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A retarding-field differential-output energy prefilter has been optically matched to a quadrupole mass spectrometer to produce a high-performance secondary ion quadrupole mass spectrometer. The sample area was designed to be field free to allow for sample charge compensation and to prevent secondary ion trajectories from being affected by electric fields. Design considerations for optically matching the energy prefilter to the quadrupole mass filter (QMF) are discussed. The overall transmission of the instrument was 1.8×10−4 at a mass resolution of 100 M/ΔM (1–100 amu range) for copper and 1.7×10−5 at a mass resolution of 400 M/ΔM (10–250 amu range) for tungsten.

An experimental method that increases the analyzer resolution of cylindrical mirror analyzer CMA-based Auger spectrometers is described. By means of electrically biasing the sample, the effective energy resolution obtainable from the CMA instrument is improved from the native 0.5 to 0.1% or even better for higher kinetic energy Auger transitions. In addition, the maximum kinetic energy Auger transition observable by the CMA Auger instrument is increased from 3200 to 5700 eV, in the current realization. It is also shown that the sensitivity of the energy scale calibration to sample working distance with respect to the analyzer is simultaneously reduced, making the method suitable for chemical surface analysis. The biasing is accomplished using a special sample holder with electronics and software that can be added to an existing instrument. The overall capability of the Auger instrument for chemical analysis is, therefore, increased, while preserving all the analytical functionality and features of the CMA.

A Monte Carlo simulation method is presented for calculating line shapes for charged-particle analyzers with cylindrical symmetry. Either isotropic or cosine angular distributions of charged-particle emission can be simulated. Application of this technique is demonstrated by simulation of the line shape exhibited by the Helmer planar-retarding-grid analyzer. Ray tracing is used to determine the origin of line-shape asymmetry, new entrance optics are designed, and subsequently, a simulation is used to optimize the dimensions of the analyzer apertures and beam stop to produce a symmetric nearly Gaussian line shape. This result is then verified experimentally. Although the simulation method is applied to a specific problem, it should prove to be of value for the design of any analyzer having axial symmetry.