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This paper describes the design and operation of the Falcon ion source. It is based on conventional design of anode layer thrusters. This ion source is a versatile, compact, affordable, and highly functional in the research field of the fusion materials. The reversed magnetic field configuration of the source allows precise focusing of the ion beam into small spot of ≈3 mm and also provides the limited capabilities for impurity mass-separation. As the result, the source generates steady-state ion beam, which irradiates surface with high heat (0.3 - 21 MW m-2) and particle fluxes (4 × 1021 - 3 × 1023 m-2s-1), which approaches the upper limit for the flux range expected in ITER. [ABSTRACT FROM AUTHOR]

In the Budker Institute, Novosibirsk, an ion source with arc-discharge plasma box has been developed in the recent years for application in thermonuclear devices for plasma diagnostics. Several modifications of the ion source were provided with extracted current ranging from 1 to 7 A and pulse duration of up to 4 s. Initially, the arc-discharge plasma box with cold cathode was used, with which pulse duration is limited to 2 s by the cathode overheating and sputtering in local arc spots. Recently, a directly heated LaB6 electron emitter was employed instead, which has extended lifetime compared to the cold cathode. In the paper, characteristics of the beam produced with both arrangements of the plasma box are presented. [ABSTRACT FROM AUTHOR]

In this paper heavy negative-ion sources which we developed and their applications for materials science are reviewed. Heavy negative ions can be effectively produced by the ejection of a sputtered atom through the optimally cesiated surface of target with a low work function. Then, enough continuous negative-ion currents for materials-science applications can be obtained. We developed several kinds of sputter-type heavy negative-ion sources such as neutral- and ionized-alkaline metal bombardment-type heavy negative-ion source and rf-plasma sputter type. In the case where a negative ion is irradiated on a material surface, surface charging seldom takes place because incoming negative charge of the negative ion is well balanced with outgoing negative charge of the released secondary electron. In the negative-ion implantation into an insulator or insulated conductive material, high precision implantation processing with charge-up free properties can be achieved. Negative-ion implantation technique, therefore, can be applied to the following novel material processing systems: the surface modification of micrometer-sized powders, the nanoparticle formation in an insulator for the quantum devices, and the nerve cell growth manipulation by precise control of the biocompatibility of polymer surface. When a negative ion with low kinetic energy approaches the solid surface, the kinetic energy causes the interatomic bonding (kinetic bonding), and formation of a metastable material is promoted. Carbon films with high constituent of sp3 bonding, therefore, can be formed by carbon negative-ion beam deposition. [ABSTRACT FROM AUTHOR]

The European Rosetta mission on its way to comet 67P/Churyumov-Gerasimenko will remain for more than a year in the close vicinity (1 km) of the comet. The two ROSINA mass spectrometers on board Rosetta are designed to analyze the neutral and ionized volatile components of the cometary coma. However, the relative velocity between the comet and the spacecraft will be minimal and also the velocity of the outgassing particles is below 1 km/s. This combination leads to very low ion energies in the surrounding plasma of the comet, typically below 20 eV. Additionally, the spacecraft may charge up to a few volts in this environment. In order to simulate such plasma and to calibrate the mass spectrometers, a source for ions with very low energies had to be developed for the use in the laboratory together with the different gases expected at the comet. In this paper we present the design of this ion source and we discuss the physical parameters of the ion beam like sensitivity, energy distribution, and beam shape. Finally, we show the first ion measurements that have been performed together with one of the two mass spectrometers. [ABSTRACT FROM AUTHOR]

A joint research and development effort whose ultimate goal is to develop steady-state intense ion sources to meet the needs of the two energy extremes of ion implanters (mega-electron-volt and of hundreds of electron-volt) has been in progress for the past two years. Present day high-energy ion implanters utilize low charge state (usually single charge) ion sources in combination with rf accelerators. Usually, a MeV linear accelerator is used for acceleration of a few milliamperes. It is desirable to have instead an intense, high charge state ion source on a relatively low-energy platform (dc acceleration) to generate high-energy ion beams for implantation. This endeavor has already resulted in very high steady-state output currents of higher charge states antimony and phosphorous ions. Low-energy ion implantation is performed presently by decelerating high-energy extracted ions. Consequently, output currents are low due to space charge problems. Contamination is also a problem due to gases and plasmas employed to mitigate the space charge issues. Our efforts involve molecular ions and a plasmaless/gasless deceleration method. A program overview is presented in this article. Although source specifics are described in accompanying papers, only this article contains our most recent results. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the Solion ion source for high-throughput solar cell doping. As the source power is increased to enable higher throughput, negative effects degrade the lifetime of the plasma chamber and the extraction electrodes. In order to improve efficiency, we have explored a wide range of electron energies and determined the conditions which best suit production. To extend the lifetime of the source we have developed an in situ cleaning method using only existing hardware. With these combinations, source life-times of >200 h for phosphorous and >100 h for boron ion beams have been achieved while maintaining 1100 cell-per-hour production. [ABSTRACT FROM AUTHOR]

