Effect of Defect Bands on the Electrical Characteristics of Irradiated GaAs and
Proton bombarded p-Si and neutron irradiated n-GaAs have been studied by DLTS, current±voltage, and capacitance±voltage measurements in metal±semiconductor junctions. The junctions were prepared by evaporation of Al onto silicon and of gold onto GaAs. Both junctions exhibited defect bands after bombardment. The bombardment has shifted the Fermi-level pinning position, increased the ideality factor in both junctions, and also affected the temperature dependence of the ideality factor and that of the capacitance. The results show that the main effect of the radiation is the generation of laterally inhomogeneous defects near the semiconductor surface.
Effect of Defect Bands on the Electrical Characteristics of Irradiated GaAs and Si
Proton bombarded p-Si and neutron irradiated n-GaAs have been studied by DLTS, current–voltage, and capacitance–voltage measurements in metal–semiconductor junctions. The junctions were prepared by evaporation of Al onto silicon and of gold onto GaAs. Both junctions exhibited defect bands after bombardment. The bombardment has shifted the Fermi-level pinning position, increased the ideality factor in both junctions, and also affected the temperature dependence of the ideality factor and that of the capacitance. The results show that the main effect of the radiation is the generation of laterally inhomogeneous defects near the semiconductor surface.
EFFECT OF SAMPLE PREPARATION ON WATER TREE RESISTANCE OF XLPE/SEBS BLENDS
The effects of an aromatic polymer, such as poly[styrene-b-(ethylene-co-butylene)b-styrene] (SEBS), and its preparation processes on water tree resistance, morphology, crystallinity, dielectric constant and dielectric loss tangent of crosslinked polyethylene (XLPE)/SEBS and XLPE/SEBS/ethylene vinyl acetate (EVA) blends were investigated. The XLPE/SEBS samples were characterized by means of differential scanning calorimetry, scanning electron microscopy, dielectric spectral analysis and the accelerated water treeing experiment. The results clearly showed that although SEBS was partially compatible with LDPE and it was dispersed evenly in XLPE matrix, the blends demonstrated excellent dielectric performances, such as dielectric constant and dissipation factor. The crystallinity of XLPE/SEBS blends was decreased with increase in SEBS content and it was further decreased with the addition of EVA. SEBS could effectively improve the water-tree resistance of XLPE and both SEBS and EVA were found to improve the water tree resistance of XLPE synergistically as expected. The differences in sample preparation processes could change the phase morphology and dielectric performance of the blends, and could also influence the dispersion of SEBS in XLPE matrix as well as the crystallinity of the blends. Different preparation processes led to different water tree resistance behaviours of the samples. The improvement of SEBS dispersion in XLPE matrix helped to improve the water tree resistance of XLPE.