Showing papers on "Focused ion beam published in 1980"

Dynamic range of 106 in depth profiling using secondary‐ion mass spectrometry

Abstract: Limitations in dynamic range previously experienced in SIMS depth profiling are shown to be caused by neutral projectiles present in the primary ion beam. Dynamic ranges of about 106 can be achieved if (i) the final section of the primary beam line and the sample are immersed in a UHV ambient (<10−6 Pa) and (ii) the beam traversing this region is deflected or offset from the gun axis so that energetic neutrals produced in the beam line do not hit the sample.

Low energy ion beam oxidation process

Abstract: A surface reaction process for controlled oxide growth is disclosed using a directed, low energy ion beam for compound or oxide formation. The technique is evaluated by fabricating Ni-oxide-Ni and Cr-oxide-Ni tunneling junctions, using directed oxygen ion beams with energies ranging from about 30 to 180 eV. In one embodiment, high ion current densities are achieved at these low energies by replacing the conventional dual grid extraction system of the ion source with a single fine mesh grid. Junction resistance decreases with increasing ion energy, and oxidation time dependence shows a characteristic saturation, both consistent with a process of simultaneous oxidation and sputter etching, as in the conventional r.f. oxidation process. In contrast with r.f. oxidized junctions, however, ion beam oxidized junctions contain less contamination by backsputtering, and the quantitative nature of ion beam techniques allows greater control over the growth process.

Dry development of resists exposed to focused gallium ion beam

Abstract: This report proposes a new lithography method employing focused ion beam exposure and subsequent dry development. It is shown that the plasma etching rate of resists exposed to gallium ions is much lower than that of resists not exposed. As this characteristic is applied to resist lithography, fine patterns can be obtained successfully. This dry development is applicable to many kinds of resist, such as PMMA, CMS, PGMA, FBM etc.

Characterisation of multiple-scan electron beam annealing method

Abstract: Beam power per unit area and exposure time are the predominant factors in defining implant anneal conditions for the multiple scan electron beam annealing technique. A theoretical analysis is presented which agrees with experimental results. Carrier concentration profiles confirm that the implant becomes electrically active without diffusion.

Reactive ion beam etching of SiO2 and polycrystalline silicon

Abstract: Reactive ion beam etching experiments using a collimated ion beam and the gases CF4, C2F6, and C3F8 have been conducted. At a beam current density of 0.4 mA/cm2 and ion energies from 0.5 to 1 keV the etch rates of SiO2 and polycrystalline silicon were 650 and 65 A/min, respectively, with C2F6 and C3F8. The etch selectivity was 10 to 1 for these gases though less than 2 to 1 for CF4. No undercutting was observed using this method.

Laser spectroscopic studies of molecular ions using fast ion beams

Abstract: The use of lasers and fast ion beams to study the spectroscopy of molecular Ions has experienced substantial growth over the past five years. Advantage has been taken of the amplification of center-of-mass energies in the laboratory frame, the compression of the velocity distribution when the ions are accelerated, and the ease of detection of single ions to study direct dissociations, predissociations and bound-bound transitions in a variety of ions, with varying degrees of resolution from 10 meV to 10 MHz. The ability to study dissociative processes in detail with high resolution is perhaps the most interesting application of the technique. Investigations of several ions are discussed, with the goal of illustrating the various types of studies which can be made. The extensive work on quartet states of [Math] is used as a case study of the kinds of results that should be available for a large number of ions in the near future.

Deposition of epitaxial layers by ion beam methods

Abstract: The possibilities and the limitations of ion beam sputter deposition are discussed in connection with results obtained for the growth of epitaxial semiconductor films. It turns out that homo‐ and hetero‐epitaxial films of good structural quality can be deposited at relatively low substrate temperatures and that effective doping offers no difficulties. On the other hand, some radiation damage caused by energetic particles must be taken into account. More recently, ion beam deposition methods could be realized under UHV conditions using about the same diagnostic equipment as in MBE. It can be expected that in preparing special film structures combinations between molecular and ion beam techniques might become attractive, while ion beam methods also will stand on its own in synthesizing unusual film phases.

Deposition of thin films of PZT by a focused ion beam sputtering technique

Abstract: Thin films of PZT have been deposited by an ion beam sputtering technique from a multicomponent target of lead zirconate titanate in an O2 atmosphere. These films were characterized according to composition, crystal structure, and dielectric and ferroelectric properties. The effect of deposition temperature, heat treatment after deposition, and substrate and target material were investigated.

