Metrology standards for advanced semiconductor lithography referenced to atomic spacings and geometry

Abstract

It is shown how the needs for calibrating the positional accuracy of features of an X-ray mask membrane or an optical reticle can be addressed by application of a high-accuracy coordinate metrology system known as the Molecular Measuring Machine (M-Cubed). Based on scanning tunneling microscopy and state-of-the-art heterodyne optical interferometry, the measurements of M-Cubed are referenced to fundamental standards of length and angle and with the atomic-resolution of its scanning tunneling microscope probe are validated against the interatomic spacings and geometry of single crystal surfaces. Through the use of a stable reference grid, serving as an intermediate calibration artifact, the positional accuracy of features on an X-ray mask membrane or an optical reticle can be referenced to fundamental standards of length and angle by means of the metrology system of M-Cubed.<>