Performance Evolutions of Carrier Depletion Silicon Optical Modulators: From p-n to p-i-p-i-n Diodes

The performance evolution of p-n, p-i-n, and p-i-p-i-n optical modulators based on free-carrier concentration variation is studied. Main figures of merit are recalled for such devices and used to compare one structure to another. The modulation efficiency, optical loss, and -3 dB cutoff frequency are thus optimized for each sort of studied junction. General performance results are presented and discussed at the end.