Apparatus and method for measuring lengths in a scanning particle microscope

摘要

A method and apparatus for measuring lengths in a scanning particle microscope employ a device for generating a particle beam directed toward a specimen stage on which a specimen is mounted. A second stage is placed over the specimen stage above the specimen, the second stage carrying a calibrated grid structure covering the region of the specimen to be measured. The grid structure is disposed a distance from the specimen which is less than or equal to the depth of focus of the apparatus. The grid structure is of known dimensions, and is utilized to provide bench marks for measuring distances on the specimen, and can be displaced as needed to measure longer distances.