As critical dimensions shrink to sub-100nm node and below in the semiconductor industry

the measure and control line edge roughness (LER) in nanometer-scale measurement has become critical. The problem of the influence factors of measuring semiconductor line edge roughness (LER) using AFM is studied. Aim at the current LER measurement method the influence factors of measuring precision are analyzed

including the nonideal property of the size and shape of probe tips

the signal noise of AFM image

scan sampling interval

the driving precision of piezoelectricity

cantilever oscillation and the free parameters of edge detection algorithm and so on. In this paper the influence factors of measuring LER using AFM are analyzed theoretically and the methods for restraining and amending the measure errors are respectively proposed. Accordingly a more precise measurement result of LER using AFM is obtained. In addition

a theoretical reference is provided in order to achieve the request on the improving measurement precision of line structure topography measurement in the semiconductor industry.