Low Accelerating Voltage Pitch Standard Based on the Modification of NBS (National Bureau of Standards) SRM (Standard Reference Material) 484

摘要

The National Bureau of Standards (NBS) is actively developing micrometer and submicrometer standards for the scanning electron microscope (SEM). This report summarizes the progress made to extend the imaging range of the presently available SRM 484 for use as an interim standard for low accelerating voltage magnification calibration applications for this instrument. NBS is actively developing micrometer and submicrometer standards for dimensional metrology in the SEM. The only magnification standard reference material (SRM) presently available for calibrating scanning electron microscopes is SRM 484. The standard provides a known pitch between gold lines in a nickel matrix and has proven useful for many SEM applications. However, SRM 484 was developed prior to the recent interest in nondestructive, low accelerating voltage SEM operation. The driving force for nondestructive inspection at low accelerating voltages has been the semiconductor industry for integrated circuit mask and wafer inspection and measurement.