ZnO nanowire-array-embedded n-ZnO∕p-GaN heterojunction light-emitting diodes were fabricated by growing Mg-doped p-GaN films, ZnO nanowire arrays, and polycrystalline n-ZnO films consecutively. Electroluminescence emission having the wavelength of 386nm was observed under forward bias in the heterojunction diodes and the UV-violet light was emerged from the ZnO nanowires. The heterojunction diode was thermal treated in hydrogen ambient to increase the electron injection rate from the n-ZnO films into the ZnO nanowires. High concentration of electrons supplied from the n-ZnO films activated the radiative recombination in the ZnO nanowires, i.e., increased the light-emitting efficiency of the heterojunction diode.

Out of the blue: Light‐emitting diodes were obtained by fabricating p+‐GaN film/n‐ZnO nanowire array/n+‐ZnO film structures (see figure). Blue electroluminescence (EL) emission was observed from the nanowire‐inserted heterojunction diodes under forward bias. These diodes exhibited improved EL emission and injection current compared to those of film‐based heterojunction diodes.

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These results show that, despite the drawback of rather prolonged healing time, NPWT is an excellent therapeutic option for wounds after wide excision of melanoma on the foot, with acceptable functional and cosmetic outcomes.

We report the fabrication and characteristics of ZnO thin-film transistors (TFTs) having different channel thicknesses. The ZnO films were deposited as active channel layers on SiO 2 /p-Si substrates by rf magnetron sputtering at room temperature. Effects of the channel thickness on the structural and electrical properties of ZnO TFTs using a bottom-gate configuration were investigated. The crystalline quality and channel conductance of the ZnO films were enhanced as the channel thickness increased. The ZnO TFT with the optimized channel thickness exhibited enhancement mode characteristics with the threshold voltage of 9.9 V, the on-to-off current ratio of ∼10 5 and the field-effect mobility of 0.1 cm 2 V −1 s −1 . This research implies that ZnO TFTs produced by a simple and low-cost technique could be applicable to electronic devices.

We present a consistent overall picture of the electronic structure and ferromagnetic interaction in CaB 6 , based on our joint transport, optical, and tunneling measurements on high-quality defect-controlled single crystals. Pure CaB 6 single crystals, synthesized with 99.9999% pure boron, exhibited fully semiconducting characteristics, such as monotonic resistance for 2-300 K, a tunneling conductance gap, and an optical absorption threshold at 1.0 eV. Boron-related defects formed in CaB 6 single crystals synthesized with 99.9% pure boron induced midgap states 0.18 eV below the conduction band and extra free charge carriers, with the transport, optical, and tunneling properties substantially modified. Remarkably, no ferromagnetic signals were detected from single crystals made with 99.9999% pure boron, regardless of stoichiometry, whereas those made with 99.9% boron exhibited ferromagnetism within a finite range of carrier density. The possible surmise between the electronic state and magnetization will be discussed.

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