Electric field dependence of the electron mobility in bulk wurtzite ZnO

Abstract

The electric field dependence of the electron mobility in bulk wurtzite zinc oxide (ZnO) material is studied. The low-field electron mobility is calculated as a function of doping concentration and lattice temperature. The results show that above nearly 50 K the electrical conduction is governed by activation through the bulk material and the conduction is then influenced by both lattice and impurity scattering mechanisms. The high-field characteristics are also considered. The transition between the low-field and high-field regions is specified. The negative differential mobility for bulk ZnO at room temperature is observed at electric fields above 280 kV/cm.

The s-d exchange model as the underlying mechanism of magnetoresistance in ZnO doped with alkali metals

“…This weak T -dependent mobility at high doping levels in ZnO has been already predicted by Alfaramawi [40]. In his model, scattering with ionized impurities and phonons are included as well as the electron-electron interaction [40,41,42]. Using the parameters adopted by Alfaramawi [40] in ZnO with an ionized impurity concentration of 1 × 10 20 cm −3 , a good agreement between this model and our experimental values is obtained, see Fig.…”

“…Both of them have a weak temperature dependence in the same way as the resulting electron mobility µ T µ 0 , see figure 4(c). This weak Tdependent mobility at high doping levels in ZnO has been already predicted by Alfaramawi [40]. In his model, scattering with ionized impurities and pho nons are included as well as the electron-electron interaction [40][41][42].…”

“…4c. This weak T -dependent mobility at high doping levels in ZnO has been already predicted by Alfaramawi [40]. In his model, scattering with ionized impurities and phonons are included as well as the electron-electron interaction [40,41,42].…”

“…(c) Resulting Hall electron mobility, µ 0 , (blue squares) as a function of the temperature. A corresponding fitting using Alfaramawi's expression [40] (red curve) is also shown.…”

Homologous Compounds ZnnIn2O3+n (n = 4, 5, and 7) Containing Laminated Functional Groups as Efficient Photocatalysts for Hydrogen Production

“…On the other hand, DOS and PDOS (Figure and Figure S2) reveal that In 5s orbitals have a major contribution to the conduction band (CB) and are in conformity with previous calculations that CBM tends to locate on the In–O networks. This explains the high conductivity of homologous compounds and the general trend for a better conductivity at lower n , as In 5s orbitals have a much wider dispersion than Zn 4s orbitals and In 2 O 3 has a much higher electron mobility than ZnO. ,,− Thereby, fast electron transport is more likely to occur in InO 6 octahedral layers rather than Zn­(In)­O 4(5) layers. In addition, contributions from In 4d orbitals to the valence band (VB) is clearly seen in the DOS and PDOS (Figure and Figure S2 for enlarged plot), in agreement with previous analysis that p–d hybridization between In and O is symmetry allowed in tetrahedral or trigonal-bipyramidal coordination (i.e., in Zn­(In)­O 4(5) layers).…”