Comparison of SEM and HRTEM CD measurements extracted from test-structures having feature linewidths from 40 nm to 240 nm

CD (critical dimension) measurements have been extracted from SEM (scanning electron microscope) and HRTEM (high resolution transmission electron microscopy) images of the same set of monocrystalline silicon features having linewidths between 40 and 240 nm. The silicon features are incorporated into a new test structure that has been designed to facilitate this type of CD-metrology study. The purpose of the work was to characterize the calibration statistics of SEM transfer-metrology when HRTEM is used as primary metrology in CD reference material calibration.