靶材吸收率变化与烧蚀过程熔融前靶材温度分布

讨论了脉冲激光沉积法中烧蚀阶段熔融前靶材吸收率的变化对于其温度分布的影响. 给出了靶材吸收率随时间的变化规律，并在此基础上，利用较为符合实际的高斯分布表示脉冲激光输入能量密度，建立了相应的热传导方程. 结合适当的边界条件，利用有限差分法，以硅靶材和钨靶材为例，给出了靶材熔融前温度分布随时间和深度变化的演化分布规律，同时对相关过程的物理图像进行详细的讨论.对于吸收率的变化与脉冲激光能量密度的分布对于相应过程的影响，进行了分析讨论. 结果表明，在脉冲激光中间的持续过程中，忽略靶材吸收率的变化对于最终的模拟结果有重要影响，从而导致理论结果与实验数据有较大差异. 关键词： 脉冲激光沉积 吸收率 有限差分 温度演化

Variation of the target absorptance and target temperature distribution before melting in the pulsed laser ablation process

We have discussed the effect of the variation of target absorptance on the temperature distribution of the target before melting. The relationship of the target absoptance with time is derived. Based on this relationship and the actual shape of incident energy density which is a Gauss distribution, the relevant heat flow equation is set up. By using the finite difference method, heat flow equation under an appropriate boundary condition is solved. We have obtained the temperature distribution as function of time and location. At the same time, we have also discussed the physical picture of a relevant process in detail. Finally, we have studied the effect of the variation of absorptance and the distribution of incident energy density on the relevant process. The result shows that during the pulsed laser process, the variation of target absorptance has an important effect on the final simulation result. If this variation is neglected, a remarkable difference can be found between theoretical results and experimental data.