Study On Key Technologies Of 4×100Gb/s Optical Transceiver Module Integration

In recent years,5G,data center and other technologies have developed rapidly,and their requirements for interconnection bandwidth are higher and higher.Therefore,higher requirements are put forward for the transmission rate of optical transceiver module,which is a key part of the bearer network.At present,for improving the transmission rate of optical transceiver module,most manufacturers of optical transceiver module adopt the method of increasing the number of channels and spatial density.However,due to the volume of optical transceiver module and the signal integrity risks such as crosstalk brought by this method,the development potential of this method is difficult to meet the growth rate of interconnection bandwidth demand.In contrast,improving the bandwidth and transmission rate of a single channel not only obtains higher overall transmission rate,but also obtains more design margin,which has great potential and development prospects.Therefore,in order to ensure and improve the single channel transmission rate of 4×100Gb/s optical transceiver module,this thesis introduces and analyzes the key technologies of optical transceiver module at the level of integrated packaging from the two aspects of high-performance device integration and signal integrity of packaging,based on the theory of signal integrity,Through theoretical analysis and simulation experiments,the design rules of integrated packaging of high transmission rate optical transceiver module are studied.According to these rules,an experimental board in the form of chip on board(COB)is designed and manufactured to verify the effectiveness of key technologies.The main work of this thesis is as follows:(1)The characteristics of thin film lithium niobate Mach Zehnder modulator and its potential in improving the transmission rate of optical transceiver module are introduced.Based on the electromagnetic field theory,the propagation characteristics of electromagnetic wave in lithium niobate crystal and the linear electro-optic effect of lithium niobate crystal are derived.On this basis,the working characteristic equation of thin film lithium niobate modulator is derived.The advantages of thin film lithium niobate modulator compared with traditional silicon optical modulator and bulk lithium niobate modulator and its new requirements for integrated packaging are expounded.(2)The main theories,tools and methods of signal integrity analysis at the level of integrated packaging are introduced.The key factors affecting signal integrity at the level of integrated packaging,such as impedance continuity,high frequency effect and so on,are analyzed in time domain and frequency domain.Through numerical simulation and theoretical analysis,the transmission line,lamination,bonding and welding transition section on COB are optimized for high-frequency signals above 50 GHz.(3)Based on the signal integrity design rules,the test board is designed and manufactured,and the experiment and analysis are carried out to study key technologies of 4×100Gb/s optical transceiver module integration.The test shows that the COB designed based on signal integrity is encapsulated in the bandwidth of 50 GHz,the insertion loss is less than 3d B,the return loss is greater than 10 d B,the eye width is greater than 0.22 UI,and the eye height is greater than0.03.The transmission rate of single channel is more than 100Gb/s through the PAM4(4-level Pulse Amplitude Modulation)method,and can meet the requirements of 4×100Gb/s transmission rate.