The Effect of Certain Complex Chemostimulators and Modifi ers on InP Thermal Oxidation

Abstract

It is advisable to control characteristics and rate of formation of nanoscale fi lms on InP by introducing chemostimulators, modifi ers, or both simultaneously during the thermal oxidation of semiconductors. The chemostimulating effect of the compounds is determined by their transit role as oxygen transmitters or their catalytic function. Modifi ers can affect the composition, surface morphology, structure, and properties of the fi lm without changing the fi lm growth rate. The effect of chemostimulators and modifi ers on a single process of fi lm synthesis with the desired properties was assumed to be productive. Purpose: Establishment of the effect of certain complex chemostimulators and modifi ers on the kinetics, growth mechanism, and properties of complex oxide fi lms on InP in the nanoscale thickness range. The object of the study was indium phosphide FIE-1A orientation (100). SnO2/InP and (40 % Co3O4+60 % MnO2)/InP heterostructures with a layer thickness of ~ 30 nm were formed by magnetron sputtering. Sulphate was deposited through the aerosol phase, followed by air drying and annealing at 200 °C for 30 min for the formation of the Bi2(SO4)3/InP heterostructures. SnO2/InP and InP samples were thermally oxidized under the infl uence of AlPO4 and Bi2(SO4)3, respectively, introduced into the gas phase in the temperature range 490-570 °C in an oxygen stream for 60 min. The thickness of the fi lms was controlled by laser and spectral ellipsometry and their phase and elemental composition were established by XRD and Auger electron spectroscopy, respectively. For the determination of the electrophysical properties of the films, the contacts were sprayed with aluminium and the resistivity was determined. The fundamental role of the physicochemical nature of the chemostimulator, its ability to transit interactions and the renewability of oxide forms in the process of InP thermal oxidation was established. The introduction of phosphate groups from AlPO4 into thermal oxide fi lms, with or without the deposition of SnO2 on the surface, led to the fi lm resistance similar to that for the oxidation of SnO2/InP heterostructures without the additional introduction of phosphates and was 8.5·107 Ohm·cm. Bi2(SO4)3, being a modifi er of the composition and properties of the fi lms, did not have a signifi cant chemostimulating effect. Films grown under its infl uence had a semiconductor characteristics (r ~ 106 Ohm·cm). The most effective was a 40 % Co3O4+ 60 % MnO2 complex chemostimulator, which determined the accelerated (up to 70 %) formation of fi lm by the catalytic-transit mechanism (up to 70 %), being a part of the synthesized fi lms and capable of purposefully modifying their properties by varying the content of components in it (XRD, SE).

Keywords

• indium phosphide
• nanoscale fi lms
• chemostimulated oxidation
• chemostimulator
• modifi er
• modifi cation of composition and properties.