Fig. 1
Schematic representation of photodetection. The process involves exciton generation, separation, drift, and charge collection, facilitated by a built-in electric field. The electric field is generated either by the built-in potential of the junction or an external bias supply, enabling efficient photocarrier transport and extraction. Here, ECB, EVB, and EF represent the conduction band, valence band, and the Fermi level energy, respectively.
