Analysis of germanium-doped silicon vertical PN junction optical phase shifter

In this paper, the performance of a germanium-doped silicon optical phase shifter with vertical PN junction has been investigated. The proposed phase shifter is simulated using a process simulation tool, and 2D carrier distribution has been used to calculate the phase shifter performance metrics. The designed phase shifter is integrated into a Mach-Zehnder interferometer structure, and the transfer characteristics are plotted. The proposed phase shifter has a phase shift of ~141°/mm, V_πL_π of ~0.64 V · cm, insertion loss of ~1.23 dB, and 3 dB bandwidth of ~37 GHz at 5 V reverse bias.