Bandgap Engineering of Bilayer Ge/CdS Thin Films via Interlayer Diffusion under Different Annealing Temperatures

Figure 4

(a-d) AFM images of the annealed films. The samples annealed at the different temperatures show the increased roughness with the annealing temperature. The sample annealed at 400°C shows the associated oxides which can be confirmed by XPS.

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