Drift-diffusion numerical simulation of UTC photodiodes for on-chip optical interconnections

A^IIIB^V laser-modulator is an advanced optoelectronic device offering new possibilities in the field of on-chip optical interconnecting. To realize the laser-modulator-based interconnections, high-performance integrated photodetectors are required. In this paper, we researched uni-travelling-carrier photodiodes (UTC-PDs). We proposed the extended driftdiffusion model taking into account the effects of carrier drift velocity saturation and electron inter-valley transition. For the implementation of the model, we developed the finite difference numerical simulation technique and dedicated software. These aids were applied for the simulation of InP/InGaAs UTC-PD. According to the simulation results, the device response time is about 3 ps. Thus, it is reasonable to consider the methods of UTC-PD performance improvement. (paper)