Fig. 3
From: Modelling and optimization of Ge/GaAs uni-travelling carrier photodiodes
Band diagram and Electric Field Diagram for diameter with 5 µm Ge/GaAs UTC-PD. (a) The band diagram of the Ge/GaAs UTC-PD illustrates the conduction band (black) and valence band (red) energies as a function of depth. (b) The electric field diagram shows the electric field intensity as a function of depth within the Ge/GaAs UTC-PD at various biases (0 V, -1 V, -2 V). Both diagrams demonstrate the various layers, including the cathode contact, collection layer, spacer layer, cliff layer, absorption layer, diffusion barrier, and anode contact.
