Thermodynamic Effects Of Interaction Between 1070nm CW Laser And Triple-junction GaAs Solar Cells

The triple junction GaAs solar cell is widely used in various spacecrafts as a main power source because of its high efficiency,radiation resistance,long transmission distance and long working life.On the one hand,lasers with suitable wavelengths can power solar cells;on the other hand,higher power lasers can be used as weapons to effectively destroy solar cells in space.Therefore,it is of great significance to study the thermal effects of laser interaction with solar cells.In this paper,the basic theory of laser-semiconductor interaction and the structure and working principle of three-junction GaAs solar cells are briefly introduced.Then,based on the thermoelastic theory,the finite element software COMSOL is used to establish the corresponding model,and the lasers with different power densities are numerically calculated.The temperature field and thermal stress field of the battery are compared.The numerical calculation results of the temperature field are compared with the experimental results in the literature.The variation trend of thermal stress in all directions of the battery is analyzed,and the failure of the battery and the equivalent stress at the center of the surface of bottom battery are obtained.and the effects of laser irradiation radius,surface reflectance and thermal convection coefficient on battery temperature and thermal stress are discussed.In addition,the grid line projection method is used to measure the deformation of the surface of the battery under the action of higher power laser.It is found that there is a circle of depression in the laser irradiation area,and the depth of the concave portion is 25 ?m.Then the plastic deformation value is introduced to calculate the deformation of the battery surface.The numerical calculation results are compared with the experimental results,and the causes of the error are analyzed.Finally,the different damage modes of continuous laser to battery and the damage threshold under different damage modes are summarized.The research results in this paper can provide a reference for the study of thermal and mechanical directions for the further study of the interaction between laser and semiconductor laser and solar cells.