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

• 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
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11450063/
• 关键词: Atomic surface structure analysis; Float polishing; Calcium fluoride; Deep ultra violet laser; Laser induced damage threshold; Micro lithography; フロートポリシング; 超精密加工; 表面原子構造; フッ化物結晶; 超精密研削; 超精密ダイヤモンド切削; 透過率

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.

高亮度的深度超紫色（DUV）激光被预期是下一代微光谱学，由于光化学反应和激光融合而引起的激光微处理的光源。但是，存在严重的问题，例如要传输光学材料的局限性，缺乏高精度和激光诱导材料损坏的光学材料的经验。这项研究工作旨在提出高精度，高透射率，高激光诱导的损伤阈值（LIDT）和高可靠性的高亮度的DUV激光器的平坦光学组件。将DUV的晶体抛光，并在浮子抛光表面上获得表面粗糙度为0.16nm RM，并用原子力显微镜（AFM）测量。从具有高压透射电子显微镜（HVTEM）的观察结果，可以澄清的是，浮子抛光的表面显示出完美的（111）晶格和小原子步骤，地下没有损坏。我们通过使用ND：YAG激光器的KDP和CLBO的非线性晶体获得了波长266nm的第四个谐波激光器。从GAF_2晶体上激光的辐照，测量了Lidt。在各种弯曲器中的CAF_2晶体，表面饰面和激光辐照数中，LIIDT数字不同。

项目成果

Y.Namba: "Development of Ultraprecision Machining Technology for Functional Optical Materials"Review of Laser Engineering. 27,9. 599-604 (1999)

Y.Namba：“功能光学材料超精密加工技术的发展”激光工程评论。

Y.Namba: "Modeling and Measurements of Atomic Surface Roughness"Appl.Opt.. 39巻16号. 2705-2718 (2000)

Y.Namba：“原子表面粗糙度的建模和测量”Appl.Opt.。第 39 卷，第 16 期。2705-2718 (2000)

宇野義幸: "プラスチックのレーザフォーミングに関する研究 -試料厚さが変形特性に及ぼす影響-"精密工学会誌. 68・3. 466-471 (2002)

Yoshiyuki Uno：“塑料激光成形研究 - 样品厚度对变形性能的影响 -” 日本精密工程学会杂志 68・3（2002 年）。

Y.Namba: "Precision Machining of Optical Materials for UV Applications"Jpn.J.Optics. 30,12. 801-807 (2001)

Y.Namba：“用于紫外应用的光学材料的精密加工”Jpn.J.Optics。

J.Yu: "Surface Roughness Limit for Super-Machined Mirrors Measured with Scanning Probe Microscopy"Proc.ASPE 14ty Annual Meeting. 368-371 (1999)

J.Yu：“用扫描探针显微镜测量的超加工镜子的表面粗糙度极限”Proc.ASPE 14ty 年会。