Magnetoresistive random access memory

• US 8,743,596 B2
• Filed: 11/29/2012
• Issued: 06/03/2014
• Est. Priority Date: 11/05/2012
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Annunziata, Anthony J.
• Primary Examiner(s): Byrne, Harry W
• Application Number:
  US13/689,052
• Publication Number:
  US 20140127830A1
• Time in Patent Office: 551 Days
• Field of Search: 365/48, 365/55, 365/62, 365/66, 365/74, 365/78, 365 80- 93, 365/100, 365/130, 365/131, 365/148, 365/158, 365171-173, 365/209, 365/213, 365/225.5, 365/230.07, 365/232, 365/243.5, 257/421, 257/E21.665, 438/3, 428810-816, 428817-8251, 428/826, 977933-935
• US Class Current: 365/158
• CPC Class Codes: G11C 11/161 details concerning the memory cell structure, e.g. the layers of the ferromagnetic memory cell
• CPC Class Codes: G11C 11/1659 Cell access
• CPC Class Codes: G11C 11/1673 Reading or sensing circuits or methods
• CPC Class Codes: G11C 11/1675 Writing or programming circuits or methods
• CPC Class Codes: G11C 11/1697 Power supply circuits
• CPC Class Codes: H10N 50/01 Manufacture or treatment
• CPC Class Codes: H10N 50/10 Magnetoresistive devices

Abstract

A method of forming a magnetoresistive random access memory (MRAM) apparatus includes forming a first conductive line on a first insulating layer, forming a second insulating layer on the first conductive line and forming a magnetic tunnel junction through the second insulating layer to contact the first conductive line. The method also includes forming a cavity adjacent to the magnetic tunnel junction in the second insulating layer and forming a second conductive line on the second insulating layer to contact the magnetic tunnel junction.

Claims

1. A method of forming a magnetoresistive random access memory (MRAM) apparatus, comprising:

forming a first conductive line on a first insulating layer;

forming a second insulating layer on the first conductive line;

forming a magnetic tunnel junction through the second insulating layer to contact the first conductive line;

forming a cavity adjacent to the magnetic tunnel junction in the second insulating layer; and

forming a second conductive line on the second insulating layer to contact the magnetic tunnel junction.

2. The method of claim 1, wherein forming the cavity includes etching the second insulating layer.

3. The method of claim 2, wherein forming the cavity comprises:

forming a self-arranging polymer on the second insulating layer, the self-arranging polymer forming holes of predetermined sizes at regular intervals; and

applying an acid to the second insulating layer through the self-arranging polymer to form the cavity.

4. The method of claim 1, wherein the cavity is formed by photolithography.

5. The method of claim 1, further comprising:

forming a conductive write line; and

forming the first insulating layer on the conductive write line,

wherein the magnetic tunnel junction is formed above the conductive write line.