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A metal–interlayer–semiconductor (MIS) structure that is realized by inserting an ultrathin interlayer between a contact metal and a semiconductor has been investigated recently as a low-resistance non-alloyed contact structure. However, a comprehensive and systematical investigation of Schottky barrier height (SBH) modulation through the insertion of an interlayer depending on the contact surface orientation has not been conducted despite its importance for its use in multi-gate transistors. Therefore, in this work, the SBH modulation of the MIS contact structure for different contact surface orientations is systematically investigated, and a comprehensive analysis platform of the MIS contact structure is suggested. Two factors, (1) alleviation of Fermi-level pinning due to metal-induced gap states and interface states and (2) formation of the interface dipole, contribute to the SBH modulation in the MIS contact structure. Their contributions depending on the contact surface orientation are evaluated through a comparison of the contact structures on (100)- and (110)-oriented germanium (Ge). These factors and how they should be considered for a certain contact surface in Ge-channel multi-gate transistors are investigated. The investigation and the proposed analysis platform will contribute to the design of high-performance non-alloyed contact schemes for next-generation multi-gate transistors. [ABSTRACT FROM AUTHOR]

We investigated the dependence of absolute SnS band-edge energies on surface orientation using density functional theory and GW method for all surfaces with Miller indices -3 ≤ h; k; l ≤ 3 and found variations as large as 0.9 eV as a function of (hkl). Variations of this magnitude may affect significantly the performance of photovoltaic devices based on polycrystalline SnS thin-films and, in particular, may contribute to the relatively low measured open circuit voltage of SnS solar cells. X-ray diffraction measurements confirm that our thermally evaporated SnS films exhibit a wide distribution of different grain orientations, and the results of Kelvin force microscopy support the theoretically predicted variations of the absolute band-edge energies. [ABSTRACT FROM AUTHOR]

Orientation-engineered 0.755(Bi0.5Na0.5)TiO3-0.065BaTiO3-0.18SrTiO3 thin films deposited on Nb doped SrTiO3 (N:STO) single crystalline (001), (110), and (111) substrates via a sol-gel process were investigated. Highly epitaxial growth was observed in the as-deposited thin films. Excellent piezoelectric properties are exhibited by the (111) oriented thin films with the highest strain level (0.32%) and local effective piezoelectric coefficient (d33=210 pm/V). Strong orientation dependence of piezoelectric properties on the thin films is attributed to the relative alignment of crystallites and spontaneous polarization vector. These findings are of great significance for piezo-micro electro mechanical systems. [ABSTRACT FROM AUTHOR]

We engineered various orientations of NiO layers for NiO-based heterostructures (NiO/Au/STO) to investigate their effects on the generation of hot electrons and holes. Our calculation and experimental results suggested that bandgap engineering and the orientation of the hole transport layer (NiO) were crucial elements for the optimization of photoelectric responses. The (100)-orientated NiO/Au/STO achieved the highest photo-current density (∼30 μA/cm2) compared with (111) and (110)-orientated NiO films, which was attributed to the (100) films's lowest effective mass of photogenerated holes (∼1.82 m0) and the highest efficiency of separating and transferring electron-holes of the (100)-orientated sample. Our results opened a direction to design a high efficiency photoelectric solar cell. [ABSTRACT FROM AUTHOR]

Valence band structure and surface states of InN with (0001), (000-1), (1-100), and (11-20) orientation were investigated in situ after growth using photoelectron spectroscopy. Depending on surface orientation, different occupied surface states are identified and differentiated from bulk contributions. For N-polar, m-plane, and a-plane InN, the surface states are located at the valence band maximum, while In-polar InN features surface states close to the Fermi level. The surface band alignment correlates with the position of surface states. For InN(0001), a much larger surface downward band bending is observed compared to N-polar, m-plane, and a-plane InN, where almost flat band conditions occur. [ABSTRACT FROM AUTHOR]

AlSb is grown by molecular beam epitaxy. The evolution and the relaxation of the deposited AlSb layer is investigated by synchrotron-based in situ grazing incidence x-ray diffraction (GID), and the analysis of the real space distribution is performed by atomic force microscopy. AlSb forms islands with (111)A polarity and {110} surface orientations with different side facets following the Volmer-Weber growth mode. GID investigations reveal facet rods originating from AlSb{110} islands. It is shown that a concentration of only 0.7% AlSb{110} oriented domains influences the diffraction pattern in such a way that additional crystal truncation rods parallel to the surface appear. [ABSTRACT FROM AUTHOR]