权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Rltraprecision Machinig of Optical Materials for Deep Ultra Violet Lasers of High Brightness and Improvement of Optical Performancs

高亮度深紫外激光器光学材料的超精密加工及光学性能的提高

基本信息

批准号：
11450063
负责人：
OHNISHI Naoyuki
金额：
$ 9.47万
依托单位：
CHUBU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2001
项目状态：
已结题

项目摘要

Deep Ultra Violet (DUV) lasers of high brightness are expected as a light source for the next generation micro lithography, laser micro processing due to photo-chemical reaction and laser fusion. However, there are serious problems such as the limitation of optical materials to be transmitted, lack of experience of machining on the optical materials in high precision and laser induced damages of the materials. This research work is intended to propose the flat optical components for DUV lasers of high brightness in high precision, high transmittance, high Laser Induced Damage Threshold (LIDT) and high reliability.The (111) surfaces of high purity calcium fluoride (CaF_2) single crystals for DUV were polished and 0.16nm rms in surface roughness was obtained on the float polished surface, measured with an atomic force microscope (AFM). From the observation with a high voltage transmission electron microscope (HVTEM), it was clarified that the float polished surface shows perfect (111) lattice and small atomic steps and there are no damage on the subsurface. We obtained a fourth harmonic laser of 266nm in wavelength by using nonlinear crystals of KDP and CLBO from Nd:YAG lasers. From the irradiation of the laser on the GaF_2 crystals, LIDT was measured. The LIIDT numbers are different among the CaF_2 crystals in various benders, surface finish and laser irradiation number.

由于光化学反应和激光聚变，高亮度的深紫外（DUV）激光器被期望作为下一代微光刻、激光微加工的光源。然而，目前光学材料的加工存在着一些严重的问题，如光学材料本身的局限性、缺乏高精度加工的经验以及材料的激光损伤等。为研制高亮度、高精度、高透过率、高激光损伤阈值（LIDT）和高可靠性的深紫外（DUV）激光器用平板光学元件，对高纯氟化钙（CaF_2）单晶的（111）面进行了抛光，抛光后的表面粗糙度达到0.16nm rms。用原子力显微镜（AFM）测量。从用高压透射电子显微镜（HVTEM）的观察中，澄清了浮动抛光表面显示出完美的（111）晶格和小的原子台阶，并且在次表面上没有损伤。本文用KDP和CLBO非线性晶体从Nd：YAG激光器中获得了266nm的四倍频激光。用激光照射GaF_2晶体，测量了激光损伤阈值。CaF_2晶体的LIIDT数随弯曲方式、表面光洁度和激光辐照次数的不同而不同。