Electron transport properties of indium oxide – indium nitride metal‐oxide‐semiconductor heterostructures

Abstract

The structural, chemical and electron transport properties of In2O3/InN heterostructures and oxidized InN epilayers are reported. It is shown that the accumulation of electrons at the InN surface can be manipulated by the formation of a thin surface oxide layer. The epitaxial In2O3/InN heterojunctions show an increase in the electron concentration due to the increasing band banding at the heterointerface. The oxidation of InN results in improved transport properties and in a reduction of the sheet carrier concentration of the InN epilayer very likely caused by a passivation of surface donors. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Structure of cubic polytype indium nitride layers on top of modified sapphire substrates

“…The XRD spectrum indicates no evidence of appearance of either rhombohedral In 2 O 3 or hexagonal InN domains. These findings were additionally confirmed by electron dif- [16]. Note that, even with these rough oxide surfaces, a relaxed well-oriented 3C-InN structure was observed.…”

Electrical Conductivity of InN Nanowires and the Influence of the Native Indium Oxide Formed at Their Surface

“…6 Studies on oxidized InN layers also indicate that the electron accumulation layer is strongly influenced by oxides on the surface, which modify the surface Fermi level pinning position and hence the near surface carrier density. 20 In a recent study the universality of the InN electron accumulation layer at InN surfaces has been proposed. 7 In our experiments the conductivity of the InN nanowires surrounded by a native In 2 O 3 clearly exhibits a contribution from a high density electron accumulation layer, which is therefore assumed to form at the InN/In 2 O 3 interface.…”

“…For InN layers, a surface electron accumulation layer has been explained by In−In bonds on clean polar InN surfaces and is predicted to be absent under specific conditions on nonpolar surfaces . Studies on oxidized InN layers also indicate that the electron accumulation layer is strongly influenced by oxides on the surface, which modify the surface Fermi level pinning position and hence the near surface carrier density . In a recent study the universality of the InN electron accumulation layer at InN surfaces has been proposed …”

Electrical characterization of atomic layer deposited Al2O3/InN interfaces

“…The large surface accumulation layer has been attributed to the surface defects (In-O and In-In bonds) on the surface. 9,[13][14][15][16] Removal of the surface defects by chemical treatments could reduce the pinning in InN. Numerous papers have shown by spectroscopy analysis that acids and bases can effectively remove the native oxide on III-V and III-N semiconductor surface by reacting with the surface atoms.…”