Dear Sir,

My design size is 800um*500um, I am exposing my design by EBL. I put this design at multiple coordinates like (u=3mm, V=3mm), (U=3mm, V=4mm) , (U=3mm, V=5mm) in position list after WF alignment and Sharp contamination dot (20nm) formation. Then I started the exposure scan. After development I found the middle design (U=3mm, V=4mm) get fully exposed and nicely developed, while first and last shows only doted pattern over the design after development. means where my design is beam traverse it exposes equally spaced dots.

I also tried to combine all three designs in single mask design then expose. in that case also not found full exposure of the pattern.

Is this related to WF alignment or any other issue? Experienced users please reply and suggest me the possible cause of such a problem.

Please help!!

Thanks