Equipment and Method for Improved Edge Uniformity of Plasma Processing of Wafers
AssigneeTokyo Electron Limited
InventorsBarton Lane, Peter Lowell George Ventzek
Life of this patent
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Abstract
What is described is an equipment for plasma processing including: a pedestal configured to hold a wafer; concentric with the pedestal, a focus ring including an insulator, the focus ring being positioned close to an edge region of the wafer when the wafer is held on the pedestal; and a plurality of gas discharge devices embedded in the focus ring, where each gas discharge device is configured to generate a gas discharge plasma confined within the focus ring.
Claims20
An equipment for plasma processing comprising:
- a pedestal configured to hold a wafer;
- concentric with the pedestal, a focus ring comprising an insulator, the focus ring being positioned close to an edge region of the wafer when the wafer is held on the pedestal;
- and
- a plurality of gas discharge devices embedded in the focus ring, wherein each gas discharge device is configured to generate a gas discharge plasma confined within the focus ring.
The equipment of claim 7, wherein the inductive structure is a two-terminal inductor (L) and the capacitive structure is a two-terminal capacitor (C), the terminals being connected in a parallel LC resonant circuit configuration.
A plasma processing system, the system comprising:
- a plasma process chamber;
- a pedestal configured to hold a wafer inside the chamber;
- a first radio frequency (RF) power supply coupled to a first RF electrode, the first RF electrode being configured to generate direct plasma over the pedestal using RF source power from the first RF power supply;
- located in the chamber, a radical distribution plenum having a plurality of exit holes arranged circularly around an edge of the wafer when the wafer is held on the pedestal, wherein the plenum is configured to receive a flow of radicals and distribute the flow out to the chamber through the plurality of exit holes;
- and
- a radical source coupled to the plenum, the radical source being configured to flow radicals into the plenum and, wherein the radical source is different from the direct plasma.
A method of plasma processing comprising:
- from a primary radical source, generating a main flow of radicals directed toward a major surface of a wafer disposed on a pedestal inside a plasma process chamber;
- from a secondary radical source, generating a supplemental flow of radicals directed toward an edge region of the major surface, the generating the supplemental flow of radicals comprising flowing radicals through a plurality of exit holes of an annular radical distribution plenum disposed in the chamber around an edge of the wafer;
- and
- exposing the major surface to a combined flow of radicals, the combined flow being a combination of the main flow and the supplemental flow.
Dependencies are inferred from the claim text.