Methods of making word lines and select lines in NAND flash memory

US9153595B2 · kind B2 · utility

Assignee

• Sandisk Technologies, Inc. · US

Inventors

• Jongsun Sel · Los Gatos, US
• Tuan Pham · Santa Clara, US
• Kazuya Tokunaga · Kumamoto, JP

Key dates

• Filing date: Sep 14, 2012
• Grant date: Oct 6, 2015
• Expiry date: Feb 14, 2034

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D89/10

Abstract

A NAND flash memory chip includes word lines formed by etching through concentric conductive loops and, in the same etch step, etching through a conductive strip to form select lines. A conductive loop forms two word lines which are in different erase blocks and are separately controlled by peripheral circuits.