N-channel MOSFETs fabricated on homoepitaxy-grown 3C-SiC films

We present results of the enhancement mode, n-channel 3C-silicon carbide (SiC) MOSFETs fabricated on homoepitaxy 3C-SiC films. The fabricated devices exhibit excellent gate-controlled linear and saturation regimes of operation. The average effective channel mobility is found to be 229 cm/sup 2//Vs. The breakdown field of the gate oxide is observed at be 11 MV/cm and the subthreshold swing is determined to be 280 mV/decade.     

Relations between the averaged 13C nuclear magnetic resonance chemical shift and the carcinogenic activity of polycyclic aromatic hydrocarbons.

13C Nuclear magnetic resonance (13C-NMR) spectra were measured for polycyclic aromatic hydrocarbons (PAH) to examine the correlation between their chemical shift and carcinogenicity. We confirmed our previous proposition that the carcinogenicity of PAH molecules can be predicted from the value of the averaged 13C-NMR chemical shift. It was also found, using the averaged chemical shift as a parameter, that several quantum chemical indices for the intermediate states of the metabolic transformation are correlated with the carcinogenic activity of PAH. This indicates that the averaged chemical shift can be applied to investigate the metabolic transformation of carcinogenicity.     

Balanced polarisation diversity receiver with built-in local laser diode

A new heterodyne receiver is demonstrated. The local laser diode (LD) was built-in and no fibre was used between the parts. The number of optical parts and assembly processes was reduced, and a better performance was achieved because there was no polarisation fluctuation of the local light. The effect of a mismatch in the beam profile is discussed.<>     

The study for the incipient solvation process of NaCl in water: the observation of the NaCl-(H2O)n (n = 1, 2, and 3) complexes using Fourier-transform microwave spectroscopy

Pure rotational spectra of the sodium chloride-water complexes, NaCl-(H(2)O)(n) (n = 1, 2, and 3), in the vibronic ground state have been observed by a Fourier- transform microwave spectrometer coupled with a laser ablation source. The (37)Cl-isotopic species and a few deuterated species have also been observed. From the analyses of the spectra, the rotational constants, the centrifugal distortion constants, and the nuclear quadrupole coupling constants of the Na and Cl nuclei were determined precisely for all the species. The molecular structures of NaCl-(H(2)O)(n) were determined using the rotational constants and the molecular symmetry. The charge distributions around Na and Cl nuclei in NaCl are dramatically changed by the complex formation with H(2)O. Prominent dependences of the bond lengths r(Na-Cl) on the number of H(2)O were also observed. By a comparison with results of theoretical studies, it is shown that the structure of NaCl-(H(2)O)(3) is approaching to that of the contact ion-pair, which is considered to be an intermediate species in the incipient solvation process.     

Electrokinetics of soft particles

Theories of electrokinetics of soft particles, which are particles covered with an ion-penetrable surface layer of polyelectrolytes, are reviewed. Approximate analytic expressions are given, which describe various electrokinetics of soft particles both in dilute and concentrated suspensions, that is, electrophoretic mobility, electrical conductivity, sedimentation velocity and potential, dynamic electrophoretic mobility, colloid vibration potential, and electrophoretic mobility under salt-free condition.     

Characterization of vacancy-type defects and phosphorus donors introduced in 6H-SiC by ion implantation

Received: 18 February 1998/Accepted: 5 June 1998     

Electrostatic interaction between an ion-penetrable sphere and an ion-impenetrable sphere

The exact expression for the electrostatic interaction between an ionpenetrable sphere and an ion-impenetrable rigid sphere is derived on the basis of the linearized Poisson-Boltzmann equation without recourse to Derjaguin's approximation.