Ion damage to the specimen in the SEM studied by the EBIC technique

Abstract

This paper reports ion damage to Si and GaAs diodes during examination in the SEM as revealed by the electron beam induced conductivity (EBIC) technique. Also reported here is the emission of energetic negative ions having a mass‐to‐charge ratio of 32 from the lanthanum hexaboride electron gun. It is believed that these ions are (O2)−, although the possibility that they might be S− cannot be ruled out. These ions give rise to damaged regions of the specimen which are circular in shape and which have a diameter related to that of the beam‐limiting aperture in the SEM final lens. It is presumed that this problem can be avoided, if necessary, by the use of an ion trap at some point in the electron column. Copyright © 1978 Foundation for Advances in Medicine and Science, Inc.