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The tapered channel effect is a major concern in three-dimensional (3-D) NAND technology because the effect causes differences in the electrical characteristics, including the threshold voltage (VT), between the upper and the lower cells. We simulated the tapered channel effect by using Sentaurus technology, computer-aided design (TCAD) tools, and based on the results, we propose a novel method to lessen the non-uniformity of the threshold voltage shift ( ${\Delta }\text{V}_{\mathrm{ T}}$ ) between the cells. The difference in ${\Delta }\text{V}_{\mathrm{ T}}$ between the upper and the lower cells due to the tapered channel can be reduced by employing a tapered blocking oxide layer with a proper taper angle. These results will be helpful in designing reliable 3-D NAND flash memories.

We report a water-resistive and wearable triboelectric nanogenerator on a polyurethane/polyester textile substrate with a planarization layer. The power generation and reliability of the triboelectric nanogenerators (TENGs) fabricated utilizing a resin planarization layer were significantly enhanced in comparison with those of TENGs without the resin planarization layer. The planarization layer was deposited on the polyurethane/polyester textile substrate by using spin coating and ultraviolet curing to improve its surface properties and polarity. The output voltages and currents of TENGs based on a resin planarization layer on a polyurethane/polyester substrate were measured in the vertical contact-separation mode by using a counter unit containing Al electrodes and a polyimide friction layer. The TENGs exhibited a peak potential of over 30 V, which is about three times larger than that of the devices without such a planarization layer, and the corresponding maximum power density was 3.16 mW/m2. Furthermore, the results of endurance and water resistance tests carried out on the TENGs with a resin planarization layer on a textile substrate showed that such devices were suitable for use in applications in which the device must be worn.

In [1], the following sentence on p. 774, second column, is revised as follows.

Post-growth rapid thermal annealing (RTA) has been used to investigate an interdiffusion and the structural change in an InGaAs dots-in-a-well (DWELL) structure grown by molecular beam epitaxy using an alternately supplying InAs and GaAs sources. In the case of the as-grown sample, which has a metastable quantum structure due to an intentional deficit of source materials, it is found that an InGaAs quantum well (QW) coexists with the premature quantum dots (QDs), and an intermediate layer exists between the QW and the QDs. Through the RTA process at 600 and 800 °C for 30 s, metastable structure changes into a normal DWELL structure composed of QDs and QW as a result of the intermixing of premature QDs and the intermediate layer. [ABSTRACT FROM AUTHOR]

We investigated the electrical and optical properties of InGaAs self-assembled quantum dots grown using the atomic layer epitaxy (ALE) technique. Dots–in–a–well structures were grown by alternately supplying InAs and GaAs sources on an InGaAs layer and covering with another InGaAs layer. Three samples produced with different numbers of cycles of alternate InAs/GaAs supply were characterized by capacitance-voltage and photoluminescence (PL) measurements. For the ten cycle dots–in–a–well structure, a strong zero-dimensional electron confinement was observed even at room temperature. On the other hand, for the five-cycle structure, the PL results indicate that the InGaAs quantum well structure coexists unstably with premature quantum dots. By comparing the results for samples with different numbers of cycles, we suggest that an ALE dots–in–a–well structure can be formed by the aggregation of In and Ga atoms incorporated into the InGaAs quantum well layer when the number of cycles exceeds the critical number of seven cycles. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The electron areal density and carrier mobility is modeled in a two-dimensional electron gas layer developed in a [delta]-doped AlInSb/InSb heterostrucutre. The dependencies of the electron areal density on temperature, spacer layer thickness, doping density and the quantum well thickness are calculated, as they have important implications for extraordinary magnetoresistance (EMR) sensor design.

Organic light-emitting devices (OLEDs) were fabricated utilizing Au-ZnO nanocomposites (NCs) with various Au nanoparticles (NPs) concentrations synthesized by using a sol-gel process to enhance their current efficiency, and these devices were compared with OLEDs fabricated utilizing ZnO NPs only. The electroluminescence intensity of the OLEDs with Au-ZnO NCs at a wavelength of 535 nm was significantly larger than that of the OLEDs with ZnO NPs by a factor of 1.89. The current efficiency of the OLEDs with 10 wt. % Au-ZnO NCs at 1000 cd/m² was higher by 16.7 cd/A than that of the OLEDs with ZnO NPs. This increase in the current efficiency of the OLEDs with Au-ZnO NCs was attributed to an enhancement of the out-coupling efficiency due to the existence of the localized surface plasmonic resonance effect induced by the Au NPs that were embedded in the Au-ZnO NCs. [ABSTRACT FROM AUTHOR]

The authors successfully obtained high quality ZnO thin films by growing them at room temperature (RT) and postannealing by rapid thermal annealing (RTA). The thin films were grown by pulsed laser deposition on Si (100) substrates at RT, and RTA was performed under various temperatures and ambient conditions. Based on the UV emission to visible emission ratio in RT photoluminescence (PL) spectra, the optimum film was obtained at annealing temperature ∼700 °C in an ambient of Ar, N2, or O2 at 0.1 Torr, while the optimum annealing temperature was above 1100 °C in the air ambient at atmospheric pressure. The morphology and structure of the films in different RTA conditions were investigated by using field emission scanning electron microscopy and grazing incidence x-ray diffraction, and were discussed in conjunction with the PL data. [ABSTRACT FROM AUTHOR]

CdSe/CdS core–shell quantum dots (QDs) were synthesized using a facile method in aqueous phase. X-ray diffraction pattern, high-resolution transmission electron microscopy images, and energy dispersive spectroscopy profiles showed that stoichiometric CdSe/CdS QDs were formed. Temperature-dependent photoluminescence spectra showed that the activation energy of CdSe/CdS core–shell QDs was 15 meV. The potential profiles and interband transition energies of the strained type-II CdSe/CdS core–shell QDs were calculated. The calculated interband transition energies slightly decreased from 2.061 to 2.007 eV when the shell thickness increased from 10 to 17 Å. The theoretical interband transition energy of 2.007 eV was in reasonable agreement with the photoluminescence excitonic transition energy of 1.98 eV. [ABSTRACT FROM AUTHOR]