The energy level, density and attempt to escape frequency of carrier traps in an Si3N4 film in tunnel oxide/nitride/oxide (ONO) multilayer for metal/oxide/nitride/oxide/silicon (MONOS) nonvolatile memory are investigated by discharging current transient spectroscopy (DCTS). To analyze the electrical properties of carrier traps observed through DCTS, a new model including the tunneling probability of the tunnel oxide film between the Si3N4 film and an Si substrate was proposed. As a result, the electron traps in the Si3N4 film, which are assumed to be related to the threshold voltage decay, i.e. data retention, were found for the first time. The energy level of the electron traps in the Si3N4 film in the ONO multilayer was 0.8–0.9 eV from the conduction band and the density was 1–5×1018 cm-3. The attempt to escape frequency of 2×1014 s-1 was also obtained. The energy level of the hole traps and its density were 0.8–0.9 eV from the top of the valence band and 1–4×1018 cm-3, respectively. The magnitude of the trap density obtained from DCTS shows good agreement with that obtained from memory hysteresis characteristics. These results indicate that their carrier traps are amphoteric traps.

for a 'hairpin' emission system values of various other emission systems.Spherical aberration coefficient and source diameter have been measured Both have been found to be smaller than the corresponding N connection with some recent ray-tracing measurements in electron spectrometers, we have investigated the spherical aberration of a ' hairpin ' emission system which served as a ' point ' source in these experiments.Hairpin systems are now widely used in many electronic devices, for example in electron microscopes, electron diffraction cameras and x-ray point-focus tubes, hence the results of our measurements might be of some interest.The measuring arrangement is shown in Figure 1. There, C represents a hairpin-shaped tungsten-molybdenum wire of 0.08 mm. thickness, G is a grid

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We performed modeling and simulations of polysilicon–oxide–nitride–oxide–semiconductor (SONOS) memory devices with traps for charge accumulation. Comparisons of the dependence of writing and erasing characteristics on the tunnel-SiO2-layer thickness and SiN x -layer thickness were made. Simulated results of erasing characteristics are in good agreement with the experimental results, but simulated results of writing characteristics are not. Moreover, we simulated the dependence of writing and erasing characteristics on the distribution of the trap density in the SiN x layer, the dependence of writing characteristics on the doping density of polysilicon for the gate, and the dependence of the injection current and leakage current on the gate pulse duration.