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Financial risk tolerance refers to the amount of risk a person is willing to take when making financial decisions. Previous researchers have found that demographic factors when used as independent variables to have an effect on the risk tolerance behavior of investors. Within this study, emphasis was given to gender and age within a sample of South African investors. Not much research on risk tolerance and demographics has been done in South Africa. Hence, an opportunity for further research within this field emerged. This study aimed to contribute towards the accurate risk profiling of South African investors based on their level of risk tolerance considering their gender and age. This study can be used as a future forecasting tool for investment companies to predict risk tolerance levels based on gender and age levels. Results from this study correspond to previous studies where male investors are more risk tolerant than female investors. A statistical difference was also found between male and female investors within the age categories of 35-49 years and investors older than 50 years. All age categories were found to be more risk tolerant for investors older than 50 years based on the binary regression.

In this work, a compact mathematical representation of the time-dependent breakdown dynamics of heavy-ion irradiated thin oxides subjected to electrical stress is investigated. The model is formulated as a stochastic differential equation for the gate leakage current and consists of one deterministic term and two random terms. The first one deals with the short transient and evolution toward the steady-state conduction level after the triggering of a breakdown event, the second term simulates the noisy behavior of the current between the arrival of events, and the third term represents the opening of successive breakdown paths across the dielectric film. Ion hits are assumed to cause a finite number of latent damaged sites distributed throughout the oxide area, which manifest, as the electrical stress proceeds, in the long-run saturating behavior of the current-time characteristics. A nonhomogeneous Poisson counting process is used to describe the switching from latent to active spot, whereas a Gaussian process is considered for the low-level fluctuations. Index Terms--Degradation, metal-oxide semiconductor (MOS), reliability, time-dependent dielectric breakdown (TDDB), ultrathin oxide.

The prospective behavior of the nanoscale double-gate metal-oxide-semiconductor field-effect-transistor (DG-MOSFET) when used as the basis for building analog circuits is explored. It is reported that the transconductance efficiency is not too much affected by length scaling and temperature.

The experimental evidence on the voltage-dependence of the voltage acceleration factors on ultrathin oxides from 5nm down to ~ 1 nm over a wide range of voltages from ~2V to 6V is described. The area scaling method and long-term stress method is used for the investigation of the phenomenon.

Weibull slopes as a function of thickness, voltage and temperature are determined. The validity of the stress-induced leakage current measurement as an experimental means to measure the critical defect density is discussed.

Complementary resistive switching (CRS) arises when two bipolar-mode memristive devices are antiserially connected, forming a single functional structure. The combined effect of both memristors leads to the appearance of high (HRS) and low (LRS) resistance windows in the current–voltage (${I}$ – $V$) characteristic that finds application in fields such as neuromorphic computing and logic circuits. In this work, the electric behavior of HfO2-based CRS devices intentionally fabricated with a common central electrode is investigated both from experimental and modeling viewpoints. Experiments reveal that the maximum voltage applied to the structure allows tuning the amplitude of the resistance window following a self-balance dynamics. The origin of the abrupt (digital) and gradual (analog) transitions between the HRS and LRS states is elucidated through the inclusion of the snapback and snapforward effects in the switching dynamics. The ${I}$ – ${V}$ characteristics of the CRS devices are compact modeled with two opposite-biased memdiodes and simulated in LTSpice using an equivalent three-terminal subcircuit. It is shown that the proposed model is able to reproduce with a high degree of accuracy not only the observed CRS behavior for HfO2 but also the main features exhibited by devices with a wide variety of oxide/electrode materials. [ABSTRACT FROM AUTHOR]

The influence of spacer layer width and asymmetry on the simulation of quantum transport in resonant tunneling diodes was investigated. Findings revealed that these layers have substantial effects on the I-V characteristic, which present significant differences under direct or reverse bias polarity in devices with asymmetric spacer layers. These differences can be viewed in terms of potential profile comparisons of the simulated structures and are in qualitative agreement with experimental data.

An analysis of the trapped charge distributions of thin silicon oxide films subjected to static and dynamic stresses was presented. Voltages with different values and polarities were constantly applied to the thin films. Results revealed that trap generation rates of DC stresses were independent to stress polarity and the breakdown time for negative stress voltages was much shorter. Thus, the a smaller density of traps was needed to stimulate a final breakdown current runaway of thin silicon oxide films.

Post-breakdown conduction in polycrystalline-silicon and metal-grated thin-oxide metal-oxide-semiconductor capacitors was investigated. The results showed that several breakdown events could be produced in one capacitor during constant voltage stress due to the extreme localization of the breakdown. The observed reversibility of the breakdown was further evidenced by the bistable conduction in the post-breakdown current-voltage characteristic.