Time Dependent Dielectric Breakdown of Thin Silicon Oxide Using Dense Contact Electrification

Abstract

We achieved time dependent dielectric breakdown (TDDB) measurement of a thin silicon oxide microscopically using contact electrification. By increasing the external bias voltage, TDDBs of the oxide layer without and with oxide surface roughening were observed sequentially. Charge-to-breakdown in the contact electrification was estimated to be on the order of 10-5∼10-6 C/cm2. This value is higher than that of electrified charge density in the absence of external bias voltage, but is much smaller than the value of ∼5×10-1 C/cm2 obtained in the conventional TDDB measurement using a metal-oxide-semiconductor (MOS) capacitor. From calculation of the number of injected charges per atom, TDDB measurement using contact electrification is expected to provide a more quantitative evaluation of charge-to-breakdown than that using a MOS capacitor.

Charge writing in silicon–silicon dioxide for nano-assembly

“…Morita et al [11] described microscopic contact charging and dissipation of silicon dioxide with an AFM tip. In a subsequent paper [12], the dielectric breakdown due to contact electrification was investigated. Their experiments showed that with the passage of time, a dip in the profile of the electrostatic force on the charged AFM tip is observed.…”

Can charge writing aid nanotechnological manipulation?

“…However, charge writing using AFMs and contact electrification has been quite successful, and its mechanisms extensively studied [36][37][38][39].…”

Analysis of Local Breakdown Process in Stressed Gate SiO2 Films by Conductive Atomic Force Microscopy

“…In order to understand the local degradation phenomena, the nanometer-scale observation of thin gate dielectric films by conductive atomic force microscopy (C-AFM) has attracted much attention in recent years. [12][13][14][15][16][17] C-AFM is a powerful tool for studying local phenomena in thin gate dielectric films, because it can detect leakage current with a nanometer-scale spatial resolution. In addition, C-AFM allows us to evaluate current leakage properties quantitatively on the basis of energy band diagrams because the metal-coated tip/oxide/silicon substrate structure can be regarded as a MOS capacitor.…”

“…These studies suggest that a wear-out failure of actual MOS devices is attributable to local degradation phenomena. As a unique method, Fukano et al 16) proposed a technique of estimating charges necessary for the breakdown by observing the change in electrified charges that are provided from metal-coated tips and quantitatively compared them with those obtained using a MOS capacitor. However, the relationship between nanometer-scale phenomena observed by C-AFM, such as local leakage current and their distributions, and the degradation properties of the MOS devices has been examined to date.…”