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Diodes on the nanometer scale generally show non-ideal transport characteristics. In this paper, the transition of a conventional Schottky diode to a nano-diode is investigated. It is shown that electrostatic effects in small lithographically fabricated diodes can lead to a considerably thinner Schotty barrier, with the consequence of a greatly enhanced tunnelling current. We present numerical simulations as well as analytical calculations of the potential barrier shape in small devices, demonstrating this scaling effect. Special focus is placed on the role of the interconnects.

Strong 1/ f γ resistance noise is observed in the insulating phase in a two-dimensional electron system in high-mobility silicon metal-oxide-semiconductor field-effect transistors (MOSFETs). The noise power increases with decreasing temperature. This suggests the formation of the electron glass at low carrier densities.

Coplanar superconductor-semiconductor-superconductor junctions are fabricated using CoSi2 as a superconductor and heavily doped Si as a semiconductor. The CoSi2 is formed in a self-aligned process. In this article the fabrication process of the junctions is presented. Two types of samples are fabricated. The current path of samples of the first type is not well defined. Additional fabrication steps are done to constrict the current path of the second type of samples to the small silicon link. Measurements on both types of samples are presented. Supercurrent and characteristic behaviour in the voltage carrying state (subharmonic gap structure) is measured and analysed on samples with a well defined current path.

The magnetic field Bc, in which the electrons become fully spin-polarized, is found to be proportional to the deviation of the electron density from the zero-field metal–insulator transition in a two-dimensional electron system in silicon. The tendency of Bc to vanish at a finite electron density suggests a ferromagnetic instability in this strongly correlated electron system.

Hall coefficient measurements are reported for the two-dimensional electron system in silicon MOSFETs for densities throughout the metallic phase and very near the transition to insulating behavior.

The critical pair-breaking current in narrow aluminium filaments is measured as a function of temperature to about T T c = 0.3 . Down to T T c = 0.5 agreement with theoretical predictions based on Eilenberger's equations is found.