为了研究了激光与CCD传感器的作用过程及损伤机理, 采用有限元分析的方法, 对波长1.06μm的连续激光辐照行间转移型面阵CCD进行了理论分析和仿真研究。以基底Si表面激光辐照区域为热源建立热力耦合模型, 模拟得出了CCD的温度分布和热应力分布。通过对比分析其组成材料的温度损伤和应力损伤所发生的时间, 发现应力损伤先于温度损伤。结果表明, 作为固定边界和自由边界的交汇处, 基底Si下表面边缘处热应力于激光作用0.1s时最先超过破坏阈值120MPa, 发生应力破坏;Si材料产生由下表面边缘向中心的滑移, 基底逐步脱离固定;激光作用0.3s时, 遮光Al膜与SiO2膜层也因热应力超过两种材料的附着力100MPa, 而产生沿径向由内向外的Al膜层剥落的应力破坏行为, 这种行为将加快基底Si材料的滑移, 最终致使整个CCD因脱离工作位置而失效。该研究成果为CCD传感器的激光损伤及防护提供了理论依据。

In order to study interaction process and damage mechanism between laser and CCD sensors, an interline transfer surface array CCD irradiated by 1.06μm CW laser was analyzed and simulated by means of finite element analysis. Thermal coupling model was established by using laser irradiation area of substrate Si surface as heat source. The temperature distribution and thermal stress distribution of CCD were simulated. By comparing and analyzing temperature damage and stress damage of the components, it was found that stress damage was prior to temperature damage. The results show that as the convergence of the fixed boundary and the free boundary, the thermal stress at the edge of the lower surface of the base Si is the first to exceed the damage threshold of 120MPa at the time of laser action of 0.1s, and stress failure occurs. Si material slips from the lower surface edge to the center, and the substrate is gradually out of fix. At the time of laser action of 0.3s, stress failure occurs to Al film and SiO2 film and Al film strips radically from the inside to the outside due to thermal stress over the adhesion strength of 100MPa, finally the CCD is out of work position and fails. The research achievements provide theoretical basis for laser damage and protection of CCD sensors.