Overerase phenomena: an insight into flash memory reliability

Author

Chimenton, Andrea ; Pellati, Paolo ; Olivo, Piero

Author_Institution

Dipt. di Ingegneria, Univ. of Ferrara, Italy

Volume

91

Issue

4

fYear

2003

fDate

4/1/2003 12:00:00 AM

Firstpage

617

Lastpage

626

Abstract

The most important reliability issues related to the erasing operation in flash memories are, still today, caused by single bit failures. In particular, the overerase of tail and fast bits affects the threshold voltage distribution width, causing bit-line leakage that produces read/verify circuitry malfunctions, affects the programming efficiency due to voltage drop, and causes charge-pump circuitry failure. This brief overview explores the most important characteristics of these anomalous bits, their relation with the erratic erase phenomena and their impact on flash memory reliability. Identification techniques, experimental results, and physical models are also discussed.

Keywords

failure analysis; flash memories; integrated circuit modelling; integrated circuit reliability; voltage distribution; bit-line leakage; charge-pump circuitry failure; erasing operation; erratic erase phenomena; flash memory reliability; identification techniques; overerase phenomena; overview; physical models; programming efficiency; read/verify circuitry malfunctions; single bit failures; threshold voltage distribution width; voltage drop; Flash memory; Integrated circuit reliability; Integrated circuit technology; Nonvolatile memory; Probability distribution; Semiconductor device reliability; Semiconductor memory; Stress; Tail; Threshold voltage;

fLanguage

English

Journal_Title

Proceedings of the IEEE

Publisher

ieee

ISSN

0018-9219

Type

jour

DOI

10.1109/JPROC.2003.811713

Filename

1199088