Ta2O5 Interfacial Layer between GST and W Plug enabling Low Power Operation of Phase Change Memories

Author

Matsui, Y. ; Kurotsuchi, K. ; Tonomura, O. ; Morikawa, T. ; Kinoshita, M. ; Fujisaki, Y. ; Matsuzaki, N. ; Hanzawa, S. ; Terao, M. ; Takaura, N. ; Moriya, H. ; Iwasaki, T. ; Moniwa, M. ; Koga, T.

Author_Institution

Central Res. Lab., Hitachi, Ltd., Tokyo

fYear

2006

fDate

11-13 Dec. 2006

Firstpage

1

Lastpage

4

Abstract

A novel memory cell for phase-change memories (PCMs) that enables low-power operation has been developed. Power (i.e., current and voltage) for the cell is significantly reduced by inserting a very thin Ta₂O₅ film between GeSbTe (GST) and a W plug. The Ta₂O₅ interfacial layer works not only as a heat insulator enabling effective heat generation in GST but also as an adhesion layer between GST and SiO₂ underneath. Nonetheless, sufficient current flows through the interfacial layer due to direct tunneling. A low programming power of 1.5 V/100 muA can therefore be obtained even on a W plug with a diameter of 180 nm fabricated using standard 0.13-mum CMOS technology. In addition, the uniformity and repeatability of cell resistance are excellent because of the inherently stable Ta₂O₅ film properties

Keywords

CMOS memory circuits; antimony compounds; germanium compounds; low-power electronics; phase change materials; silicon compounds; tantalum compounds; tunnelling; 0.13 micron; CMOS technology; GeSbTe; SiO₂; Ta₂O₅; W plug; direct tunneling; interfacial layer; low power operation; memory cell; phase change memories; thin film; Adhesives; CMOS technology; Crystalline materials; Electrodes; Fabrication; Insulation; Phase change materials; Phase change memory; Plugs; Tunneling;

fLanguage

English

Publisher

ieee

Conference_Titel

Electron Devices Meeting, 2006. IEDM '06. International

Conference_Location

San Francisco, CA

Print_ISBN

1-4244-0438-X

Electronic_ISBN

1-4244-0439-8

Type

conf

DOI

10.1109/IEDM.2006.346908

Filename

4154327