Determination of band offsets, chemical bonding, and microstructure of the (_{Tbx Sc1-x) 2} O₃ /Si system

TY - JOUR

T1 - Determination of band offsets, chemical bonding, and microstructure of the (Tbx Sc1-x) 2 O3 /Si system

AU - Geppert, I.

AU - Eizenberg, M.

AU - Bojarczuk, N. A.

AU - Edge, L. F.

AU - Copel, M.

AU - Guha, S.

N1 - Funding Information: The financial support of the Russell Berrie Nanotechnology Institute at the Technion is acknowledged. The work at IBM was performed by the Research Alliance Teams at various IBM Research and Development Facilities.

PY - 2010/7/15

Y1 - 2010/7/15

N2 - The energy band gap, the band alignment with Si, and the chemical bonding of 4-5 nm thick (TbxSc1-x)2 O3 dielectric films were investigated as a function of composition. Films with x=0, 0.5, and 1 were prepared by a molecular beam deposition technique on silicon substrates. The structure of the dielectric films was characterized by high resolution transmission electron microscopy. We found that upon deposition, a silicate and a silicon oxide layer were formed at the dielectric/silicon interface for all compositions. X-ray photoelectron spectroscopy was used to determine the band gap, as well as the energy band alignment with Si and the chemical structure of the films. Energy gap values of 6.0±0.2 and 7.5±0.2 eV were obtained for pure Sc2O3 and Tb 2 O3, respectively, while for the mixed layer (x=0.5) a value of 6.8±0.2 eV was extracted. It was found that the valence band offset does not change with Sc addition to Tb2O3, while the conduction band offset increases with x, from a value of 2.9±0.2 eV for the x=0 (pure Sc2O3) to a value of 5.7±0.2 eV for x=1 (pure Tb2O3).

AB - The energy band gap, the band alignment with Si, and the chemical bonding of 4-5 nm thick (TbxSc1-x)2 O3 dielectric films were investigated as a function of composition. Films with x=0, 0.5, and 1 were prepared by a molecular beam deposition technique on silicon substrates. The structure of the dielectric films was characterized by high resolution transmission electron microscopy. We found that upon deposition, a silicate and a silicon oxide layer were formed at the dielectric/silicon interface for all compositions. X-ray photoelectron spectroscopy was used to determine the band gap, as well as the energy band alignment with Si and the chemical structure of the films. Energy gap values of 6.0±0.2 and 7.5±0.2 eV were obtained for pure Sc2O3 and Tb 2 O3, respectively, while for the mixed layer (x=0.5) a value of 6.8±0.2 eV was extracted. It was found that the valence band offset does not change with Sc addition to Tb2O3, while the conduction band offset increases with x, from a value of 2.9±0.2 eV for the x=0 (pure Sc2O3) to a value of 5.7±0.2 eV for x=1 (pure Tb2O3).

UR - http://www.scopus.com/inward/record.url?scp=77955789243&partnerID=8YFLogxK

U2 - 10.1063/1.3427554

DO - 10.1063/1.3427554

M3 - 文章

AN - SCOPUS:77955789243

SN - 0021-8979

VL - 108

JO - Journal of Applied Physics

JF - Journal of Applied Physics

IS - 2

M1 - 024105

ER -