“…6,8,9 However, ECL is a parallel illumination method which can simultaneously illuminate large areas of the resist, ameliorating the requirements for large beam currents. 8,10 In addition, dual beam LEEM methods have been shown to reduce the effect of the electron beam on the mirror itself, which causes some mirror surfaces to change potential and distort the outgoing electron beam. 10 ECL is entirely compatible with a multiple column architecture which can, in principle, reduce the required beam current in any one column, and realise several tens of wafers per hour.…”