Tokyo Electron Limited

Erdinc Karakas

Alok Ranjan

Christopher Talone

Andrew Nolan

Sergey Alexandrovich Voronin

Hiroto Ohtake

Sonam D Sherpa

Shyam Sridhar

Li Wang

Provided is a method of modifying a surface of a substrate for improved etch selectivity of nitride etching. In an embodiment, the method includes providing a substrate with a nitride-containing structure, the nitride-containing structure having an oxygen-nitrogen layer. The method may also include performing a surface modification process on the nitride-containing structure with the oxygen-nitrogen layer using one or more gases, the surface modification process generating a cleaned nitride-containing structure. Additionally, the method may include performing a nitride etch process using the cleaned nitride-containing structure, wherein the etched nitride-containing structure are included in 5 nm or lower technology nodes, and the nitride etch process meets target etch rate and target etch selectivity, and the cleaned nitride-containing structure meet target residue cleaning objectives.

Methods of surface restoration for nitride etching

Plasma processing methods that provide for conformal etching of silicon nitride while also providing selectivity to another layer are described. In one embodiment, an etch is provided that utilizes gases which include fluorine, nitrogen, and oxygen, for example a gas mixture of SF, Nand Ogases. Specifically, a plasma etch utilizing SF, Nand Ogases at high pressure with no bias is provided. The process accelerates silicon nitride etching by chemical reactions of [NO]molecules from the plasma and [N] atoms from silicon nitride film. The etch provides a conformal (isotropic) etch that is selective to other materials such as silicon and silicon oxides (for example, but not limited to, silicon dioxide).

Method of conformal etching selective to other materials

A method of etching is described. The method providing a substrate having a first material composed of silicon-containing organic material and a second material that is different from the first material, forming a chemical mixture by plasma-excitation of a process gas containing SFand an optional inert gas, controlling a processing pressure at or above 100 mtorr, and exposing the first material on the substrate to the chemical mixture to selectively etch the first material relative to the second material.

Method of plasma etching of silicon-containing organic film using sulfur-based chemistry

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Portland, OR, United States of America

Erdinc Karakas