Articles you may be interested inErratum: "Comparison of the submicron particle analysis capabilities of Auger electron spectroscopy, time-offlight secondary ion mass spectrometry, and scanning electron microscopy with energy dispersive x-ray spectroscopy for particles deposited on silicon wafers with one micron thick oxide layers" [J.Comparison of the submicron particle analysis capabilities of Auger electron spectroscopy, time-of-flight secondary ion mass spectrometry, and scanning electron microscopy with energy dispersive x-ray spectroscopy for particles deposited on silicon wafers with 1 μm thick oxide layers Development of a multifunctional surface analysis system based on a nanometer scale scanning electron beam: Combination of ultrahigh vacuumscanning electron microscopy, scanning reflection electron microscopy, Auger electron spectroscopy, and xray photoelectron spectroscopy Rev.Timeofflight secondary ion mass spectrometry of insulators with pulsed charge compensation by lowenergy electrons J.Particulate contamination can result in a significant yield loss during semiconductor device fabrication. As device design rule dimensions decrease the critical defect size also decreases, resulting in the need to analyze smaller defects. Current manufacturing requirements include analysis of sub-0.5-m defects, with analysis of sub-0.1-m defects expected in the near future. This article investigates the particle analysis capabilities of Auger electron spectroscopy, time-of-flight secondary ion mass spectrometry, and energy dispersive x-ray spectroscopy during scanning electron microscopy ͑SEM/EDS͒. In order to evaluate each method carefully, a standard set of samples was prepared and analyzed. These samples consist of 0.5-, 0.3-, and 0.1-m Al and Al 2 O 3 deposited on 1-in. Si wafers. Although all the methods observed an Al signal, a semiquantitative gauge of capability based on the relative strengths of particle versus substrate signal is provided. The dependence of the sample-to-substrate signal on primary electron energy is examined for both EDS and Auger analyses. The ability to distinguish metallic Al particles from Al oxide particles for the three techniques is also discussed.

Electrical characterization of pseudomorphic GaAs/InGaAs/AlGaAs and AlGaAs/InGaAs/AlGaAs modulation doped field effect transistortype heterostructures grown by molecularbeam epitaxy

The combination of molecular-beam epitaxy with focused ion beam (FIB) technology offers the opportunity for generating true three-dimensional ultrasubmicron structures. One problem, however, is that conventional FIB systems employ landing energies of ∼50 keV and up, and so the spatial extent of damage by the beam, exceeds both the radius of the beam and the thickness of layers frequently grown. We have investigated focusing of beams of ions of energies down to 25 eV by employing retarding field optics. Modeling of the optics indicates that space charge becomes serious at currents above 1 nA for Ga+ ions of 50-eV energy but that submicron beams of such ions are possible at lower currents. An experimental column was built and largely confirmed the predictions. Beam diameters were measured to be within a factor of 2 of the predicted value with a value of 0.95 μm for a 1-nA beam of Ga+ ions of landing energy of 25 eV.

A novel ion focused beam system has recentiy been designed and constructed that employs retarding field, electrostatic optics such that beams ofGa + ions with energies as low as 25 eV can be focused into a submicron diameter spot. In this paper we review the ion-optical performance of this system and then describe the interactions of the beam with the target. In the conventional mode OO-keV landing energy) the system has been used to sputter etch tracks in gold (on a silicon substrate) of width 0.16 f1m. However, as the landing energy is reduced below 200 eV, the action of sputter etching gives way to deposition and tracks of gallium 1.5 to 3 f1 wide have been laid down in this manner. That the tracks were indeed gallium was confirmed by x-ray microanalysis. The appearance of the tracks suggested that the interface between the gallium and the substrate affects the morphology of the track. Two obvious and prosaic applications include the repair of both clear and opaque mask defects, and making and breaking integrated circuit electrical interconnections. More ambitious applications include combining the system with molecular-beam epitaxy to build true three-dimensional, sub-O.l-f1m device structures.

Computerized scanning Auger microprobe J. Vac. Sci. Technol. A 3, 526 (1985); 10.1116/1.572986Ion scattering spectrometry in a commercial scanning Auger microprobe Rev. Sci. Instrum. 55, 542 (1984); Abstract: Study of composition changes under ion eombardment in the scanning Auger microprobe A probe forming electron optical system utilizing Schottky field emission cathode technology has been designed and optimized for application to high spatial resolution scanning Auger microscopy (SAM). This article examines optics design trade-off's driven by the unique requirements of SAM, summarizes the theoretical performance limits of the resulting design, and compares simulation and experimental results over a wide range of operating conditions. Experimental results reported include beam diameter as a function of voltage and current, and beam current stability in various modes of operation (;$ 1 %ih under optimum conditions). Experimental beam size data are compared to limits set by the magnified source, spherical and chromatic aberration, deflection aberrations, diffraction and space charge effects. The optical system is designed to operate at beam voltages ranging from < 1 to 25 kV, with beam current at the sample of < 1-100 nA. The operational mode of the instrument is chosen to emphasize either high spatial resolution (at the expense of maximum current) or high throughput (at the expense of spatial resolution) under the discretion of the operator. Switching from one to the other is accomplished by a change in the voltage applied to the extraction anode, resulting in the desired angular emission intensity J n. The time required for stabilization of the source after such a change has been found to be acceptable; for example, following a change from 0.25 to 1.0 mA/sr, beam current drift of ;$ 2%/h is generally achieved in less than 60 min.