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.
Fermi Level Position at Metal-Semiconductor Interfaces
The position of the Fermi level at a metal-semiconductor interface relative to the conduction band has been found to be a constant fraction of the semiconductor band gap for all but 3 of the 14 group IV or III-V semiconductors studied. In all cases, the position was essentially independent of the metal work function. This general result is not inconsistent with the limited theories of surface state energies now available. The three exceptional cases can be understood in terms of a first-order perturbation to the surface state energies correlated with a similar perturbation observed in the energy gap at the (111) zone edge. Experiments are also reported on Ga(As-P) alloys, and two II-VI materials showing distinctly different behavior.