Earl T. Hackett, Jr. wrote:
> The need for collumination depends upon the spaces you are trying to maintain. If you are shooting for less than 5 or 6 mils it's important. If your exposure time is longer that 1 minute (I didn't like to see it longer than 30 seconds) don't worry about collumination, get more lamps. You can overcome poor columination with intensity. The old Scanex's had crappy columination, but the effective exposure time was around 5 seconds and they worked pretty well.
> ----- Original Message -----
Overall light energy and collumination are completely separate
parameters with respect to photoresists. More photons simply means a
faster photochemical reaction. Point blank range fluorescent tubes can
expose in seconds, however light undercutting is terrible.
Adam