Locating hexagonal and cubic phases in boron nitride using wavelength-selective optically detected x-ray absorption spectroscopy

Abstract

Locating hexagonal and cubic phases in boron nitride using wavelength-selective optically detected x-ray absorption spectroscopy, D.A. Evans, A.R. Vearey-Roberts, N.R.J. Poolton Appl Phys Lett 89, (2006) 161107Cubic and hexagonal phases of boron nitride (c-BN and h-BN) have been identified and located using optically detected x-ray absorption spectroscopy (ODXAS). Each phase was identified by distinct resonance features in the B K-edge absorption spectra. In a mixed-phase sample of predominantly c-BN, combined ODXAS and electron yield measurements suggested near-surface localization of h-BN. Using x-ray excited luminescence, emission bands due to each phase were identified and applied in wavelength-selective ODXAS to locate surface and bulk h-BN phases. These combined techniques provide a method of correlating the local structure and optical emission in these wide-gap semiconductors.Peer reviewe

The origin of luminescence from di[4-(4-diphenylaminophenyl)phenyl]sulfone (DAPSF), a blue light emitter: an X-ray excited optical luminescence (XEOL) and X-ray absorption near edge structure (XANES) study

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Electronic and Optical Properties of Magnesium Phthalocyanine (MgPc) Solid Films Studied by Soft X-Ray Excited Optical Luminescence and X-Ray Absorption Spectroscopies

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Determination of the optical band-gap energy of cubic and hexagonal boron nitride using luminescence excitation spectroscopy

“…This feature is entirely absent in pure σ -bonded c-BN, and confirms the structural integrity of each material in this study. (Its wider application to BN using wavelength-selectivity is described elsewhere [15].) The crucial point about the technique, however, is that the sample's structural identity is confirmed via the same luminescence yield in which the definitive bandgap measurements are to be extracted, as discussed in the following section.…”

“…(iii) The radiation can be extended into the XUV energy range where the technique of x-ray absorption spectroscopy provides a probe of the local bonding environment (the K -edges of both B and N lie within the energy range 190-450 eV). This is particularly sensitive to sp 2 and sp 3 bonding in BN and the spectra can be recorded using bulk-sensitive luminescence yield [15,16] as well as more conventional surface-sensitive electron yield methods. The advantage of using luminescence excitation, therefore, is that a self-consistent measurement method is available for determining both the sample's chemistry and structure and its band-gap energy.…”