A High Resolution Sub-Micron Retarding Field Energy Analyzer for Low Temperature Plasma Analysis

A retarding potential energy analyzer having 750 nm diameter, self-aligned grid apertures and micron scale grid separation has been fabricated using polycrystalline silicon and silicon dioxide. High resolution in situ measurements of ion velocity distributions have been demonstrated in inductively coupled argon plasmas. Measurement results agree well with those from a macroscopic analyzer. Important differences are observed in the energies of plasma ions when measured with respect to chamber wall versus those measured with respect to the plasma floating potential. Preliminary measurements under rf bias conditions have also been made and results follow the expected trends