Hi I'm apparently not the first one with the idea to use a DMD chip and an UV light source for exposure: https://www.researchgate.net/figure/Layout-for-UV-based-DMD-system-If-the-il...
There are actually parts available: http://www.ti.com/product/DLP9500UV http://www.ti.com/product/DLP9000XUV
For those chips, the UV wave length would be around 360nm
The price on Mouser is 8888 USD, so around 9 thousand USD
The chip is exactly made for mask less lithography systems as the one I wanna build, it's even mentioned in the data sheet: http://www.ti.com/lit/ds/symlink/dlp9500uv.pdf
By optimizing the aperture of the lens system, this means that one could perfectly fine produce feature sizes down to 150 nm or so, maybe even smaller.
I wonder, whether we should make a gofundme campaign for buying the required second hand stepper and this chip... Hmm.
Also. Since this chip is super expensive, we will need to *really* make sure, that there's no mistake in the PCB, because we only have one attempt.
Cheers -lev