Electrophysical Properties and Thermal Stability of Pt/InAlAs Schottky Barrier Diodes

In this study, the current-voltage characteristics of $\mathbf{P t} / \mathbf{I n A l A s}$ Schottky barrier diodes with a chemical preparation of InAlAs surface are investigated. The temporal dependencies of barrier height and ideality factor values for the annealing temperatures of 300,350 and $400^{\circ} \mathrm{C}$ are obtained. Abrupt step changes in barrier height dependences for chemically prepared Schottky diodes were observed after 1, 9 and 16 min at the temperatures of 400,350 and $300{}^{\circ} \mathrm{C}$, respectively. The activation energy of solid-state reaction at the Pt/InAlAs interface was calculated to be $0.73 \pm 0.14 \mathrm{eV}$ according to Arrhenius equation. The Pt diffusion depth was estimated using the capacitance-voltage characteristics of chemically prepared Schottky diodes at a negative bias voltage. C-V measurements were made for Schottky diodes annealed at $400{}^{\circ} \mathrm{C}$ for 1,9 and 16 min. Significant changes in the capacitance were observed only after 1 min of annealing, which is correlated with barrier height changes. According to calculations, the Pt diffusion depth is $21 \mathbf{n m}$.