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We have developed a carbon nanostructure, which is comprised of high-density carbon nanotips on a graphite layer. These carbon nanotips, with tip diameters of ∼10 nm, are grown by high-density plasma chemical vapor deposition onto Ni-coated Si using an inductively coupled plasma. The Ni on Si changes into NiSi2 by substrate heating. First, a carbon buffer layer and then a graphene sheet are formed on the NiSi2. Then, the carbon nanotips are grown by a C2H2/H2 plasma on the graphene sheet. The carbon nanotips show good adhesion to the substrate and are almost aligned, with an average length of 110 nm. They exhibit a turn-on field of 0.1 V/μm, a field amplification factor of ∼13 000, a current density of 2 mA/cm2 at a field of 2 V/μm, and uniform electron emission.

We report high-performance homojunction amorphous-indium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) with low-resistive a-IGZO source/drain (S/D) electrodes. The a-IGZO S/D electrodes are selectively treated with high-power NF 3 plasma, which reduces their resistivity from ∼16 to 5.5×10 −3 · cm. X-ray photoelectron spectroscopy indicates an increase in weakly bonded oxygen and a substantial amount of indium-fluorine and zinc-fluorine bonds at the a-IGZO top surface (extending to ∼7 nm into the bulk) after plasma treatment. Temperature-dependent conductivity measurements show metallic behavior of the a-IGZO after treatment. It is concluded that fluorine atoms substitute for oxygen atoms-generating free electrons in the process and/or occupy oxygen vacancy sites-eliminating electron trap sites. As a result, the homojunction TFTs show good ON-state characteristics with typical field-effect mobility, subthreshold gate-voltage swing, and turn-ON voltage of 19 ± 1 cm 2 /V · s, 178 ± 30 mV/decade, and −3.2 ± 1.5 V, respectively. Good stability at high temperature and under bias and light stress are also exhibited by the homojunction TFTs, verifying a stable doping effect by the NF 3 plasma treatment. IndexTerms-Amorphous-indium-gallium-zinc-oxide (a-IGZO), fluorine, homojunction, thin-film transistor (TFT).

In this study, we prepared biocompatible, water-soluble, superparamagnetic, manganese-doped, magnetism-engineered iron oxide (MnMEIO) nanocrystals with reactive moieties. This was achieved via a one-pot synthesis protocol by thermally decomposing metal acetylacetonate precursors in 2-pyrrolidone in the presence of polyethylene glycol diacid. Using carbodiimide, we achieved nanocrystals coupled with 9-aminoacridine and folic acid through 2,2 0 -(ethylenedioxy)bis-ethylamine. The results suggest that the nanocrystals provide carboxyl functional groups as binding sites. Their surface modification and composition were analyzed by Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS), respectively. Using Mo¨ssbauer spectroscopy and a magnetometer, we have shown that these nanocrystals exhibit superparamagnetic behaviors. In addition, we have demonstrated that the nanocrystals were not significantly toxic, and hence are biocompatible.