Enhanced bias stress stability of a-InGaZnO thin film transistors by inserting an ultra-thin interfacial InGaZnO:N layer

Amorphous indium-gallium-zinc oxide (a-IGZO) thin film transistors (TFTs) having an ultra-thin nitrogenated a-IGZO (a-IGZO:N) layer sandwiched at the channel/gate dielectric interface are fabricated. It is found that the device shows enhanced bias stress stability with significantly reduced threshold voltage drift under positive gate bias stress. Based on x-ray photoelectron spectroscopy measurement, the concentration of oxygen vacancies within the a-IGZO:N layer is suppressed due to the formation of N-Ga bonds. Meanwhile, low frequency noise analysis indicates that the average trap density near the channel/dielectric interface continuously drops as the nitrogen content within the a-IGZO:N layer increases. The improved interface quality upon nitrogen doping agrees with the enhanced bias stress stability of the a-IGZO TFTs.This work was supported in part by the State Key Program for Basic Research of China under Grant Nos. 2010CB327504, 2011CB922100, and 2011CB301900; in part by the National Natural Science Foundation of China under Grant Nos. 60936004 and 11104130; in part by the Natural Science Foundation of Jiangsu Province under Grant Nos. BK2011556 and BK2011050; and in part by the Priority Academic Program Development of Jiangsu Higher Education Institutions

Holographic Superconductors with Ho\v{r}ava-Lifshitz Black Holes

We discuss the phase transition of planar black holes in Ho\v{r}ava-Lifshitz gravity by introducing a Maxwell field and a complex scalar field. We calculate the condensates of the charged operators in the dual CFTs when the mass square of the complex scalar filed is $m^2=-2/L^2$ and $m^2=0$, respectively. We compute the electrical conductivity of the \hl superconductor in the probe approximation. In particular, it is found that there exists a spike in the conductivity for the case of the operator with scaling dimension one. These results are quite similar to those in the case of Schwarzschild-AdS black holes, which demonstrates that the holographic superconductivity is a robust phenomenon associated with asymptotic AdS black holes.Comment: 12 pages, 7 figures,refs adde

Magnetic Field Effect on the Phase Transition in AdS Soliton Spacetime

We investigate the scalar perturbations in an AdS soliton background coupled to a Maxwell field via marginally stable modes. In the probe limit, we study the magnetic field effect on the holographic insulator/superconductor phase transition numerically and analytically. The condensate will be localized in a finite circular region for any finite constant magnetic field. Near the critical point, we find that there exists a simple relation among the critical chemical potential, magnetic field, the charge and mass of the scalar field. This relation indicates that the presence of the magnetic field causes the phase transition hard.Comment: 15 pages, 3 figures, 2 tables. contents improved and references adde

6-Amino-8-(2-bromo­phen­yl)-1,7,8,8a-tetrahydro-3H-isothio­chromene-5,7,7-tricarbonitrile dimethyl­formamide solvate

In the title compound, C18H13BrN4S·C3H7NO, the thio­pyran ring and the adjacent six-numbered ring adopt distorted boat conformations. The mol­ecules, lying about inversion centers, form hydrogen-bonded dimers involving one of the H atoms on the amino group with the N atom of a cyano group of an adjacent mol­ecule, resulting in a 12-membered ring system [R 2 2(12) ring motif]. The other H atom of the amino group forms an inter­molecular hydrogen bond with the O atom of the dimethyl­formamide (DMF) mol­ecule. Another lone pair of electrons on the same carbonyl O atom of DMF mol­ecule forms a non-classical C—H⋯O inter­molecular hydrogen bond, resulting in a chain of mol­ecules