Angle-resolved photoemission study of the valence-band structure ofVN0.89(100)

Chemical bonding and electronic structure in binary VNy and ternary T1−xVxNy nitrides

“…[13][14][15][16] Theoretical and experimental studies have demonstrated that the introduction of nitrogen vacancies leads to the appearance of new occupied states close to the metallic 3d contribution below the Fermi level. [6][7][8]10,11,13,14,16 A vacancyinduced structure in valence-band ͑VB͒ spectra was not observed in earlier experimental UPS studies of substoichiometric vanadium nitrides while a pronounced vacancyinduced peak appeared in the XPS results. 5,8 In fact, the vacancy-induced states show up in emission spectra only for excitation photon energies above 30 eV as demonstrated by Indlekofer et al and Lindström et al 8,10 Similar effects were reported for TiN y , which is the most investigated material.…”

“…[6][7][8]10,11,13,14,16 A vacancyinduced structure in valence-band ͑VB͒ spectra was not observed in earlier experimental UPS studies of substoichiometric vanadium nitrides while a pronounced vacancyinduced peak appeared in the XPS results. 5,8 In fact, the vacancy-induced states show up in emission spectra only for excitation photon energies above 30 eV as demonstrated by Indlekofer et al and Lindström et al 8,10 Similar effects were reported for TiN y , which is the most investigated material. 6,7,11,12 In the present article, we focus on the electronic structure of the Ti-V-N system, in particular substoichiometric sputtered VN y films.…”

“…17,18 The electronic structure of fcc MeN ͑MeϭTi, V͒ mononitrides crystallizing in an ideal NaCl type of structure ͑B1-type͒ has been studied by various techniques such as ultraviolet photoemission spectroscopy ͑UPS͒ and x-ray photoemission spectroscopy ͑XPS͒, 5-8 electron-energy-loss spectroscopy ͑EELS͒, 5,9 angle-resolved photoemission spectroscopy ͑ARPS͒ and Auger electron spectroscopy ͑AES͒. [10][11][12] Theoretical density of states ͑DOS͒ calculations using different methods are also reported in the literature. [13][14][15][16] Theoretical and experimental studies have demonstrated that the introduction of nitrogen vacancies leads to the appearance of new occupied states close to the metallic 3d contribution below the Fermi level.…”

“…All these properties have stimulated many detailed experimental and theoretical studies of their electronic structures. [3][4][5][6][7][8][9][10][11][12][13][14][15][16] The physical properties are primarily related to the electronic band structure. Stoichiometry deviation and structural disorder ͑vacancies, antisite, and interstitial atoms͒ influence the physical properties of these materials with open structures.…”

The growth of epitaxial VN(111) nanolayer surfaces

“…Significantly, the region between 2 and 3 eV binding energy shows no spectral feature under He II excitation. A vacancy induced spectral structure in this energy region has been predicted theoretically by Marksteiner et al [20] and has been detected subsequently by angle-resolved photoemission measurements by Lindströ m et al [21]; the vacancy derived feature required photon energies hm > 31 eV to show up with detectable spectral intensity. The absence of spectral structure between 2-3 eV in the He II spectrum (Fig.…”