Interpoly Oxide Related Fast Bit Failures in the Himos ™ Flash Memory Cell

Author

Ackaert, J. ; Yao, T. ; Lowe, A. ; Gassot, P. ; Ooghe, W. ; Schlegel, L. ; Bogaert, P. ; Branquart, H.

Author_Institution

AMI-Semicond. Belgium BVBA, Oudenaarde

fYear

2006

fDate

1-4 May 2006

Firstpage

1

Lastpage

5

Abstract

A new data retention failure of the HIMOStrade cell is shown in this paper. The characterization of the failing bit reveals several differences with usual moving bits: the floating gate charge leaks through the interpoly dielectric. Investigations on the process suggest local damage of the interpoly oxide due to exposure to the erase junction implant. The issue is caused by notching of the erase junction implant mask allowing this implant to degrade the interpoly oxide. The issue is solved by the introduction of a bottom anti reflective coating layer, preventing this notching resulting is a significant increase of the yield and the processing window

Keywords

dielectric materials; failure analysis; flash memories; HIMOS; antireflective coating layer; data retention failure; erase junction implant mask; fast bit failures; flash memory cell; floating gate charge; interpoly dielectric; interpoly oxide; Character generation; Coatings; Degradation; Dielectrics; Flash memory cells; Implants; Nonvolatile memory; Temperature; Testing; Threshold voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Integrated Circuit Design and Technology, 2006. ICICDT '06. 2006 IEEE International Conference on

Conference_Location

Padova

Print_ISBN

1-4244-0097-X

Type

conf

DOI

10.1109/ICICDT.2006.220784

Filename

1669371