Deflection data correction system of large areas electron beam direct imaging for printed wiring boards

A novel electron beam system for large-area patterning of printed wiring boards (PWBs) has been developed. The system features a large field deflection, high-scanning speed, and stably focused beam in the large field. In order to deflect electron beams in a large area with high precision, particular attention was paid to the construction of a deflection data correction system. Various errors originating from the optics are measured, and the data to correct for these errors are calculated and stored prior to imaging. These data are output to the optics column at a rate of up to 10 MHz during imaging. In addition, sensors provide the data to correct the position error originating from the height variations and warp of the PWB for each field. It is confirmed that the beam position precision is ±12 μm for a field of 52 mm×52 mm