David Lanzendörfer schreef op vr 10-04-2020 om 19:35 [+0100]:
Hi everyone So last Sunday, Ferenc and I brainstormed on how to achieve smaller feature sizes with a UV wave length, which limits us to 400nm or so. We discussed splitting a lower feature size layout into multiple masks and then doing overlapping exposure steps. Ferenc pointed out, that we might run into an offset issue. I've been thinking about this for a while and the solution came to me on the toilet just now, and it's actually surprisingly simple. Since we're using a DMD and not physical masks, we can do the multiple exposure steps all at once, without any stepping in between.
while(!eow()) { // end of wafer expose_mask(1); expose_mask(2); step_to_next(); }
This is not going to work. What you basically will be doing is adding two sinusoidal intensity profiles with half the period shifted on top of each other giving almost not modulation of the intensity anymore. There is not reason why this would only be possible with DMD and not with two physical masks.
greets, Staf.