US 2026/0305208 A1 · METHODS FOR REDUCING CRITICAL DIMENSION VARIATION

Abstract

A method is provided for processing a substrate to improve local critical dimension uniformity. The method includes providing a substrate in a process chamber, the substrate including a layer to-be-etched, a planarization layer over the layer to-be-etched, and a pattern transfer layer over the planarization layer. A plurality of openings are formed through the pattern transfer layer and the planarization layer, including a first opening with a first width and a second opening with a second width, the first width being different from the second width. A process gas is flowed in the process chamber and a radio frequency source power is applied to generate a plasma. The pattern transfer layer is bombarded with the plasma to form a modified surface layer that differentially seals top portions of the openings based on width differences. The modified surface layer is etched to expose the second opening while maintaining a seal over the first opening. The etching continues to increase the second width to a third width, reducing the dimensional difference between openings.

Claims20

Dependent claims

A method for processing a substrate, the method comprising:

providing a substrate in a process chamber, the substrate comprising a layer to-be-etched, a planarization layer disposed over the layer to-be-etched, and a pattern transfer layer disposed over the planarization layer;
forming a plurality of openings through the pattern transfer layer and the planarization layer, the plurality of openings comprising a first opening with a first width and a second opening with a second width, the first width being different from the second width;
flowing a process gas in the process chamber and applying a radio frequency (RF) source power to generate a plasma from the process gas;
bombarding the pattern transfer layer with the plasma to form a modified surface layer that differentially seals top portions of the first and the second openings based on a difference between the first width and the second width;
etching the modified surface layer to expose the second opening while maintaining a seal over the first opening;
and
continuing the etching to increase the second width of the second opening to a third width, wherein a difference between the third width and the first width is less than a difference between the second width and the first width.

4 more elements

Dependencies are inferred from the claim text.

Methods for reducing critical dimension variation

Life of this patent

Methods for reducing critical dimension variation

Life of this patent

Abstract

Claims20