Investigation of defect detectability for extreme ultraviolet patterned mask using two types of high-throughput electron-beam inspection systems

Abstract

"Investigation of defect detectability for extreme ultraviolet patterned mask using two types of high-throughput electron-beam inspection systems," J. Abstract. Defect detectability using electron-beam (EB) inspection for an extreme ultraviolet (EUV) mask was investigated by comparing a projection electron microscope (PEM) and a scanning electron microscope (SEM) inspection system. The detectability with EB does not coincide with the printability data because the contrasts of the EUV aerial image and EB image for EUV mask are reversed. The 16-nm-sized defect on a half-pitch 64-nm line and space (L/S) pattern is detected even when the line edge roughness is taken into account in both PEM and SEM inspections by applying a special algorithm for image processing. The required and robust inspection conditions, such as the number of electrons per pixel and pixel size (resolution), were examined for an SEM inspection system. The throughput of the PEM inspection system corresponds to that of the multibeam SEM one with 200 to 1850 beams. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Electron microscopy in semiconductor inspection

“…Iida et al [51] have investigated the defect detectability of EUV masks by comparing PEM and SEM inspection systems. See figure 1 (a schematic diagram of the PEM inspection system) in [51].…”

“…Iida et al [51] have investigated the defect detectability of EUV masks by comparing PEM and SEM inspection systems. See figure 1 (a schematic diagram of the PEM inspection system) in [51]. In PEM, PEs covering a large area illuminates the mask surface, and the emitted SEs reach the detector via imaging electron optics.…”