Demonstration of multiblanker electron-beam technology

Abstract

A set of multiple electron-beam (e-beam) aperture/blanker chips have been fabricated using silicon microelectro-mechanical systems (MEMS) techniques. The aperture sizes range from 8 to 4 μm (nominal) squares, and the chip configurations feature either eight individually controlled monopolar blanker electrodes or four bipolar electrode pairs. The chips replace the shapers of a 20 kV AEBLE™ shaped e-beam lithography column. The apertures in the chips convert an incident 150 μm diameter e-beam into multiple beamlets. Each beamlet can be independently blanked off of a 100 μm aperture placed at the following beam crossover. Data are presented that demonstrates the ability to independently blank each beamlet by applying 10 V. Magnified images of the beamlets show square or rectangular shapes with sharp corners, indicating that the apertures were properly fabricated. The degree of electrostatic blanker crosstalk was measured and found to be up to 15% at the crossover plane for different pairs of beamlets, but no observable beam displacement occurred at the image plane. We compared the experimental results to a rough model that estimates the effect of the electrostatic field distribution of one excited blanker electrode on the unblanked beams. The results matched to within 20%.