Valence Offsets Research Articles

Discontinuities and bands alignments of strain-balanced III-V-N/III-V-Bi heterojunctions for mid-infrared photodetectors

We have developed a 10- and 14-band anticrossing (BAC) models to investigate the band structures of dilute nitrides and dilute bismides alloys. In fact, the addition of Bi or N to III-V semiconductors causes a significant reduction in the band gap energy and an enhancement of the spin-orbit splitting energy. Further, the conduction and valence offsets between III-V-N/III-V-Bi were also investigated for different nitrogen and bismuth concentrations. For III-V-N/III-V-Bi heterojunctions, the strain-balanced criteria were undertaken by the zero stress analysis. The band alignment of strain-balanced GaAsN/GaAsBi, InPN/InPBi and InAsN/InAsBi is a type II. For InSbN/InSbBi heterostructure, the band lineup can be type I or II.

Theoretical evaluation of zirconia and hafnia as gate oxides for si microelectronics.

Parameters determining the performance of the crystalline oxides zirconia (ZrO2) and hafnia (HfO2) as gate insulators in nanometric Si electronics are estimated via ab initio calculations of the energetics, dielectric properties, and band alignment of bulk and thin-film oxides on Si (001). With their large dielectric constants, stable and low-formation-energy interfaces, large valence offsets, and reasonable (though not optimal) conduction offsets (electron injection barriers), zirconia and hafnia appear to have considerable potential as gate oxides for Si electronics.

Valence Offsets of Three Series of Alloy Heterojunctions

Electron structure of three series of alloy heterojunctions (GaAs)x(Ge2)1-x/Ge,(AlAs)x(Ge2)1-x/Ge and AlxG1-xAs/Ge are calculated by linear muffin-tin orbital method with atomic-sphere approximation using the average-bond-energy theory in conjunction with a cluster expansion method. The results indicate the variations of ΔEν(x) at heterojunctions (GeAs)x(Ge2)1-x/Ge and (AlAs)x(Ge2)1-x/Ge are nonlinear, which are very different from that of AlxGa1-xAs/Ge.

Study on valence offsets at heterojunction

In this paper, the valence band offsets as a function of the alloy concentration x of the heterojunctions are studied, using the average-bond-energy theory in conjunction with a cluster expansion method. It is shown that the variation in is nearly linear and the calculation results are in very good agreement with relevant experimental data.