A relationship between statistical time to breakdown distributions and pre-breakdown negative differential resistance at nanometric scale

Abstract

Using an ultra-high vacuum Conductive atomic force microscopy (C-AFM) current voltage, pre-breakdown negative differential resistance (NDR) characteristics are measured together with the time dependent dielectric breakdown (TDDB) distributions of Si/SiON (1.4 and 2.6 nm thick). Those experimental characteristics are systematically compared. The NDR effect is modelled by a conductive filament growth. It is showed that the Weibull TDDB statistic distribution scale factor is proportional to the growth rate of an individual filament and then has the same dependence on the electric field. The proportionality factor is a power law of the ratio between the surfaces of the CAFM tip and the filament's top. Moreover, it was found that, for the high fields used in those experiments, the TDDB acceleration factor as the growth rate characteristic is proportional to the Zener tunnelling probability. Those observations are discussed in the framework of possible breakdown or forming mechanism.

Influence of dielectric layer thickness on charge injection, accumulation and transport phenomena in thin silicon oxynitride layers: a nanoscale study

“…To go further in the description of charge dynamic during injection, the study on charge injection and surface potential measurements was completed with C-AFM measurements. The C-AFM measurements were performed by using the second device structure (figure 1(b)) and a diamond With respect to the current measurements, one can say that Fowler-Nordheim conduction is most likely the mechanism controlling the current in ultrathin layers [23,25,27,28]. However, for the interpretation of these results, in term of transport laws, the current density needs to be computed, which requires estimation of the current collection area.…”

Nanoscale Characterization of High-K/IL Gate Stack TDDB Distributions After High-Field Prestress Pulses

“…C-AFM measurements were performed at room temperature with an Omicron AFM/scanning tunneling microscopy system under UHV (≤109 Torr) with conductive diamond tips (B doped). The AFM tip was used as a grounded top electrode (tip area = 5nm 2 [14]), and a negative voltage was applied to the substrate. By convention, all of the current-voltage characteristics are presented according to a positive gate voltage.…”

“…The tip/sample contact area determined by fitting the tunneling current as a function of voltage was 5 nm 2 . Due to this small contact area, the tunneling current is lower than at device scale providing new insights in pre breakdown current characteristics [13], [14]. The comparison of tests at device scale with studies carried out at nanometric scale using the conductive tip of an atomic force microscope (C-AFM) as upper electrode [15] shows that even at this area range, the cumulative failure probability of monolayer gate oxides presents a Weibull behavior.…”

Emerging Scanning Probe–Based Setups for Advanced Nanoelectronic Research

“…In its origin CAFM, was mainly used to characterize the electrical properties of thin (<50 nm) dielectric materials (i.e., SiO 2 , HfO 2 , Al 2 O 3 ) at nanoscale. More specifically, the CAFM can be used to study tunneling current, polycrystallization, charge trapping and de‐trapping, random telegraph noise, stress induced leakage current (SILC), dielectric breakdown, and resistive switching . Recently, its use has also expanded to other low‐dimensional materials, such as nanowires (NWs), carbon nanotubes (CNT), nanodots, and 2D materials .…”