The oil-pressboard insulation is a typical composite insulation system widely used in the design and manufactory of large power apparatus. The implement of oil-pressboard insulation may lead to surface electrification...The oil-pressboard insulation is a typical composite insulation system widely used in the design and manufactory of large power apparatus. The implement of oil-pressboard insulation may lead to surface electrification and discharge at the interface under certain condition. It is of significant importance to take an insight into the phenomenon occurring at the interface. Through experiment, the pressboard is found as a porous material. The interface changes abruptly from bulk pressboard to the bulk oil as a result of the porous structure. A new model is proposed which divides the interface into bulk oil region, transition region, and bulk pressboard region. The width of the transition region is decided according to the microtome figure. The effective permittivity of the transition region is calculated using a new model based on fractal theory. The model is validated and compared with previous calculation model. The effect of the existence of transition region on the electric field distribution is discussed.展开更多
The a-Si : H/SiN_x : H sample series are investigated by means ofRaman scattering technique(RST). The result shows that due to thestructural mismatch between a- Si: H and a-SiN_x : H, severe induceddistortions are pro...The a-Si : H/SiN_x : H sample series are investigated by means ofRaman scattering technique(RST). The result shows that due to thestructural mismatch between a- Si: H and a-SiN_x : H, severe induceddistortions are produced in the interface of the heterojunction, andthese induced distortions tend towards a certain energy state. Theordering of the interface structure depends on the periodic number ofmuhilayer thin films.展开更多
The effects of wet re-oxidation annealing （wet-ROA） on the shallow interface traps of n-type 4H-SiC metal oxide-semiconductor （MOS） capacitors were investigated by Gray-Brown method and angle-dependent X- ray phot...The effects of wet re-oxidation annealing （wet-ROA） on the shallow interface traps of n-type 4H-SiC metal oxide-semiconductor （MOS） capacitors were investigated by Gray-Brown method and angle-dependent X- ray photoelectron spectroscopy technique. The results present the energy distribution of the density of interface traps （Dit） from 0 to 0.2 eV below SiC conduction band edge （Ec） of the sample with wet-ROA for the first time, and indicate that wet-ROA could reduce the Dit in this energy range by more than 60%. The reduction in Dit is attributed to the reaction between the introduced oxygen and the SiOxCy species, which results in C release and SiOxCy transformation into higher oxidation states, thus reducing the SiOxCy content and the SiOxCy interface transition region thickness.展开更多
基金Project(2009CB724504)supported by the National Basic Research Program of China
文摘The oil-pressboard insulation is a typical composite insulation system widely used in the design and manufactory of large power apparatus. The implement of oil-pressboard insulation may lead to surface electrification and discharge at the interface under certain condition. It is of significant importance to take an insight into the phenomenon occurring at the interface. Through experiment, the pressboard is found as a porous material. The interface changes abruptly from bulk pressboard to the bulk oil as a result of the porous structure. A new model is proposed which divides the interface into bulk oil region, transition region, and bulk pressboard region. The width of the transition region is decided according to the microtome figure. The effective permittivity of the transition region is calculated using a new model based on fractal theory. The model is validated and compared with previous calculation model. The effect of the existence of transition region on the electric field distribution is discussed.
文摘The a-Si : H/SiN_x : H sample series are investigated by means ofRaman scattering technique(RST). The result shows that due to thestructural mismatch between a- Si: H and a-SiN_x : H, severe induceddistortions are produced in the interface of the heterojunction, andthese induced distortions tend towards a certain energy state. Theordering of the interface structure depends on the periodic number ofmuhilayer thin films.
基金Project supported by the Fundamental Research Funds for the Central Universities,Ministry of Education,China(No.DUT11ZD114)
文摘The effects of wet re-oxidation annealing （wet-ROA） on the shallow interface traps of n-type 4H-SiC metal oxide-semiconductor （MOS） capacitors were investigated by Gray-Brown method and angle-dependent X- ray photoelectron spectroscopy technique. The results present the energy distribution of the density of interface traps （Dit） from 0 to 0.2 eV below SiC conduction band edge （Ec） of the sample with wet-ROA for the first time, and indicate that wet-ROA could reduce the Dit in this energy range by more than 60%. The reduction in Dit is attributed to the reaction between the introduced oxygen and the SiOxCy species, which results in C release and SiOxCy transformation into higher oxidation states, thus reducing the SiOxCy content and the SiOxCy interface transition region thickness.
