Study On Interconnect Technology And Reliability Of Optical Fiber Connectors

In this paper,the interconnection process and thermal fatigue reliability of optical fiber connection are studied.In view of the problem that fiber joints are prone to produce fatigue cracks and gas leakage when they are used in the environment of±100?alternating for a long time.Based on the suitable solder for the welding of this connection joint,the related welding process,welding quality and interface reaction was explored.The thermal fatigue reliability of the connection joint was evaluated combined with the finite element simulation method,and the size of optical fiber connector was optimized.The results show that using AuSn20 eutectic solder to seal the optical fiber connector,when the maximum temperature is 330?and the heating time is 4 minutes,the connector has good sealing performance,and the leakage rate is?1×10^-10Pa·m³/s;Both the reflow process and the external environment can affect the interface organization and change the reliability of the joint.When SnPb37 eutectic solder is used as the interconnect solder,a large amount of brittle needle-like compound AuSn4 is generated near the interface between the Kovar tube and Kovar base,which easily causes fatigue failure of the solder joint.Anand viscoplastic constitutive equation was used to describe the thermodynamic behavior of AuSn20,SnPb90 and SnPb37 solders under thermal cyclic loading The stress and strain fields of three solder models under thermal cyclic loading were simulated using ANSYS.It is found that the key location for fatigue failure of the weld seam?is the sharp corner area of the solder layer edge;the key location for failure of the weld seam?is near the edge of the solder-fiber connection interface.At the end of the thermal cycle,the high stress areas in the lead-based solder connections are in the fiber.Using the coffin-manson equation to evaluate the fatigue life of these three models,it is found that the ideal life of AuSn20 solder can reach 49.5years,while the service life of the other two solder joints was only about 1 year.At high temperature,the viscoplastic characteristics of lead-based solders are more obvious,and the cumulative inelastic strain value in a single cycle is greater.Under the same service conditions,the thermal fatigue life of AuSn20 solder is much higher than that of SnPb90 and SnPb37solders,which is more suitable for sealing welding of optical fiber connectors.The size of the AuSn20 solder model joint was optimized,and the results show that the optimal size of the fiber connector is D=1.49mm,d=1.39mm,d₁=340?m,and d₂=125?m.