Schottky barrier heights and conduction-band offsets of In1−xGaxAs1−yPy lattice matched to GaAs

Abstract

The Schottky barrier heights of ${\mathrm{Au/In}}_{\text{1−x}}{\mathrm{Ga}}_x{\mathrm{As}}_{\text{1−y}}{\mathrm{P}}_y$ contacts have been determined as a function of $y$ by the capacitance–voltage and temperature dependent current–voltage characteristics measurements. The barrier height is observed to increase as $y$ is increased for both $n$ - and $p$ -type materials, with a more rapid increase for the $p$ -type material. The compositional variation of the barrier heights for $\mathrm{Au}\mathrm{/n-}{\mathrm{In}}_{\text{1−x}}{\mathrm{Ga}}_x{\mathrm{As}}_{\text{1−y}}{\mathrm{P}}_y$ is found to be identical to that of the conduction-band offsets in ${\mathrm{In}}_{\text{1−x}}{\mathrm{Ga}}_x{\mathrm{As}}_{\text{1−y}}{\mathrm{P}}_y/\mathrm{GaAs}$ heterojunctions. A possible cause of this phenomenon is also discussed.