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An improved focus ring is configured for use in a plasma processing chamber. The focus ring is configured to overlap at least a portion of a substrate-holding chuck that is powered by radio frequency (RF) power during plasma operation to act as an electrode. The focus ring includes an upper surface that is exposed to a plasma region within the plasma processing chamber during the plasma operation. The focus ring further includes a chuck-overlapping portion that overlaps the portion of the substrate-holding chuck, at least a portion of the chuck-overlapping portion being formed of a first material having a lower dielectric constant than a remainder of the focus ring.