Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations

D. Gall, M. Städele, K. Järrendahl, I. Petrov, P. Desjardins, R. T. Haasch, Taeyoon Lee, J. E. Greene

Research output: Contribution to journalArticle

108 Citations (Scopus)

Abstract

Experimental and ab initio computational methods are employed to conclusively show that ScN is a semiconductor rather than a semimetal; i.e., there is a gap between the N 2p and the Sc 3d bands. Previous experimental investigators reported, in agreement with band structure calculations showing a band overlap of 0.2 eV, that ScN is a semimetal while others concluded that it is a semiconductor with a band gap larger than 2 eV. We have grown high quality, single crystalline ScN layers on MgO(001) and on TiN(001) buffer layers on MgO(001) by ultrahigh vacuum reactive magnetron sputter deposition. ScN optical properties were determined by transmission, reflection, and spectroscopic ellipsometry while in-situ x-ray and ultraviolet valence band photoelectron spectroscopy were used to determine the density of states (DOS) below the Fermi level. The measured DOS exhibits peaks at 3.8 and 5.2 eV stemming from the N 2p bands and at 15.3 eV due to the N 2s bands. The imaginary part of the measured dielectric function ε2 consists of two primary features due to direct Χ- and Γ-point transitions at photon energies of 2.7 and 3.8 eV, respectively. For comparison, the ScN band structure was calculated using an ab initio Kohn-Sham approach which treats the exchange interactions exactly within density-functional theory. Calculated DOS and the complex dielectric function are in good agreement with our ScN valence-band photoelectron spectra and measured optical properties, respectively. We conclude, combining experimental and computational results, that ScN is a semiconductor with an indirect Γ-Χ bandgap of 1.3±0.3 eV and a direct X-point gap of 2.4±0.3 eV.

Original languageEnglish
Article number125119
Pages (from-to)1251191-1251199
Number of pages9
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume63
Issue number12
Publication statusPublished - 2001 Jan 1

Fingerprint

Photoemission
Electronic structure
Metalloids
photoelectric emission
Semiconductor materials
electronic structure
Valence bands
Band structure
Energy gap
Optical properties
spectroscopy
Sputter deposition
Spectroscopic ellipsometry
Exchange interactions
Ultrahigh vacuum
Buffer layers
Photoelectron spectroscopy
Computational methods
Photoelectrons
Fermi level

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Gall, D., Städele, M., Järrendahl, K., Petrov, I., Desjardins, P., Haasch, R. T., ... Greene, J. E. (2001). Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations. Physical Review B - Condensed Matter and Materials Physics, 63(12), 1251191-1251199. [125119].
Gall, D. ; Städele, M. ; Järrendahl, K. ; Petrov, I. ; Desjardins, P. ; Haasch, R. T. ; Lee, Taeyoon ; Greene, J. E. / Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations. In: Physical Review B - Condensed Matter and Materials Physics. 2001 ; Vol. 63, No. 12. pp. 1251191-1251199.
@article{738211d139494324a63f58cf2be33fae,
title = "Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations",
abstract = "Experimental and ab initio computational methods are employed to conclusively show that ScN is a semiconductor rather than a semimetal; i.e., there is a gap between the N 2p and the Sc 3d bands. Previous experimental investigators reported, in agreement with band structure calculations showing a band overlap of 0.2 eV, that ScN is a semimetal while others concluded that it is a semiconductor with a band gap larger than 2 eV. We have grown high quality, single crystalline ScN layers on MgO(001) and on TiN(001) buffer layers on MgO(001) by ultrahigh vacuum reactive magnetron sputter deposition. ScN optical properties were determined by transmission, reflection, and spectroscopic ellipsometry while in-situ x-ray and ultraviolet valence band photoelectron spectroscopy were used to determine the density of states (DOS) below the Fermi level. The measured DOS exhibits peaks at 3.8 and 5.2 eV stemming from the N 2p bands and at 15.3 eV due to the N 2s bands. The imaginary part of the measured dielectric function ε2 consists of two primary features due to direct Χ- and Γ-point transitions at photon energies of 2.7 and 3.8 eV, respectively. For comparison, the ScN band structure was calculated using an ab initio Kohn-Sham approach which treats the exchange interactions exactly within density-functional theory. Calculated DOS and the complex dielectric function are in good agreement with our ScN valence-band photoelectron spectra and measured optical properties, respectively. We conclude, combining experimental and computational results, that ScN is a semiconductor with an indirect Γ-Χ bandgap of 1.3±0.3 eV and a direct X-point gap of 2.4±0.3 eV.",
author = "D. Gall and M. St{\"a}dele and K. J{\"a}rrendahl and I. Petrov and P. Desjardins and Haasch, {R. T.} and Taeyoon Lee and Greene, {J. E.}",
year = "2001",
month = "1",
day = "1",
language = "English",
volume = "63",
pages = "1251191--1251199",
journal = "Physical Review B-Condensed Matter",
issn = "1098-0121",
publisher = "American Physical Society",
number = "12",

}

Gall, D, Städele, M, Järrendahl, K, Petrov, I, Desjardins, P, Haasch, RT, Lee, T & Greene, JE 2001, 'Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations', Physical Review B - Condensed Matter and Materials Physics, vol. 63, no. 12, 125119, pp. 1251191-1251199.

Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations. / Gall, D.; Städele, M.; Järrendahl, K.; Petrov, I.; Desjardins, P.; Haasch, R. T.; Lee, Taeyoon; Greene, J. E.

In: Physical Review B - Condensed Matter and Materials Physics, Vol. 63, No. 12, 125119, 01.01.2001, p. 1251191-1251199.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations

AU - Gall, D.

AU - Städele, M.

AU - Järrendahl, K.

AU - Petrov, I.

AU - Desjardins, P.

AU - Haasch, R. T.

AU - Lee, Taeyoon

AU - Greene, J. E.

PY - 2001/1/1

Y1 - 2001/1/1

N2 - Experimental and ab initio computational methods are employed to conclusively show that ScN is a semiconductor rather than a semimetal; i.e., there is a gap between the N 2p and the Sc 3d bands. Previous experimental investigators reported, in agreement with band structure calculations showing a band overlap of 0.2 eV, that ScN is a semimetal while others concluded that it is a semiconductor with a band gap larger than 2 eV. We have grown high quality, single crystalline ScN layers on MgO(001) and on TiN(001) buffer layers on MgO(001) by ultrahigh vacuum reactive magnetron sputter deposition. ScN optical properties were determined by transmission, reflection, and spectroscopic ellipsometry while in-situ x-ray and ultraviolet valence band photoelectron spectroscopy were used to determine the density of states (DOS) below the Fermi level. The measured DOS exhibits peaks at 3.8 and 5.2 eV stemming from the N 2p bands and at 15.3 eV due to the N 2s bands. The imaginary part of the measured dielectric function ε2 consists of two primary features due to direct Χ- and Γ-point transitions at photon energies of 2.7 and 3.8 eV, respectively. For comparison, the ScN band structure was calculated using an ab initio Kohn-Sham approach which treats the exchange interactions exactly within density-functional theory. Calculated DOS and the complex dielectric function are in good agreement with our ScN valence-band photoelectron spectra and measured optical properties, respectively. We conclude, combining experimental and computational results, that ScN is a semiconductor with an indirect Γ-Χ bandgap of 1.3±0.3 eV and a direct X-point gap of 2.4±0.3 eV.

AB - Experimental and ab initio computational methods are employed to conclusively show that ScN is a semiconductor rather than a semimetal; i.e., there is a gap between the N 2p and the Sc 3d bands. Previous experimental investigators reported, in agreement with band structure calculations showing a band overlap of 0.2 eV, that ScN is a semimetal while others concluded that it is a semiconductor with a band gap larger than 2 eV. We have grown high quality, single crystalline ScN layers on MgO(001) and on TiN(001) buffer layers on MgO(001) by ultrahigh vacuum reactive magnetron sputter deposition. ScN optical properties were determined by transmission, reflection, and spectroscopic ellipsometry while in-situ x-ray and ultraviolet valence band photoelectron spectroscopy were used to determine the density of states (DOS) below the Fermi level. The measured DOS exhibits peaks at 3.8 and 5.2 eV stemming from the N 2p bands and at 15.3 eV due to the N 2s bands. The imaginary part of the measured dielectric function ε2 consists of two primary features due to direct Χ- and Γ-point transitions at photon energies of 2.7 and 3.8 eV, respectively. For comparison, the ScN band structure was calculated using an ab initio Kohn-Sham approach which treats the exchange interactions exactly within density-functional theory. Calculated DOS and the complex dielectric function are in good agreement with our ScN valence-band photoelectron spectra and measured optical properties, respectively. We conclude, combining experimental and computational results, that ScN is a semiconductor with an indirect Γ-Χ bandgap of 1.3±0.3 eV and a direct X-point gap of 2.4±0.3 eV.

UR - http://www.scopus.com/inward/record.url?scp=0034894644&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0034894644&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0034894644

VL - 63

SP - 1251191

EP - 1251199

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 1098-0121

IS - 12

M1 - 125119

ER -

Gall D, Städele M, Järrendahl K, Petrov I, Desjardins P, Haasch RT et al. Electronic structure of ScN determined using optical spectroscopy, photoemission, and ab initio calculations. Physical Review B - Condensed Matter and Materials Physics. 2001 Jan 1;63(12):1251191-1251199. 125119.