Methods for forming three-dimensional memory devices with channel structures having plum blossom shape

US11877449B2 · kind B2 · utility

Assignee

• YANGTZE MEMORY TECHNOLOGIES CO., LTD. · CN

Inventors

• Wanbo Geng · 红钢城街道, CN
• Lei Xue · 红钢城街道, CN
• Xiaoxin Liu · 红钢城街道, CN
• Tingting Gao · 红钢城街道, CN
• Weihua Cheng · Hubei, CN

Key dates

• Filing date: Oct 30, 2020
• Grant date: Jan 16, 2024
• Expiry date: Jul 22, 2042

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10B43/10

Abstract

Embodiments of three-dimensional (3D) memory devices and methods for forming the same are disclosed. In an example, a method for forming a 3D memory device is disclosed. A channel hole extending vertically above a substrate and having a plum blossom shape in a plan view is formed. A continuous blocking layer, a continuous charge trapping layer, and a continuous tunneling layer each following the plum blossom shape are formed from outside to inside in this order along sidewalls of the channel hole. A plurality of separate semiconductor channels each disposed over part of the continuous tunneling layer at a respective apex of the plum blossom shape are formed.