Patent ID: 11869749
Assignee: SEMES CO., LTD.
Field: Semiconductors (Electrical engineering)
Classification: CPC H | IPC H

Claim 10:
11. A substrate processing apparatus comprising:
a lower electrode to which a radio frequency (RF) power source is electrically connected for generating plasma;
an edge electrode electrically insulated from the lower electrode;
an edge impedance controller electrically connected to the edge electrode to control an electrical potential of the edge electrode;
a coupling compensator connected between the lower electrode and the edge electrode and configured to prevent the RF power applied to the lower electrode from leaking to the edge electrode and to enable the edge impedance controller to control the electric potential of the edge electrode independently from the lower electrode by canceling or adjusting a capacitive coupling between the lower electrode and the edge electrode; and
a ring member configured to prevent the edge electrode from being exposed to the plasma: wherein the ring member comprises:
a first ring member provided to surround a circumference of a substrate that is supported by a first portion of the lower electrode;
a second ring member formed of an insulation material and disposed under the first ring member to surround a circumference of the first portion of lower electrode; and
a third ring member vertically disposed between a lower surface of the first ring member and a second portion of the lower electrode, and horizontally disposed between the first portion of the lower electrode and a side portion of the second ring member,
wherein the lower surface of the first ring member covers an entire upper surface of the third ring member, and
wherein the entire upper surface of the third ring member is positioned at the same height as an uppermost surface of the second ring member.