Improvement of Interpoly Dielectric Characteristics by Plasma Nitridation and Oxidation for Future nand Flash Memory

Author

Ho, Ching Yuan ; Lien, Chenhsin ; Sakamoto, Y. ; Yang, Ru Jye ; Fijita, Hiro ; Liu, C.H. ; Lin, Y.M. ; Pittikoun, S. ; Aritome, S.

Author_Institution

Memory Technol. Center, Powerchip Semicond. Corp., Hsinchu

Volume

29

Issue

11

fYear

2008

Firstpage

1199

Lastpage

1202

Abstract

In this letter, plasma nitridation and oxidation on interpoly dielectric (IPD; SiO₂-SiN-SiO₂ ) for cell programming speed and reliabilities are investigated. Nitrided top oxide with N₂ plasma shows excellent physical and electrical properties in terms of edge profile on IPD and fast programming voltage. However, plasma nitridation on a floating gate suffers from data retention problems that result from nitridelike residue along the word line. A method to densify and reoxidize bottom oxide with O₂ plasma oxidation is proposed for leakage path inhibition and data retention improvement.

Keywords

dielectric materials; dielectric thin films; flash memories; logic gates; nitridation; oxidation; plasma materials processing; silicon compounds; surface treatment; IPD; N₂ plasma; NAND flash memory; SiO₂-SiN-SiO₂; cell programming speed; data retention; edge profile; electrical property; fast programming voltage; floating gate; interpoly dielectric characteristics; leakage path inhibition; nitrided top oxide; oxidation; plasma nitridation; reliability; reoxidation; Dielectrics; Nonvolatile memory; Oxidation; Plasma applications; Plasma density; Plasma devices; Plasma properties; Semiconductor films; Silicon; Voltage; Data retention; interpoly dielectric (IPD); plasma nitridation; programming speed;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2008.2004972

Filename

4655598