Journal of Vacuum Science & Technology B, Vol.18, No.6, 2999-3003, 2000
Scaled measurements of global space-charge induced image blur in electron beam projection system
Previous results on simulations of space-charge induced blur in electron projection systems indicated serious limitations on throughput particularly as minimum feature sizes (MFSs) are reduced below 100 nm. For example, a 40-cm-long 50 kV column might have a maximum throughput of only 0.2 cm(2)/s at MFS=50 nm CR. F. W. Pease et nl., MNE, Italy, 1999]. Direct experimental verification is difficult, so we have developed a set of theory-based scaling laws for electron optics and have carried out a series of experiments for verifying these laws. Our experimental results support the earlier predictions and also confirmed that: shortening the column length to the minimum allowed by the maximum practical focusing field strengths (e.g., 1 T and 10(7) V/m) should bring about dramatic (20- to 50-fold) improvements.