Sidewall image transfer on magnetic tunnel junction stack for magnetoresistive random-access memory patterning

US10593870B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Hiroyuki Miyazoe · White Plains, US
• Nathan P. Marchack · White Plains, US
• HsinYu Tsai · White Plains, US
• Eugene J. O'Sullivan · Nyack, US
• Karthik Yogendra · Albany, US

Key dates

• Filing date: Dec 14, 2017
• Grant date: Mar 17, 2020
• Expiry date: Dec 14, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/0337
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A method of forming a semiconductor structure includes forming a first spacer material over two or more mandrels disposed over a magnetoresistive random-access memory (MRAM) stack. The method also includes performing a first sidewall image transfer of the two or more mandrels to form a first set of fins of the first spacer material over the MRAM stack, and performing a second sidewall image transfer to form a plurality of pillars of the first spacer material over the MRAM stack. The pillars of the first spacer material form top electrodes for a plurality of MRAM cells patterned from the MRAM stack.