Cross sectional scanning electron microscopy was used to study the dependence of gap fill capabilities in 0.25-2.0 mu m wide Al-Cu metal gaps of DuPont fluorinated polyimide films on solid content, adhesion promoter, spin dwell time, and solvent spray. It was found that reduced solid content, application of adhesion promoter and solvent spray improve gap fill capabilities. However, these improvements are insignificant. Spin dwell time has little effect on gap fill.