This paper presents measurements of the angular distribution of the plasma components and different charge states of metal ions generated by a MEVVA-type ion source and measured by a time-of-flight mass-spectrometer. The experiments were performed for different cathode materials (Al, Cu, and Ti) and for different parameters of the vacuum arc discharge. The results are compared with prior results reported by other authors. The influence of different discharge parameters on the angular distribution in a vacuum arc source is discussed. [ABSTRACT FROM AUTHOR]

In order to study beam optics of NIRS-ECR ion source used in the HIMAC project, the EGUN code has been modified to make it capable of modeling ion extraction from a plasma. Two versions of the modified code are worked out with two different methods in which 1D and 2D sheath theories are used, respectively. Convergence problem of the strong nonlinear self-consistent equations is investigated. Simulations on NiRS-ECR ion source and HYPER-ECR ion source are presented in this paper, exhibiting an agreement with the experiment results. [ABSTRACT FROM AUTHOR]

The plasma-chemical reactions of several materials are described in this paper. Materials such as quartz and platinum are used for containers of chemical reactions in various fields. Because of their stability chemical reactions do not occur easily, but such reactions can occur within the plasma of a rf ion source, and ion beams of such materials have been extracted from the ion source. This is because of the energetic plasma constituents and the bombardment of material surfaces by these high-energy particles. Various high-temperature chemical reactions can take place in the low-temperature (cool) plasma environment. [ABSTRACT FROM AUTHOR]

In this paper an ion source design is described. An ion beam with a current of 50 A, an energy of 30 keV, and a pulse duration of 0.1 s is extracted from a rectangular plasma emitter with dimensions of 24 × 12 cm. A new way is used for creating a uniform plasma current density at the emission surface. The source is distinguished from the typical bucket sources by its high degree of monatomic ions, the absence of heating cathodes, and an original ion-optic system design. [ABSTRACT FROM AUTHOR]

This paper presents a new design of ion sensitive probe (ISP) that enables collection of pure ion current for accurate measurement of the perpendicular ion temperature in magnetized plasmas. The new type of ISP resolves a longstanding issue widely observed in ISP type measurements, namely, that the current-voltage characteristic is smeared by an unexpected electron current in the standard ISP model. The new ISP is equipped with a fine scale metal mesh on the sensor entrance to prevent electrons from flowing to the sensor, a phenomenon considered to be caused by the space-charge effect. The new ISP successfully measured the ion temperature of electron cyclotron resonance plasmas. [ABSTRACT FROM AUTHOR]

Most electron cyclotron resonance ion sources use hexapolar magnetic fields for the radial confinement of the plasma. The geometry of this magnetic structure is then-induced by charged particles-mapped onto the inner side of the plasma electrode via sputtering and deposition. The resulting structures usually show two different patterns: a sharp triangular one in the central region which in some cases is even sputtered deep into the material (referred to as thin groove or sharp structure), and a blurred but still triangular-like one in the surroundings (referred to as broad halo). Therefore, both patterns seem to have different sources. To investigate their origins we replaced the standard plasma electrode by a custom-built plasma electrode acting as a planar, multi-segment current-detector. For different biased disc voltages, detector positions, and source biases (referred to the detector) we measured the electrical current density distributions in the plane of the plasma electrode. The results show a strong and sharply confined electron population with triangular shape surrounded by less intense and spatially less confined ions. Observed sputter- and deposition marks are related to the analysis of the results. Our measurements suggest that the two different patterns (thin and broad) indeed originate from different particle populations. The thin structures seem to be caused by the hot electron population while the broad marks seem to stem from the medium to highly charged ions. In this paper we present our measurements together with theoretical considerations and substantiate the conclusions drawn above. The validity of these results is also discussed. [ABSTRACT FROM AUTHOR]

The Quadrumafios electron cyclotron resonance ion source (ECRIS) has been especially designed to permit physical studies of the plasma; this paper describes the source itself (which has been operated at 10 GHz in a first step), its preliminary performances, and the different diagnostics involved, which mainly concern the electron population [electron cyclotron emission (ECE), x rays, diamagnetism, microwave interferometer, and electron analyzer]. The results are presented and discussed: There is of course a close relationship between the parameters of the plasma and the performances of the source; this point will be discussed in the article. [ABSTRACT FROM AUTHOR]