Critical dimension measurements by electron and optical beams for the establishment of linewidth standards

To establish traceability in sub-micrometer critical dimension measurements, a silicon reference artifact was manufactured. The measurement characteristics of the artifacts were examined by simulation and a metrological scanning electron microscope system. The possibility of linewidth indication by a peak-to-peak definition for isolated lines is described, and a pitch reference by a silicon grating was examined. A simulation based on a diffusion theory is described to predict the edge signal for the electron beam line scan on the artifact. It predicted narrower linewidth for isolated lines and showed good agreement with experimentally obtained critical dimensions