Dielectric-breakdown-induced epitaxy: a universal breakdown defect in ultrathin gate dielectrics

Author

Selvarajoo, Thayalan A L ; Ranjan, Rakesh ; Pey, Kin-Leong ; Tang, Lei-Jun ; Tung, Chih Hang ; Lin, Wenhe

Author_Institution

Sch. of Electr. & Electron. Eng., Nanyang Technol. Univ., Singapore, Singapore

Volume

5

Issue

2

fYear

2005

fDate

6/1/2005 12:00:00 AM

Firstpage

190

Lastpage

197

Abstract

The breakdown phenomena in SiO_xN_y (EOT=20 Å) gate dielectric under a two- stage constant voltage stress in inversion mode are physically analyzed with the aid of transmission electron microscopy. The results show that dielectric-breakdown-induced epitaxy (DBIE) remains as one of the major failure defects responsible for gate dielectric breakdown evolution even for a stress voltage as low as 2.5 V. Based on the results, the same failure mechanism i.e., presence of DBIE would be responsible for the degradation in ultrathin gate dielectrics for gate voltage below 2.5 V. It is believed that DBIE will be present in MOSFETs failed at nominal operating voltage.

Keywords

MOSFET; dielectric thin films; electric breakdown; epitaxial layers; inversion layers; semiconductor device breakdown; transmission electron microscopy; 2.5 V; MOSFET; breakdown defect; dielectric breakdown induced epitaxy; inversion mode; transmission electron microscopy; ultrathin gate dielectrics; voltage stress; Breakdown voltage; Degradation; Dielectric breakdown; Dielectric measurements; Electric breakdown; Epitaxial growth; Failure analysis; MOSFETs; Thermal stresses; Transmission electron microscopy; Defect; dielectric-breakdown-induced epitaxy; gate dielectric;

fLanguage

English

Journal_Title

Device and Materials Reliability, IEEE Transactions on

Publisher

ieee

ISSN

1530-4388

Type

jour

DOI

10.1109/TDMR.2005.846674

Filename

1458733