Highly efficient electron gun with a single-atom electron source

Abstract

The authors have demonstrated highly collimated electron-beam emission from a practical electron gun with a single-atom electron source; ∼80% of the total emission current entered the electron optics. This ratio was two or three orders of magnitude higher than those of the conventional electron sources such as a cold field emission gun and a Zr∕O∕W Schottky gun. At the pressure of less than 1×10−9Pa, the authors observed stable emission of 20nA, which generates the specimen current of 5pA required for scanning electron microscopes.

Oxidation of CO Catalyzed by a Cu Cluster: Influence of an Electric Field

“…[48] This agrees with the experimental result that a single-atomended nanopyramid is a thermodynamically stable structure during the heating process. [64][65] For comparison purposes, the four-layer Cu(111) and twelve-layer Cu(211) surface systems are constructed with a vacuum width of 12 in the vertical direction, as seen in plots (b) and (c) of Figure 1. A· (22) and (2 1) unit cell is set for the flat Cu(111) and stepped Cu(211) surface, respectively, with a 5 5 1 k-point sampling.…”

Gas field ion source from an Ir∕W⟨111⟩ single-atom tip

“…These problems along with the random orientation of the nanoprotrusions still hinder their application in commercial FIB systems. 12 In this letter, we report our measurements on the gas source ion emission characteristics of Ir/ W SATs. 10 Later, Kuo et al further simplified the preparation process by replacing the tip cleaning and the vacuum deposition with electrochemical processes and successfully prepared several different types of noble metalcovered W͑111͒ SATs.…”

Confinement of the field electron emission to atomic sites on ultra sharp tips

“…For rough tip surfaces, isolated bright areas appear randomly based on the location and the local radius of the mini protrusions [4]. On the other hand, nanotips with a single atom apex have been proven to produce a highly collimated and coherent electron beam, which results in a well defined FEM spot [4][5][6][7][8]13].…”