Calibration is performed on an electron beam writer before each exposure. The machine needs to be calibrated to optimize its performance and produce reliable results. The degree of calibration needed depends on the requirements of the pattern. A routine calibration typically takes a several minutes to perform.
A routine calibration process typically involves two stages. The first stage requires the user to bring the machine to a reasonably calibrated state. In the second stage, the machine runs a program to automatically optimize the calibration parameters. A successful calibration will yield a focused beam with the desired current that can be scanned accurately within the scan field.