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ABSTRACT: Operation of liquid–metal ion sources based on palladium alloys that contain boron, arsenic, and phosphorus (singly or in combination) was studied. These sources, when run on refractory metal needles and heater ribbons, have exhibited high angular intensity (1.5–5 μA/sr), long lifetime (≫150 h), low energy spread (≪15 eV), and stable operation with extracted currents down to 2 μA.
Journal of vacuum science & technology. B, Microelectronics and nanometer structures: processing, measurement, and phenomena: an official journal of the American Vacuum Society 02/1987; · 1.34 Impact Factor
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ABSTRACT: We report an entirely new pattern‐replication technique for IC fabrication. It has demonstrated submicrometer (≪0.5 μm) resolution and it has the capability of large throughput (wafer‐levels/h). It utilizes high‐energy protons as the exposing radiation through a mask placed in proximity to a wafer covered with resist. We call this new technique ’’ion‐beam lithography’’ (IBL). System parameters and measurements relevant to the use of IBL as a production technology are discussed and SEM micrographs of submicrometer patterns in PMMA are presented. The technique is similar to x‐ray lithography, in that a pattern is produced in a thin resist film after exposing it to radiation through a mask. High‐energy protons have the same advantage as x rays in eliminating wavelength diffraction problems which limit the resolution of photolithography. Also, a gap (∼15–25 μm) is permitted between the mask and wafer. Ions have an advantage over x rays in that penumbral distortion is avoided by using highly collimated ion beams which are available with present state of the art; ions are collimated using conventional ion‐optical techniques, whereas use of a distant ’’point’’ source is the only feasible scheme for collimation of x rays.
Journal of Vacuum Science and Technology 12/1979;
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ABSTRACT: Microfabrication techniques are being investigated in which a focused high‐energy ion beam bombards a surface to create high‐resolution patterns of implantation doping, damage in crystal structures, or other chemical change such as molecular bond breaking. The objective is to demonstrate unique microfabrication techniques such as maskless implantation doping and the formation of self‐aligned structures. Preliminary results are presented of doped regions written in silicon by a focused boron beam. Electrical measurements on heavily doped contact regions and on a lightly doped resistive region are in good agreement with what would be expected from conventional ion implantation employing masks. The exposure of electron beam resist by a focused beam of 60‐keV helium ions is also reported. The resist sensitivity is ∼100 times greater for these ions than for electrons. The focused ion beam used in these studies was generated in a focusing arm which includes apertures, deflection plates, and an einzel lens that has been added to an existing ion implantation system. The focusing system performance is discussed and compared with the properties of a published electrostatic lens. Experimental results indicate a minimum beam spot diameter of ∼3.5 μm with a 150‐μm‐diam object aperture and a beam energy of ∼60 keV. Aperture diameters are calculated to produce a focused spot with submicrometer diameter.
Journal of Applied Physics 04/1974; · 2.17 Impact Factor
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R. L. Seliger
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ABSTRACT: The equations of motion are developed and solved for ion trajectories inside an E×B type mass separator. Curves are presented which illustrate the focusing of the undeflected ion beam, the trajectories along which ions of different mass species disperse inside the separator channel, and the exit slopes of mass species leaving the separator, as functions of a separator strength parameter. For strong separators, beam focusing is significant and is shown to be nonaxisymmetric when the electric and magnetic fields are uniform and orthogonal. A method of correcting the astigmatism by tilting the magnetic pole pieces is presented.
Journal of Applied Physics 06/1972; · 2.17 Impact Factor
