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Ge (100) surfaces were irradiated by heavy Bi and Bi ions extracted from a Bi-liquid metal ion source in a mass separated focused ion beam system with energies of 30 and 60 keV, respectively. Networks of different nanoporous (or sponge like) structures were found depending on ion energy, fluence, angle of incidence, and irradiation temperature. The porous and amorphous surface structures are explained in terms of high concentration vacancies close to the surface. The surface modification was investigated using SEM and AFM imaging and FIB for cross section preparation. [ABSTRACT FROM AUTHOR]

Abstract: A GaBi alloy liquid metal ion source has been studied. From an analysis of the source mass spectra as a function of emission current, a mechanism is suggested for the production of single- and double-charged ions. There is good agreement with the results of Swanson''s investigations of a pure Bi source. [Copyright &y& Elsevier]

Abstract: A mass separated focused ion beam (FIB) is a very useful tool to fabricate nanostructures by writing implantation within an ion beam synthesis process. In these investigations the IMSA-OrsayPhysics FIB, equipped with a Co36Nd64 alloy liquid metal ion source, was applied. Si(100) and (111) wafers were implanted with 60 keV Co++ ions in the dose range of 2·1016 to 2·1017 cm−2. Implantation parameters were investigated, like pixel dwell time, relaxation time (time between two cycles), dose rate as well as the pixel overlapping factor. The subsequent annealing was done in a two step process, namely 600 °C for 60 min and 1000 °C for 30 min in a N2 ambient. The results obtained by SEM investigations in terms of continuous nanowire structures following the <110> direction and interrupted CoSi2 pattern in the <100> direction show a clear dependence on the time scale as well as the scanning mode of the irradiation. Structure sizes as small as 10 nm are demonstrated. The formation of CoSi2 nanostructures is explained by precipitation, Ostwald ripening and coarsening leading to a shrinking of the initial implanted profile. [Copyright &y& Elsevier]

We propose a method for deterministic implantation of single atoms into solids which relies on a linear ion trap as an ion source. Our approach allows a deterministic control of the number of implanted atoms and a spatial resolution of less than 1 nm. Furthermore, the method is expected to work for almost all chemical elements. The deterministic implantation of single phosphor or nitrogen atoms is interesting for the fabrication of scalable solid state quantum computers, in particular for silicon and diamond based schemes. A wide range of further applications is expected for the fabrication of nano and sub-nano electronic devices. [ABSTRACT FROM AUTHOR]

The mass spectra of the beam emitted by a Au82Si18 eutectic molten metal ion source are investigated in detail as a function of emitter temperature. At the conclusion of the work it emerges that while Au+, Si+, and Si++ are the result of direct field-evaporation from the liquid surface, Au++ forms by the post-ionisation of Au+. Cluster ions are most probably the product of droplet break-up. [ABSTRACT FROM AUTHOR]

In view of its importance in materials research, tin is a metal worth studying in a liquid metal ion source configuration, even if results complement or extend previous work. This is the more so if the new work corrects misconceptions of the past and adds to current thinking. We, therefore, prepared a Sn liquid metal ion source employing a Ni needle to anchor the liquid, cone-shaped, emitter. Source properties, such as the current–voltage curve, the mass spectra of the beam and the energy spread of the main ionic species, were studied in detail. The mass spectra show a considerable amount of Sn clusters, apart from the dominant species, Sn[sup +] and Sn[sup ++]. The source was stable down to 1-μA emission current, corresponding to an energy spread for the singly charged ions of 7 eV. Theoretical arguments, involving the peak energy deficit of the ion-energy distribution, strongly suggest that both Sn[sup +] and Sn[sup ++] are emitted by direct field evaporation from the liquid surface. The same conclusion is reached from a careful examination of the beam mass spectra of the source. [ABSTRACT FROM AUTHOR]

We have carried out a series of measurements demonstrating the feasibility of using the Dresden electron beam ion source (EBIS)-A, a table-top sized, permanent magnet technology based electron beam ion source, as a charge breeder. Low charged gold ions from an AuGe liquid metal alloy ion source were injected into the EBIS and re-extracted as highly charged ions, thereby producing charge states as high as Au60 +. The setup, the charge breeding technique, breeding efficiencies as well as acceptance and emittance studies are presented. [ABSTRACT FROM AUTHOR]

A carbon-cerium alloy liquid metal ion source (LMIS) with unintentional aluminum content is presented for generating focused ion beams of carbon ions, as well as ionized clusters with sizes of 2, 4, and 8 atoms. Emission-current-dependent measurements were carried out for the mass spectra and energy spread of all species, but focused on the carbon monomer ions and clusters. The full width at half maximum of the energy distribution was determined to be 6.5 eV for the monomer carbon ion and 14 eV for the light clusters at an emission current of 5 μA. The source showed good beam performance when used with a mass-separated focused ion beam column. Applications to graphene structures, organic matter, and other carbon-containing materials are promising tasks for the new carbon-containing alloy LMIS. [ABSTRACT FROM AUTHOR]