Ion beam forming method

Abstract: PURPOSE:To enable the formation of various ion beams having minute diameter, by producing an ion beam while employing an alloy then selecting the ion beam of desired metal element. CONSTITUTION:The ions from injecting ion sources 1a, 1c and a self ion work cleaning ion source 1b are collected through lenses 2a, 2b, 2c and guided to a mass spectrograph 3. The mass spectrograph 3 will select the ion beam of required metal element such as As, B, Si from the ion beam of each alloy element. Said selected ion beam is focused through a lens means 4, while being deflection scanned by means of a beam deflection scanning means 5 and projected onto the predetermined position of a wafer arranged in a working chamber 6.

Deflected-Beam-Excited Ion-Cyclotron Beam Modes

Abstract: The electrostatic ion-cylcotron instability driven by a perpendicular (to the axial magnetic field) ion beam was observed in the University of Iowa MagPi II device. The perpendicular ion beam was produced by deflecting the injected parallel ion beam with a sufficiently positively biased Langmuir probe. The characteristic of the wave can be approximately described by a dispersion relation which is based on the fluid theory. The onset voltage of the instability was found to be a good measure of the incoming ion beam energy. A method which utilized the onset of this instability as an ion beam diagnostic also is proposed.

Fabrication of solar cells utilizing neutralized ion beam sputtering

Abstract: Using neutralized ion beam sputtering, large area, high efficiency indium tin oxide (ITO)/single and polycrystalline semiconductor-insulator-semiconductor (SIS) silicon solar cells have been fabricated. The principal fabrication steps are ion milling of the silicon surface using an argon-hydrogen-oxygen ion beam, low temperature and low pressure oxidation of the ion milled surface and reactive ion sputter deposition of ITO. Prior to ion milling, the polycrystalline material was chemically polished to remove surface contamination and saw damage. The ion beam sputtering system, device fabrication, operation and photovoltaic characteristics of ITO/silicon SIS solar cells are described. 14 refs.

Simple flying spot scanner for electron beam lithography on a scanning electron microscope without beam blanking capability

Abstract: A novel low‐cost flying spot scanner that allows a standard scanning electron microscope to be converted into an electron beam lithography system is described. Such a system is useful as a research tool for fabricating small arrays of submicron structures and devices.

Manufacturing of plastic molded article free from bleeding of additive

Abstract: PURPOSE:To prevent the bleeding of additives of a plastic molded article, by bombarding a target with ion beam emitted from an ion source of an inorganic gas under high vacuum, and depositing the ejected atoms to the surface of the molded article to form a dense film. CONSTITUTION:Inorganic gas 3 such as argon gas, nitrogen gas, etc. is introduced through an inlet 2 into an ion gun 1, and ionized by the electric discharge between the filament 4 and a counter-electrode. Ions are selectively extracted from the plasuma 5 by a negatively charged extraction electrode 6 to obtain an ion beam 7. The ion beam 7 is focused by focusing lenses 8 consisting of three electrostatic lenses. A target 10 made of carbon, silicon, etc. mounted in a vacuum chamber 9, is bombarded with the focused ion beam, and emits the atoms 11, which form a dense film on the surface of a plastic molded article 12.

Generation of structures on semiconductor surfaces - by producing charge mask on insulating surface which is then simultaneously irradiated by wide electron or ion beam

Abstract: A charge mask is produced on an insulating surface or ions are implanted in the semiconductor element. A charge mask is produced once by a focussed electron beam on an insulating layer. It is used for production of structures on the semiconductor surface by so irradiating the semiconductor surface by a widely spread electron or ion beam, that all points of the semiconductor platelet to be irradiated are simultaneously hit by the electron or ion beam. An electron source (6) generating a writing beam (8) is mounted on the symmetrical axis (7) of a semiconductor chip (9). The beam is focussed by an electrical or magnetic focussing system (10). The programmed control computer (12) switches the beam (8) on and off by means of control pulses conducted by a lead (13). One pair of deflection plates (14) is installed perpendicularly to the writing plane while another pair (15) is installed in parallel to it.

Current control technique in electron beam lithography

Abstract: An electron beam is periodically blanked off during its travel to reduce the time-averaged beam current. The effect of this current control is demonstrated using a negative-type electron resist, where a pattern gap varies from 1.0 mu m to 1.5 mu m.