Tokyo Electron Limited

International Business Machines Corporation

Hongyun Cottle

Chi-Chun Liu

Cheng Chi

Andrew W Metz

Kristin Schmidt

Techniques herein include an etch process that etches a layer of material incrementally, similar to mono-layer etching of atomic layer etching (ALE), but not necessarily including self-limiting, mono-layer action of ALE. Such techniques can be considered as quasi-atomic layer etching (Q-ALE). Techniques herein are beneficial to precision etching applications such as during soft-mask open. Techniques herein enable precise transfer of a given mask pattern into an underlying layer. By carefully controlling the polymer deposition relative to polymer assisted etching through its temporal cycle, a very thin layer of conformal polymer can be activated and used to precisely etch and transfer the desired patterns.

Method of quasi atomic layer etching

Graphoepitaxy directed self-assembly methods generally include grafting a conformal layer of a polymer brush onto a topographic substrate. A planarization material, which functions as a sacrificial material is coated onto the topographic substrate. The planarization material is etched back to a top surface of the topographic substrate, wherein the etch back removes the polymer brush from the top surfaces of the topographic substrate. The remaining portion of the polymer brush is protected by the remaining planarization material below the top surface of the topographic substrate, which can be removed with a solvent to provide the topographic substrate with a conformal polymer brush below the top surface of the topographic substrate. The substrate is then coated with a block copolymer and annealed to direct self-assembly of the block copolymer. The methods mitigate island and/or hole defect formation.

Graphoepitaxy directed self assembly

A method for selectively etching a substrate is described. The method includes preparing a substrate comprising a silicon nitride layer overlying a silicon-containing contact region, and patterning the silicon nitride layer to expose the silicon-containing contact region using a plasma etching process in a plasma etching system. The plasma etching process uses a process composition having as incipient ingredients a process gas containing C, H and F, and a non-oxygen-containing additive gas, wherein the non-oxygen-containing additive gas includes H, or C, or both H and C, and excludes a halogen atom.

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Schenectady, NY, United States of America

Hongyun Cottle