Ultrathin gate oxide reliability: physical models, statistics, and characterization

Abstract

Abstract-The present understanding of wear-out and breakdown in ultrathin ( 5 0 nm) SiO 2 gate dielectric films and issues relating to reliability projection are reviewed in this article. Recent evidence supporting a voltage-driven model for defect generation and breakdown, where energetic tunneling electrons induce defect generation and breakdown will be discussed. The concept of a critical number of defects required to cause breakdown and percolation theory will be used to describe the observed statistical failure distributions for ultrathin gate dielectric breakdown. Recent observations of a voltage dependent voltage acceleration parameter and non-Arrhenius temperature dependence will be presented. The current understanding of soft breakdown will be discussed and proposed techniques for detecting breakdown presented. Finally, the implications of soft breakdown on circuit functionality and the applicability of applying current reliability characterization and analysis techniques to project the reliability of future alternative gate dielectrics will be discussed.

A 0.5 V 65.7 dB 1 MHz continuous-time complex delta sigma modulator

“…Operation with strongly reduced supply voltages is necessary to maintain the device reliability. As reported in [3,4], for nanoscale devices with ultra-thin gate-oxide the lifetime degrades exponentially with the supply voltage, rather than with the electric field across the oxide layer. The increasing power density is also a limiting factor in nanoscale technologies, and for digital integrated circuits, the reduction of the supply voltage leads to a significant reduction of the dynamic power consumption and power density [5].…”

On the stochastic nature of resistive switching in Cu doped Ge0.3Se0.7 based memory devices

“…In the literature, breakdown analysis is commonly used as a unique tool to investigate the scaling effects on device reliability and performance. [20][21][22][23][24] Hence, not only to verify the compatibility of the proposed nucleation model, but also from the device reliability point of view, it becomes important to investigate the thickness and area dependencies of the t BD probability distributions on Cu doped Ge 0.3 Se 0.7 solid electrolyte based memory devices. Figure 7(a) shows Weibull plots of the cumulative t BD probability distributions for Ge 0.3 Se 0.7 films with thicknesses ranging from 30 to 120 nm.…”

“…[20][21][22][23][24] When measuring the breakdown fields in dynamic tests or the "time-to-breakdown" in static tests, a statistical distribution is generally found. The breakdown statistics are usually related in some way to underlying random microscopic physical processes.…”

Spatially resolved observation of uniform precession modes in spin-valve systems

“…In the literature, breakdown analysis is commonly used as a unique tool to investigate the scaling effects on device reliability and performance. [20][21][22][23][24] Hence, not only to verify the compatibility of the proposed nucleation model, but also from the device reliability point of view, it becomes important to investigate the thickness and area dependencies of the t BD probability distributions on Cu doped Ge 0.3 Se 0.7 solid electrolyte based memory devices. Figure 7(a) shows Weibull plots of the cumulative t BD probability distributions for Ge 0.3 Se 0.7 films with thicknesses ranging from 30 to 120 nm.…”

“…[20][21][22][23][24] When measuring the breakdown fields in dynamic tests or the "time-to-breakdown" in static tests, a statistical distribution is generally found. The breakdown statistics are usually related in some way to underlying random microscopic physical processes.…”