Automatic measurement of electron-beam diameter and astigmatism: BEAMETR

Beam size is one of the major characteristics of any electron beam system. Accuracy and resolution of SEM and an EBL system directly depend on beam diameter; it should be monitored and tuned frequently. Currently used methods are not accurate and are operator dependent. A technique is described to determine beam size using an automatic procedure. In the developed method, a specially designed and fabricated test pattern is scanned using an e-beam. A spectra of the signal is analyzed; beam diameter is automatically determined using a software program. Results of design, fabrication, and analysis of the beam calibration test pattern are presented. (C) 2008 Elsevier B. V. All rights reserved.