Papers by Keyword: Interface Density

Abstract: In this work we demonstrate the application of stereology-based image analysis for the characterization of highly porous cellular ceramics (alumina foams) prepared by biological foaming with yeast and subsequent drying (80-105 °C) and firing (1570 °C). It is shown that the ceramics prepared usually have total porosities in the range 78-84 % and that the porosities made up by large pores (volume fraction of foam bubbles) are usually in the range 58-75 %. Further it is shown that the mean chord length and the Jeffries size, i.e. pore size measures related to the interface density and the mean curvature integral density, respectively, are relatively close to each other (usually 0.8-1.4 and 0.8-1.2 mm) with a ratio close to unity (0.9-1.3) and that the mean surface-to-surface distance of pores gives a realistic picture of the average pore wall thickness (usually 0.46-0.69 mm). Using a special processing variant (excess ethanol addition) it is possible to obtain microstructures with lower porosity (total porosity 68-70 %, foam bubble volume fractions 50-56 %) and smaller pore size (approx. 0.5 mm). Absolute errors are calculated using normalized deviations corresponding to 95 % reliability in the Student distribution and the standard errors for the quantities in question (both observed and estimated). Relative errors are found to be below 12 % when the number of measurements is of order 400-1000.

Abstract: Metal-oxide-semiconductor (MOS) structure is highly sensitive to SiO₂-Si interface. It will reflect parameters such as interface density and oxide layer charge expediently. For the sake of researching of radiation effect of MOS structure irradiated by electron, we adopted 0.8 MeV electron at dosage between 2×10¹³ cm^-2~1×10¹⁴ cm^-2 as radiation source respectively. We found that electron radiation will induce interface density at SiO₂-Si interface. According to comparison with C-V curve of MOS structure at high frequency and low frequency, we obtain that the experimental data of interface density is up to 10¹⁴(cm^-2eV^-1). In addition, we also obtain the relationship between the parameter and radiation dosage.

Abstract: ×MOS structure has been radiated by electron, dosage is 2×10¹³ cm^-2 ~ 1×10¹⁴ cm^-2. The interface density distributing in energy band has been tested by quasi-static method. It is found that interface density increase while electron dosage increasing. When dosage arrived to 1×10¹⁴ cm^-2, interface density arrives to 10¹³(cm^-2eV^-1),which is two order of magnitude higher than without irradiation. Further more, the shapes of density increase curve are completely different.