Memory device and method for forming the same

US11563021B2 · kind B2 · utility

Assignee

• YANGTZE MEMORY TECHNOLOGIES CO., LTD. · CN

Inventors

• Bo Huang · 红钢城街道, CN
• Lei Xue · 红钢城街道, CN
• Jiaqian XUE · Hubei, CN
• Tingting Gao · 红钢城街道, CN
• Wanbo Geng · 红钢城街道, CN
• Xiaoxin Liu · 红钢城街道, CN

Key dates

• Filing date: Jun 4, 2020
• Grant date: Jan 24, 2023
• Expiry date: Jan 19, 2041

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D64/037

Abstract

A method for forming a memory device includes providing an initial semiconductor structure, including a base substrate; a first sacrificial layer formed on the base substrate; a stack structure, disposed on the first sacrificial layer; a plurality of channels, formed through the stack structure and the first sacrificial layer; and a gate-line trench, formed through the stack structure and exposing the first sacrificial layer. The method also includes forming at least one protective layer on the sidewalls of the gate-line trench; removing the first sacrificial layer to expose a portion of each of the plurality of channels and the surfaces of the base substrate, using the at least one protective layer as an etch mask; and forming an epitaxial layer on the exposed surfaces of the base substrate and the plurality of channels.