• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>ICO20: Optical Devices and Instruments >Sinusoidal wavelength-scanning interferometer for measurement of thickness and surface profile of thin films
【24h】

Sinusoidal wavelength-scanning interferometer for measurement of thickness and surface profile of thin films

机译：用于测量薄膜厚度和表面轮廓的正弦波扫描干涉仪

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

We propose a sinusoidal wavelength scanning interferometer for measuring thickness and surfaces profiles with a thin film. An acousto-optic tunable filter (AOTF) is used to produce sinusoidally wavelength-scanned light from a superluminescent laser diode (SLD) with a wide spectral bandwidth of 46nm. The interference signal contains an amplitude Z_b of a time-varying phase and a constant phase α. Two measured values of OPD, which are denoted by L_z and L_α, are obtained from Z_b and α. By combining L_z and L_α, an OPD longer than a wavelength is measured with an error less than a few nanometers. When the object has two reflective surfaces, the detected interference signal contains two interference signals which are caused by the front and rear surfaces. In this case we must determine the values of Z_(b1), Z_(b2), α_1, and α_2, where suffixes of 1 and 2 are corresponding to the front and rear surfaces, respectively. We define an error function that is the difference between the detected signal and the theoretical signal, and reduce the value of the error function with the multidimensional nonlinear least-squares algorithm to search the values of Z_(b1), Z_(b2), α_1, and α_2. Experimental results show that the thickness and surfaces profiles of a silica glass plate of 20μm-thickness are measured with error less than 1.5nm.
机译：我们提出一种正弦波波长扫描干涉仪，用于测量薄膜的厚度和表面轮廓。声光可调滤光片（AOTF）用于从超发光激光二极管（SLD）产生具有46nm宽光谱带宽的正弦波长扫描光。干扰信号包含时变相位和恒定相位α的振幅Z_b。从Z_b和α获得两个OPD测量值，分别由L_z和L_α表示。通过组合L_z和L_α，以小于几纳米的误差来测量比波长更长的OPD。当物体具有两个反射面时，检测到的干扰信号包含两个由前表面和后表面引起的干扰信号。在这种情况下，我们必须确定Z_（b1），Z_（b2），α_1和α_2的值，其中后缀1和2分别对应于前表面和后表面。我们定义一个误差函数，该误差函数是检测到的信号与理论信号之间的差，并使用多维非线性最小二乘算法减少误差函数的值，以搜索Z_（b1），Z_（b2），α_1的值和α_2。实验结果表明，对厚度为20μm的石英玻璃板的厚度和表面轮廓进行了测量，误差小于1.5nm。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号