Core-level photoemission and near-edge x-ray absorption fine-structure studies of GaN surface under low-energy ion bombardment

Petravić, M.; Deenapanray, Prakash; Coleman, Victoria A.; Kim, Ki-Jeong; Kim, Bongsoo; Li, Gang

doi:10.1063/1.1707232

Cited by 32 publications

(20 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…35 This assignment is in agreement with combined x-ray photoemission and NEXAFS characterization of Ar + bombarded GaN. 36 A similar RL has been observed in the N K edge NEXAFS spectra of N-rich Si x N y ͑Refs. 37-39͒ and Si x N y O z ͑Ref.…”

Section: B Nexafs Resultssupporting

confidence: 72%

Modification of the N bonding environment in GaN after high-dose Si implantation: An x-ray absorption study

Katsikini

Pinakidou

Paloura

et al. 2007

Journal of Applied Physics

View full text Add to dashboard Cite

The microstructure and electronic structure of epitaxially grown GaN, that has been subjected to high-dose Si implantation, is studied using x-ray absorption fine structure (XAFS) spectroscopy. More specifically, XAFS is used to probe the formation of N–Si bonds and to study the implantation induced distortions in the lattice. The analysis of the extended XAFS spectra reveals that implantation with 100keV Si ions with a fluence equal to 1×1018cm−2 renders the material amorphous and promotes the formation of Si–N bonds with a bond length equal to that corresponding in Si3N4. In addition to that, the N–Ga distances increase by ∼5% due to the lattice expansion caused by the incorporation of the Si ions and the formation of point and extended defects. The absence of long or midrange order is also verified by the near edge XAFS (NEXAFS) spectra where the characteristic peaks are smeared out. However, a characteristic sharp resonance line, that appears about 1eV above the absorption edge, indicates the existence of defect states which are strongly localized on the N atoms, most probably defect complexes involving N dangling bonds. In order to provide additional evidence on the nature of the implantation induced changes we resorted to simulations of the NEXAFS spectra using the FEFF8 code by applying chemical and lattice deformations in the immediate environment of the absorbing atom as well as to larger clusters.

show abstract

Section: B Nexafs Resultssupporting

confidence: 72%

Modification of the N bonding environment in GaN after high-dose Si implantation: An x-ray absorption study

Katsikini

Pinakidou

Paloura

et al. 2007

Journal of Applied Physics

View full text Add to dashboard Cite

show abstract

“…19 Excitations of core-electrons to an unoccupied defect level may produce an additional peak in NEX-AFS spectra, related directly to the presence of that specific defect in the material. 20,21 In the present study we focus on NEXAFS measurements around K-edges of boron and nitrogen in BN. For electronic transitions around the K-edge, where the initial state is a 1s state, the final states must contain contributions from p orbitals, for example in the form of s + p z ͑referred to as ‫ء‬ transitions͒ or p x + p y ͑ ‫ء‬ transitions͒ due to the dipole selection rule ⌬l= Ϯ 1, where ⌬l is the change of the angular momentum quantum number between the initial and final states.…”

Section: Resultsmentioning

confidence: 99%

Formation of defects in boron nitride by low energy ion bombardment

Peter

Božanić

Petravić

et al. 2009

Journal of Applied Physics

View full text Add to dashboard Cite

Formation of defects in hexagonal and cubic boron nitride ͑h-BN and c-BN, respectively͒ under low-energy argon or nitrogen ion-bombardment has been studied by near-edge x-ray absorption fine structure ͑NEXAFS͒ around boron and nitrogen K-edges. Breaking of B-N bonds for both argon and nitrogen bombardment and formation of nitrogen vacancies, V N , has been identified from the B K-edge of both h-BN and c-BN, followed by the formation of molecular nitrogen, N 2 , at interstitial positions. The presence of N 2 produces an additional peak in photoemission spectra around N 1s core level and a sharp resonance in the low-resolution NEXAFS spectra around N K-edge, showing the characteristic vibrational fine structure in high-resolution measurements. In addition, several new peaks within the energy gap of BN, identified by NEXAFS around B and N K-edges, have been assigned to boron or nitrogen interstitials, in good agreement with theoretical predictions. Ion bombardment destroys the cubic phase of c-BN and produces a phase similar to a damaged hexagonal phase.

show abstract

“…5, for the untreated GaN surface, the Ga 3d spectrum can be decomposed into three components in addition to the Ga-N component (19.6 eV): those chemically shifted by 0.92 eV toward higher binding energy (BE), 0.49 toward lower BE, and 1.76 eV toward lower BE, which can be assigned to Ga bonding to oxygen (Ga-O; 20.5 eV) [21,22], Ga bonding to N-H (Ga-NH; 19.21 eV) [23], and metallic Ga (17.5-18.4 eV) [24]. It has been reported that a metallic Ga layer forms on a damaged GaN surface [25]. Such a metallic Ga layer is readily oxidized even in air to afford Ga oxide on an untreated GaN surface.…”

Section: Chemical Propertiesmentioning

confidence: 96%

Structural and chemical characteristics of atomically smooth GaN surfaces prepared by abrasive-free polishing with Pt catalyst

Murata

Sadakuni

Okamoto

et al. 2012

Journal of Crystal Growth

View full text Add to dashboard Cite

Core-level photoemission and near-edge x-ray absorption fine-structure studies of GaN surface under low-energy ion bombardment

Cited by 32 publications

References 34 publications

Modification of the N bonding environment in GaN after high-dose Si implantation: An x-ray absorption study

Modification of the N bonding environment in GaN after high-dose Si implantation: An x-ray absorption study

Formation of defects in boron nitride by low energy ion bombardment

Structural and chemical characteristics of atomically smooth GaN surfaces prepared by abrasive-free polishing with Pt catalyst

Contact Info

Product

Resources

About