimum conditions for preparing a-Si:H/µc-Si:H tandem solar cells. We confirmed that our proposed evaluation factor (tan θ)/λ2 could be used to obtain the surface morphology of i-a-Si:H top layers that are appropriate for µc-Si:H bottom-cell deposition.