Energy-band alignments at ZrO2∕Si, SiGe, and Ge interfaces

Abstract

The energy-band alignments for the ZrO 2 / Si, ZrO 2 /Si 0.75 Ge 0.25 , and ZrO 2 / Ge interfaces have been studied using x-ray photoemission. The valence-band offsets of ZrO 2 / Si, ZrO 2 /Si 0.75 Ge 0.25 , and ZrO 2 / Ge interfaces are determined to be 2.95, 3.13, and 3.36 eV, respectively, while the conduction-band offsets are found to be the same value of 1.76± 0.03 eV for three interfaces. The upward shift of valence-band top accounts for the difference in the energy-band alignment at three interfaces.

Band structure of functional oxides by screened exchange and the weighted density approximation

“…The sX gap is close to experiment now. The valence band is 5.8 eV wide in sX compared to an experimental value of 6.5 eV [58]. The band dispersions in sX and GGA are quite similar.…”

“…2(a) shows the bands of the cubic (c-) phase of ZrO 2 . The calculated band gap is 5.34 eV, compared to an experimental value of Table 1 Calculated minimum band gaps for the GGA, sX and WDA methods in eV, compared to those from B3LYP [29 -32] and GW [16 -25] [57,58] and a GGA band gap of 3.4 eV. The sX gap is close to experiment now.…”

Quasi-zero lattice mismatch and band alignment of BaTiO3 on epitaxial (110)Ge

“…Significant research has been conducted on the high-j gate dielectrics such as HfO 2 , ZrO 2 , and Al 2 O 3 grown on (100)Ge, [10][11][12][13][14][15][16][17][18] (110)Ge, 1,15,16 and (111)Ge. 15,16 Among the new high-j dielectric materials, BaTiO 3 (BTO) directly grown on semiconductors has attracted attention for nonvolatile single transistor memory, 19 to reduce the susbthreshold swing and increase the on-current of a transistor.…”

Photoluminescent, morphological and electrical properties of ZrO2 and ZrO2:polyvinyl alcohol composite thin films

“…To understand the carrier conduction behavior, the energy band diagram of the structure is presented. According to the reported results by Wang et al [18] and Zheng et al [24], we found that the valenceband (conduction-band) offset of ZrO 2 /n-Si interfaces is 2.95 (1.76) eV, the band gap of ZrO 2 (Si) is 5.82 (1.11) eV and the electron affinity of ZrO 2 is 1.64 eV. The energy-band alignment for Au/ZrO 2 /n-Si interfaces is shown in Fig.…”

“…1 shows the PL spectra of the ZrO 2 (ZrO 2 :PVA) thin film. We used a Ne-Cu laser (the 248.6 nm line) as an excitation source and the energy (4.99 eV) of Ne-Cu laser is lower than the band-gap energy (5.82 eV [18]) of the ZrO 2 film. The PL excitation spectra of the broadband emission of ZrO 2 films were recorded in the energy range of 2.0-4.5 eV.…”