Patent ID: 11887822
Assignee: TOKYO ELECTRON LIMITED
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H | IPC H

Claim 5:
6. An etching apparatus comprising:
a plasma processing chamber;
a substrate support provided in the plasma processing chamber;
an edge ring to encircle an etching object supported by the substrate support, the edge ring including;
an inner edge-side portion toward the innermost circumference of the edge ring, relative to an intermediate line that is equidistant from the innermost circumference and the outermost circumference of the edge ring; and
an outer edge-side portion toward the outermost circumference of the edge ring, relative to the intermediate line,
wherein the inner edge-side portion and the outer edge-side portion have a ramp surface of which a height decreases from the outer edge-side portion toward the inner edge-side portion,
wherein the edge ring is configured to satisfy the relation of T2/T1>T4/T3, and wherein
T1 is a thickness of the edge ring, before plasma treatment, at a first position on the ramp surface of the inner edge-side portion,
T2 is a thickness of the edge ring, before plasma treatment, at a second position on the ramp surface of the outer edge-side portion,
T3 is a thickness of the edge ring, after plasma treatment, at the first position, and
T4 is a thickness of the edge ring, after plasma treatment, at the second position.