Measurement of Line-width and Line-width Roughness Based on Equivalent Area
LI Hong-bo1,2,ZHAO Xue-zeng2,ZHAO Wei-qian1
1. School of Optoelectronics, Beijing Institute of Technology, Beijing 100081, China
2.AVIC Changcheng Institute of Metrology, Beijing 100095, China
3. School of Mechanical and Electrical Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001, China
Abstract：A method to measure line-width and line-width roughness (LWR) is presented based on the outline feature of the step scanned by AFM. Ideally, the step cross-section along the direction of the line-width is rectangle, whose area, S, is the product of height and line-width. Actually, the outline of the step cross-section is polygonal, whose area, S1, is equaled to S. The height of the profile scanned by AFM, H, is calculated by improving Tsai’s height algorithm. So, line-with, We, is calculated according to S1 and H. LWR is also calculated according to its definition as the 3σ value of line-width variation.
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2011, Vol. 32 
