Title :
Plasma-induced in-line charging and damage in non-volatile memory devices
Author :
Hao Fang ; Haddad, S. ; Chi Chang ; Jih Lien
Author_Institution :
Adv. Micro Devices Inc., Sunnyvale, CA, USA
Abstract :
Plasma-induced charging in oxide/nitride/oxide (ONO) inter-dielectrics and stress damage to tunnel oxides were extensively investigated on flash memory devices. Experimental data indicated that plasma-induced in-line charging in the ONO dielectric film and tunnel oxide damage were the two mechanisms responsible for UV threshold voltage fluctuation and transconductance degradation in non-volatile memories. The degree of plasma charging in ONO dielectric and tunnel oxide increases with increasing device antenna ratios. In this paper, a physical model was successfully developed and used in explaining the observed UV threshold voltage and transconductance dependencies on device antenna ratio and stress condition. A technique of utilizing a P/sup +/-diode structure to provide effective protection against plasma-induced ONO charging and tunnel oxide stress was also demonstrated on flash memories.<>
Keywords :
CMOS memory circuits; EPROM; circuit stability; dielectric thin films; integrated circuit reliability; integrated circuit yield; sputter etching; CMOS; P/sup +/-diode structure; UV threshold voltage fluctuation; device antenna ratios; dry etch; flash memory devices; nonvolatile memory devices; oxide/nitride/oxide inter-dielectrics; plasma-induced in-line charging; stress damage; transconductance degradation; tunnel oxides; Degradation; Dielectric devices; Dielectric films; Flash memory; Fluctuations; Nonvolatile memory; Plasma devices; Stress; Threshold voltage; Transconductance;
Conference_Titel :
Electron Devices Meeting, 1994. IEDM '94. Technical Digest., International
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-2111-1
DOI :
10.1109/IEDM.1994.383367
