Method of depositing a pre-etch protective layer

US11915940B2 · kind B2 · utility

Assignee

• Applied Materials, Inc. · US

Inventors

• Zhi-Gang Wang · Palo Alto, US
• Jiao Yang · Xi'an, CN
• Alfredo Granados · San Antonio, US
• Jon C. Farr · Tempe, US
• Heng Wang · Holmdel, US
• Rui Ren · Tuji, CN

Key dates

• Filing date: Jul 2, 2021
• Grant date: Feb 27, 2024
• Expiry date: Dec 24, 2041

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/32139
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method of cyclic etching, comprising: (A) depositing, prior to cyclically etching a substrate through a mask opening, a pre-etch protection layer conformally over the mask, sidewalls of the mask defining the mask opening; and an exposed portion of the substrate exposed through the mask opening, the pre-etch protection layer deposited to a first thickness; and (B) cyclically etching the substrate by: (i) depositing a protection layer in the opening of the mask, the protection layer deposited to a second thickness that is less than half of the first thickness; (ii) etching through a portion of the protection layer disposed on the substrate and etching the substrate; and (iii) repeating (i) and (ii) until an end point is reached.