Multi-physics Coupling Analysis Of InP/InGaAs Photodetectors

InP/InGaAs PIN high-speed photodetector is a key device in the optical fiber communication system,and also the core component of the transmitting and receiving end of the 5G scale online game.With the development requirements of high communication speed and strong communication quality,higher research is also required for the research of high-performance photodetectors.The high-speed performance of the PIN photodetector is affected by many factors such as temperature field and electric field.The interaction of these physical fields is not independent.They have strong or weak coupling problems.If the conventional method is used for analysis,the process is not only complicated but also complicated.It is also inconvenient to quantitatively analyze the working conditions of the device under the action of real multiphysics.In this paper,by establishing an equivalent model of the PIN photodetector,the modeling and simulation work of multiphysics coupling is carried out,and from the experimental demonstration and simulation analysis Two ways to study the methods to improve the high-speed performance of InP/InGaAs PIN photodetectors.The specific work done in this article is as follows:1.Analyze the working principle and structural characteristics of InP/InGaAs PIN high-speed photodetector.A number of parameters that characterize its working performance,such as dark current,response speed,internal quantum efficiency,and responsiveness,are theoretically analyzed,and the work of obtaining the equivalent circuit model of the device through equivalent transformation is emphasized to provide subsequent research Sufficient theoretical basis.2.InP/InGaAs PIN photodetector was modeled and simulated by multi-physics coupling.Based on the established simulation model,the performance of the model before and after Zn diffusion was quantitatively analyzed and compared by finite element analysis.Mainly include: the relationship between energy band and temperature,I-V characteristics,electric field strength,the relationship between photocurrent and incident wavelength and temperature,etc.Through comparison analysis with the calculation results,the 3d B bandwidth of the PIN photodetector optimized without Zn diffusion has increased by 49.7%(from 7.88 GHz to 11.8GHz)under 20 V reverse bias voltage and 100? load resistance.The high degree of agreement between simulation and calculation further proves the effectiveness of multiphysics coupling and the rationality of the photodetector simulation model.3.Based on the modeling and analysis results of InP/InGaAs PIN photodetector multi-physics coupling modeling,the epitaxial structure growth of the device is optimized,and the preparation of the device and related experimental tests are guided.The epitaxial growth of the InP/InGaAs photodetector was completed and the device was prepared by epitaxial structure design.Secondary ion mass spectrometry(SIMS)analysis showed that the Zn diffusion was suppressed after reducing the P-type In P growth temperature(from 873 K to 673K).Before the epitaxial sample,the dark current of the optimized epitaxial sample is much reduced,and the 3d B bandwidth test after adding a 20 V reverse bias voltage to the device shows that the optimized 3d B bandwidth is 11.6 GHz,which is an increase from the optimized 3d B bandwidth 8.1 GHz 43.2%,the comparison of simulation results also shows that the multiphysics coupling simulation has high credibility in guiding the optimization of device epitaxial structure growth.