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Description
Boron ion beams are widely used for technologies. Firstly, it is boron doping of semiconductors, and secondly it is ion beam modification of the surface. Boron compounds have a high hardness, so such modification can significantly increase the life time of tools and machine parts. The boron rich ion beams were generated by vacuum arc ion source with two boron-containing cathodes. These are lanthanum hexaboride and boron carbide cathodes. The electrical conductivity of that cathodes was much more pure than that for boron and it allowed a stable work of a sub-millisecond pulse vacuum arc with hundreds amperes current. The parameters of the boron reach ion beam were measured. Using the time-of-flight mass spectrometer, the mass-charge state compositions of such ion beams were determined and compared with the stoichiometric composition of the cathodes. For lanthanum hexaboride and boron carbide cathodes the 100 /cm$^{2}$ cross section ion beams with 250 $\mu$s pulse duration and 0.5 A pulse current at 60 kV extractor voltage and ion boron particle fraction of 85 % and 80 %, correspondently, were obtained. The work was supported by the Russian Science Foundation under grant # 16-19-10034.
