The Research On Thermal Stress Of Silicon-Based Pin Detector Irradiated By Millisecond-Pulse Laser

The silicon-based PIN detector is widely applied in many fields, such as medicine, industry, etc. When silicon-based PIN detector receives the high power laser, it is vulnerable to be interfered and damaged by high power laser. Thus it is significant to study the damage mechanism of silicon-based PIN detector by laser. In formal research, the damage of photoelectric detectors is more about CW laser and short pulse laser. For silicon-based photoelectric detector irradiated by the long pulse laser, it mainly focused on simulation and considered silicon-based PIN detector as a certain material. It has not been reported about the research of thermal stress damage of PIN multi-layer materials by milliseconds long pulse laser.Based on the heat transfer theory thermal and elasto-plastic constitutive theory, using the equivalent specific heat method to deal with the phase change latent heat, considering multiple-heat-source, especially the reflection influence of bottom-aluminum-electrode, as well as considering the effect of each layer material parameters of the nonlinear effect, a2-D simulation model was built by means of the finite element simulation software of COMSOL Multiphysics. As a result, the material surface and each layer of internal changes of the transient distribution and evolvement of thermal and stress with the space and time was obtained. Moreover, the experiments completed by choosing the appropriate parameters of pulse laser parameters irradiating the silicon-based PIN photodiode, and monitoring the surface temperature of the silicon-based PIN photodiode at the same time, until the silicon PIN photodiode complete failure. Comparing experimental with the simulation results, the reliability and accuracy could be verified. Furthermore, the failure causes of the silicon-based PIN detector have been explored successfully.The results of the laser damage and damage resistance of silicon-based PIN detector of further research work plays an important significance.