Imaging of a molecularly thin lubricant film on a magnetic disk by using ellipsometric microscopy

提出了一种磁盘表面分子润滑薄膜的直接可视化方法。分子薄膜的可视化是研究润滑剂薄膜的补充和保持的一种非常有用的技术。椭圆偏振法可以提供分子薄膜的厚度和折射率。然而，传统的椭圆偏振法需要扫描激光光斑以便对润滑剂膜成像，因为它只能提供样品表面的一个点的信息。本文提出了一种基于椭偏测量的直接可视化方法。在我们的椭偏显微镜，椭偏信息的样品表面被转换成明暗对比，并直接可视化与冷却CCD相机。通过光学和数字图像处理技术的结合，增强了弱对比度，降低了激光相干性引起的干涉噪声。因此，我们的方法可以提供1纳米级厚的薄润滑膜的直接可视化。

Direct visualization method for molecularly thin lubricant films on magnetic disks is presented. Visualization of a molecularly thin film is an extremely useful technique for the investigation of replenishment and retention of thin lubricant films. Ellipsometry can provide thickness and refractive index of a molecularly thin film. However, conventional ellipsometry requires the laser spot to be scanned in order to image a lubricant film, since it can provide information of only one point of a sample surface. In this report, direct visualization method based on ellipsometry is presented. In our elllipsometric microscope, ellipsometric information of a sample surface is converted into dark-bright contrast and is directly visualized with a chilled CCD camera. By the combination of optical and digital image processing techniques, weak contrast are enhanced and interference noise caused by laser coherence are reduced. Thus, our method can provide direct visualization of 1-nm order thick thin lubricant film.