Study on the mechanism of continuous laser damage to silicon-based CCD imaging structure

In order to solve the physical field quantity that characterizes the laser irradiation effect by the transient temperature , using the finite element-finite difference numerical hybrid algorithm, the absorption coefficient, specific heat capacity, thermal conductivity, density and other dynamic target characteristic parameters that change with temperature are introduced. Based on the melting process of continuous laser action target obtained by equivalent specific heat capacity method, the simulation model of the temperature of the target irradiation process with the laser characteristics such as power and action time is established. For a silicon-based CCD target with a composite structure, a two-dimensional model is established during the calculation of the silicon-based CCD, and the thin-layer grid of the composite structure is encrypted. The maximum temperature of the upper surface center point of the aluminum layer of the silicon-based CCD with the action time under the continuous laser characteristic power is simulated. The maximum temperature of the center point on the upper surface of the silicon-based CCD varies with the power under different continuous laser characteristics. And the relationship between the temperature of the upper surface of the silicon-based CCD and the power under the fixed continuous laser characteristic time is simulated.