论文部分内容阅读
对电子束蒸发方式镀制的HfO2/SiO2反射膜采用大口径激光进行辐照,采用激光量热计测量了激光辐射前后的弱吸收值。实验发现HfO2/SiO2反射膜在分别采用1 064nm和532nm的激光辐照前后薄膜吸收分别从5.4%和1.7%降低到1.4和1.2%。采用聚焦离子束技术分析了激光辐照后薄膜的损伤形态并探究了损伤原因,发现:薄膜在激光辐照下存在节瘤的地方容易出现薄膜损伤,具体表现为熔融、部分喷发、完全脱落3种形态,节瘤缺陷种子来源的差异是导致其损伤机理也存在着巨大差异的主要原因。同时这些节瘤缺陷种子来源也影响着激光预处理作用效果,激光预处理技术对于祛除位于基底上种子形成的节瘤是有效的,原因是激光辐射过后该节瘤进行了预喷发而不会对后续激光产生影响;而激光预处理技术对位于膜层中间的可能是镀膜过程中材料飞溅引起的缺陷是无效的,需要通过飞秒激光手段对该类节瘤进行祛除。
The HfO2 / SiO2 reflective film coated by E-beam evaporation method was irradiated by a large-diameter laser, and the weak absorption before and after the laser radiation was measured by a laser calorimeter. The experimental results show that the absorption of HfO2 / SiO2 film decreases from 5.4% and 1.7% to 1.4 and 1.2% before and after laser irradiation with 1 064nm and 532nm, respectively. Focused ion beam technique was used to analyze the damage morphology of the thin film after laser irradiation and to explore the cause of the damage. It was found that thin films were easy to be damaged in the presence of nodules under laser irradiation. The thin films were characterized by melting, partial eruption and complete ablation The differences of seed sources between species and knot defects are the main causes of the huge differences in the damage mechanisms. At the same time, the origin of these knot defects also affects the laser pretreatment effect. Laser pretreatment technique is effective in removing the nodules formed on the seeds of the substrate due to pre-eruption of the knot without laser irradiation Follow-up laser impact; and laser pretreatment technology is located in the middle of the film may be coated during the material splash caused the defect is ineffective, you need to femtosecond laser means to get rid of such nodules.