A 4×52 Gbps PAM4 WDM Transmitter with Silicon Photonics Microring Modulator

Optical transmitter is the carrier to realize optic communication. It is important to study the package design of high data rates optical transmitter and solve the engineering problems in the application of optical transmitter for optic communication. MRM-based wavelength division multiplexing (WDM) transmitter has become a hot topic because of the features of microring modulator (MRM). The development trend of MRM-based WDM transmitter is toward high density and high single-channel rate. In this paper, a 12-channel silicon photonics MRM-based WDM transmitter controlled by three CMOS drivers is designed. In addition, to increase the temperature stability of the MRM-based transmitter, a thermoelectric cooler (TEC) is introduced. Besides, high temperature co-fired ceramic (HTCC) is adopted in this study for hermetic encapsulation of TEC to ensure the high reliability of the TEC which could be impacted by the condensed water drop. After the carefully design and optimization, the WDM transmitter is fabricated. And four channels controlled by one of the drivers are measured. The results show that the 4-channel transmitter at 52 Gbps/ch PAM4 signals is obtained. And 12×52 Gbps PAM-4 signals transmission through a transmitter is potential.