Ah the heady mix of intellectual arrogance and gaelic intransigence. C'est chic.
European Silicon Structures ES2 2.0 anyone?
30 years later the issue is still getting enough wafers through the system except the wafers are now 300mm, not 100mm and the # of masks is about 3x higher (although in principle ebeam is also maskless).
Back in the early 80s one of the UK silicon vendors (when there still were UK silicon vendors), possibly Plessey, came up with an ebeam system using (IIRC) a UV source to trigger electron emission from multiple micro-electrodes using either a metal grid or field emission electron array to generate 100s of copies at the same time at unheard of line widths (100s of nm when the SoA was 1micrometre+).
Obviously a more sensitive ebeam resist would help quite a lot here.
The problem comes down to this. Electrons are the obvious way to go. There is a lot of tech that has been developed to generate and steer electrons and their natural size is sub nanometre by default. But everyone wants throughput and that's always been the achilles heel.
The foundries reckon throughput --> 1 shot whole wafer exposure --> Xray (let's can this "EUV" BS).
But there are other options. Despite my jibe at the start I like the fact they are still running with this so thumbs up to them.