Design of Novel InP/InGaAs Photodetectors With NiO Transparent p-Region and Electrode

In this study, we report a new type of InGaAs/InP photodetector (PD) with nickel oxide (NiO) transparent p-region and electrode. By applying the NiO film, the device does not require the highly doped p-contact layer and the opaque p-contact metal electrode such as the traditional p-i-n PD. The epitaxial layer of the PD is simplified. Meanwhile, the optical power loss caused by the additional absorption in the highly doped p-contact layer can be avoided. With the fully covered transparent p-contact electrode, the PD can be illuminated from the p-side at the same time. The numerical simulation results show that the new structure can improve the 3-dB bandwidth and the RF output power of the PD.