The first NIST-traceable SEM magnification calibration standard designed to meet the particular needs of the micromanufacturing industry has been fabricated and characterized in production prototype form. The SRM 2090A samples contain structures ranging in pitch from 3000 micrometers to 0.2 micrometers and are useful at both high and low accelerating voltages. The samples are fabricated using electron beam lithography and metal liftoff on a silicon substrate. Since the low-accelerating voltage, critical-dimension measurement scanning electron microscope has assumed an important role in modern semiconductor process control, the use and performance of the samples in a representative instrument is investigated. For all types of scanning electron microscopes, magnification calibration depends on several operating conditions, including magnification, accelerating voltage, and working distance. Implementation and application of the calibration factors within the SEM computer operating system can facilitate routine magnification calibration processes.
Proceedings Title: Proceedings of SPIE, Microlithography and Metrology in Micromachining, Michael T. Postek, Editor
Conference Dates: October 23, 1995
Conference Location: Austin, TX
Conference Title: Metrology in Microfabrication II
Pub Type: Conferences
calibration, CD?SEM, electron beam lithography, SRM 2090A, standards