Chapter 3 - Electrical properties of chemically tailored nanoparticles and their application in microelectronics

Abstract

This chapter introduces the physical principles of SET and basic SE structures where charging effects occur in the intended way. In further development of the ideas of SE, ligand-stabilized nanoparticles of noble metals have been recognized to be suitable building blocks for single-electron devices. These nanoparticles consist of a metal core with a defined size that is surrounded by a dielectric ligand shell that acts as an insulating barrier. Chemically tailored nanoparticles in the sub-10-nm range are suitable building blocks for SE devices. Their minute size combined with the well-defined insulation barrier, which is determined by the size and nature of the stabilizing ligand shell, opens access to ultrasmall electrical capacitances in the range of 10-19 F, a value that cannot be reached by classical techniques such as lithography because of their physical limits. Fabrication of a current standard using with the elementary charge e only one universal constant. This is of major imprtance for modern quantum metrology and could close the so-called "quantum metrology triangle," enabling one to find possible quantumelectrodynamical corrections to the corresponding fundamental relations among frequency, current, and voltage. The most remarkable opportunities for SE will occur in the field of digital circuits. An extension of the present-day technologies to smaller structures or the development of techniques that treat chemical nanostructures with conventional technologies will not reach the molecular size scale and, therefore, will waste many of the advantages of these structures.