Addressing 3D metrology challenges by using a multiple detector CDSEM

摘要

In next generation lithography (NGL) for the 22nm node and beyond, the three dimensional (3D) shape measurements of side wall angle (SWA) and height of the photomask pattern will become critical for controlling the exposure characteristics and wafer printability. Until today, cross-section SEM (X-SEM) and Atomic Force Microscope (AFM) methods are used to make 3D measurements, however, these techniques require time consuming preparation and observation. This paper presents an innovative technology for 3D measurement using a multiple detector CDSEM and reports its accuracy and precision.