TY - JOUR

T1 - Passivation Mechanism of the Native Oxide/InAs Interface by Fluorine

AU - Valisheva, N. A.

AU - Bakulin, A. V.

AU - Aksenov, M. S.

AU - Khandarkhaeva, S. E.

AU - Kulkova, S. E.

PY - 2017/9/28

Y1 - 2017/9/28

N2 - Comparative experimental and theoretical studies of the fluorine/oxygen ratio influence on the structural and electronic properties of the anodic layer (AL)/InAs interface by XPS, HRTEM, C-V (77K) measurements and ab initio calculation of fluorine and oxygen adsorption on the InAs(111)A-(1 x 1) unreconstructed surface were performed. The well-ordered transition layer (TL), composed of indium and arsenic oxyfluorides, and extension of the interplanar distance at the fluorinated anodic layer (FAL)/InAs interface were experimentally revealed. The theoretical modeling of AL/InAs and FAL/InAs interfaces showed that the fluorinated TR formation removes the InAs surface distortion, whereas the In(InAs)-F-As(FAL) and In(InAs)-O-As(FAL) bond formation is a reason for the interplanar distance increase between FAL and the InAs surface. The decrease of the interface state density in the InAs bandgap and the Fermi level unpinning at the FAL/InAs interface result from the positive charge increase on FAL arsenic atoms near the InAs surface during the As-F bonds formation, while the electron accumulation on oxygen atoms and InAs subsurface arsenic atoms is the reason for the states appearance in the InAs bandgap at the anodic (native) oxide/InAs interface. (Graph Presented).

AB - Comparative experimental and theoretical studies of the fluorine/oxygen ratio influence on the structural and electronic properties of the anodic layer (AL)/InAs interface by XPS, HRTEM, C-V (77K) measurements and ab initio calculation of fluorine and oxygen adsorption on the InAs(111)A-(1 x 1) unreconstructed surface were performed. The well-ordered transition layer (TL), composed of indium and arsenic oxyfluorides, and extension of the interplanar distance at the fluorinated anodic layer (FAL)/InAs interface were experimentally revealed. The theoretical modeling of AL/InAs and FAL/InAs interfaces showed that the fluorinated TR formation removes the InAs surface distortion, whereas the In(InAs)-F-As(FAL) and In(InAs)-O-As(FAL) bond formation is a reason for the interplanar distance increase between FAL and the InAs surface. The decrease of the interface state density in the InAs bandgap and the Fermi level unpinning at the FAL/InAs interface result from the positive charge increase on FAL arsenic atoms near the InAs surface during the As-F bonds formation, while the electron accumulation on oxygen atoms and InAs subsurface arsenic atoms is the reason for the states appearance in the InAs bandgap at the anodic (native) oxide/InAs interface. (Graph Presented).

UR - http://www.scopus.com/inward/record.url?scp=85030531410&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.7b03757

DO - 10.1021/acs.jpcc.7b03757

M3 - Article

AN - SCOPUS:85030531410

VL - 121

SP - 20744

EP - 20750

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 38

ER -