Method for forming a self-aligned bit line for PCRAM and self-aligned etch back process

US8445313B2 · kind B2 · utility

Assignees

• International Business Machines Corporation · US
• MACRONIX INTERNATIONAL CO., LTD. · TW

Inventors

• Matthew J. Breitwisch · Yorktown Heights, US
• Chieh-Fang Chen · Taipei, TW
• Shih-Hung Chen · Hengshan, TW
• Eric A. Joseph · White Plains, US
• Chung H. Lam · Williston, US
• Michael F. Lofaro · Milton, US
• Hsiang-Lan Lung · Ardsley, US
• Alejandro G. Schrott · New York, US
• Min Yang · Yorktown Heights, US

Key dates

• Filing date: Jul 11, 2012
• Grant date: May 21, 2013
• Expiry date: Jul 11, 2032

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10N70/8828

Abstract

A method of forming bit line aligned to a phase change material that includes forming a pedestal of a sacrificial material on a portion of a lower electrode and forming at least one dielectric material adjacent to the sacrificial material, wherein the at least one dielectric material has an upper surface substantially coplanar with an upper surface of the pedestal of the sacrificial material. The pedestal of the sacrificial material is removed selective to the at least one dielectric material and the lower electrode to provide an opening to an exposed surface of the lower electrode. A phase change material is formed on the exposed surface of the lower electrode, and the opening is filled with a conductive fill material. A self-aligned etch back process is also provided.