激光预处理对HfO_2薄膜损伤特性的影响  

Influence of Laser Conditioning on the Damage Properties of HfO_2 Thin Film

作　　者：杨利红[1] 王涛[1] 苏俊宏[1] 韩锦涛[1] 

机构地区：[1]西安工业大学光电工程学院,陕西西安710021

出　　处：《光学学报》2013年第12期336-342,共7页Acta Optica Sinica

基　　金：国家自然科学基金(61378050);陕西省教育厅专项科研计划项目(12JK0996);陕西省科学技术研究发展计划项目(2011KW-05)

摘　　要：研究了在1-on-1情况下,采用不同激光能量对HfO2薄膜进行预处理后,薄膜的光学特性、损伤阈值以及损伤形貌变化的机理。实验采用阈值能量的10%、30%、50%、70%对薄膜进行1-on-1预处理,经过预处理后的薄膜表面粗糙度平均从2.62nm降低到2.41nm。随着能量阶的提升,激光预处理后薄膜在1064nm处的透射率与预处理前相比均有所增大。激光损伤阈值先增后降,30%能量预处理的薄膜损伤阈值最高,达到了26.86J/cm2,增幅为56%。对比预处理前后的损伤形貌可知,30%能量预处理后薄膜在140mJ能量下,损伤深度由预处理前的98nm减小到了30nm,损伤斑个数由预处理前的5个减少到了预处理后的1个。实验结果表明:膜内杂质缺陷是导致HfO2薄膜阈值降低的因素,低能量的激光预处理薄膜有消除杂质缺陷,平整、固化膜层的作用,因而可以有效地提高薄膜的激光损伤阈值。The effects of different laser fluences on the optical properties of HfO2 thin films mainly including damage threshold and damage morphology, are studied under 1-on-1 condition. In experiment, the energies of 10%, 30%, 50% and 70% of the threshold energy are used to condition the HfO2 films in 1-on-1 mode. After conditioning, the surface roughness decreases from 2.62 nm to 2.41 nm. With the energy increasing, the transmittance at 1064 nm is enlarged with conditioning. The damage threshold is increased firstly, and then decreases. When the energy is 30% of the threshold energy, the damage threshold reaches the maximum value of 26.86 J/cm2 and increases by 56%. Comparing the damage morphology between conditioning and without conditioning, after the film is conditioned with 30% of the threshold energy, the damage depth under 140 mJ laser irradiation decreases from 98 nm without conditioning to 30 nm and the damage spot number decreases from 5 to 1. The experiment result shows that inclusions are the main factors of threshold decrease and conditioning with low laser fluences has the effect of decreasing the defects and solidifying the film, thus it can improve the laser-damaged threshold of films.

关 键 词：薄膜 激光预处理 杂质 1-on-1 粗糙度 损伤斑 

分 类 号：O484[理学—固体物理]