64 research outputs found
Electrically detected magnetic resonance of carbon dangling bonds at the Si-face 4H-SiC/SiO interface
SiC based metal-oxide-semiconductor field-effect transistors (MOSFETs) have
gained a significant importance in power electronics applications. However,
electrically active defects at the SiC/SiO interface degrade the ideal
behavior of the devices. The relevant microscopic defects can be identified by
electron paramagnetic resonance (EPR) or electrically detected magnetic
resonance (EDMR). This helps to decide which changes to the fabrication process
will likely lead to further increases of device performance and reliability.
EDMR measurements have shown very similar dominant hyperfine (HF) spectra in
differently processed MOSFETs although some discrepancies were observed in the
measured -factors. Here, the HF spectra measured of different SiC MOSFETs
are compared and it is argued that the same dominant defect is present in all
devices. A comparison of the data with simulated spectra of the C dangling bond
(P) center and the silicon vacancy (V) demonstrates
that the P center is a more suitable candidate to explain the
observed HF spectra.Comment: Accepted for publication in the Journal of Applied Physic
Effect of Asphyxia on Thrombotest Values in Low Birthweight Infants
Thrombotest was used as a measure of coagulation status in 55 low birthweight infants. The initial levels were similar in both babies who were asphyxiated at birth and in those who had uncomplicated deliveries. On the other hand, 24 hours after giving vitamin K(1), a rise in the mean percentage thrombotest activity was confined to the normal delivery group. No significant rise occurred in the babies who suffered from hypoxia. It is suggested that fresh frozen plasma should be given particularly to asphyxiated low birthweight infants in an effort to diminish their liability to haemorrhage
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