Search

[Display omitted] • Gd-doped ZnO films were synthesized by sol–gel spin coating technique. • Anomalous Hall Effect signal reveals intrinsic ferromagnetism and existence spin polarization in Gd-doped ZnO films. • MFM qualitatively proves the existence of spin polarization in the Gd-doped ZnO films. • Optical band-gap results indicate the existence of strong spin-exchange interaction. In this study, Gd-doped ZnO films with different Gd concentrations were synthesized by sol–gel spin coating technique. The intrinsic ferromagnetism and the existence of spin-polarized carriers in Gd-doped ZnO films were investigated using Hall effect and MFM. The Hall effect and MFM measurement detect the AHE signal and the magnetic domain structure, respectively, proving intrinsic FM and the existence the spin polarization in the films. XRD and FTIR analysis showed that the crystal structure of Gd-doped ZnO films is a hexagonal wurtzite structure. The optical band gap is found red-shifted from 3.265 to 3.227 eV with the increase in Gd doping concentration, indicating the existence of strong spin-exchange interaction. EDX analysis confirmed the presence of Gd in the ZnO matrix. Based on the finding, we proposed 8 at. % Gd-doped ZnO film is optimal, potentially used as a spin injector for organic spintronic devices. [ABSTRACT FROM AUTHOR]

Abstract: SrTiO3 thin films were deposited on AlGaN/GaN wafer by a simple, low-temperature liquid-phase deposition (LPD) method, and applied as the gate dielectric in metal oxide semiconductor high electron mobility transistor (MOSHEMT). X-ray diffraction and electrical characteristics were measured to investigate the film phase and leakage current. AlGaN/GaN MOSHEMTs with 20nm-thick SrTiO3 as the gate dielectric were also fabricated. Compared with its counterpart HEMT, MOSHEMT shows lower leakage current and larger breakdown voltage. The suppressed gate leakage current improves both I on/I off ratio and subthreshold slope. Larger maximum drain current density could be achieved with higher V on in the MOSHEMT. Flatter transconductance and wider gate voltage swing of the MOSHEMT demonstrate better device linearity. The lower low-frequency noise is obtained due to the lower surface states. [Copyright &y& Elsevier]

Abstract: InGaP/InGaAs metal–oxide–semiconductor (MOS) pseudomorphic high-electron-mobility transistor (PHEMT) with a nanoscale liquid phase-oxidized InGaP as the gate dielectric is demonstrated. Not only does the MOS-PHEMT have the advantages of the MOS structure, but it also has high-carrier density and a high-mobility 2DEG channel. Using selective oxidation of InGaP by liquid phase oxidation, the MOS-PHEMT can be fabricated without additional recess processes. The MOS-PHEMT exhibits larger transconductance, lower gate leakage current, higher breakdown voltage, higher cut-off frequency, lower minimum noise figure, and higher power-added efficiency than does its counterpart (reference PHEMT). The interface roughness effect on the DC and RF performance of devices is also discussed. [Copyright &y& Elsevier]

• There is interaction between neutron and electron phenomenon. • Increase radiation time give longer interaction of neutron-electron. • Concentration of Ti3+ and V o increase by increasing the radiation time. • Defect development can be create by neutron beam treatment. • Orbital shifted toward nucleus phenomenon has been discovered. Influence of the interaction between neutron and TiO 2 surface is studied for the first time. By knowing the mechanism of this interaction, it could be useful to understand the possibility of the formation of Ti3+ and oxygen vacancy (V o) surface defect. Raman spectroscopy and X-ray Photoelectron Spectroscopy (XPS) were used for surface defect characterization analysis. According to XPS analysis, it shows that binding energy is shifted about 0.05 eV toward higher binding energy. The formation of Ti3+ and V o defect is depending on the irradiation time which explained that longer irradiation time would give more time to neutron-electron interaction, thus enhanced the defect development on TiO 2 thin film. [ABSTRACT FROM AUTHOR]