In the 1970’s, Albert Crewe demonstrated with scanning transmission electron microscopy that field emission sources allowed spectacular improvement (i.e., atomic resolution) in the field of electron microscopy [1]. Several groups in the USA, Great Britain, and France began to work on point ion sources in order to bring similar improvements to ion instruments, especially to secondary ion mass sp...

The electron field emission of tetrahedral amorphous carbon ~ta-C! films deposited by filtered cathodic vacuum arc is reported. The ta-C films were found to have a threshold field ranging from 18 to 28 V mm, depending on the sp content. The nitrogenated ta-C ~ta-C:N! films show a lower threshold field of 12 V mm as compared to the ta-C films. The threshold field appears to be dependent on the f...

Graphene nanosheets have been synthesized from commercial expandable graphite by heating in a microwave oven and dispersing in ethanol by ultrasonication. Scanning and transmission electron microscopy and electron energy-loss spectroscopy and atomic force microscope showed that the nanosheets were about 2 nm in thickness and 10 microm in diameter. The field emission of the graphene sheets has b...

In this paper we report a facile route for the synthesis of controlled CuO nanoarchitectures directly grown on a copper substrate by a one-step simple chemical route with varying concentration of non-ionic surfactant PEG-6K. The phase purity and degree of crystallinity of the as-developed nanostructures were systemically investigated by X-ray diffraction, X-ray photoelectron spectroscopy and hi...

The authors report the field emission FE properties of individual ZnO nanowire field emitters. ZnO nanowire field emitter directly grown on a Pt tip showed a much better field emission current delivery than the attached nanowire emitters due to better contact properties. The emission current and field emission microscopy pattern of the ZnO nanowire are strongly influenced by adsorbates. After t...

Impurity-free silicon oxide nanowires were synthesized on a 3 cm x 3 cm alumina plate uniformly by thermal evaporation of a mixture of powder of graphite powders and SiOx@Si core-shell particles under argon atmosphere with a flow rate of 50 sccm at 1100 C for 3 hours. The assynthesized products characterized by field-emission scanning electron microscopy, field-emission transmission electron mi...

Leaf stomatal characteristics of Siberian elm (Ulmus pumila) were investigated by electron microscopy and white light scanning interferometry. On the basis of average annual precipitations, two types of tree specimens were collected from Korea, China, and Mongolia: (1) trees under normal environmental conditions and (2) trees under arid conditions. Field emission scanning electron microscopy re...

In this work we present a method for tip-sample distance control in probe microscopy and probe recording by using field emission current detection as a feedback signal. Field emission currents flow when a large enough electric field is applied between the probe tip and the recording medium. The current varies exponentially with the applied electric field, which in turn is more or less proportio...