Figure 5. Shows the effect of resist loading on the fall off in the pH of the developer
solution. The breakpoint will increase as the resist loading increase in the developer
solution. This will cause incomplete developing resulting in resist scum and bad
resolution.
In a batch solution, the resist loading is 3.2 ~ 4.0 mil·ft2/ L (12 ~ 14 mil·ft2/ gal).
Developer solution should be replaced as resist loading up to this high level. Use
flowing guidelines to change solution.