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We demonstrated that manganese (Mn)-doped GaN nanowires (NWs) exhibit p-type characteristics using current–voltage (I–V) characteristics in both heterojunction p–n structures (GaN:Mn NWs/n-Si substrate) and p–p structures (GaN:Mn NWs/p-Si). The heterojunction p–n diodes were formed by the coupling of the Mn-doped GaN NWs with an n-Si substrate by means of an alternating current (AC) dielectrophoresis-assisted assembly deposition technique. The GaN:Mn NWs/n-Si diode showed a clear current-rectifying behavior with a forward voltage drop of 2.4 V to 2.8 V, an ideality factor of 30 to 37, and a parasitic resistance in the range of 93 kΩ to 130 kΩ. On the other hand, we observed that other heterojunction structures (GaN:Mn NWs/p-Si) showed no rectifying behaviors as seen in p–p junction structures.

We report on the current transport mechanism in Au/GaN nanowire–Schottky diodes at high temperature using current–voltage characterization in the temperature range of 300–573 K. We observed that the ideality factor for the GaN nano-Schottky diodes decreased from 11.2 at 323 K and reached its lowest value of 7.9 at 500 K. Then, it started to increase with increasing temperatures up to 573 K. On the other hand, the Schottky barrier height increased throughout all of the temperature ranges up to 573 K. We found that the abnormal behaviors of the barrier heights and the ideality factors in the current transport by varying the temperature of 300–500 K can be well explained by a combination of the thermionic field emission (TFE) mechanism and a model with a Gaussian distribution of the barrier heights that were predominant at the interface between the Schottky metal (Au) and the semiconductor (GaN nanowire). We also suggested that the increase of the ideality factor at a temperature higher than 500 K could be attributed to a trap-assisted tunneling current in a TFE mechanism.

We report on the electrical characteristics and the effects of source/drain Schottky barrier heights (SBHs) in a lightly implanted silicon nanowire field-effect transistor (SiNW FET). We prepared the SiNW FETs by boron implantation with a dose of 1×1012 ions/cm2 and an energy of 10 keV. Our results indicated that the nature of the metal-contacts on the source/drain electrodes had a significant impact on the current–voltage characteristics for B-implanted SiNW FETs. The current–voltage ( I D – V D S ) characteristics for the B-implanted SiNW FETs with a symmetric IV behavior exhibited a clear p-channel FET behavior with a field-effect mobility of ∼0.4 cm2/V s and a hole concentration of ∼1.7×1017 cm−3. A 2D ATLAS simulation (SILVACO Inc.) with two different Schottky barrier heights of source/drain contacts to the SiNW supported the experimental results well.

We report on the dielectrophoresis (DEP) characterization of single crystalline zinc oxide (ZnO) nanowires with variations of the AC electric field and frequency. The alignment yield rate of ZnO nanowires in the gap over the 200 metal electrodes increased with increasing AC electric field and also changed by the applying frequency. Moreover, we demonstrated that the DEP prepared multi-ZnO nanowires field-effect transistors (FETs) exhibited excellent performance with a transconductance of ∼3 μS and a high drain current of ∼2.7 × 10−6 A (VDS = 5 V, VG = 20 V).

We report on the fabrication and characterization of Ti/Au Ohmic contacts to unintentionally doped gallium nitride (n-GaN) nanowires. The specific contact resistance and resistivity were determined to be ~1.1 × 10−5 ± 5 × 10−6 Ω cm2 and ~6.9 × 10−3 ± 3 × 10−4 Ω cm, respectively, with a diameter of ~140 nm using a transmission line model (TLM). We also present the electrical characterizations of metal/GaN nano-Schottky diodes with four Schottky metals (Al, Ti, Cr and Au) on unintentionally doped GaN nanowires using current–voltage (I–V) characteristics at room temperature. We observed the abnormal electrical characteristics of GaN nano-Schottky diodes for each Schottky metal.