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Au/CaF2/nSi(111) structures with 4–5 monolayers of epitaxial fluoride are fabricated and electrically tested. The leakage current in these structures was substantially smaller than in similar samples reported previously. Simulations adopting a Franz-type dispersion relation with Franz mass of mF∼1.2m0 for carriers in the forbidden band of CaF2 reproduced the measured current-voltage curves quite satisfactorily. Roughly, these curves could also be reproduced using the parabolic dispersion law with the electron mass of me=1.0m0, which is a material constant rather than a fitting parameter. Experimental facts and their comparison to modeling results allow qualification of the crystalline quality of fabricated structures as sufficient for device applications.

Current-voltage characteristics of epitaxially grown Au∕CaF2∕Si(111) metal-insulator-semiconductor structures with thin (1.5–6nm) pseudomorphic fluoride layer have been studied. It was found that CaF2 films in these structures are of better insulating quality than those in the devices reported previously. Typical breakdown field for the fluorite layers was about 8×106V∕cm and the tunnel current did not exceed the values predicted by simulations with realistic parameters.

A method providing estimation of the trap density at metal∕ferroelectric interfaces of a depleted ferroelectric film located between back-to-back Schottky barriers has been developed. The method is based on the recharge of interface traps induced by external bias pulse applied to the metal∕ferroelectric∕metal structure. It is shown that the transient current under bias pulse can be controlled by the trap recharge on the reverse-biased interface. Using the method, the trap charge density on interfaces of the Pt∕PZT∕Ir(Ti∕SiO2∕Si) capacitor was found from transient-current measurements to be two orders of magnitude less than the remnant polarization of PbZrxTi1−xO3 film.

We present both theoretical and experimental results of our investigation into hot-electron luminescence in p-Si tunnel metal-oxide-semiconductor structures. The luminescence spectra of such structures contrast considerably with those of other silicon-based devices due to the fundamentally different method of charge injection, and we discuss several of their interesting features. The potential for direct modulation of low-intensity, low-efficiency infrared emission between 1.24 and 1.6μm is also demonstrated. Additionally, we investigate the role of self-heating, the influence of crystal axis orientation, and the possibility of anisotropy, and find the effect of each to be relatively small.

Bidirectional electric stresses are performed in metal—oxide—silicon capacitors with ultrathin (2.5 nm) oxides and with highly doped substrates. The observed effects are compared to those occurring under the conventional unidirectional constant-current overload. The effects observed after stress of ultrathin oxides bring into play defects of comparable nature to those noted for thick oxides, namely, neutral traps. Furthermore, soft breakdown events are scrutinized based on defect creation throughout the oxide and modulation of charge state trapping at the interfaces.