基于白光透射反射干涉的形貌重构方法验证

Morphology Reconstruction Method Validation Based on White-Light Transmission Reflection Interference

利用扫描白光干涉的测量方法,通过透射反射干涉的方式,对覆盖不同层数透明薄膜GaAs台阶结构进行透射测试,实现了对覆盖透明薄膜的GaAs台阶结构三维形貌还原方法的验证.该测量方法是在Pizeo的驱动下,通过改变测量臂和参考臂之间的光程差,使其不同高度的表面到达零光程差位置,并由CCD记录整个扫描过程中干涉条纹的变化状况,进而提取被测件的三维形貌信息.该测试技术具有非接触、无破损、高灵敏度和快速测量的特点.可为膜后形貌的三维重构提供借鉴方法.

The GaAs step structure, which was deposited different layers of thin film, was measured by the method of white light scanning and transmission reflection interference. And the reconstructed method of three-dimensional morphology for GaAs step structure was validated. As driven by Pizeo, the method changed the optical path difference （OPD） between the measurement arm and the reference arm, to make the different height of surface reach the position of zero OPD. The CCD was used to record the change of interference fringe in the whole scanning process, and the three-dimensional morphology information of the sample can be extracted. This measuring technique has characteristics of non-contact, nondestructive, high sensitivity and fast measurement.