Thermal oxides of In0.5Ga0.5P and In0.5Al0.5P

Abstract

An investigation of the chemical composition of wet thermal oxides grown on In0.5Ga0.5P and In0.5Al0.5P is reported. The oxides were grown in the temperature range 500–650 °C. An estimate of the expected oxide composition was obtained by the construction of three-dimensional phase diagrams of the In–Ga–P–O and In–Al–P–O systems. These diagrams indicate that under thermodynamic equilibrium, the oxide layers should be composed primarily of mixtures of InPO4 and GaPO4 on In0.5Ga0.5P and InPO4 and AlPO4 on In0.5Al0.5P. X-ray photoemission spectroscopy (XPS) sputter profiles were used to determine the distribution of elements in the oxide layers and to identify the chemical compounds. The binding energy shifts observed in the XPS data suggests that the oxides are composed primarily of metal phosphates with low concentrations of the metal trioxides. At lower growth temperatures, the oxides composition is uniform with depth, but there is an increasing depletion of In near the substrate interface as the growth temperature increases.

Local structural models of complex oxygen- and hydroxyl-rich GaP/InP(001) surfaces

“…Similar products are reported for the In 0.5 Ga 0.5 P alloy. 7,58 Fig -M is also wider for GaP than for InP, which derives from the symmetry-breaking distortion already described.…”

Electronic Properties and Device Applications of III-V Compound Semiconductor Native Oxides

“…48 In contrast, most of the column V element (P) in InAlP films upon wet oxidation remains in the film as phosphates. 23 It brings the role (if any) of hydrogen during wet oxidation into question and serves as a motivation to explore the dry oxidation of InAlP films.…”

Passivation of type II InAs/GaSb superlattice photodetectors with atomic layer deposited Al<sub>2</sub>O<sub>3</sub>

“…Studies on the surface and interface chemistry of III-V surfaces passivated with atomic layer deposited Al 2 O 3 has shown that it is possible to reduce the native oxides during deposition. This is due to the fact that formation of Al 2 O 3 is energetically preferred due to lower Gibbs free energy of Al 2 O 3 (-377.9 kcal/mol) [10]. The Gibbs free energies of Ga 2 [11,12] which are all higher than Al 2 O 3 .…”

“…Similar reaction pathways with oxides of other metal atoms are also possible. These are so called interfacial self cleaning reactions of surface oxides [10].…”