Effect of V2O5 nanoislands on the surface composition and structure of InP during thermal oxidation

The XPS investigations of the surface composition of nanoscale films formed by thermal oxidation of VxOy/InP heterostructures

“…In samples no. 2-5, the doublet peaks V2p 1/2 (522-523.9 eV) and V2p 3/2 (515.4-517.2 eV), characteristic for the V-O bond in vanadium oxides of different oxidation states: V 2 O 3 , VO 2 , V 2 O 5 [16,17], which correlates, to a certain extent with the XRD data obtained for these samples in earlier studies were detected [5].…”

“…The presence of vanadium compounds in oxidation states of +4 and +5 at the initial stage of oxidation (the first 10 min) confirms the catalytic mechanism of the process due to the easy transition V +5 ↔V +4 [19]. During the advanced stage of oxidation, the effect of V 2 O 5 islands was practically absent; the process is actually the proper oxidation of indium phosphide [5], which was due to the peculiarities of the V 2 O 5 presence in a small amount on the surface (islands).…”

“…Thus islands of nanoheterostructures (V 2 O 5 )/InP were formed. According to scanning electron (SEM) and scanning tunneling (STM) microscopy [5,7] the lateral dimensions of islands ranged from 80-150 nm, their surface concentration -15-20 mkm −2 . The choice of such a regime is justified by numerous experiments [5,7] and is due to optimization to maximize the rate of thermal oxidation for the nanoisland heterostructures compared with that of pure InP, which has been adopted as the standard.…”

“…The introduction of a chemostimulator in the oxidation system is possible in two ways: 1) through the gas phase in the thermal oxidation process; 2) directly on the semiconductor surface in the form of films or nanoscale islands before oxidation [4,5]. In the latter case, two groups of methods were used: hard (magnetron sputtering, electric explosion), acting on the surface prior to the thermal oxidation; soft (sol-gel processes, low-temperature metalo-organic chemical vapor deposition (MOCVD), etc.…”

Influence of the physicochemical nature of chemical stimulators and the way they are introduced into a system on the mechanism of the thermal oxidation of GaAs and InP

“…The electroexplo sion of wire, an HM that allows one to produce indi vidual chemical stimulator islands on a surface, mod eling active centers in the initial stage of the process, led to two step thermal oxidation. The first step had a markedly reduced effective activation energy (by almost one order of magnitude): 60-70 kJ/mol [20] against 270 kJ/mol for the intrinsic oxidation of InP.…”