Impact of time dependent dielectric breakdown and stress induced leakage current on the reliability of (Ba,Sr)TiO/sub 3/ thin film capacitors for Gbit-scale DRAMs

Author

Yamamichi, S. ; Yamaichi, A. ; Park, D. ; Hu, C.

Author_Institution

Fundamental Res. Labs., NEC Corp., Kawasaki, Japan

fYear

1997

fDate

10-10 Dec. 1997

Firstpage

261

Lastpage

264

Abstract

Time dependent dielectric breakdown (TDDB) and stress-induced leakage current (SILC) are investigated for the reliability of (Ba/sub 0.5/Sr/sub 0.5/)TiO/sub 3/ (BST) thin films. TDDB characteristics show a lifetime longer than 10 years at +1 V for BST films with an SiO/sub 2/ equivalent thickness (t/sub eq/) of 0.70 nm. The breakdown is strongly affected by leakage current properties, and does not depend on the dielectric constant. SILC is studied at +1V in time domain after stress charge injection into BST films. 10 year operation for Gbit-scale DRAMs can be guaranteed in spite of the charge loss caused by SILC.

Keywords

DRAM chips; barium compounds; electric breakdown; leakage currents; reliability; strontium compounds; thin film capacitors; (Ba,Sr)TiO/sub 3/ thin film capacitor; (Ba/sub 0.5/Sr/sub 0.5/)TiO/sub 3/; 0.70 nm; 1 V; 10 year; DRAM; SiO/sub 2/ equivalent thickness; charge injection; dielectric constant; lifetime; reliability; stress induced leakage current; time dependent dielectric breakdown; Binary search trees; Breakdown voltage; Capacitors; Dielectric breakdown; Dielectric thin films; Electric breakdown; Leakage current; Random access memory; Sputtering; Stress;

fLanguage

English

Publisher

ieee

Conference_Titel

Electron Devices Meeting, 1997. IEDM '97. Technical Digest., International

Conference_Location

Washington, DC, USA

ISSN

0163-1918

Print_ISBN

0-7803-4100-7

Type

conf

DOI

10.1109/IEDM.1997.650377

Filename

650377