Effect of Modification of an InP Surface by (V2O5 + PbO) AND (NiO + PbO) Oxide Mixtures of Different Compositions on the Thermal Oxidation Process and the Characteristics of the Formed Oxide Films

Vanadium oxide is an active chemostimulator of the oxidation of InP. This fact is manifested by an abrupt drop in the effective activation energy (EAE) of the process, a significant increase in the rate of growth of the thickness of the films (by 70 to 110%), and an improvement in their dielectric properties, due to effective bonding of the indium to its oxide form. All of this is evidence of a synchronous catalytic mechanism of oxidation of InP with deposited V2O5 layers of nanosize thickness. The use of a V2O5 + PbO mixture makes it possible to track the dynamics of decrease of catalytic action of V2O5 during oxidation under gradual increase in the PbO content of the mixture, with PbO entering as the oxygen transit agents for the InP components. The NiO + РbО mixture is composed of two oxides, both of which are oxygen transit agents. In view of this, the aim of the present work is to elucidate the combined chemostimulative action of nanosize layers of the oxide mixtures V2O5 + PbO and NiO + PbO, magnetron sputtered onto an InP surface, on the thermal oxidation of the obtained heterostructures. The practical absence of consumption of vanadium oxide (x-ray phase analysis data) confirms the presence during thermal oxidation of the (V2O5 + PbO)/InP heterostructures of a regeneration cycle of the V2O5 catalyzer. The lead oxide is fixed only at the early stages of the process, which is evidence of consumption of the PbO transit agent during InP oxidation. For (NiO + РbО)/InP (86 or 52 mole% РbО) heterostructures, consumption of NiO and PbO during the thermal oxidation process (XRD data) has been established, which confirms that the process proceeds via a transit mechanism. For oxide/phosphate films formed by oxidation of (V2O5 + PbO)/InP heterostructures, the size of the individual crystallites lies within the limits 100–150 nm (AFM data), whereas for (NiO + РbО)/InP heterostructures crystallites in the size range 150–200 nm are present in the oxide films.