Figure 7
From: Multiple electron transporting layers and their excellent properties based on organic solar cell

AFM topographic image of ZnO (AZO) Nanostructures film, (1.5 μm × 1.5 μm) (i) ZnO, 3.44 nm; (ii) AZO-10, 3.8 nm; (iii) ZnO/AZO-10, 3.63 nm.