Enhancement of polar phases in PVDF by forming PVDF/SiC nanowire composite

Different contents of silicon carbide (SiC) nanowires were mixed with Poly(vinylidene fluoride) (PVDF) to facilitate the polar phase crystallization. It was shown that the annealing temperature and SiC content affected on the phase and crystalline structures of PVDF/SiC samples. Furthermore, the addition of SiC nanowire enhanced the transformation of non-polar α phase to polar phases and increased the relative fraction of β phase in PVDF. Due to the nucleating agent mechanism of SiC nanowires, the ion-dipole interaction between the negatively charged surface of SiC nanowires and the positive CH2 groups in PVDF facilitated the formation of polar phases in PVDF

P‐143: A Novel Current‐Scaling a‐Si:H TFTs Pixel Electrode Circuit for Active‐Matrix Organic Light‐Emitting Displays

Hydrogenated amorphous silicon thin‐film transistor (a‐Si:H TFT) pixel electrode circuit with a function of current scaling is proposed for active‐matrix organic light‐emitting displays (AM‐OLEDs). In contrast to the conventional current mirror pixel electrode circuit, in this circuit a high data‐to‐organic light‐emitting device (OLED) current ratio can be achieved, without increasing the a‐Si:H TFT size, by using a cascade structure of storage capacitors. Moreover, the proposed circuit can compensate for the variations of TFT threshold voltage. Simulation results, based on a‐Si:H TFT and OLED experimental data, showed that a data‐to‐OLED current ratio larger than 10 and a fast pixel programming time can be accomplished with the proposed circuit.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92010/1/1.2036579.pd

Magnetic Behavior of a Mixed Ising Ferrimagnetic Model in an Oscillating Magnetic Field

The magnetic behavior of a mixed Ising ferrimagnetic system on a square lattice, in which the two interpenetrating square sublattices have spins +- 1/2 and spins +-1,0, in the presence of an oscillating magnetic field has been studied with Monte Carlo techniques. The model includes nearest and next-nearest neighbor interactions, a crystal field and the oscillating external field. By studying the hysteretic response of this model to an oscillating field we found that it qualitatively reproduces the increasing of the coercive field at the compensation temperature observed in real ferrimagnets, a crucial feature for magneto-optical applications. This behavior is basically independent of the frequency of the field and the size of the system. The magnetic response of the system is related to a dynamical transition from a paramagnetic to a ferromagnetic phase and to the different temperature dependence of the relaxation times of both sublattices.Comment: 10 figures. To be published in Phys.Rev

Electrical performance and stability of tungsten indium zinc oxide thin-film transistors

Amorphous tungsten indium zinc oxide thin film transistors (WIZO TFTs) have been prepared using radio-frequency (RF) magnetron co-sputtering system to co-sputter indium zinc oxide (IZO) and indium tungsten oxide (IWO) targets. The electrical performance parameters and positive biased stress (PBS) test of the co-sputtered WIZO TFT were investigated to obtain better characteristics with regards to the IZO and IWO TFT counterparts. The co-sputtered TFT displayed high electrical performance (field effect mobility, µFE ∼ 22.30 cm2/Vs, and sub-threshold swing, SS ∼ 0.36 V/decade) and stable electrical behavior (PBS value shift, ΔVth ∼ 1.23 V) than the IZO (µFE ∼ 19.90 cm2/Vs, SS ∼ 0.46 V/decade, ΔVth ∼ 7.79 V) and IWO (conducting in nature) TFTs for its application in flexible and transparent displays.Accepted versio