Selective etch process using hydrofluoric acid and ozone gases

US11791166B2 · kind B2 · utility

Assignees

• Beijing E-Town Semiconductor Technology Co., Ltd. · CN
• Mattson Technology, Inc. · US

Inventors

• Qi Zhang · State College, US
• Haichun Yang · Santa Clara, US
• Hua Chung · San Jose, US
• Ting Xie · Burtonsville, US
• Michael X. Yang · Palo Alto, US

Key dates

• Filing date: Nov 22, 2021
• Grant date: Oct 17, 2023
• Expiry date: Jan 1, 2042

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/32135
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

Systems and methods for etching titanium containing layers on a workpiece are provided. In one example, a method includes placing the workpiece on a workpiece support in a processing chamber. The workpiece includes a first layer and a second layer. The first layer is a titanium containing layer. The method includes admitting a process gas into the processing chamber. The process gas includes an ozone gas and a fluorine containing gas. The method includes exposing the first layer and the second layer on the workpiece to the process gas to at least partially etch the first layer at a greater etch rate relative to the second layer.