Liu Ming-Chung, Lee Cheng-Chung, Kaneko Masaaki, Nakahira Kazuhide, Takano Yuuichi
Thin Film Technology Center and Institute of Optical Science, National Central University, Chung-Li 320, Taiwan.
Appl Opt. 2006 Mar 1;45(7):1368-74. doi: 10.1364/ao.45.001368.
MgF2 and GdF3 materials, used for a single-layer coating at 193 nm, are deposited by a resistive-heating boat at specific substrate temperatures. Optical characteristics (transmittance, refractive index, extinction coefficient, and optical loss) and microstructures (morphology and crystalline structure) are investigated and discussed. Furthermore, MgF2 is used as a low-index material, and GdF3 is used as a high-index material for multilayer coatings. Reflectance, stress, and the laser-induced damage threshold (LIDT) are studied. It is shown that MgF2 and GdF3 thin films, deposited on the substrate at a temperature of 300 degrees C, obtain good quality thin films with high transmittance and little optical loss at 193 nm. For multilayer coatings, the stress mainly comes from MgF2, and the absorption comes from GdF3. Among those coatings, the sixteen-layer design, sub/(1.4L 0.6H)8/air, shows the largest LIDT.
用于193纳米单层涂层的MgF2和GdF3材料，通过电阻加热舟在特定的衬底温度下沉积。对光学特性（透过率、折射率、消光系数和光学损耗）和微观结构（形态和晶体结构）进行了研究和讨论。此外，MgF2用作低折射率材料，GdF3用作多层涂层的高折射率材料。研究了反射率、应力和激光诱导损伤阈值（LIDT）。结果表明，在300摄氏度的温度下沉积在衬底上的MgF2和GdF3薄膜，在193纳米处获得了具有高透过率和低光学损耗的高质量薄膜。对于多层涂层，应力主要来自MgF2，吸收主要来自GdF3。在这些涂层中，十六层设计sub/(1.4L 0.6H)8/空气显示出最大的LIDT。
