New method of 2-dimensional metrology using mask contouring

摘要

We have developed a new method of accurately profiling and measuring of a mask shape by utilizing a MaskCD-SEM. The method is intended to realize high accuracy, stability and reproducibility of the MaskCD-SEM adopting an edge detection algorithm as the key technology used in CD-SEM for high accuracy CDmeasurement. In comparison with a conventional image processing method for contour profiling, this edgedetection method is possible to create the profiles with much higher accuracy which is comparable withCD-SEM for semiconductor device CD measurement. This method realizes two-dimensional metrology forrefined pattern that had been difficult to measure conventionally by utilizing high precision contour profile.In this report, we will introduce the algorithm in general, the experimental results and the application inpractice.