Figure 7.

Energy band diagrams of the GNWs/Si photodetectors (a) without a HfO₂ interfacial layer, (b) with a thin HfO₂ interfacial layer, and (c) with a thick HfO₂ interfacial layer under illumination conditions. Here ${\phi }_{SBH}$ represents the Schottky barrier height; ΔE is the difference between GNWs Fermi level and quasi-Fermi energy level for holes in Si; E_c and E_v are the energy levels of conduction band and valence band for Si, respectively; E_fn and E_fp are quasi-Fermi energy levels of electrons and holes for Si, respectively.