How to Spin Photoresist onto Wafers and Pieces

[@Jacob-og9pz]

Bravo for this

[@Ig0r1985]

what is the material of the pipette to dipense the photoresist? Does it need to be high density polyethylene (HDPE)?

[@alialhajaji7141]

Thikness of film seems to be not uniform 7:12.. What reasons could lead to that?

[@curian5]

Comet mark on the edge is caused by particle contamination. Chuck mark on center of the wafer is caused by difference in temperature due to evaporative cooling (chuck provides better thermal conductivity to chuck/wafer/photoresist stack, so center of the wafer is warmer than edges).