Embodiments provided herein generally include apparatus, e.g., plasma processing systems and methods for the plasma processing of a substrate in a processing chamber. In some embodiments, aspects of the apparatus and methods are directed to improving process uniformity across the surface of the substrate, reducing defectivity on the surface of the substrate, or both. In some embodiments, the apparatus and methods provide for improved control over the uniformity of a plasma formed over the edge of a substrate and/or the distribution of ion energies at the surface of the substrate. The improved control over the plasma uniformity may be used in combination with substrate handling methods, e.g., de-chucking methods, to reduce particulate-related defectivity on the surface of the substrate. In some embodiments, the improved control over the plasma uniformity is used to preferentially clean accumulated processing byproducts from portions of the edge ring during an in-situ plasma chamber cleaning process.