Optimum built-in barrier height utilizing an extended concept of impedance matching
Schottky-barrier height optimization for high-frequency usage is analytically discussed with an extended concept of impedance matching. The optimum value of 0.3 eV is almost a universal constant under various operating conditions, and agrees well with the previous prediction obtained by large signal simulation and InxGa1-xAs experiments.
Schottky barrier height of n‐InxGa1−xAs diodes
The barrier heights φB of Au/n‐InxGa1−xAs diodes are measured by the capacitance‐voltage and saturation current methods. The composition dependence of the barrier height is φB (eV) = 0.95 − 1.90x + 0.90x2. A low barrier height with a relatively wide band gap is obtained in this system.
UV-B radiometry and dosimetry for solar measurements.
Biologically effective irradiance or dose of solar UV radiation was determined using a spectroradiometer, two broadband radiometers and two types of passive UV-dosimeters. The absolute erythema irradiance and the actinic irradiance were calculated from the solar spectrum measured with the spectroradiometer. It was demonstrated that the erythema irradiance is proportional to the actinic irradiance of solar radiation. The erythema irradiance was also determined using the two broadband radiometers which utilize a filter transmitting erythema spectra. Personal UV-dosimeters such as polysulphone and CR-39 were used to determine the erythema dose for a selected period of time. These results were used to estimate the accuracy of the broadband radiometers and UV-dosimeters. It was found that the results obtained from the broadband radiometers deviate from the absolute erythema irradiance by less than 20% during clear days between the hours of 11:00 and 13:00 Eastern Standard Time (EST) in Australia. The assessment of the erythema dose using passive dosimeters such as polysulphone and CR-39 could introduce an error as high as 40% if the calibration was not performed before undertaking experimental measurements.