The development of a successful fabrication process for electron devic
es with dimensions in the sub-100-nm domain will require a form of a h
igh-resolution and high-volume patterning. In this paper we discuss th
e extensibility of X-ray lithography to this domain in terms of the re
solution of the technique, considering in detail the effect of diffrac
tion and photoelectrons. We show that optimized masks and exposure sys
tems can deliver with relative ease patterning in the 70-50-nm region,
while phase-shifting techniques can extend the resolution to sub-40 n
m. High volume is provided by the use of the mask. The challenge remai
ns in the fabrication of the 1X mask, and in the achievement of the ne
cessary placement accuracy.