I am using 3-inch SiC substrate for fine linewidth lithagraphy on SUSS
MJB3. PR 5214, eith positive process or image reversal. There band
formation on wafer edge, those band areas are poorly developed. The
puzzle is when I use 3-inch Si then no such band.
        Also I have same problem with 2-inch SiC wafer on 2-inch chuck. But
There
is no problem when I use 2-inch SiC wafer on 3-inch chuck. But MJB3 only
support upto 3-inch chuck!
        Using black tapes to cover wafer chuck doesn't help.
I wonder anti-reflective coating will do any good? But it will complicate
process...
Anyone doing litha on transparent substrate has any advice? Thanks.