The electronic work function of polycrystalline solid solution alloys is being analytically calculated using three different approaches. All approaches are derived by assuming that the alloys are in equilibrium and therefore surface segregation causes a difference between the surface composition and the bulk composition. An approach based on the image force, an approach based on the dipole layer formed due to electronegativity differences, and a simple surface concentration approach are compared to published experimental results. The image force model has a good agreement with the experiments, while the dipole-layer approach has a poor agreement, challenging the conventional concept of the double layer.

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A method is proposed for characterization of the electrostatics of self-assembled monolayers (SAMs). The method is based on the extraction of the metal’s effective work function in metal-oxide-semiconductor capacitors, where the SAM is positioned at the metal-oxide interface. Hexyltrichlorosilane molecules assembled on SiO2 are used as a model system for this method. A band offset of 0.5 ± 0.15 eV is observed in the SAM sample when compared to a reference with no molecules. Spectroscopy is employed to confirm the presence of silane anchoring groups after metal deposition.

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Hf-Ni alloys are studied as a gate electrode for metal-oxide-semiconductor devices. The Hf-Ni solid-state amorphization couple encompasses several metallurgical phenomena which are investigated at the nanoscale and are correlated with the macroscopic electrical properties of devices. The dependence of the Fermi level position on the alloy composition is studied both on SiO2 and on HfO2. In order to isolate the effects of interfacial and dielectric charges and dipoles, the dependence of the vacuum work-function values on the composition is also studied. The Fermi level positions of the alloys do not depend linearly on the average composition of the alloys and are strongly affected by Hf enrichment at the HfNix/dielectric interface and the HfNix surface. We note a constant shift of 0.4 eV in the Fermi level position on HfO2 compared to SiO2. In addition, characterization of the composition, structure, and morphology reveals Kirkendall voids formation when the bottom layer consists of Ni, and an oxygen-scavenging effect when the bottom layer is Hf.